Swedish Rectal Cancer Trial: long lasting benefits from radiotherapy on survival and local recurrence rate

Interrater Agreement of Height Assessment by Rigid Proctoscopy/Rectoscopy for Rectal Carcinoma

BACKGROUND

Some guidelines for rectal carcinoma consider 12 cm, measured by rigid endoscopy, to be the cutoff tumor height for optional neoadjuvant chemoradiation therapy. Measuring differences of only a few centimeters may predetermine the choice of further therapy. However, rigid endoscopy may exhibit similar operator dependence to most other clinical examination methods.

OBJECTIVES

Evaluation of concordance of rigid rectoscopic tumor height measurements performed by 4 experienced examiners, 2 measuring with patients in the lithotomy position and 2 in the left lateral position. Assessment of tumor palpability and distance of the anal verge to the anocutaneous line were also evaluated.

DESIGN

This study used a prospective observational design.

SETTING

This study was conducted at an academic teaching hospital that is a referral center for colorectal surgery.

PATIENTS

There were 50 patients, of whom 35 were men (70%). The median age was 72.5 years (53-88 years).

MAIN OUTCOME MEASURES

Interrater agreement of tumor height assessment and tumor height of less than or greater than the 12-cm height limit.

RESULTS

With an intraclass correlation coefficient of 0.947 (95% CI, 0.918-0.967, p < 0.001), interrater reliability of tumor height assessment was statistically rated "excellent." Despite this, in 26% of patients, there was no agreement regarding the allocation of the tumor <12- or >12-cm height limit. Furthermore, there was also considerable disagreement concerning tumor palpability and the distance of the anal verge to the anocutaneous line. Patient positioning was not found to influence results.

LIMITATIONS

Single-center study.

CONCLUSIONS

Rigid rectal endoscopy may not be a sound pivotal basis for the consideration of optional chemoradiation therapy in rectal carcinoma. Application of a universally valid height limit ignores biological variability in body frame, gender, and acquired pelvic descent. Eligibility for neoadjuvant therapy should not rely on height measurements alone. Uniform MRI or CT imaging protocols, based on agreed upon terminology, including factors such as tumor height relative to the pelvic frame and peritoneal reflection, may be an important diagnostic addition to such a decision. See Video Abstract .Clinical trial registration: DRKS00012758 (German National Study Registry), ST-D 406 (German Cancer Society).

ACUERDO ENTRE EVALUADORES EN LA EVALUACIN DE LA ALTURA MEDIANTE PROCTO/ RECTOSCOPIA RGIDA PARA EL CARCINOMA DE RECTO

ANTECEDENTES:Algunas guías para el carcinoma de recto consideran que 12 cm, medidos mediante endoscopia rígida, es la altura de corte del tumor para la quimiorradiación neoadyuvante opcional. Por lo tanto, una diferencia de medición de sólo unos pocos centímetros puede predeterminar la elección de una terapia adicional. Sin embargo, la endoscopia rígida puede presentar una dependencia del operador similar a la de la mayoría de los demás métodos de examen clínico.OBJETIVOS:Evaluación de la concordancia de las mediciones de la altura del tumor rectoscópico rígido realizadas por cuatro examinadores experimentados, dos en litotomía y dos en posición lateral izquierda. También se evaluó la evaluación de la palpabilidad del tumor y la distancia del borde anal a la línea anocutánea.DISEÑO:Estudio observacional prospectivo.LUGAR:Hospital universitario, centro de referencia para cirugía colorrectal.PACIENTES:50 pacientes, 35 varones (70%), mediana de edad 72,5 años (53-88 años).PRINCIPALES MEDIDAS DE RESULTADOS:Acuerdo entre evaluadores en la evaluación de la altura del tumor y la asignación del tumor por debajo o más allá del límite de altura de 12 cm.RESULTADOS:Con un coeficiente de correlación intraclase de 0,947 (IC del 95%: 0,918-0,967, p < 0,001), la confiabilidad entre evaluadores de la evaluación de la altura del tumor se calificó estadísticamente como "excelente". A pesar de esto, en el 26% de los pacientes no hubo acuerdo sobre la asignación del tumor por debajo o por encima del límite de 12 cm de altura. Además, también hubo un considerable desacuerdo con respecto a la palpabilidad del tumor y la distancia del borde anal a la línea anocutánea. No se encontró que la posición del paciente influyera en los resultados.LIMITACIONES:Estudio unicéntrico.CONCLUSIONES:La endoscopia rectal rígida puede no ser una base sólida y fundamental para considerar la quimiorradiación opcional en el carcinoma de recto. La aplicación de un límite de altura universalmente válido obviamente ignora la variabilidad biológica en la constitución corporal, el género y el descenso pélvico adquirido. La elegibilidad para la terapia neoadyuvante no debe depender únicamente de las mediciones de altura. Los protocolos uniformes de imágenes por resonancia magnética o tomografía computarizada, basados en una terminología acordada, incluidos factores como la altura del tumor en relación con la estructura pélvica y la reflexión peritoneal, pueden ser una adición diagnóstica importante para tal decisión. (Traducción-Yesenia Rojas-Khalil )Clinical trial registration: DRKS00012758 (German National Study Registry), ST-D 406 (German Cancer Society).

Current State of Neoadjuvant Therapy for Locally Advanced Rectal Cancer

ABSTRACT

In locally advanced rectal cancer, neoadjuvant treatment has evolved from no preoperative treatment to the addition of radiation and systemic therapy and ultimately total neoadjuvant therapy. Total neoadjuvant therapy is the completion of preoperative radiation or chemoradiation and chemotherapy before surgery in order to maximize tumor response and improve survival outcomes. This review summarizes the literature of the neoadjuvant approaches related to locally advanced rectal cancer and highlights the nuances of selecting the appropriate treatment.

T3N0 Rectal Cancer: Radiation for All, None, or Some?

ABSTRACT

The optimal management of T3N0 rectal cancer is an area of active debate that has withstood multiple decades of research. In this comprehensive review, we delve into the many nuances that come with treating T3N0 rectal cancer, particularly examining the role and evolution of radiation therapy. We review both the historical paradigms and latest advances in treatment and highlight the significance of precise preoperative staging. As the field continues to evolve, this review highlights a shift toward more tailored treatments, considering both patient goals and the desire for optimal oncologic outcomes. In the current era, clinical decision-making for T3N0 rectal cancer requires a patient-centric approach that balances effective therapy while minimizing undue side effects.

Nonoperative Management for Rectal Cancer

ABSTRACT

The treatment paradigm for rectal cancer has been shifting toward de-escalated approaches to preserve patient quality of life. Historically, the standard treatment in the United States for locally advanced rectal cancer has standardly comprised preoperative chemoradiotherapy coupled with total mesorectal excision. Recent data challenge this "one-size-fits-all" strategy, supporting the possibility of omitting surgery for certain patients who achieve a clinical complete response to neoadjuvant therapy. Consequently, patients and their physicians must navigate diverse neoadjuvant options, often in the context of pursuing organ preservation. Total neoadjuvant therapy, involving the administration of all chemotherapy and radiation before total mesorectal excision, is associated with the highest rates of clinical complete response. However, questions persist regarding the optimal sequencing of radiation and chemotherapy and the choice between short-course and long-course radiation. Additionally, meticulous response assessment and surveillance are critical for selecting patients for nonoperative management without compromising the excellent cure rates associated with trimodality therapy. As nonoperative management becomes increasingly recognized as a standard-of-care treatment option for patients with rectal cancer, ongoing research in patient selection and monitoring as well as patient-reported outcomes is critical to guide personalized rectal cancer management within a patient-centered framework.

Radiotherapy for Rectal Cancer: How Much is Enough?

Though resection has been the mainstay of treatment for nonmetastatic rectal cancer over the past century, radiation has become an increasingly integral component of care for locally advanced disease. Today, two predominant radiotherapy approaches-hyperfractionated chemoradiotherapy and "short-course" radiation-are widely utilized to reduce local recurrence and, in some cases, cure disease. Both have been incorporated into total neoadjuvant therapy (TNT) regimens and achieved excellent local control and superior complete response rates compared to chemoradiation alone. Additionally, initial results of "watch and wait" protocols utilizing either radiation modality have been promising. Yet, differences do exist; though short course is cheaper and more convenient for patients, recently published data may show superior complete response and local recurrence rates with chemoradiation. Ultimately, direct comparisons of short-course radiotherapy against chemoradiation within the TNT framework are needed to identify optimal radiation regimens in the treatment of locally advanced rectal cancer.

Mechanism of the Radioresistant Colorectal Cancer Cell Line SW480RR Established after Fractionated X Irradiation

Radioresistant cancer cells are risk factors for recurrence and are occasionally detected in recurrent tumors after radiotherapy. Intratumor heterogeneity is believed to be a potential cause of treatment resistance. Heterogeneity in DNA content has also been reported in human colorectal cancer; however, little is known about how such heterogeneity changes with radiotherapy or how it affects cancer radioresistance. In the present study, we established radioresistant clone SW480RR cells after fractionated X-ray irradiation of human colorectal cancer-derived SW480.hu cells, which are composed of two cell populations with different chromosome numbers, and examined how cellular radioresistance changed with fractionated radiotherapy. Compared with the parental cell population, which mostly comprised cells with higher ploidy, the radioresistant clones showed lower ploidy and less initial DNA damage. The lower ploidy cells in the parental cell population were identified as having radioresistance prior to irradiation; thus, SW480RR cells were considered intrinsically radioresistant cells selected from the parental population through fractionated irradiation. This study presents a practical example of the emergence of radioresistant cells from a cell population with ploidy heterogeneity after irradiation. The most likely mechanism is the selection of an intrinsically radioresistant population after fractionated X-ray irradiation, with a background in which lower ploidy cells exhibit lower initial DNA damage.

Impact of adjuvant chemotherapy on survival after pathological complete response in rectal cancer: a meta-analysis of 31,558 patients

BACKGROUND

Locally advanced rectal cancer (LARC) typically involves neoadjuvant chemoradiotherapy (nCRT) followed by surgery (total mesorectal excision, TME). While achieving a complete pathological response (pCR) is a strong indicator of a positive prognosis, the specific benefits of adjuvant chemotherapy after pCR remain unclear. To address this knowledge gap, we conducted a systematic review and meta-analysis to assess the potential advantages of adjuvant therapy in patients who achieve pCR.

METHODS

In this study, we searched Medline, Embase, and Web of Science databases for relevant research. We focused on binary outcomes, analyzing them using odds ratios (ORs) with 95% confidence intervals (CIs). To account for potential variability between studies, all endpoints were analyzed with DerSimonian and Laird random-effects models. We assessed heterogeneity using the I2 statistic and employed the R statistical software (version 4.2.3) for all analyses.

