Management and Outcome of Local Regrowths in a Watch-and-wait Prospective Cohort for Complete Responses in Rectal Cancer

Endoscopic Predictors of Residual Tumor After Total Neoadjuvant Therapy: A Post Hoc Analysis From the Organ Preservation in Rectal Adenocarcinoma Trial

BACKGROUND

Restaging endoscopy plays a critical role in selecting patients with locally advanced rectal cancer who respond to neoadjuvant therapy for nonoperative management.

OBJECTIVE

This study evaluated the restaging endoscopic features that best predict the presence of residual tumor in the bowel wall.

DESIGN

This was a post hoc analysis of a prospective randomized trial.

SETTINGS

The Organ Preservation in Rectal Adenocarcinoma Trial randomly assigned patients across 18 institutions with stage II/III rectal adenocarcinoma to receive either induction or consolidation total neoadjuvant therapy. Surgeons completed a restaging tumor assessment form, which stratified patients across 3 tiers of clinical response.

PATIENTS

Patients enrolled in the Organ Preservation in Rectal Adenocarcinoma Trial with a completed tumor assessment form were included.

MAIN OUTCOME MEASURES

The main outcome was residual tumor, which was defined as either an incomplete clinical response or local tumor regrowth within 2 years of restaging. Independent predictors of residual tumor were identified using backward-selected multivariable logistic regression analysis. Subgroup analyses for complete and near complete clinical responders were performed.

RESULTS

Surgeons completed restaging forms for 263 patients at a median of 7.7 weeks after neoadjuvant therapy; 128 patients (48.7%) had a residual tumor. On multivariable regression analysis, several characteristics of a near complete response, including ulcer (OR 6.66; 95% CI, 2.54-19.9), irregular mucosa (OR 3.66; 95% CI, 1.61-8.68), and nodularity (OR 2.96; 95% CI, 1.36-6.58), remained independent predictors of residual tumor. A flat scar was associated with lower odds of harboring residual disease (OR 0.32; 95% CI, 0.11-0.93) for patients categorized as clinical complete responders.

LIMITATIONS

Limitations include analysis of endoscopic features at a single time point and ambiguities in tumor assessment form response criteria.

CONCLUSIONS

Patients with ulcer, nodularity, or irregular mucosa, on restaging endoscopy have higher odds of residual tumor. Recognizing negative prognostic implications of these features will help surgeons better select candidates for nonoperative management and suggests that patients with high-risk characteristics would benefit from close interval surveillance. See Video Abstract .

PREDICTORES ENDOSCPICOS DE TUMOR RESIDUAL DESPUS DE TERAPIA NEOADYUVANTE TOTAL UN ANLISIS POST HOC DEL ENSAYO DE PRESERVACIN DE RGANOS EN ADENOCARCINOMA RECTAL

ANTECEDENTES:La reestadificación por endoscopia juega un papel crítico en la selección de pacientes con cáncer de recto localmente avanzado que responden a la terapia neoadyuvante para el manejo no quirúrgico.OBJETIVO:Este estudio evaluó las características endoscópicas de reestadificación que mejor predicen la presencia de tumor residual en la pared intestinal.DISEÑO:Este fue un análisis post hoc de un ensayo prospectivo aleatorizado.ESCENARIO:El ensayo Organ Preservation in Rectal Adenocarcinoma aleatorizó a pacientes de 18 instituciones con adenocarcinoma de recto en estadio II/III para recibir terapia neoadyuvante total de inducción o consolidación. Los cirujanos completaron un formulario de reestadificación de evaluación del tumor, que estratificó a los pacientes en tres niveles de respuesta clínica.PACIENTES:Se incluyeron pacientes inscritos en el ensayo de preservación de órganos en adenocarcinoma rectal con un formulario de evaluación del tumor completado.PRINCIPALES MEDIDAS DE RESULTADO:El resultado principal fue presencia de tumor residual, que se definió como una respuesta clínica incompleta o un nuevo crecimiento local del tumor dentro de los dos años posteriores a la reestadificación. Los predictores independientes de tumor residual se identificaron mediante un análisis de regresión logística multivariable seleccionado hacia atrás. Se realizaron análisis de subgrupos para pacientes con respuesta clínica completa y casi completa.RESULTADOS:Los cirujanos completaron formularios de reestadificación para 263 pacientes en una mediana de 7.7 semanas después de la terapia neoadyuvante; 128 (48.7%) tenían tumor residual. En el análisis de regresión multivariable, varias características de una respuesta casi completa, incluyendo úlcera (OR 6.66; IC 95% 2.54-19.9), mucosa irregular (OR 3.66; IC 95% 1.61-8.68) y nodularidad (OR 2.96; IC 95% 1.36 -6.58) siguieron siendo predictores independientes de tumor residual. Una cicatriz plana se asoció con menores probabilidades de albergar enfermedad residual (OR 0.32; IC del 95 %: 0.11-0.93) para los pacientes clasificados como respondedores clínicos completos.LIMITACIONES:Las limitaciones de este estudio incluyen el análisis de las características endoscópicas en un solo momento y las ambigüedades en los criterios de respuesta.en la forma de evaluación del tumorCONCLUSIONES:Los pacientes con úlcera, nodularidad o mucosa irregular en la endoscopia de reestadificación tienen mayores probabilidades de tumor residual. El reconocer las implicaciones pronósticas negativas de estas características ayudará a los cirujanos a seleccionar mejor a los candidatos para el tratamiento no quirúrgico y sugiere que los pacientes con características de alto riesgo se beneficiarían de una vigilancia a intervalos estrechos. (Traducción-Dr. Jorge Silva Velazco ).