RESULTS

Thirty-four studies, comprising 31,558 patients, were included. The outcomes demonstrated a significant difference favoring the AC group in terms of overall survival (OS) (HR 0.75; 95% CI 0.60-0.94; p = 0.015; I2 = 0%), and OS in 5 years (OR 1.65; 95% CI 1.21-2.24; p = 0.001; I2 = 39%). There was no significant difference between the groups for disease-free survival (DFS) (HR 0.94; 95% CI 0.76-1.17; p = 0.61; I2 = 17%), DFS in 5 years (OR 1.19; 95% CI 0.82-1.74; p = 0.36; I2 = 43%), recurrence-free survival (RFS) (HR 1.10; 95% CI 0.87-1.40; p = 0.39; I2 = 0%), and relapse-free survival (OR 1.08; 95% CI 0.78-1.51; p = 0.62; I2 = 0%).

CONCLUSION

This systematic review and meta-analysis found a significant difference in favor of the ACT group in terms of survival after pCR. Therefore, the administration of this treatment as adjuvant therapy should be encouraged in clinical practice.

Effects of Adjuvant Chemotherapy on Oncologic Outcomes in Patients With Stage ⅡA Rectal Cancer Above the Peritoneal Reflection Who Did Not Undergo Preoperative Chemoradiotherapy

PURPOSE

This study aimed to evaluate the effects of adjuvant chemotherapy (AC) on oncologic outcomes for patients with stage IIA upper rectal cancer and to investigate whether AC is associated with improved survival outcomes.

METHODS

This retrospective study comprised 432 patients with rectal cancer above the peritoneal reflection who had undergone curative resection without preoperative chemoradiotherapy between 2008 and 2016. This study cohort was divided according to whether AC was received (AC group) or not (no-AC group). Risk factors included obstruction, perforation, poorly-differentiated tumor, lympho-vascular invasion, perineural invasion, resection margin involvement, and < 12 lymph nodes harvested.

RESULTS

Among the 432 patients, 279 (64.6%) had received AC. The AC group had significantly higher 5-year overall survival (OS) rates than those of the no-AC group (93.2% vs. 84.6%, P = .001). Among patients with ≥ 1 risk factors, the AC group (n = 123) had significantly higher rates of 5-year recurrence-free survival (RFS) (81.6% vs. 64.1%, P = .01) and 5-year OS (88.8% vs. 69.0%, P = .001) than those of the no-AC group (n = 59). No significant difference in survival outcomes was observed between the 2 groups in patients aged > 65 years.

CONCLUSION

AC was significantly associated with better 5-year RFS and 5-year OS rates in patients with stage IIA rectal cancer above peritoneal reflection who did not receive preoperative chemoradiotherapy, especially in those with ≥ 1 risk factors.

Long-term restoration of bowel continuity after rectal cancer resection and the influence of surgical technique: A nationwide cross-sectional study

AIM

Literature on nationwide long-term permanent stoma rates after rectal cancer resection in the minimally invasive era is scarce. The aim of this population-based study was to provide more insight into the permanent stoma rate with interhospital variability (IHV) depending on surgical technique, with pelvic sepsis, unplanned reinterventions and readmissions as secondary outcomes.

METHOD

Patients who underwent open or minimally invasive resection of rectal cancer (lower border below the sigmoid take-off) in 67 Dutch centres in 2016 were included in this cross-sectional cohort study.

RESULTS

Among 2530 patients, 1470 underwent a restorative resection (58%), 356 a Hartmann's procedure (14%, IHV 0%-42%) and 704 an abdominoperineal resection (28%, IHV 3%-60%). Median follow-up was 51 months. The overall permanent stoma rate at last follow-up was 50% (IHV 13%-79%) and the unintentional permanent stoma rate, permanent stoma after a restorative procedure or an unplanned Hartmann's procedure, was 11% (IHV 0%-29%). A total of 2165 patients (86%) underwent a minimally invasive resection: 1760 conventional (81%), 170 transanal (8%) and 235 robot-assisted (11%). An anastomosis was created in 59%, 80% and 66%, with corresponding unintentional permanent stoma rates of 12%, 24% and 14% (p = 0.001), respectively. When corrected for age, American Society of Anesthesiologists classification, cTNM, distance to the anorectal junction and neoadjuvant (chemo)radiotherapy, the minimally invasive technique was not associated with an unintended permanent stoma (p = 0.071) after a restorative procedure.

CONCLUSION

A remarkable IHV in the permanent stoma rate after rectal cancer resection was found. No beneficial influence of transanal or robot-assisted laparoscopy on the unintentional permanent stoma rate was found, although this might be caused by the surgical learning curve. A reduction in IHV and improving preoperative counselling for decision-making for restorative procedures are required.

Comparative analysis of preoperative chemoradiotherapy and upfront surgery in the treatment of upper-half rectal cancer: oncological benefits, surgical outcomes, and cost implications

The value of neoadjuvant chemoradiotherapy (CRT) is not absolutely clear for upper-half (> 7-15 cm) rectal cancer. This study aimed to compare the efficacy and safety of radical surgery with preoperative CRT vs. upfront surgery (US) in Chinese patients with stage II and III upper-half rectal cancer. A total of 809 patients with locally advanced upper-half rectal cancer between 2017 and 2021 were enrolled retrospectively (280 treated with CRT and 529 treated with US). Through 1:1 propensity score matching, the CRT (172 patients) and US (172 patients) groups were compared for short-term postoperative results and long-term oncological and functional outcomes. In the entire cohort, patients in the CRT group had a younger age, lower distance from the anal verge (DAV), and higher rates of cT4 stage, cN2 stage, mrCRM positivity, EMVI positivity, CEA elevation, and CA-199 elevation than those in the US group. The 5-year disease-free survival (DFS) was lower in the CRT group than in the US group (76% vs. 84%, p = 0.022), while the 5-year overall survival (OS) was comparable between the two groups (85% and 88%, p = 0.084). The distant metastasis rate was higher in the CRT group than in the US group (12.5% vs. 7.8%, p = 0.028), though the local recurrence rate was similar between the two groups (1.1% and 1.3%, p = 1.000). After performing PSM, the 5-year OS (86% vs. 88% p = 0.312), the 5-year DFS (79% vs. 80%, p = 0.435), the local recurrence rate (1.2% vs. 1.7%, p = 1.000), and the distant metastasis rate (11.0% vs. 9.3%, p = 0.593) were comparable between the two groups. Notable pathological downstaging was observed in the CRT group, with a pathological complete response (PCR) rate of 14.5%. In addition, patients in the CRT group had a lower proportion of pT3 (61.6% vs. 77.9%, p < 0.001), pN + (pN1, 15.1% vs. 30.2%, pN2, 9.3% vs. 20.3%, p < 0.001), stage III (24.4% vs. 50.6%, p < 0.001), perineural invasion (19.8% vs. 32.0%, p = 0.014), and lymphovascular invasion (9.3% vs. 25.6%, p < 0.001) than those in the US group. Postoperative complications and long-term functional results were similar, yet there was a trend toward a higher conversion to laparotomy rate (5 (2.9%) vs. 0 (0.0%), p = 0.061) and higher rates of robotic surgery (11.6% vs. 4.7%, p < 0.001), open surgery (7.0% vs. 0.6%, p < 0.001), diverting stoma (47.1% vs. 25.6%, p < 0.001), and surgery costs (1473.6 ± 106.5 vs. 1140.3 ± 54.3$, p = 0.006) in the CRT group. In addition, EMVI (OR = 2.516, p = 0.001) was the only independent risk factor associated with poor response to CRT, and in subgroup analysis of EMVI + , CRT group patients presented a lower 5-year DFS (72.9% vs. 80.5%, p = 0.025) compared to US group patients. CRT prior to surgery has no additional oncological benefits over US in the treatment of upper-half rectal cancer. In contrast, CRT is associated with increased rates of conversion to laparotomy, stoma creation and higher surgery costs. Surgeons tend to favor robotic surgery in the treatment of complex cases such as radiated upper-half rectal cancers. Notably, EMVI + patients with upper-half rectal cancer should be encouraged to undergo upfront surgery, as preoperative CRT may not provide benefits and may lead to delayed treatment effects.

Future direction of total neoadjuvant therapy for locally advanced rectal cancer

Despite therapeutic advancements, disease-free survival and overall survival of patients with locally advanced rectal cancer have not improved in most trials as a result of distant metastases. For treatment decision-making, both long-term oncologic outcomes and impact on quality-of-life indices should be considered (for example, bowel function). Total neoadjuvant therapy (TNT), comprised of chemotherapy and radiotherapy or chemoradiotherapy, is now a standard treatment approach in patients with features of high-risk disease to prevent local recurrence and distant metastases. In selected patients who have a clinical complete response, subsequent surgery might be avoided through non-operative management, but patients who do not respond to TNT have a poor prognosis. Refined molecular characterization might help to predict which patients would benefit from TNT and non-operative management. Specifically, integrated analysis of spatiotemporal multi-omics using artificial intelligence and machine learning is promising. Three prospective trials of TNT and non-operative management in Japan, the USA and Germany are collaborating to better understand drivers of response to TNT. Here, we address the future direction for TNT.

Prediction of survival after neoadjuvant therapy in locally advanced rectal cancer - a retrospective analysis

Purpose

The aim of this retrospective analysis was to determine if the response to preoperative radio(chemo)therapy is predictive for survival among patients with locally advanced rectal cancer and may act as a potential surrogate endpoint for disease free survival and overall survival.

Results

Eight hundred seventy-eight patients from five centers were analyzed. There were 304 women and 574 men; the median age was 64.7 years. 77.6% and 22.4% of patients received neoadjuvant radiochemotherapy or short-course radiotherapy, resulting in a pathological complete response in 7.3%. T-downstaging and N-downstaging occurred in 50.5% and 37% of patients after neoadjuvant therapy. In patients with T-downstaging, the 10-year DFS and 10-year OS were 64.8% and 66.8% compared to 37.1% and 45.9% in patients without T-downstaging. N-downstaging resulted in 10-year DFS and 10-year OS in 56.2% and 62.5% compared to 47.3% and 52.3% without N-downstaging. Based on routinely evaluated clinical parameters, an absolute risk prediction calculator was generated for 5-year disease-free survival, and 5-year overall survival.

Conclusion

T-downstaging and N-downstaging after neoadjuvant radiochemotherapy or short-course radiotherapy resulted in better DFS and OS compared to patients without response. Based on clinical parameters, 5-year DFS, and 5-year OS can be predicted using a prediction calculator.

MicroRNA-298 determines the radio-resistance of colorectal cancer cells by directly targeting human dual-specificity tyrosine(Y)-regulated kinase 1A

BACKGROUND

Radiotherapy stands as a promising therapeutic modality for colorectal cancer (CRC); yet, the formidable challenge posed by radio-resistance significantly undermines its efficacy in achieving CRC remission.

AIM

To elucidate the role played by microRNA-298 (miR-298) in CRC radio-resistance.

METHODS

To establish a radio-resistant CRC cell line, HT-29 cells underwent exposure to 5 gray ionizing radiation that was followed by a 7-d recovery period. The quantification of miR-298 levels within CRC cells was conducted through quantitative RT-PCR, and protein expression determination was realized through Western blotting. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and proliferation by clonogenic assay. Radio-induced apoptosis was discerned through flow cytometry analysis.

RESULTS

We observed a marked upregulation of miR-298 in radio-resistant CRC cells. MiR-298 emerged as a key determinant of cell survival following radiation exposure, as its overexpression led to a notable reduction in radiation-induced apoptosis. Intriguingly, miR-298 expression exhibited a strong correlation with CRC cell viability. Further investigation unveiled human dual-specificity tyrosine(Y)-regulated kinase 1A (DYRK1A) as miR-298's direct target.

CONCLUSION

Taken together, our findings underline the role played by miR-298 in bolstering radio-resistance in CRC cells by means of DYRK1A downregulation, thereby positioning miR-298 as a promising candidate for mitigating radio-resistance in CRC.

Update on Dosing and Fractionation for Neoadjuvant Radiotherapy for Localized Soft Tissue Sarcoma

OPINION STATEMENT

Neoadjuvant radiotherapy (RT) over 5-6 weeks with daily doses of 1.8-2.0 Gy to a total dose of 50-50.4 Gy is standard of care for localized high-grade soft tissue sarcomas (STS) of the extremities and trunk wall. One exception is myxoid liposarcomas where the phase II DOREMY trial applying a preoperative dose of 36 Gy in 2 Gy fractions (3-4 weeks treatment) has achieved excellent local control rates of 100% after a median follow-up of 25 months.Hypofractionated preoperative RT has been investigated in a number of phase II single-arm studies suggesting that daily doses of 2.75-8 Gy over 1-3 weeks can achieve similar oncological outcomes to conventional neoadjuvant RT. Prospective data with direct head-to-head comparison to conventional neoadjuvant RT investigating oncological outcomes and toxicity profiles is eagerly awaited.For the entire group of retroperitoneal sarcomas, RT is not the standard of care. The randomized multi-center STRASS trial did not find a benefit in abdominal recurrence-free survival by the addition of preoperative RT. However, for the largest histological subgroup of well-differentiated and grades I and II dedifferentiated liposarcomas, the STRASS trial and the post-hoc propensity-matched STREXIT analysis have identified a possible benefit in survival by preoperative RT. These patients deserve to be informed about the pros and cons of preoperative RT while the longer follow-up data from the STRASS trial is awaited.

Neoadjuvant Short- Vs. Long-Course Radiation for Locally Advanced Rectal Cancer: How to Choose

OPINION STATEMENT

Over the past decades, the treatment of locally advanced rectal cancer has evolved dramatically due to improvements in diagnostic imaging, surgical technique, and the addition of radiotherapy and/or chemotherapy. Fractionation of neoadjuvant radiotherapy with or without concurrent chemotherapy remains the subject of discussion and the question multiple recent trials have aimed to answer. In light of recent data and concern for locoregional recurrence, our institution favors long-course chemoradiation in most cases, especially in low-lying primaries, threatened circumferential resection margin, consideration of non-operative management, or if the surgeon has concerns for resectability. Exceptions would include cases of oligometastatic disease planned for metastasectomy in which curative-intent treatment was pursued or if additional factors required a reduction in treatment time.

Efficacy and Safety of Preoperative Transcatheter Rectal Arterial Chemoembolisation in Patients with Locally Advanced Rectal Cancer: Results from a Prospective, Phase II PCAR Trial

AIMS

The PCAR study aimed to assess the efficacy and safety of preoperative transcatheter rectal arterial chemoembolisation (TRACE) in patients with locally advanced rectal cancer (LARC).

MATERIALS AND METHODS

This was a single-centre, prospective, phase II trial conducted in China. Eligible patients were adults aged 18 years and older with histologically confirmed stage II or III rectal carcinoma and an Eastern Cooperative Oncology Group performance status of 0-1. Patients received TRACE with oxaliplatin, followed by radiotherapy with a cumulative dose of 45 Gy (1.8 Gy/time/day, five times a week for 5 weeks) and received oral S1 capsules twice daily (7 days a week for 4 weeks). Patients underwent total mesorectal excision 4-8 weeks after the completion of chemoradiotherapy, followed by mFOLFOX6 or CAPOX regimens for 4-6 months. The hypothesis of this study was that adding TRACE to preoperative neoadjuvant chemoradiotherapy would improve tumour regression and prognosis. The primary end point was the pathological complete response rate; secondary end points included the major pathological response rate, anal preservation rate, 5-year disease-free survival (DFS), 5-year overall survival and treatment-related adverse events.

RESULTS

In total, 111 LARC patients received TRACE and subsequent scheduled treatment plans. The pathological complete response and major pathological response rates were 20.72% and 48.65%, respectively. The 5-year DFS and 5-year overall survival were 61.89% (95% confidence interval 51.45-74.45) and 74.80% (95% confidence interval 65.05-86.01), respectively. Grade 3-4 toxicities were reported in 29 patients (26.13%). The postoperative complication rate was 21.62%, without serious surgical complications. Multivariate Cox regression analysis showed that ypN stage (hazard ratio = 4.242, 95% confidence interval 2.101-8.564, P = 0.00017) and perineural invasion (hazard ratio = 2.319, 95% confidence interval 1.058-5.084, P = 0.0487) were independent risk factors associated with DFS, whereas ypN stage (hazard ratio = 3.164, 95% confidence interval 1.347-7.432, P = 0.0101), perineural invasion (hazard ratio = 4.118, 95% confidence interval 1.664-10.188, P = 0.0134) and serum carbohydrate antigen 199 (CA199; hazard ratio = 4.142, 95% confidence interval 1.290-13.306, P = 0.0344) were independent predictors for overall survival.

CONCLUSION

The current study provides evidence that adding TRACE to neoadjuvant chemoradiotherapy can improve the pathological remission rate in LARC patients with acceptable toxicity. Given its promising effectiveness and safe profile, incorporating TRACE into the standard treatment strategy for patients with LARC should be considered.

Feasibility and safety of minimally invasive multivisceral resection for T4b rectal cancer: A 9-year review

BACKGROUND

Colorectal cancer is the third most common cancer and the second highest cause of cancer-related mortality worldwide. About 5%-10% of patients are diagnosed with locally advanced rectal cancer (LARC) on presentation. For LARC invading into other structures (i.e. T4b), multivisceral resection (MVR) and/or pelvic exenteration (PE) remains the only potential curative surgical treatment. MVR and/or PE is a major and complex surgery with high post-operative morbidity. Minimally invasive surgery (MIS) has been shown to improve short-term post-operative outcomes in other gastrointestinal malignancies, but there is little evidence on its use in MVR, especially so for robotic MVR.

AIM

To assess the feasibility and safety of minimally invasive MVR (miMVR), and compare post-operative outcomes between robotic and laparoscopic MVR.

METHODS

This is a single-center retrospective cohort study from 1st January 2015 to 31st March 2023. Inclusion criteria were patients diagnosed with cT4b rectal cancer and underwent MVR, or stage 4 disease with resectable systemic metastases. Patients who underwent curative MVR for locally recurrent rectal cancer, or metachronous rectal cancer were also included. Exclusion criteria were patients with systemic metastases with non-resectable disease. All patients planned for elective surgery were enrolled into the standard enhanced recovery after surgery pathway with standard peri-operative management for colorectal surgery. Complex surgery was defined based on technical difficulty of surgery (i.e. total PE, bladder-sparing prostatectomy, pelvic lymph node dissection or need for flap creation). Our primary outcomes were the margin status, and complication rates. Categorical values were described as percentages and analysed by the chi-square test. Continuous variables were expressed as median (range) and analysed by Mann-Whitney U test. Cumulative overall survival (OS) and recurrence-free survival (RFS) were analysed using Kaplan-Meier estimates with life table analysis. Log-rank test was performed to determine statistical significance between cumulative estimates. Statistical significance was defined as P < 0.05.

RESULTS

A total of 46 patients were included in this study [open MVR (oMVR): 12 (26.1%), miMVR: 36 (73.9%)]. Patients' American Society of Anesthesiologists score, body mass index and co-morbidities were comparable between oMVR and miMVR. There is an increasing trend towards robotic MVR from 2015 to 2023. MiMVR was associated with lower estimated blood loss (EBL) (median 450 vs 1200 mL, P = 0.008), major morbidity (14.7% vs 50.0%, P = 0.014), post-operative intra-abdominal collections (11.8% vs 50.0%, P = 0.006), post-operative ileus (32.4% vs 66.7%, P = 0.04) and surgical site infection (11.8% vs 50.0%, P = 0.006) compared with oMVR. Length of stay was also shorter for miMVR compared with oMVR (median 10 vs 30 d, P = 0.001). Oncological outcomes-R0 resection, recurrence, OS and RFS were comparable between miMVR and oMVR. There was no 30-d mortality. More patients underwent robotic compared with laparoscopic MVR for complex cases (robotic 57.1% vs laparoscopic 7.7%, P = 0.004). The operating time was longer for robotic compared with laparoscopic MVR [robotic: 602 (400-900) min, laparoscopic: Median 455 (275-675) min, P < 0.001]. Incidence of R0 resection was similar (laparoscopic: 84.6% vs robotic: 76.2%, P = 0.555). Overall complication rates, major morbidity rates and 30-d readmission rates were similar between laparoscopic and robotic MVR. Interestingly, 3-year OS (robotic 83.1% vs 58.6%, P = 0.008) and RFS (robotic 72.9% vs 34.3%, P = 0.002) was superior for robotic compared with laparoscopic MVR.

CONCLUSION

MiMVR had lower post-operative complications compared to oMVR. Robotic MVR was also safe, with acceptable post-operative complication rates. Prospective studies should be conducted to compare short-term and long-term outcomes between robotic vs laparoscopic MVR.

Contemporary management of rectal cancer

The management of rectal cancer has undergone significant changes over the past 50 years, and this has been associated with major improvements in overall outcomes and quality of life. From standardization of total mesorectal excision to refinements in radiation delivery and shifting of chemoradiotherapy treatment to favor a neoadjuvant approach, as well as the development of targeted chemotherapeutics, these management strategies have continually aimed to achieve locoregional and systemic control while limiting adverse effects and enhance overall survival. This article highlights evolving aspects of rectal cancer therapy including improved staging modalities, total neoadjuvant therapy, the role of short-course and more selective radiotherapy strategies, as well as organ preservation. We also discuss the evolving role of minimally invasive surgery and comment on lateral pelvic lymph node dissection.

Key message

Rectal cancer management is constantly evolving through refinements in radiation timing and delivery, modification of chemoradiotherapy treatment schedules, and increasing utilization of minimally invasive surgical techniques and organ preservation strategies. This manuscript aims to provide a synopsis of recent changes in the management of rectal cancer, highlighting contemporary modifications in neoadjuvant approaches and surgical management to enhance the knowledge of surgeons who care for this challenging population.

Quality of life and clinical outcomes in rectal cancer patients treated on a 1.5T MR-Linac within the MOMENTUM study

Background and purpose

This study assessed quality of life (QoL) and clinical outcomes in rectal cancer patients treated with magnetic resonance (MR) guided short-course radiation therapy (SCRT) on a 1.5 Tesla (T) MR-Linac during the first 12 months after treatment.