Rectal cancer - avoiding surgery?

Nonoperative treatment of rectal cancer is gaining popularity. Several trials recently demonstrated advantages in disease-free survival with total neoadjuvant treatment (TNT) with the addition of the watch and wait (WW) strategy for locally advanced rectal cancer. On longer follow-up, an unexpected increased risk in local recurrence in the TNT group at the RAPIDO trial suggested early surgery for nonresponding tumours. The WW option is globally accepted for a complete clinical response; however, a high rate of regrowth was found in a registry with an increased risk of distant metastases, questioning the deleterious effect of deferral of surgery in this group. The short- and long-term toxic effects of neoadjuvant treatment are costs to consider in the National Comprehensive Cancer Network guidelines compared with the European Society for Medical Oncology guidelines, which favour surgery alone if good mesorectal resection is assured with increasing surgical proficiency adjusted to the precise anatomical location.

Whether the watch-and-wait strategy has application value for rectal cancer with clinical complete response after neoadjuvant chemoradiotherapy? A network meta-analysis

The aim was to evaluate the efficacy and safety between the watch-and-wait strategy (WW), radical surgery (RS), and local excision (LE) for rectal cancer with clinical complete response (cCR) after neoadjuvant radiotherapy (nCRT). We searched MEDLINE, EMBASE, the Cochrane Library, and clinical trials to compare WW with RS and LE for patients with cCR until March 2023 and collected the following data: local recurrence (LR), distant metastasis (DM), cancer-related death (CRD), overall survival (OS), and disease-free survival (DFS). In total, 2240 patients from 21 studies were included. Pairwise meta-analysis revealed no statistically significant differences between the three groups in terms of CRD and 2-, 3-, and 5-year OS (P < 0.05). The RS group was significantly better than the WW group in terms of the LR rate (odds ratio [OR] = 0.12, 95 % confidence interval [CI]: 0.06-0.21, P < 0.001, I2 = 0 %], 3-year DFS (OR = 1.56, 95 % CI: 1.10-2.21, P = 0.01, I2 = 38 %), and 5-year DFS (OR = 2.30, 95 % CI: 1.53-3.46, P < 0.001, I2 = 34 %). The results of network meta-analysis were also similar. After sensitivity analysis, the 5-year OS of the RS group was significantly better than that of the WW group (OR = 2.77, 95 % CI: 1.28-6.00, P = 0.009, I2 = 33 %). Nevertheless, neither regression analysis nor subgroup analysis provided meaningful results. However, the cumulative meta-analysis of LR, DM, and 3- and 5-year DFS revealed significant turning points (P < 0.05). Our meta-analysis recommends using the WW strategy for patients with cCR having poor underlying conditions and high surgical risk; however, there is a risk of higher LR and worse survival after 3 years.

Organ Preservation and Survival by Clinical Response Grade in Patients With Rectal Cancer Treated With Total Neoadjuvant Therapy: A Secondary Analysis of the OPRA Randomized Clinical Trial

Importance

Assessing clinical tumor response following completion of total neoadjuvant therapy (TNT) in patients with locally advanced rectal cancer is paramount to select patients for watch-and-wait treatment.

Objective

To assess organ preservation (OP) and oncologic outcomes according to clinical tumor response grade.

Design, Setting, and Participants

This was secondary analysis of the Organ Preservation in Patients with Rectal Adenocarcinoma trial, a phase 2, nonblinded, multicenter, randomized clinical trial. Randomization occurred between April 2014 and March 2020. Eligible participants included patients with stage II or III rectal adenocarcinoma. Data analysis occurred from March 2022 to July 2023.