Materials and methods

Rectal cancer patients treated with 25 Gy SCRT in five fractions with curative intent in the Netherlands (2019-2022) were identified in MOMENTUM (NCT04075305). Toxicity (CTCAE v5) and QoL (EORTC QLQ-C30 and -CR29) was primarily analyzed in patients without metastatic disease (M0) and no other therapies after SCRT. Patients who underwent tumor resection were censored from surgery. A generalized linear mixed-model was used to investigate clinically meaningful (≥10) and significant (P < 0.05) QoL changes. Clinical and pathological complete response (cCR and pCR) rates were calculated in patients in whom response was documented.

Results

A total of 172 patients were included, of whom 112 patients were primarily analyzed. Acute and late radiation-induced high-grade toxicity were reported in one patient, respectively. CCR was observed in 8/64 patients (13 %), 14/37 patients (38 %) and 13/16 patients (91 %) at three, six and twelve months; pCR was observed in 3/69 (4 %) patients. After 12 months, diarrhea (mean difference [MD] -17.4 [95 % confidence interval [CI] -31.2 to -3.7]), blood and mucus in stool (MD -31.1 [95 % CI -46.4 to -15.8]), and anxiety (MD -22.4 [95 % CI -34.0 to -10.9]) were improved.

Conclusion

High-field MR-guided SCRT for the treatment of patients with rectal cancer is associated with improved disease-related symptom management and functioning one year after treatment.

A pilot study on the safety and efficacy of neoadjuvant chemo‑adoptive immunotherapy for locally advanced rectal cancer

The safety and efficacy of combination therapy of immune cell therapy and chemotherapy [chemo-adoptive immunotherapy (CAIT)] for patients with stage IV or recurrent colorectal cancer have been reported. In the present study, the safety and efficacy of neoadjuvant CAIT were investigated for preoperative therapy of locally advanced rectal cancer. The study included patients with cT3/T4 or cN (+) rectal adenocarcinoma scheduled for curative surgery. Six patients who consented to participate in the current study were selected as subjects. Neoadjuvant CAIT involves administration of activated autologous lymphocytes, αβ T cells, and mFOLFOX6 every 2 weeks for six courses, followed by surgery 4-6 weeks thereafter. Common Terminology Criteria for Adverse Events grade 3 neutropenia was observed in one patient. Neoadjuvant CAIT and curative surgery were performed on all the patients. The confirmed response rate was 67%. Downstaging was confirmed in five patients (83%). Regarding histological effects, two patients were grade 1a and four were grade 2. Regarding immunological reactions, both CD4+ and CD8+ T cell infiltration rates increased after treatment in three patients on tumor-infiltrating lymphocyte (TIL) analysis. In peripheral blood analysis, the total lymphocyte count was maintained in all patients, and the CD8+ T cell count increased by ≥3 times on the pretreatment count in two patients but may not be associated with changes in TILs. During the median postoperative follow-up duration of 24 months, liver and lung metastases occurred in one patient, but all patients survived. In conclusion, neoadjuvant CAIT (αβ T cells + mFOLFOX6) can be safely administered for the treatment of advanced rectal cancer. Verification of the efficacy of comprehensive immune cell therapy, especially the induction of antitumor immunity for the prevention of recurrence, will be maintained. The current study is registered with the Japan Registry of Clinical Trials (jRCT; ID, jRCTc030190248; January 21, 2019).

Knockdown of hCINAP sensitizes colorectal cancer cells to ionizing radiation

Colorectal cancer (CRC) poses a significant challenge in terms of treatment due to the prevalence of radiotherapy resistance. However, the underlying mechanisms responsible for radio-resistance in CRC have not been thoroughly explored. This study aimed to shed light on the role of human coilin interacting nuclear ATPase protein (hCINAP) in radiation-resistant HT-29 and SW480 CRC cells (HT-29-IR and SW480-IR) and investigate its potential implications. Firstly, radiation-resistant CRC cell lines were established by subjecting HT-29 and SW480 cells to sequential radiation exposure. Subsequent analysis revealed a notable increase in hCINAP expression in radiation-resistant CRC cells. To elucidate the functional role of hCINAP in radio-resistance, knockdown experiments were conducted. Remarkably, knockdown of hCINAP resulted in an elevation of reactive oxygen species (ROS) generation upon radiation treatment and subsequent activation of apoptosis mediated by mitochondria. These observations indicate that hCINAP depletion enhances the radiosensitivity of CRC cells. Conversely, when hCINAP was overexpressed, it was found to enhance the radio-resistance of CRC cells. This suggests that elevated hCINAP expression contributes to the development of radio-resistance. Further investigation revealed an interaction between hCINAP and ATPase family AAA domain containing 3A (ATAD3A). Importantly, ATAD3A was identified as an essential factor in hCINAP-mediated radio-resistance. These findings establish the involvement of hCINAP and its interaction with ATAD3A in the regulation of radio-resistance in CRC cells. Overall, the results of this study demonstrate that upregulating hCINAP expression may improve the survival of radiation-exposed CRC cells. Understanding the intricate molecular mechanisms underlying hCINAP function holds promise for potential strategies in targeted radiation therapy for CRC. These findings emphasize the importance of further research to gain a comprehensive understanding of hCINAP's precise molecular mechanisms and explore its potential as a therapeutic target in overcoming radio-resistance in CRC. By unraveling the complexities of hCINAP and its interactions, novel therapeutic approaches may be developed to enhance the efficacy of radiation therapy and improve outcomes for CRC patients.

Is radiotherapy necessary for upper rectal cancer underwent curative resection? A retrospective study of 363 patients

BACKGROUND

To investigate the impact of radiotherapy (RT) on recurrence and survival in patients with locally advanced upper rectal cancer underwent curative resection.

METHODS

363 locally advanced upper rectal cancer cases were identified from the database of our hospital from 2010 to 2018. All patients underwent curative resection and had the lower margin of the tumor located 10-15 cm from the anal verge, among them, 69 patients received pre- or post-operative radiotherapy and 294 patients without. Local control and survivals were compared, and stratification grouping based on European Society for Medical Oncology risk factors were further compared. 1:2 propensity score matching analysis was used to reduce the impact of confounding factors.

RESULTS

There were 207 patients after 1:2 matching (RT group:non-RT group = 69:138). The 5-year overall survival (OS) of the RT group and non-RT group after matching was 84.1% and 80.9%, respectively(P = 0.440); the 5-year local recurrence-free survival (LRFS) was 96.5% and 94.7%, respectively(P = 0.364); the 5-year distant metastasis-free survival (DMFS) was 76.8% and 76.9%, respectively(P = 0.531). Subgroup analysis showed that radiotherapy could not significantly improve the overall survival, local recurrence, and distant metastasis with or without poor prognostic features. In the high-risk subgroup, the 5-year OS was 76.9% and 79.6% for patients treated with radiotherapy and without (P = 0.798), LRFS was 94.8% and 94.2%, respectively (P = 0.605), DMFS 68.7% and 74.7%, respectively (P = 0.233).

CONCLUSIONS

Our results suggest that radiotherapy could not improve local control and survival for locally advanced upper rectal cancer patients underwent curative resection, even in the cases with poor prognostic features.

Adoption of Total Neoadjuvant Therapy in the Treatment of Locally Advanced Rectal Cancer

Local and metastatic recurrence are primary concerns following the treatment of locally advanced rectal cancer (LARC). Chemoradiation (CRT) can reduce the local recurrence rates and has subsequently moved to the neoadjuvant setting from the adjuvant setting. Pathological complete response (pCR) rates have also been noted to be greater in patients treated with neoadjuvant CRT prior to surgery. The standard approach to treating LARC would often involve CRT followed by surgery and optional adjuvant chemotherapy and remained the treatment paradigm for almost two decades. However, patients were often unable to complete adjuvant chemotherapy due to a decreased tolerance of chemotherapy following surgery, which led to upfront treatment with both CRT and chemotherapy, and total neoadjuvant therapy, or TNT, was created. The efficacy outcomes of local recurrence, disease-free survival, and pCR have improved in patients receiving TNT compared to the standard approach. Additionally, more recent data suggest a possible improvement in overall survival as well. Patients with a complete clinical response following TNT have the opportunity for watch-and-wait surveillance, allowing some patients to undergo organ preservation. Here, we discuss the clinical trials and studies that led to the adoption of TNT as the standard of care for LARC, with the possibility of watch-and-wait surveillance for patients achieving complete responses. We also review the possibility of overtreating some patients with LARC.

Lateral Pelvic Nodal Management and Patterns of Failure in Patients Receiving Short-Course Radiation for Locally Advanced Rectal Cancer

BACKGROUND

Management of lateral pelvic lymph nodes in locally advanced rectal cancer is controversial, with limited data indicating the optimal approach. In addition, no data exist regarding the treatment of lateral nodes in the setting of short-course radiation and nonoperative intent.

OBJECTIVE

To evaluate a novel approach incorporating simultaneous integrated boost to suspicious lateral nodes.

DESIGN

A retrospective study.

SETTING

This study was conducted at a large tertiary referral center.

PATIENTS

Patients treated with radiation therapy and consolidation chemotherapy were included. All primary tumors underwent biopsy confirmation and disease staging with pelvic MRI.

INTERVENTIONS

Primary tumors were biopsy proven and staged with pelvic MRI. A subset of lateral pelvic lymph node patients received a simultaneous integrated boost of 35 Gy in 5 fractions. Then, chemotherapy was administered, with the majority receiving modified folinic acid, fluorouracil, and oxaliplatin. Clinical partial response required total mesorectal excision.

MAIN OUTCOME MEASURES

Patterns of failure and survival analyses by subgroup were assessed. Outcomes based on receipt of radiation were compared across node status.

RESULTS

Between January 2017 and January 2022, 155 patients were treated with short-course chemotherapy, with 121 included in the final analysis. Forty-nine percent of patients underwent nonoperative management. The median follow-up was 36 months and the median age was 58 years. Thirty-eight patients (26%) had positive lateral pelvic lymph nodes. Comparing lateral node status, progression-free survival was significantly worse for patients with positive disease ( p < 0.001), with a trend for worse overall survival. Receipt of nodal boost in patients with lateral nodes resulted in meaningful locoregional control. Nodal boost did not contribute to additional acute or late GI toxicity.

LIMITATIONS

Limitations include retrospective nature and lack of lateral node pathology; however, a thorough radiographic review was performed.

CONCLUSIONS

Lateral node-positive rectal cancer is correlated with worse oncologic outcomes and higher locoregional failure. Boost to clinically positive lateral nodes is a safe approach in the setting of short course radiation and in those receiving nonoperative intent. See Video Abstract.

MANEJO DE LOS GANGLIOS PLVICOS LATERALES Y PATRONES DE FALLA EN PACIENTES QUE RECIBEN RADIACIN DE CICLO CORTO PARA EL CNCER DE RECTO LOCALMENTE AVANZADO

ANTECEDENTES:El manejo de los ganglios linfáticos pélvicos laterales en el cáncer de recto localmente avanzado es controvertido, con datos limitados que indiquen el abordaje óptimo. Además, no existen datos sobre el tratamiento de los ganglios linfáticos laterales en el contexto de la radiación de curso corto y la intención no operatoria.OBJETIVO:Evaluamos un enfoque novedoso que incorpora sobreimpresión integrada simultánea (SIB) a los linfonodos laterales sospechosos.DISEÑO:Este fue un estudio retrospectivo.ESCENARIO:Este estudio se realizó en un gran centro de referencia terciario.PACIENTES:Se incluyeron pacientes tratados con radiación y quimioterapia de consolidación. Todos los tumores primarios se confirmaron mediante biopsia y la enfermedad se estadificó con resonancia magnética pélvica.INTERVENCIONES:Los tumores primarios se confirmaron mediante biopsia y se estadificaron con RM pélvica. Un subconjunto de pacientes con linfonodos pélvicos laterales (LPLN) recibió SIB a 35 Gy en 5 fracciones. Luego, se administró quimioterapia y la mayoría recibió mFOLFOX. La respuesta clínica parcial requirió la escisión total del mesorrecto.PRINCIPALES MEDIDAS DE RESULTADO:Se evaluaron los patrones de fracaso y los análisis de supervivencia por subgrupo. Los resultados basados en el esquema de radiación se compararon según el estado de los ganglios.RESULTADOS:Entre enero de 2017 y enero de 2022, 155 pacientes fueron tratados con ciclo corto y quimioterapia con 121 incluidos en el análisis final. El 49% se sometió a manejo no operatorio. La mediana de seguimiento fue de 36 meses y la mediana de edad fue de 58 años. 38 pacientes (26%) tuvieron LPLN positivos. Comparando el estado de los ganglios laterales, la supervivencia libre de progresión fue significativamente peor para los pacientes con LPLN positiva ( p < 0,001) con una tendencia a una peor supervivencia global. La recepción de refuerzo nodal en pacientes con nodos laterales dio como resultado un control locorregional significativo. La sobreimpresión ganglionar no contribuyó a la toxicidad GI aguda o tardía adicional.LIMITACIONES:Las limitaciones incluyeron la naturaleza retrospectiva y la falta de patología de los ganglios linfáticos laterales; sin embargo, se realizó una revisión radiográfica exhaustiva.CONCLUSIONES:El cáncer de recto con ganglio lateral positivo se correlaciona con peores resultados oncológicos y mayor fracaso locorregional. La sobreimpresión a los ganglios laterales clínicamente positivos es un enfoque seguro en el contexto de un curso corto y en aquellos que siguen un manejo no operatorio. (Traducción-Dr. Felipe Bellolio ).

Current perspectives on the management of lateral pelvic lymph nodes in rectal cancer

Significant controversies exist with regards to the optimal management of lateral pelvic lymph nodes metastases (mLLN) in patients with low rectal cancer. The differing views held by Japanese and Western clinicians on the management of mLLN have been well documented. However, the adequacy of pelvic lymph node dissection (PLND) or neoadjuvant chemoradiation (NACRT) alone in addition to total mesorectal excision (TME) have recently come into question, due to the relatively high incidence of lateral local recurrences following PLND and TME, or NACRT and TME alone. Recently, a more selective approach to PLND has been suggested, involving a combination of neoadjuvant therapy, followed by PLND only to patients in whom the oncological benefit is likely to outweigh the risk of potential adverse events. A number of studies have attempted to retrospectively identify certain nodal characteristics on preoperative imaging, such as nodal size, appearance, and size reduction following neoadjuvant therapy. However, no consensus has been reached regarding the optimal criteria for a selective approach to PLND, partly due to the heterogeneity and retrospective nature of most of these studies. This review aims to provide an overview of recent evidence with regards to the diagnostic challenges, considerations for, and outcomes of the current management strategies for mLLN in rectal cancer patients.

Immunotherapy in rectal cancer patients-a propensity score matched analysis of the National Cancer Database

BACKGROUND

Rectal cancer patients with microsatellite instability (MSI-H) are candidates for immunotherapy. However, there is little evidence on its effect on overall survival (OS).

METHODS

Retrospective analysis of stage II-IV rectal adenocarcinoma patients in the National Cancer Database (NCDB) between 2010 and 2019. Propensity score matching was adjusted for baseline and treatment confounders. The cohort was divided into patients who received immunotherapy and matched controls. The primary outcome was OS.

RESULTS

5175/206,615 (2.5%) patients with rectal adenocarcinoma underwent immunotherapy. These patients were younger (58 vs 62 years; p < 0.001), more often male (64.4% vs 61.7%; p < 0.001), were more likely to have private insurance (50.8% vs 43.4%; p < 0.001), more metastatic disease at presentation (clinical TNM stage IV-80.8% vs 23.3%; p < 0.001), presented with larger tumors (median: 5 cm vs. 4.2 cm; p < 0.001) and less often underwent surgery (33.7% vs. 69.9%; p < 0.001), radiation therapy (21.5% vs 57.4%; p < 0.001), and standard chemotherapy (38.1% vs 61%; p < 0.001) than controls. After matching, 488 patients were in each group. OS was significantly shorter in the immunotherapy group (mean survival: 56.4 months (95% CI: -53.03-59.86)) compared to controls (mean survival: 70.5 months (95% CI: -66.15-74.92) (p = 0.004)). Cox regression analysis of factors associated with OS demonstrated that immunotherapy was associated with increased mortality (HR 2.16; 95% CI: 2.09-2.24; p < 0.001). After clinical staging stratification, immunotherapy was associated with improved OS in stage IV (HR 0.91, 95% CI: 0.88-0.95; p < 0.001) but lower survival in stage II (HR 2.38; 95% CI: 2.05-2.77; p < 0.001) and stage III (HR 2.43; 95% CI: 2.18-2.7; p < 0.001) patients.

CONCLUSION

Immunotherapy showed modest increase in OS in stage IV metastatic rectal cancer. OS was significantly lower in stage II-III disease treated with immunotherapy.

Quality of Surgical Outcome Reporting in Randomised Clinical Trials of Multimodal Rectal Cancer Treatment: A Systematic Review

INTRODUCTION

Randomised controlled trials (RCTs) continue to provide the best evidence for treatment options, but the quality of reporting in RCTs and the completeness rate of reporting of surgical outcomes and complication data vary widely. The aim of this study was to measure the quality of reporting of the surgical outcome and complication data in RCTs of rectal cancer treatment and whether this quality has changed over time.

METHODS

Eligible articles with the keywords ("rectal cancer" OR "rectal carcinoma") AND ("radiation" OR "radiotherapy") that were RCTs and published in the English, German, Polish, or Italian language were identified by reviewing all abstracts published from 1982 through 2022. Two authors independently screened and analysed all studies. The quality of the surgical outcome and complication data was assessed based on fourteen criteria, and the quality of RCTs was evaluated based on a modified Jadad scale. The primary outcome was the quality of reporting in RCTs and the completeness rate of reporting of surgical results and complication data.

RESULTS

A total of 340 articles reporting multimodal therapy outcomes for 143,576 rectal cancer patients were analysed. A total of 7 articles (2%) met all 14 reporting criteria, 13 met 13 criteria, 27 met from 11 to 12 criteria, 36 met from 9 to 10 criteria, 76 met from 7 to 8 criteria, and most articles met fewer than 7 criteria (mean 5.5 criteria). Commonly underreported criteria included complication severity (15% of articles), macroscopic integrity of mesorectal excision (17% of articles), length of stay (18% of articles), number of lymph nodes (21% of articles), distance between the tumour and circumferential resection margin (CRM) (26% of articles), surgical radicality according to the site of the primary tumour (R0 vs. R1 + R2) (29% of articles), and CRM status (38% of articles).

CONCLUSION

Inconsistent surgical outcome and complication data reporting in multimodal rectal cancer treatment RCTs is standard. Standardised reporting of clinical and oncological outcomes should be established to facilitate comparing studies and results of related research topics.

Essential anatomy for lateral lymph node dissection

In Western countries, the gold-standard therapeutic strategy for rectal cancer is preoperative chemoradiotherapy (CRT) following total mesorectal excision (TME), without lateral lymph node dissection (LLND). However, preoperative CRT has recently been reported to be insufficient to control lateral lymph node recurrence in cases of enlarged lateral lymph nodes before CRT, and LLND is considered necessary in such cases. We performed a literature review on aspects of pelvic anatomy associated with rectal surgery and LLND, and then combined this information with our experience and knowledge of pelvic anatomy. In this review, drawing upon research using a 3-dimensional anatomical model and actual operative views, we aimed to clarify the essential anatomy for LLND. The LLND procedure was developed in Asian countries and can now be safely performed in terms of functional preservation. Nonetheless, the longer operative time, hemorrhage, and higher complication rates with TME accompanied by LLND than with TME alone indicate that LLND is still a challenging procedure. Laparoscopic or robotic LLND has been shown to be useful and is widely performed; however, without a sufficient understanding of anatomical landmarks, misrecognition of vessels and nerves often occurs. To perform safe and accurate LLND, understanding the landmarks of LLND is essential.

The "Watch and Wait" Method After Chemoradiotherapy for Rectal Cancer Requiring Abdominoperineal Resection

The present study examined the therapeutic effects of preoperative neoadjuvant chemoradiation therapy (NACRT) and predictive factors for complete clinical remission, compared the prognosis and costs of abdominoperineal resection (APR) and the "watch and wait" method (WW), and evaluated the usefulness of WW. In our department, patients with stage II-III lower rectal cancer requiring APR receive NACRT. NACRT was performed as a preoperative treatment (52 Gy + S-1: 80-120 mg/day × 25 days). Eight weeks after the completion of NACRT, rectal examination, endoscopic, computed tomography, and magnetic resonance imaging findings were evaluated to assess its therapeutic effects. APR was indicated for patients in whom endoscopic findings suggested a residual tumor in which a deep ulcer or marginal swelling remained or lymph node metastasis. However, WW was selected for patients who refused APR after informed consent was obtained. In the APR and WW groups, 5- and 20-year treatment costs after CRT were calculated using the Medical Fee Points of Japan in 2020. No significant differences were observed in 3-year disease-free survival rates for either parameter between the two groups. Regarding expenses, treatment costs were lower in the WW group than in the APR group. Organ preservation using active surveillance with CRT for rectal cancer requiring APR is feasible with the achievement of endoluminal complete remission.

Radiotherapy in the preoperative neoadjuvant treatment of locally advanced rectal cancer

Radiotherapy and chemotherapy are effective treatments for patients with locally advanced rectal cancer (LARC) and can significantly improve the likelihood of R0 resection. Radiotherapy can be used as a local treatment to reduce the size of the tumor, improve the success rate of surgery and reduce the residual cancer cells after surgery. Early chemotherapy can also downgrade the tumor and eliminate micrometastases throughout the body, reducing the risk of recurrence and metastasis. The advent of neoadjuvant concurrent radiotherapy (nCRT) and total neoadjuvant treatment (TNT) has brought substantial clinical benefits to patients with LARC. Even so, given increasing demand for organ preservation and quality of life and the disease becoming increasingly younger in its incidence profile, there is a need to further explore new neoadjuvant treatment options to further improve tumor remission rates and provide other opportunities for patients to choose watch-and-wait (W&W) strategies that avoid surgery. Targeted drugs and immunologic agents (ICIs) have shown good efficacy in patients with advanced rectal cancer but have not been commonly used in neoadjuvant therapy for patients with LARC. In this paper, we review several aspects of neoadjuvant therapy, including radiation therapy and chemotherapy drugs, immune drugs and targeted drugs used in combination with neoadjuvant therapy, with the aim of providing direction and thoughtful perspectives for LARC clinical treatment and research trials.