Intervention

Patients were randomized to induction chemotherapy followed by chemoradiation or chemoradiation followed by consolidation chemotherapy. Tumor response was assessed 8 (±4) weeks after TNT by digital rectal examination and endoscopy and categorized by clinical tumor response grade. A 3-tier grading schema that stratifies clinical tumor response into clinical complete response (CCR), near complete response (NCR), and incomplete clinical response (ICR) was devised to maximize patient eligibility for OP.

Main Outcomes and Measures

OP and survival rates by clinical tumor response grade were analyzed using the Kaplan-Meier method and log-rank test.

Results

There were 304 eligible patients, including 125 patients with a CCR (median [IQR] age, 60.6 [50.4-68.0] years; 76 male [60.8%]), 114 with an NCR (median [IQR] age, 57.6 [49.1-67.9] years; 80 male [70.2%]), and 65 with an ICR (median [IQR] age, 55.5 [47.7-64.2] years; 41 male [63.1%]) based on endoscopic imaging. Age, sex, tumor distance from the anal verge, pathological tumor classification, and clinical nodal classification were similar among the clinical tumor response grades. Median (IQR) follow-up for patients with OP was 4.09 (2.99-4.93) years. The 3-year probability of OP was 77% (95% CI, 70%-85%) for patients with a CCR and 40% (95% CI, 32%-51%) for patients with an NCR (P < .001). Clinical tumor response grade was associated with disease-free survival, local recurrence-free survival, distant metastasis-free survival, and overall survival.

Conclusions and Relevance

In this secondary analysis of a randomized clinical trial, most patients with a CCR after TNT achieved OP, with few developing tumor regrowth. Although the probability of tumor regrowth was higher for patients with an NCR compared with patients with a CCR, a significant proportion of patients achieved OP. These findings suggest the 3-tier grading schema can be used to estimate recurrence and survival outcomes in patients with locally advanced rectal cancer who receive TNT.

Trial Registration

ClinicalTrials.gov Identifier: NCT02008656.

Light and shadow of watch-and-wait strategy in rectal cancer: oncological result, clinical outcomes, and cost-effectiveness analysis

BACKGROUND

The watch-and-wait (WW) strategy is a potential option for patients with rectal cancer who obtain a complete clinic response after neoadjuvant therapy. The aim of this study is to analyze the long-term oncological outcomes and perform a cost-effectiveness analysis in patients undergoing this strategy for rectal cancer.

MATERIAL AND METHODS

The data of patients treated with the WW strategy were prospectively collected from January 2015 to January 2020. A control group was created, matched 1:1 from a pool of 480 patients undergoing total mesorectal excision. An independent company carried out the financial analysis. Clinical and oncological outcomes were analyzed in both groups. Outcome parameters included surgical and follow-up costs, quality-adjusted life years (QALYs), and the incremental cost per QALY gained or the incremental cost-effectiveness ratio (ICER).

RESULTS

Forty patients were included in the WW group, with 40 patients in the surgical group. During a median follow-up period of 36 months, metastasis-free survival (MFS) and overall survival (OS) were similar in the two groups. In the WW group, nine (22%) local regrowths were detected in the first 2 years. The permanent stoma rate was slightly higher after salvage surgery in the WW group compared to the surgical group (48.5% vs 20%, p < 0.01). The cost-effectiveness analysis was slightly better for the WW group, especially for low rectal cancer compared to medium-high rectal cancer (ICER =  - 108,642.1 vs ICER =  - 42,423).

CONCLUSIONS

The WW strategy in locally advanced rectal cancer offers similar oncological outcomes with respect to the surgical group and excellent results in quality of life and cost outcomes, especially for low rectal cancer. Nonetheless, the complex surgical field during salvage surgery can lead to a high permanent stoma rate; therefore, the careful selection of patients is mandatory.

The ultimate local failure rate after the watch-and-wait strategy for rectal cancer: a systematic review of literature and meta-analysis

BACKGROUND

We hypothesise that a high rate of tumour regrowth after the watch-and-wait (w&w) strategy may lead, despite salvage surgery, to a significant impairment of ultimate local control compared with immediate surgery.

MATERIALS AND METHODS

To test this hypothesis, we conducted meta-analyses of studies on the w&w strategy (both opportunistic and planned) with an ultimate local failure rate as an endpoint in three patient groups: (1) in all starting radio(chemo)therapy as potential w&w candidates, (2) in a subgroup starting w&w, and (3) in a subgroup with regrowth.