Treatment response prediction of neoadjuvant chemotherapy for rectal cancer by deep learning of colonoscopy images

In current clinical practice, several treatment methods, including neoadjuvant therapy, are being developed to improve overall survival or local recurrence rates for locally advanced rectal cancer. The response to neoadjuvant therapy is usually evaluated using imaging data collected before and after preoperative treatment or postsurgical pathological diagnosis. However, there is a need to accurately predict the response to preoperative treatment before treatment is administered. The present study used a deep learning network to examine colonoscopy images and construct a model to predict the response of rectal cancer to neoadjuvant chemotherapy. A total of 53 patients who underwent preoperative chemotherapy followed by radical resection for advanced rectal cancer at the Osaka University Hospital between January 2011 and August 2019 were retrospectively analyzed. A convolutional neural network model was constructed using 403 images from 43 patients as the learning set. The diagnostic accuracy of the deep learning model was evaluated using 84 images from 10 patients as the validation set. The model demonstrated a sensitivity, specificity, accuracy, positive predictive value and area under the curve of 77.6% (38/49), 62.9% (22/33), 71.4% (60/84), 74.5% (38/51) and 0.713, respectively, in predicting a poor response to neoadjuvant therapy. Overall, deep learning of colonoscopy images may contribute to an accurate prediction of the response of rectal cancer to neoadjuvant chemotherapy.

Risk factors and clinical characteristics of rectal cancer recurrence after radical surgical treatment

<b><br>Introduction:</b> Recurrence of rectal cancer affects from 4% to even 50% of patients after surgical treatment. The incidence may be influenced by numerous factors depending on the patient, the characteristics of the tumor and the type and quality of the surgical technique used.</br> <b><br>Aim:</b> The aim of this study was to assess the clinical characteristics of rectal cancer recurrence, identify potential risk factors and role of patient surveillance after primary resection of rectal cancer.</br> <b><br>Materials and methods:</b> The study comprised patients operated on due to recurrence of rectal cancer at the Department of General and Colorectal Surgery of Medical University of Lodz between 2014 and 2020, who were in the follow-up program at the hospital's outpatient clinic after the primary surgery. Risk factors for disease recurrence were sought by analyzing the characteristics of the primary tumor, treatment history and postoperative care.</br> <b><br>Results:</b> Twenty-nine patients were included in the study, the majority (51.7%) of the patients were men. The largest group was represented by patients with stage II and III disease. The most frequently performed primary surgery was low anterior resection (LAR) (62.8%). 35% of patients received neoadjuvant treatment prior to primary surgery. We demonstrated that the lack of neoadjuvant treatment before primary surgery increases the risk of cancer recurrence nine times. Higher stage of disease at the point of primary surgery is associated with nearly seven times the risk of recurrence compared to stage I disease.</br> <b><br>Conclusions:</b> Optimal preoperative staging, reasonable neoadjuvant treatment, proper surgical technique and precise follow-up regimen are essential for further improvement of rectal cancer outcomes.</br>.

Advances in rectal cancer: Real-world evidence suggests limited gains in prognosis for elderly patients

BACKGROUND

Rectal cancer treatment has improved considerably due to the introduction of total meso-rectal excision, radio-chemotherapy, and high-resolution imaging. The aim of this observational cohort study was to quantify the effectiveness of these advances using high-quality data from a representative cohort of patients.

METHODS

20 281 non-metastasized cases retrieved from the Munich Cancer Registry database were divided into three time periods corresponding to before (1988-1997), partial (1998-2007), and full implementation (2008-2019) of clinical advances. Early-onset (<50 yrs.), middle-aged, elderly patient subgroups (> 70 yrs.) were compared. The overall effectiveness of evidence-based guideline adherence was also examined.

RESULTS

Median survival improved by 1.5 yrs. from the first to the last time period. Relative survival increased from 74.9% (5-yr 95%CI[73.3 - 76.6]) to 79.2% (95%CI[77.8 - 80.5]). The incidence of locoregional recurrences was reduced dramatically by more than half (5-yr 17.7% (95%CI[16.5 - 18.8]); 6.7% (95%CI[6.1 - 7.3])). Gains in 5-yr relative survival were limited to early-onset and middle-aged patients with no significant improvement seen in elderly patients (Female 68.6% [63.9 - 73.3] to 67.6% [64.0 - 71.2]; Male 71.7% [65.9 - 77.4] to 74.0% [70.8 - 77.2]).

CONCLUSIONS

Real-world evidence suggests that recent treatment advances have lead to an increase in prognosis for rectal cancer patients. However, more effort should be made to improve the implementation of new developments in elderly patients. Especially considering, that these cases represent a growing majority of diagnosed patients.

Prospective analysis of impact of learning curve in robotic-assisted rectal surgery in the high-volume Indian tertiary care centre

Background

Minimally invasive surgery in rectal cancer has gained prominence owing to its various advantages in surgical outcomes. Due to rapid adoption of robotics in rectal surgery, we intended to assess the pace in which surgeons gain proficiency using cumulative summation (CUSUM) technique in learning curve.

Materials and Methods

This was a prospective study of 262 rectal cancer cases who underwent robotic-assisted low anterior resection and abdominoperineal resection (RA-LAR and RA-APR). Parameters considered for the study were console time, docking time, lymph nodal yield, total operative time and post-operative outcomes. We used Manipal technique of port placements and modified centroside docking for the procedure.

Results

The mean age of our study was 46.62 ± 5.7 years, the mean body mass index (BMI) was 31.51 ± 3.2 kg/m2. 215 (82.06%) underwent RA-LAR and 47 (17.93%) underwent RA-APR. 2.67% of cases required to open during our initial period. We had three phases of learning curve, initial phase (11th case), plateau phase (29th case) and then phases of mastery (30th case onwards). Our mean total operative time reduced from 5.5 to 3.5 h (210 ± 8.2 min), console time from 4.5 to 2.9 h (174 ± 4.5 min) and docking time from 15 to 9 ± 1 min from 30th case onwards.

Conclusion

RA surgeries for rectal cancer have got good oncological and functional outcomes in high BMI, male pelvis and low rectal cancers. Learning curve can be shortened with constant self-auditing of the surgeon and team with each surgeries performed, reviewing the steps and by improving techniques.

Risk factors associated with low anterior resection syndrome: a cross-sectional study

PURPOSE

Oncological outcomes following rectal cancer surgery have improved significantly over recent decades with lower recurrences and longer overall survival. However, many of the patients experienced low anterior resection syndrome (LARS). This study identified the prevalence and risk factors associated with the development of LARS.

METHODS

This cross-sectional study involved patients who were diagnosed with rectal cancer and had undergone sphincter-preserving low anterior resection from January 2011 to December 2020. Upon clinic follow-up, patients were asked to complete an interviewed based questionnaire (LARS score) designed to assess bowel dysfunction after rectal cancer surgery.

RESULTS

Out of 76 patients, 25 patients (32.9%) had major LARS, 10 patients (13.2%) had minor LARS, and 41 patients (53.9%) had no LARS. The height of tumor from anal verge showed an association with the development of major LARS (P=0.039). Those patients with less than 8 cm tumor from anal verge had an increased risk of LARS by 3 times compared to those with 8 cm and above (adjusted odds ratio, 3.11; 95% confidence interval, 1.06-9.13).

CONCLUSION

Results from our study show that low tumor height was a significant risk factor that has a negative impact on bowel function after surgery. The high prevalence of LARS emphasizes the need for study regarding risk factors and the importance of understanding the pathophysiology of LARS, in order for us to improve patient bowel function and quality of life after rectal cancer surgery.

Lateral lymph node involvement presents another challenge in rectum cancer in the age of neoadjuvant chemoradiotherapy + total mesorectal excision: an evaluation of survival outcomes

PURPOSE

In the last decades, total mesorectal excision (TME) and neoadjuvant chemoradiotherapy (nCRT) have produced an undeniable improvement in the treatment of rectal cancer. However, local recurrence is still an important problem, and the effect of lateral lymph node (LLN) involvement on local recurrence is a controversial issue. The aim of this study was to investigate the effects of LLN status on local recurrence and survival in rectal cancers treated with nCRT + TME.

METHODS

Clinical features, pre- and post-nCRT lateral pelvic region imaging, long-term local recurrence, and the survival outcomes of 114 patients who underwent nCRT + TME for rectal cancer were evaluated.

RESULTS

On MRI before nCRT, 20 (17.5%) patients had lateral lymph nodes (LLN+), and 94 (82.5%) patients had no lymph nodes in the lateral pelvic compartments (LLN-). Local recurrences at 1 year in LLN+ and LLN- patients were 3 (15.8%) and 2 (2.3%), respectively (p=0.039). Five-year local recurrence-free survival rates and the mean duration of recurrence-free survival in LLN+ and LLN- patients were 56.2%, 42.6 months, and 87.3% 66.9 months, respectively (p=0.001). Disease-free survival and overall survival were shorter in LLN+ patients, but the difference was not statistically significant (p=0.096 and p=0.46, respectively). In the multivariate analysis, LLN involvement was determined to be an independent risk factor for local recurrence-free survival (Hazard Ratio 4.54, p=0.003).

CONCLUSION

Lateral lymph node involvement causes local recurrence to remain high after nCRT + TME. LLN status should be considered in treatment planning. Further studies are needed to define precise criteria for LLN involvement and the effect of LLND on local recurrence and survival.

Rectal cancer lexicon 2023 revised and updated consensus statement from the Society of Abdominal Radiology Colorectal and Anal Cancer Disease-Focused Panel

The Society of Abdominal Radiology's Colorectal and Anal Cancer Disease-Focused Panel (DFP) first published a rectal cancer lexicon paper in 2019. Since that time, the DFP has published revised initial staging and restaging reporting templates, and a new SAR user guide to accompany the rectal MRI synoptic report (primary staging). This lexicon update summarizes interval developments, while conforming to the original lexicon 2019 format. Emphasis is placed on primary staging, treatment response, anatomic terminology, nodal staging, and the utility of specific sequences in the MRI protocol. A discussion of primary tumor staging reviews updates on tumor morphology and its clinical significance, T1 and T3 subclassifications and their clinical implications, T4a and T4b imaging findings/definitions, terminology updates on the use of MRF over CRM, and the conundrum of the external sphincter. A parallel section on treatment response reviews the clinical significance of near-complete response and introduces the lexicon of "regrowth" versus "recurrence". A review of relevant anatomy incorporates updated definitions and expert consensus of anatomic landmarks, including the NCCN's new definition of rectal upper margin and sigmoid take-off. A detailed review of nodal staging is also included, with attention to tumor location relative to the dentate line and locoregional lymph node designation, a new suggested size threshold for lateral lymph nodes and their indications for use, and imaging criteria used to differentiate tumor deposits from lymph nodes. Finally, new treatment terminologies such as organ preservation, TNT, TAMIS and watch-and-wait management are introduced. This 2023 version aims to serve as a concise set of up-to-date recommendations for radiologists, and discusses terminology, classification systems, MRI and clinical staging, and the evolving concepts in diagnosis and treatment of rectal cancer.

Total neoadjuvant therapy with short-course radiotherapy Versus long-course neoadjuvant chemoradiotherapy in Locally Advanced Rectal cancer, Korean trial (TV-LARK trial): study protocol of a multicentre randomized controlled trial

BACKGROUND

For locally advanced rectal cancer (LARC), total neoadjuvant therapy (TNT) may enhance tumour response, reduce recurrence, and improve patient compliance compared to upfront surgery. Recent studies have shown that chemoradiotherapy (CRT) followed by consolidation chemotherapy leads to higher rate of pathologic complete response (pCR) than induction chemotherapy followed by CRT. However, an optimal TNT regimen that maximise the pCR rate and minimise toxicity has not been established. Therefore, the aim of this trial was to investigate whether preoperative short-course radiotherapy followed by chemotherapy with four cycles of CAPOX can double the pCR rate compared to a standard schedule of long-course preoperative CRT in patients with LARC.

METHODS

This is a multi-centre, prospective, open label, randomised controlled trial. Patients with clinical primary tumour stage 3 and higher or regional node-involved rectal cancer located within 10 cm from the anal verge were randomly assigned equally to short-course radiotherapy (25 Gy in 5 fractions over 1 week) followed by four cycles of CAPOX (intravenous oxaliplatin [130 mg/m2, once a day] on day 1 and capecitabine [1,000 mg/m2, twice a day] from days 1 to 14) (TNT) or CRT (50.4 Gy in 28 fractions over 5 weeks, concurrently with concomitant oral capecitabine 825 mg/m2 twice a day). After preoperative treatment, total mesorectal excision was performed 2-4 weeks in the TNT group and 6-10 weeks in the CRT group, followed by optional additional adjuvant chemotherapy. The primary endpoint is the pCR rate, and secondary endpoints include disease-related treatment failure, quality of life, and cost-effectiveness. Assuming a pCR rate of 28% and 15% in the TNT and CRT groups, respectively, and one-side alpha error rate of 0.025 and power of 80%, 348 patients will be enrolled considering 10% dropout rate.

DISCUSSION

The TV-LARK trial will evaluate the superiority of employed TNT regimen against the standard CRT regimen for patients with LARC. We aimed to identify a TNT regimen that will improve the pCR rate and decrease systemic recurrence in these patients.

TRIAL REGISTRATION

Cris.nih.go.kr ID: KCT0007169 (April 08, 2022). The posted information will be updated as needed to reflect the protocol amendments and study progress.

Radiation hematologic toxicity prediction for locally advanced rectal cancer using dosimetric and radiomics features

BACKGROUND

Hematologic toxicity (HT) is a common adverse tissue reaction during radiotherapy for rectal cancer patients, which may lead to various negative effects such as reduced therapeutic effect, prolonged treatment period and increased treatment cost. Therefore, predicting the occurrence of HT before radiotherapy is necessary but still challenging.

PURPOSE

This study proposes a hybrid machine learning model to predict the symptomatic radiation HT in rectal cancer patients using the combined demographic, clinical, dosimetric, and Radiomics features, and ascertains the most effective regions of interest (ROI) in CT images and predictive feature sets.

METHODS

A discovery dataset of 240 rectal cancer patients, including 145 patients with HT symptoms and a validation dataset of 96 patients (63 patients with HT) with different dose prescription were retrospectively enrolled. Eight ROIs were contoured on patient CT images to derive Radiomics features, which were then, respectively, combined with the demographic, clinical, and dosimetric features to classify patients with HT symptoms. Moreover, the survival analysis was performed on risky patients with HT in order to understand the HT progression.

RESULTS

The classification models in ROIs of bone marrow and femoral head exhibited relatively high accuracies (accuracy = 0.765 and 0.725) in the discovery dataset as well as comparable performances in the validation dataset (accuracy = 0.758 and 0.714). When combining the two ROIs together, the model performance was the best in both discovery and validation datasets (accuracy = 0.843 and 0.802). In the survival analysis test, only the bone marrow ROI achieved statistically significant performance in accessing risky HT (C-index = 0.658, P = 0.03). Most of the discriminative features were Radiomics features, and only gender and the mean dose in Irradvolume was involved in HT.

CONCLUSION

The results reflect that the Radiomics features of bone marrow are significantly correlated with HT occurrence and progression in rectal cancer. The proposed Radiomics-based model may help the early detection of radiotherapy induced HT in rectal cancer patients and thus improve the clinical outcome in future.

Total Neoadjuvant Treatment for Locally Advanced Rectal Cancer Patients: Where Do We Stand?

The therapeutic landscape in locally advanced rectal cancer (LARC) has undergone a significant paradigm shift in recent years with the rising adoption of total neoadjuvant treatment (TNT). This comprehensive approach entails administering chemotherapy and radiation therapy before surgery, followed by optional adjuvant chemotherapy. To establish and deliver the optimal tailored treatment regimen to the patient, it is crucial to foster collaboration among a multidisciplinary team comprising healthcare professionals from various specialties, including medical oncology, radiation oncology, surgical oncology, radiology, and pathology. This review aims to provide insights into the current state of TNT for LARC and new emerging strategies to identify potential directions for future research and clinical practice, such as circulating tumor-DNA, immunotherapy in mismatch-repair-deficient tumors, and nonoperative management.

Preoperative Treatment of Locally Advanced Rectal Cancer

BACKGROUND

Pelvic radiation plus sensitizing chemotherapy with a fluoropyrimidine (chemoradiotherapy) before surgery is standard care for locally advanced rectal cancer in North America. Whether neoadjuvant chemotherapy with fluorouracil, leucovorin, and oxaliplatin (FOLFOX) can be used in lieu of chemoradiotherapy is uncertain.

METHODS

We conducted a multicenter, unblinded, noninferiority, randomized trial of neoadjuvant FOLFOX (with chemoradiotherapy given only if the primary tumor decreased in size by <20% or if FOLFOX was discontinued because of side effects) as compared with chemoradiotherapy. Adults with rectal cancer that had been clinically staged as T2 node-positive, T3 node-negative, or T3 node-positive who were candidates for sphincter-sparing surgery were eligible to participate. The primary end point was disease-free survival. Noninferiority would be claimed if the upper limit of the two-sided 90.2% confidence interval of the hazard ratio for disease recurrence or death did not exceed 1.29. Secondary end points included overall survival, local recurrence (in a time-to-event analysis), complete pathological resection, complete response, and toxic effects.

RESULTS

From June 2012 through December 2018, a total of 1194 patients underwent randomization and 1128 started treatment; among those who started treatment, 585 were in the FOLFOX group and 543 in the chemoradiotherapy group. At a median follow-up of 58 months, FOLFOX was noninferior to chemoradiotherapy for disease-free survival (hazard ratio for disease recurrence or death, 0.92; 90.2% confidence interval [CI], 0.74 to 1.14; P = 0.005 for noninferiority). Five-year disease-free survival was 80.8% (95% CI, 77.9 to 83.7) in the FOLFOX group and 78.6% (95% CI, 75.4 to 81.8) in the chemoradiotherapy group. The groups were similar with respect to overall survival (hazard ratio for death, 1.04; 95% CI, 0.74 to 1.44) and local recurrence (hazard ratio, 1.18; 95% CI, 0.44 to 3.16). In the FOLFOX group, 53 patients (9.1%) received preoperative chemoradiotherapy and 8 (1.4%) received postoperative chemoradiotherapy.

CONCLUSIONS

In patients with locally advanced rectal cancer who were eligible for sphincter-sparing surgery, preoperative FOLFOX was noninferior to preoperative chemoradiotherapy with respect to disease-free survival. (Funded by the National Cancer Institute; PROSPECT ClinicalTrials.gov number, NCT01515787.).

Cost-Effectiveness Analysis: Selective Use of Neoadjuvant Chemoradiation in Locally Advanced Rectal Cancer

BACKGROUND

Locally advanced rectal cancer has high cure rates with trimodal therapy. Studies sparing neoadjuvant chemoradiation in selected patients show comparable outcomes.

OBJECTIVE

This study aimed to determine the cost-effectiveness of selective use of neoadjuvant chemoradiation in this population.

DESIGN

A cost-effectiveness analysis model compared selective and blanket use chemoradiation for locally advanced rectal cancer.

SETTINGS

Literature review, expert consensus, and a prospective database populated the model. Health care utilization costs were based on information from the Centers for Medicare and Medicaid Services.

PATIENTS

Adult patients with stage II and III rectal cancer were selected.

MAIN OUTCOMES MEASURES

Primary outcomes were cost, effectiveness in quality-adjusted disease-free life years, net monetary benefit, and incremental cost-effectiveness ratios in dollars per quality-adjusted disease-free life years. Base-case 5-year disease-free survival for both strategies was 65%. One-way sensitivity analysis found the probability of 5-year disease-free survival for selective ranged between 40% and 65%. Probabilistic sensitivity analysis assessed second-order variability.

RESULTS

Base-case 5-year disease-free survival demonstrated selective use is dominant with lower cost and higher quality-adjusted disease-free life years. For selective use, cost is $153,176, effectiveness is 2.71 quality-adjusted life years, and net monetary benefit is -$17,564 and for blanket use cost is $176,362, effectiveness is 2.64 quality-adjusted life years, and net monetary benefit is -$44,217. One-way sensitivity analysis shows selective use is dominant for disease-free survival above 61.25% and is preferred for disease-free survival above 53.7%. Probabilistic sensitivity analysis shows selective use is optimal in 88% of the iterations for a population of 10,000 patients.

LIMITATIONS

Model was based on data from the literature, prospective database, and expert consensus.

CONCLUSION

In a population of patients with locally advanced rectal cancer with base-case disease-free survival of 65%, selective use of neoadjuvant chemoradiation is the superior strategy as long as disease-free survival in this group remains above 53%. See Video Abstract at http://links.lww.com/DCR/C199.