RESULTS

We identified eight studies for evaluation of local failure in group 1 (N = 837) and 36 studies in group 2 (N = 1914) and in group 3 (N = 439). The meta-analysis revealed an ultimate local failure rate of 8.0% (95% CI 4.8%-12.1%) in group 1 and 5.4% (95% CI 3.9%-7.1) in group 2. These rates are similar to those reported in the literature following preoperative chemoradiation and surgery. However, in the most unfavourable group 3 (with regrowth), the rate of ultimate local failure was 24.1% (95% CI 17.9%-30.9%), with the most common causes being patients' refusal of salvage total mesorectal excision (TME) (9.1%), recurrence after salvage TME (7.8%), distant metastases (4.1%), frailty (2.4%), and pelvic tumour unresectability (1.7%).

CONCLUSION

Nearly 25% of patients with regrowth (unfavourable subgroup) experienced ultimate local failure, primarily due to refusing salvage TME. The risk of ultimate local failure in patients initiating radio(chemo)therapy as potential w&w candidates, or in patients starting w&w, appears comparable to that reported after preoperative chemoradiation and surgery. However, this comparison may be biased, because w&w studies included more early tumours compared with surgical studies.

Top Colorectal Articles from 2021 to Inform Your Cancer Practice

Multimodality treatment for locally advanced rectal cancer is the standard of care. Treatments include surgery, radiation, and chemotherapy, with medical therapies now being favored in the neoadjuvant setting. Various regimens continue to be studied and defined in prospective randomized trials. The PRODIGE 23 and RAPIDO trials showed improved disease-free survival and pathologic complete response rates for split chemotherapy/radiation treatment and short-course radiation with consolidation chemotherapy, respectively; both compared with traditional neoadjuvant long course chemoradiation, surgery, and adjuvant chemotherapy. Furthermore, new regimens are yielding a higher rate of complete clinical response, allowing for non-operative management. Circulating tumor DNA provides a potential novel option for monitoring response to treatment and rectal cancer surveillance. This manuscript summarizes some of the key clinical trials and studies that are defining clinical practice.

CD11c+ and IRF8+ cell densities in rectal cancer biopsies predict outcomes of neoadjuvant chemoradiotherapy

Approximately 20% of locally advanced rectal cancer (LARC) patients treated preoperatively with chemoradiotherapy (CRT) achieve pathologically confirmed complete regression. However, there are no clinically implemented biomarkers measurable in biopsies that are predictive of tumor regression. Here, we conducted multiplexed immunophenotyping of rectal cancer diagnostic biopsies from 16 LARC patients treated preoperatively with CRT. We identified that patients with greater tumor regression had higher tumor infiltration of pan-T cells and IRF8+HLA-DR+ cells prior to CRT. High IRF8+HLA-DR+ cell density was further associated with prolonged disease-specific survival with 83% survival at 5 y compared to 28% in patients with low infiltration. Contrastingly, low CD11c+ myeloid cell infiltration prior to CRT was a putative biomarker associated with longer 3- and 5-y disease-free survival. The results demonstrate the potential use of rectal cancer diagnostic biopsies to measure IRF8+ HLA-DR+ cells as predictors of CRT-induced tumor regression and CD11c+ myeloid cells as predictors of LARC patient survival.

Total neoadjuvant therapy versus chemoradiotherapy for locally advanced rectal cancer: Bayesian network meta-analysis

BACKGROUND

Total neoadjuvant therapy is a promising treatment for locally advanced rectal cancer, utilizing either short-course radiotherapy or long-course chemoradiotherapy, but their relative efficacy remains unclear. The aim of this Bayesian network meta-analysis was to investigate clinical outcomes amongst patients receiving total neoadjuvant therapy with short-course radiotherapy or long-course chemoradiotherapy, and those receiving long-course chemoradiotherapy alone.

METHODS

A systematic literature search was performed. All studies that compared at least two of these three treatments for locally advanced rectal cancer were included. The primary endpoint was the pathological complete response rate, and survival outcomes were adopted as secondary outcomes.

RESULTS

Thirty cohorts were included. Compared with long-course chemoradiotherapy, both total neoadjuvant therapy with long-course chemoradiotherapy (OR 1.78, 95 per cent c.i. 1.43 to 2.26) and total neoadjuvant therapy with short-course radiotherapy (OR 1.75, 95 per cent c.i. 1.23 to 2.50) improved the pathological complete response rate. Similar benefits were observed in the sensitivity and subgroup analyses, except for short-course radiotherapy with one to two cycles of chemotherapy. No significant differences in survival outcomes were found amongst the three treatments. Long-course chemoradiotherapy with consolidation chemotherapy (HR 0.44, 95 per cent c.i. 0.20 to 0.99) exhibited higher disease-free survival than long-course chemoradiotherapy alone.