ANLISIS DE COSTOEFECTIVIDAD USO SELECTIVO DE QUIMIORRADIACIN NEOADYUVANTE EN CNCER DE RECTO LOCALMENTE AVANZADO

ANTECEDENTES:El cáncer de recto localmente avanzado tiene altas tasas de curación con la terapia trimodal. Los estudios que evitan la quimiorradiación neoadyuvante en pacientes seleccionados muestran resultados comparables.OBJETIVO:Determinar la relación costo-efectividad del uso selectivo de quimiorradiación neoadyuvante en esta población.DISEÑO:Un modelo de análisis de costo-efectividad comparó la quimiorradiación selectiva y de uso general para el cáncer de recto localmente avanzado.AJUSTES:Revisión de literatura, consenso de expertos y una base de datos prospectiva poblaron el modelo. Los costos de utilización de la atención médica se basaron en los Centros de Servicios de Medicare y Medicaid.PACIENTES:Se seleccionaron pacientes adultos con cáncer de recto en estadio II y III.PRINCIPALES MEDIDAS DE RESULTADOS:Los resultados primarios fueron el costo, efectividad en años de vida sin enfermedad ajustados por calidad, el beneficio monetario neto y la relación costo-efectividad incremental en $/años de vida sin enfermedad ajustados por calidad. La supervivencia libre de enfermedad a 5 años del caso base para ambas estrategias fue del 65%. El análisis de sensibilidad unidireccional varió la probabilidad de supervivencia libre de enfermedad a 5 años para uso selectivo entre 40%-65%. El análisis de sensibilidad probabilístico evaluó la variabilidad de segundo orden.RESULTADOS:El caso base de 5 años de supervivencia libre de enfermedad demostró que el uso selectivo es dominante con menor costo y años de vida libre de enfermedad ajustados de mayor calidad. El costo, la efectividad y el beneficio monetario neto para el uso selectivo y general fueron ($153 176; 2,71 QALY; -$17 564) y ($176 362; 2,64 QALY; -$44 217). El análisis de sensibilidad unidireccional demostró que el uso selectivo es dominante para la supervivencia sin enfermedad por encima del 61,25% y se prefiere para la supervivencia sin enfermedad por encima del 53,7%. El análisis de sensibilidad probabilístico demostró que el uso selectivo es óptimo en el 88% de las iteraciones para una población de 10 000 pacientes.LIMITACIONES:Modelo basado en datos de literatura, base de datos prospectiva y consenso de expertos.CONCLUSIÓN:En una población de pacientes con cáncer de recto localmente avanzado con caso base de supervivencia libre de enfermedad del 65%, el uso selectivo de quimiorradiación neoadyuvante para el cáncer de recto localmente avanzado es la estrategia superior, siempre y cuando la supervivencia libre de enfermedad en este grupo se mantenga por encima del 53%. Consulte Video Resumen en http://links.lww.com/DCR/C199. (Traducción-Dr. Fidel Ruiz Healy).

Emerging Roles of Circulating Tumor DNA for Increased Precision and Personalization in Radiation Oncology

Recent breakthroughs in circulating tumor DNA (ctDNA) technologies present a compelling opportunity to combine this emerging liquid biopsy approach with the field of radiogenomics, the study of how tumor genomics correlate with radiotherapy response and radiotoxicity. Canonically, ctDNA levels reflect metastatic tumor burden, although newer ultrasensitive technologies can be used after curative-intent radiotherapy of localized disease to assess ctDNA for minimal residual disease (MRD) detection or for post-treatment surveillance. Furthermore, several studies have demonstrated the potential utility of ctDNA analysis across various cancer types managed with radiotherapy or chemoradiotherapy, including sarcoma and cancers of the head and neck, lung, colon, rectum, bladder, and prostate . Additionally, because peripheral blood mononuclear cells are routinely collected alongside ctDNA to filter out mutations associated with clonal hematopoiesis, these cells are also available for single nucleotide polymorphism analysis and could potentially be used to detect patients at high risk for radiotoxicity. Lastly, future ctDNA assays will be utilized to better assess locoregional MRD in order to more precisely guide adjuvant radiotherapy after surgery in cases of localized disease, and guide ablative radiotherapy in cases of oligometastatic disease.

Efficacy of hypofractionated preoperative chemoradiotherapy in rectal cancer

The efficacy and toxicity of hypofractionated preoperative chemoradiotherapy (HPCRT) combined with oral capecitabine was evaluated in patients with rectal cancer. HPCRT was delivered by intensity-modulated radiotherapy of either 33 Gy to the whole pelvis or 35 Gy in 10 fractions to the primary tumor and 33 Gy to the surrounding pelvis. Surgery was performed 4-8 weeks after HPCRT completion. Oral capecitabine was administered concurrently. A total of 76 patients were eligible for this study, and patient numbers in clinical stages I, II, III and IVA were 5, 29, 36 and 6, respectively. Tumor response, toxicity and survival were analyzed. A total of 9/76 patients (11.8%) achieved a pathological complete response. Sphincter preservation was achieved in 23/32 (71.9%) and 44/44 (100%) of patients with a distal extent from the anal verge of ≤5 and >5 cm, respectively. A total of 28/76 patients (36.8%) achieved tumor-downstaging and 25/76 (32.9%) achieved nodal (N)-downstaging. The 5-year disease-free survival (DFS) and overall survival rates were 76.5% and 90.6%, respectively. In the multivariate analysis for DFS, pathological N stage and lymphovascular space invasion were notable prognostic factors. A total of 6 patients in stage IVA underwent salvage treatments for lung or liver metastasis after HPCRT completion, and all 6 were alive at the last follow-up. Only 4 patients experienced grade 3 postoperative complications. No grade 4 toxicities were observed. HPCRT of 33 or 35 Gy in 10 fractions showed similar results to those of long-course fractionation. This fractionation scheme could be beneficial for patients with early stage disease, locally advanced rectal cancer, simultaneous distant metastasis requiring early intervention or for patients who wish to avoid multiple hospital visits.

Determining the optimal interval between neoadjuvant radiochemotherapy and surgery in rectal cancer: a retrospective cohort study

INTRODUCTION

In locally advanced rectal cancer, the optimal interval between completion of neoadjuvant radiochemotherapy (RT-ChT) and surgical resection remains unclear due to contradictory data on the benefits of extending this interval. Therefore, the aim of this retrospective study was to determine the impact of this interval on outcomes in patients treated for rectal cancer at our center.

METHODS

We retrospectively reviewed 382 consecutive patients treated for stage II/III rectal cancer between October 1, 2012, and December 31, 2017. We evaluated four different cut-off points (56, 63, 70, and 77 days) to determine which had the greatest impact on treatment outcomes.

RESULTS

The median time between completion of RT-ChT and surgery was 67.2 days (range, 28-294). Intervals > 8 weeks (56 days) were associated with worse therapeutic outcomes. Specifically, an interval ≥ 77 days was associated with a significant decrease in overall survival (OS; 84% vs. 70%; p = 0.004), which is why we selected this interval for the comparative analysis. Several outcome variables were significantly better in the short interval (< 77 days) group, including margin involvement (5.2% vs. 13.9%; p = 0.01), sphincter preservation (78% vs. 59.3%; p = 0.003), and distant dissemination (22.6% vs. 32.5%; p = 0.04). No significant between-group differences were found in complete/nearly complete response rates (19.2% vs. 24.4%; p = 0.3). Time to surgery was statistically significant on both the univariate and multivariate analyses.

CONCLUSIONS

Our findings suggest that surgery should not be delayed more than 8 weeks (56 days) after neoadjuvant treatment. An interval > 8 weeks should only be considered in patients who demonstrate a good response to neoadjuvant RT-ChT.

Diagnostic accuracy of endoscopy in determining rectal tumor proximity to the peritoneal reflection

PURPOSE

Treatment of invasive rectal adenocarcinoma is stratified into upfront surgery versus neoadjuvant chemoradiotherapy, in part, based on tumor distance from the anal verge (AV). This study examines the correlation between tumor distance measurements (endoscopic and MRI) and relationship to the anterior peritoneal reflection (aPR) on MRI.

METHODS

A single-center retrospective study was performed at a tertiary center accredited by the National Accreditation Program for Rectal Cancer (NAPRC). 162 patients with invasive rectal cancer were seen between October of 2018 and April of 2022. Sensitivity and specificity were determined for MRI and endoscopic measurements in their ability to predict tumor location relative to the aPR.

RESULTS

One hundred nineteen patients had tumors endoscopically and radiographically measured from the AV. Pelvic MRI characterized tumors as above (intraperitoneal) or at/straddles/below the aPR (extraperitoneal). True positives were defined as extraperitoneal tumors [Formula: see text] 10 cm. True negatives were defined as intraperitoneal tumors > 10 cm. Endoscopy was 81.9% sensitive and 64.3% specific in predicting tumor location with respect to the aPR. MRI was 86.7% sensitive and 92.9% specific. Utilizing a 12 cm cutoff, sensitivity of both modalities increased (94.3%, 91.4%) but specificity decreased (50%, 64.3%).

CONCLUSION

For locally invasive rectal cancers, tumor position relative to the aPR is an important factor in determining the role of neoadjuvant therapy. These results suggest endoscopic tumor measurements do not accurately predict tumor location relative to the aPR, and may lead to incorrect treatment stratification recommendation. When the aPR is not identified, MRI-reported tumor distance may be a better predictor of this relationship.

Challenges and Suggestions in the Management of Stomach and Colorectal Cancer in Uzbekistan: The Third Report of the Uzbekistan-Korea Oncology Consortium

In general, as the national standard of living and life expectancy of people increase, the health burden of cancer also increases. Prevention strategies, including the screening and investigation of the causes of cancer as well as the expansion of treatment infrastructure, are necessary. In this review, we discussed the management strategies for gastric and colorectal cancers in Uzbekistan. Gastrointestinal cancers can be significantly prevented by certain screening strategies such as endoscopic examination. Furthermore, as both cancer types are closely related to the eating habits and lifestyles of people in Uzbekistan, such causes should be investigated and prevented. Practical advice to increase the efficiency of treatment is included, considering the current situation in Uzbekistan. Data from South Korea, which has performed nationwide screening for two decades and has made progress in improving the prognosis of patients with gastrointestinal cancers, will be discussed as a literature control.

[What does the general and abdominal surgeon need to know about oncologically oriented radiotherapy?]

BACKGROUND

Radiotherapy is an integral component of most modern multimodal tumor treatment concepts, both in palliative and curative situations and intentions. This also applies to many tumor entities relevant in general as well as abdominal surgery. This can give rise to new challenges in the context of the daily clinical routine and interdisciplinary tumor conferences.

AIM

Practice relevant overview, based on selective references from the current scientific literature in medicine and own experiences obtained in daily work, for the oncological surgeon on radiotherapy-associated options for visceral tumor lesions. A particular focus is on rectal cancer, esophageal cancer, anal cancer and liver metastases.

METHOD

A narrative review is given.

RESULTS (SELECTED CORNER POINTS)

In total neoadjuvant therapy it is possible to avoid resection in rectal cancer if a good response is achieved and close monitoring can be provided. In esophageal cancer neoadjuvant chemoradiotherapy followed by resection can be considered the therapeutic regimen of choice for all suitable patients. If surgery is not an option, definitive chemoradiotherapy is an appropriate and favorable alternative, especially with respect to squamous cell carcinoma. Even taking the latest data on the topic into account, definitive chemoradiotherapy remains undisputedly recommended for anal cancer. Liver tumors can be locally ablated by stereotactic radiotherapy.

CONCLUSION

Close cooperation between disciplines in the context of tumor therapy remains essential for the best possible treatment and outcome of patients.