CONCLUSION

Compared with long-course chemoradiotherapy, both short-course radiotherapy with greater than or equal to three cycles of chemotherapy and total neoadjuvant therapy with long-course chemoradiotherapy can improve the pathological complete response rate, and long-course chemoradiotherapy with consolidation chemotherapy may lead to a marginal benefit in disease-free survival. The pathological complete response rate and survival outcomes are similar for total neoadjuvant therapy with short-course radiotherapy or long-course chemoradiotherapy.

Delayed TME Surgery in a Watch-and-Wait Strategy After Neoadjuvant Chemoradiotherapy for Rectal Cancer: An Analysis of Hospital Costs and Surgical and Oncological Outcomes

BACKGROUND

A watch-and-wait strategy for patients with rectal cancer with a clinical complete response after neoadjuvant chemoradiotherapy is a valuable alternative for rectal resection. However, there are patients who will have residual tumor or regrowth during watch and wait.

OBJECTIVE

The aim of this study was to investigate safety and costs for patients who underwent delayed surgery after neoadjuvant chemoradiotherapy.

DESIGN

This is a retrospective cohort study with prospectively collected data.

SETTINGS

The study was conducted at a large teaching hospital.

PATIENTS

Between January 2015 and May 2020, 622 new rectal cancer patients were seen, of whom 200 received neoadjuvant chemoradiotherapy. Ninety-four patients were included, 65 of whom underwent immediate surgery and 29 of whom required delayed surgery after an initial watch-and-wait approach.

MAIN OUTCOME MEASURES

Outcome measures included 30-day postoperative morbidity rate, hospital costs. 2-year overall and disease-free survival.

RESULTS

There was no difference in length of stay (9 vs 8; p = 0.83), readmissions (27.6% vs 10.0%; p = 0.10), surgical re-interventions (15.0% vs 3.4%; p = 0.16), or stoma-free rate (52.6% vs 31.0%; p = 0.09) between immediate and delayed surgery groups. Hospital costs were similar in the delayed group (€11,913 vs €13,769; p = 0.89). Two-year overall survival (93% vs 100%; p = 0.23) and disease-free survival (78% vs 81%; p = 0.47) rates were comparable.

LIMITATIONS

Limitations included small sample size, follow-up time and retrospective design.

CONCLUSION

Delayed surgery for regrowth in a watch-and-wait program or for persistent residual disease after a repeated assessment is not associated with an increased risk of postoperative morbidity or a significant rise in costs compared to immediate total mesorectal excision. There also appears to be no evident compromise in oncological outcome. Repeated response assessment in patients with a near complete clinical response after neoadjuvant chemoradiotherapy is a useful approach to identify more patients who can benefit from a watch-and-wait strategy. See Video Abstract at http://links.lww.com/DCR/B836 .

CIRUGA DE TME RETRASADA EN UNA ESTRATEGIA DE WATCH AND WAIT DESPUS DE LA QUIMIORRADIOTERAPIA NEOADYUVANTE PARA CNCER DE RECTO UN ANLISIS DE COSTOS HOSPITALARIOS, Y DE RESULTADOS QUIRRGICOS Y ONCOLGICOS

ANTECEDENTES: Una estrategia de Watch and Wait para pacientes con cáncer de recto con una respuesta clínica completa después de quimiorradioterapia neoadyuvante es una alternativa valiosa en vez de resección rectal. Sin embargo, hay pacientes que tendrán tumor residual o un recrecimiento durante el Watch and Wait .OBJETIVO: El objetivo fue investigar la seguridad y los costos para los pacientes que se sometieron a una cirugía diferida después de la quimiorradioterapia neoadyuvante.DISEÑO: Este es un estudio de cohorte retrospectivo con datos recolectados prospectivamente.AJUSTE: El estudio se llevó a cabo en un gran hospital universitario.PACIENTES: Entre enero de 2015 y mayo de 2020, se atendieron 622 nuevos pacientes con cáncer de recto, de los cuales 200 recibieron quimiorradioterapia neoadyuvante. Se incluyeron 94 pacientes, de los cuales 65 se sometieron a cirugía inmediata y 29 pacientes requirieron cirugía diferida después de un enfoque inicial de observación y espera.PRINCIPALES MEDIDAS DE RESULTADO: se incluyeron la tasa de morbilidad posoperatoria a 30 días, los costos hospitalarios y las sobrevidas general y libre de enfermedad a dos años.RESULTADOS: No hubo diferencia en la duración de la estancia (9 vs 8, p = 0,83), reingresos (27,6% vs 10,0%, p = 0,10), reintervenciones quirúrgicas (15,0% vs 3,4%, p = 0,16) y tasa libre de estoma (52,6% vs 31,0%, p = 0,09) entre los grupos de cirugía inmediata y tardía. Los costos hospitalarios fueron similares en el grupo retrasado (11913 € frente a 13769 €, p = 0,89). Las tasas de sobrevida general a dos años (93% frente a 100%, p = 0,23) y sobrevida libre de enfermedad (78% frente a 81%, p = 0,47) fueron comparables.LIMITACIONES: Tamaño de muestra pequeño, tiempo de seguimiento y diseño retrospectivo.CONCLUSIÓN: La cirugía tardía para el recrecimiento en un programa de Watch and Wait o para la enfermedad residual persistente después de una evaluación repetida no se asocia con un riesgo mayor de morbilidad posoperatoria ni con un aumento significativo en los costos, en comparación con la escisión total de mesorrecto inmediata. Tampoco parece haber un compromiso evidente en el resultado oncológico. La evaluación repetida de la respuesta en pacientes con una respuesta clínica casi completa después de la quimiorradioterapia neoadyuvante es un enfoque útil para identificar más pacientes que pueden beneficiarse de una estrategia de Watch and Wait . Consulte Video Resumen en http://links.lww.com/DCR/B836 . (Traducción-Dr. Juan Carlos Reyes ).

Watch-and-Wait is an Option in Rectal Cancer Patients: From Controversy to Common Clinical Practice

Overview of the introduction of organ preservation in rectal cancer patients and future challenges.

Chemoradiation and consolidation chemotherapy for rectal cancer provides a high rate of organ preservation with a very good long-term oncological outcome: a single-center cohort series

Aim

To report long-term oncological outcomes and organ preservation rate with a chemoradiotherapy-consolidation chemotherapy (CRT-CNCT) treatment for locally advanced rectal cancer (LARC).

Method

Retrospective analysis of prospectively maintained database was performed. Oncological outcomes of mid-low LARC patients (n=60) were analyzed after a follow-up of 63 (50–83) months. Patients with clinical complete response (cCR) were treated with the watch-and-wait (WW) protocol. Patients who could not achieve cCR were treated with total mesorectal excision (TME) or local excision (LE).

Results

Thirty-nine (65%) patients who achieved cCR were treated with the WW protocol. TME was performed in 15 (25%) patients and LE was performed in 6 (10%) patients. During the follow-up period, 10 (25.6%) patients in the WW group had regrowth (RG) and 3 (7.7%) had distant metastasis (DM). Five-year overall survival (OS) and disease-free survival (DFS) were 90.1% and 71.6%, respectively, in the WW group. Five-year OS and DFS were 94.9% (95% CI: 88–100%) and 80% (95% CI: 55.2–100%), respectively, in the RG group. For all patients (n=60), 5-year TME-free DFS was 57.3% (95% CI: 44.3–70.2%) and organ preservation-adapted DFS was 77.5% (95% CI: 66.4–88.4%). For the WW group (n=39), 5-year TME-free DFS was 77.5% (95% CI: 63.2–91.8%) and organ preservation-adapted DFS was 85.0% (95% CI: 72.3–97.8%).

Conclusion

CRT-CNCT provides cCR as high as 2/3 of LARC patients. Regrowths, developed during follow-up, can be successfully salvaged without causing oncological disadvantage if strict surveillance is performed.

Role of Local Excision for Suspected Regrowth in a Watch and Wait Strategy for Rectal Cancer

Rectal cancer patients with a clinical complete response to neoadjuvant (chemo)radiation are eligible for Watch and Wait (W&W). For local regrowth, total mesorectal excision (TME) is considered the standard of care. This study evaluated local excision (LE) for suspected local regrowth. From 591 patients prospectively entered into a national W&W registry, 77 patients with LE for regrowth were included. Outcomes analyzed included histopathologic findings, locoregional recurrence, long-term organ preservation, and colostomy-free and overall survival. In total, 27/77 patients underwent early LE (<6 months after neoadjuvant radiotherapy) and 50/77 underwent late LE (≥6 months). Median follow-up was 53 (39−69) months. In 28/77 patients the LE specimen was histopathologically classified as ypT0 (including 9 adenomas); 11/77 were ypT1, and 38/77 were ypT2−3. After LE, 13/77 patients with ypT2−3 and/or irradical resection underwent completion TME. Subsequently, 14/64 patients without completion TME developed locoregional recurrence, and were successfully treated with salvage TME. Another 8/77 patients developed distant metastases. At 5 years, overall organ preservation was 63%, colostomy-free survival was 68%, and overall survival was 96%. There were no differences in outcomes between early or late LE. In W&W for rectal cancer, LE can be considered as an alternative to TME for suspected regrowth in selected patients who wish to preserve their rectum or avoid colostomy in distal rectal cancer.

Predicting pathologic complete response in locally advanced rectal cancer patients after neoadjuvant therapy: a machine learning model using XGBoost

PURPOSE

Watch and wait strategy is a safe and effective alternative to surgery in patients with locally advanced rectal cancer (LARC) who have achieved pathological complete response (pCR) after neoadjuvant therapy (NAT); present restaging methods do not meet clinical needs. This study aimed to construct a machine learning (ML) model to predict pCR preoperatively.

METHODS

LARC patients who received NAT were included to generate an extreme gradient boosting-based ML model to predict pCR. The group was divided into a training set and a tuning set at a 7:3 ratio. The SHapley Additive exPlanations value was used to quantify feature importance. The ML model was compared with a nomogram model developed using independent risk factors identified by conventional multivariate logistic regression analysis.

RESULTS

Compared with the nomogram model, our ML model improved the area under the receiver operating characteristics from 0.72 to 0.95, sensitivity from 43 to 82.2%, and specificity from 87.1 to 91.6% in the training set, the same trend applied to the tuning set. Neoadjuvant radiotherapy, preoperative carbohydrate antigen 125 (CA125), CA199, carcinoembryonic antigen level, and depth of tumor invasion were significant in predicting pCR in both models.

CONCLUSION

Our ML model is a potential alternative to the existing assessment tools to conduct triage treatment for patients and provides reference for clinicians in tailoring individual treatment: the watch and wait strategy is used to avoid surgical trauma in pCR patients, and non-pCR patients receive surgical treatment to avoid missing the optimal operation time window.

A meta-analysis of the watch-and-wait strategy versus total mesorectal excision for rectal cancer exhibiting complete clinical response after neoadjuvant chemoradiotherapy

Background

Some clinical researchers have reported that patients with cCR (clinical complete response) status after neoadjuvant chemoradiotherapy (nCRT) could adopt the watch-and-wait (W&W) strategy. Compared with total mesorectal excision (TME) surgery, the W&W strategy could achieve a similar overall survival. Could the W&W strategy replace TME surgery as the main treatment option for the cCR patients? By using the meta-analysis method, we evaluated the safety and efficacy of the W&W strategy and TME surgery for rectal cancer exhibiting cCR after nCRT.

Methods

We evaluated two treatment strategies for rectal cancer with cCR after nCRT up to July 2021 by searching the Cochrane Library, PubMed, Wanfang, and China National Knowledge Infrastructure (CNKI) databases. Clinical data for primary outcomes (local recurrence, cancer-related death and distant metastasis), and secondary outcomes (disease-free survival (DFS) and overall survival (OS)) were collected to evaluate the efficacy and safety in the two groups.

Results

We included nine studies with 818 patients in the meta-analysis, and there were five moderate-quality studies and four high-quality studies. A total of 339 patients were in the W&W group and 479 patients were in the TME group. The local recurrence rate in the W&W group was greater than that in the TME group in the fixed-effects model (OR 8.54, 95% CI 3.52 to 20.71, P < 0.001). The results of other outcomes were similar in the two groups.

Conclusion

The local recurrence rate of the W&W group was greater than that in the TME group, but other results were similar in the two groups. With the help of physical examination and salvage therapy, the W&W strategy could achieve similar treatment effects with the TME approach.

Trial registration

Protocol registration number: CRD42021244032.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02415-y.

The growing trend for no primary surgery in colorectal cancer

AIM

In colorectal cancer (CRC), surgery of the primary site is commonly curative. Our aim was to determine estimates of 'no surgery' for primary CRC while identifying common reasons for no surgery.

METHOD

We identified all patients with a diagnosis of colorectal adenocarcinoma from the National Cancer Database between January 2004 and December 2016. Then, we identified patients who did not undergo surgery on the primary tumour and their demographic, tumour and institutional characteristics. Kaplan-Meier and logistic regression analyses were used to evaluate specific factors associated with overall survival as related to no surgery and recommendations against operative management.

RESULTS

A total of 1,208,878 patients with CRC were identified, 14.5% of whom had no surgery of the primary cancer. No surgery was more common in rectal cancer than in colon cancer. Despite a steady incidence of CRC diagnoses, the likelihood of no surgery grew by 170% over the study period. Metastatic disease was noted in 53.7% of the no surgery cohort. Nine per cent of the no surgery patient cohort received a recommendation against surgery despite the absence of metastatic disease, 7.5% refused surgery and only 2% underwent palliative surgery. On multivariable analysis, patients who were not recommended to have surgery were more likely to be older, uninsured, comorbid and receive care at a single hospital. The no surgery patients had significantly lower overall survival.

CONCLUSION

A substantial proportion of patients with CRC do not have surgery. Interventions aimed at expanding access and promoting second opinions at other cancer hospitals might reduce the growing rate of no surgery in CRC.

Beneficiaries of radical surgery among clinical complete responders to neoadjuvant chemoradiotherapy in rectal cancer

This study aimed to identify patients who benefit from radical surgery among those with rectal cancer who achieved clinical complete response (cCR). Patients with locally advanced rectal cancer (LARC; stage II/III) who achieved cCR after neoadjuvant chemoradiotherapy (nCRT) were included (n = 212). Univariate/multivariate Cox analysis was performed to validate predictors for distant metastasis‐free survival (DMFS). A decision tree was generated using recursive partitioning analysis (RPA) to categorize patients into different risk stratifications. Total mesorectal excision (TME) was compared with the watch‐and‐wait (W&W) strategy in each risk group. Two molecular predicators of CEA and CA19‐9 were selected to establish the RPA‐based risk stratification, categorizing LARC patients into low‐risk (n = 139; CA19‐9 < 35 U/mL and CEA < 5 ng/mL) and high‐risk (n = 73; CA19‐9 ≥ 35 U/mL or CEA ≥5 ng/mL) groups. Superior 5‐y DMFS was observed in the low‐risk group vs. the high‐risk group (92.9% vs. 76.2%, P = .002). Low‐risk LARC patients who underwent TME had significantly improved 5‐y DMFS compared with their counterparts receiving the W&W strategy (95.9% vs. 84.3%; P = .028). No significant survival difference was observed in high‐risk patients receiving the 2 treatment modalities (77.9% vs. 94.1%; P = .143). LARC patients with cCR who had both baseline CA19‐9 < 35 U/mL and CEA < 5 ng/mL may benefit from radical surgery.

Advantageous factors of R0 curative conversion esophagectomy and the optimal extent of lymphadenectomy after induction therapy for cT4b thoracic esophageal cancer

AIM

This study aimed to clarify the prognostic factors, the advantageous factors of R0 curative resection, and optimal extents of lymph node dissection for conversion esophagectomy after induction therapy.

METHODS

Among 1903 patients with esophageal cancer at Toranomon Hospital between January 2006 to May 2020, 151 patients with locally advanced T4b thoracic esophageal cancer were divided into two groups according to treatment: conversion surgery group (n = 54) and non-surgical treatment group (n = 97) for comparison.

RESULTS

The patients who underwent R0 curative resection showed preferable survival comparable to the survival rate of patients with cCR in the non-surgical treatment group (1-, 3- and 5-year survival: 96.9%, 82.1% and 76.7% vs 94.1%, 86.3%, and 86.3%; P = 0.770). Multivariate analysis revealed that the T4b tumor invasion by primary site (odds ratio (OR) = 6.100; 95% CI, 1.439-25.865: P = 0.014) and time to conversion surgery from start of induction therapy within four months (OR = 5.229; 95% CI, 1.296-21.102: P = 0.020) were all independent advantageous factors of R0 curative resection. Actuarial 1-, 3- and 5-year survival rates in patients who underwent conversion surgery with D2-3 lymphadenectomy were 90.9%, 48.6%, and 40.8%, respectively.

CONCLUSIONS

R0 resection led to improved prognosis in conversion esophagectomy for cT4b esophageal cancer. The T4b tumor invasion by primary site and time to conversion surgery from start of induction therapy within 4 months were independent advantageous factors of R0 curative resection. In addition, standard radical esophagectomy including prophylactic D2-/3- lymphadenectomy should be performed if it is possible, while taking adequate care regarding the increased risk after induction therapy.

The challenges in colorectal cancer management during COVID-19 epidemic

It has been over 2 months since the start of the Coronavirus disease 2019 (COVID-19) outbreak. The epidemic stage of COVID-19 has brought great challenges to the diagnosis and management of colorectal cancer (CRC) patients. Symptoms, such as fever and cough caused by cancer, and the therapeutic process (including chemotherapy and surgery) should be differentiated from some COVID-19 related characteristics. Besides, clinical workers should not only consider the therapeutic strategy for cancer, but also emphasize COVID-19's prevention. Moreover, the detailed therapeutic regimens of CRC patients may be different from the usual. Also, treatment principles may various for CRC patients with or without severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, as well as patients with or without an emergency presentation. In this paper, we want to discuss the above-mentioned problems based on previous guidelines, the current working status and our experiences, to provide a reference for medical personnel.