Pathologic Assessment of Rectal Carcinoma after Neoadjuvant Radio(chemo)therapy: Prognostic Implications

Could meeting the standards of the National Accreditation Program for Rectal Cancer in the National Cancer Database improve patient outcomes?

AIM

The National Accreditation Program for Rectal Cancer (NAPRC) was developed to improve rectal cancer patient outcomes in the United States. The NAPRC consists of a set of process and outcome measures that hospitals must meet in order to be accredited. We aimed to assess the potential of the NAPRC by determining whether achievement of the process measures correlates with improved survival.

METHODS

The National Cancer Database was used to identify patients undergoing curative proctectomy for non-metastatic rectal cancer from 2010 to 2014. NAPRC process measures identified in the National Cancer Database included clinical staging completion, treatment starting <60 days from diagnosis, carcinoembryonic antigen level measured prior to treatment, tumour regression grading and margin assessment.

RESULTS

There were 48 669 patients identified with a mean age of 62 ± 12.9 years and 61.3% of patients were men. The process measure completed most often was assessment of proximal and distal margins (98.4%) and the measure completed least often was the serum carcinoembryonic antigen level prior to treatment (63.8%). All six process measures were completed in 23.6% of patients. After controlling for age, gender, comorbidities, annual facility resection volume, race and pathological stage, completion of all process measures was associated with a statistically significant mortality decrease (Cox hazard ratio 0.88, 95% CI 0.81-0.94, P < 0.001).

CONCLUSION

Participating institutions provided complete datasets for all six process measures in less than a quarter of patients. Compliance with all process measures was associated with a significant mortality reduction. Improved adoption of NAPRC process measures could therefore result in improved survival rates for rectal cancer in the United States.

The Glasgow Microenvironment Score and risk and site of recurrence in TNM I-III colorectal cancer

BACKGROUND

Glasgow Microenvironment Score (GMS) stratifies long-term survival into three groups based on tumour phenotype: peritumoural inflammation (Klintrup-Mäkinen (KM)) and tumour stroma percentage (TSP). However, it is not known if the location of disease recurrence is influenced by the GMS category.

METHODS

Seven hundred and eighty-three TNM I-III colorectal cancers (CRC) were included. GMS (GMS0-high KM; GMS1-low KM, low TSP; GMS2-low KM, high TSP) and cancer-specific survival (CSS), overall survival (OS) and disease recurrence were assessed using Cox regression analysis.

RESULTS

Of the 783 patients, 221 developed CRC recurrence; 65 developed local recurrence + systemic disease. GMS was independent for CSS (HR 1.50, 95% CI 1.17-1.92, p < 0.001) and OS (HR 1.23, 1.05-1.44, p = 0.01). Higher GMS category was associated with T-stage, N-stage, emergency presentation and venous invasion. GMS was independent for local+systemic recurrence (HR 11.53, 95% CI 1.45-91.85, p = 0.04) and distant-only recurrence (HR 3.01, 95% CI 1.59-5.71, p = 0.002). GMS 2 disease did not appear to have statistically better outcomes with adjuvant chemotherapy in high-risk disease.

CONCLUSION

Although confounded by a higher rate of T4 and node-positive disease, GMS 1 and 2 are associated with an increased risk of local and distant recurrence. GMS is an independent poor prognostic indicator for recurrent colorectal cancer. Higher GMS patients may benefit from enhanced postoperative surveillance.

Patient Survival With ypT0N+ Following Neoadjuvant Therapy in Rectal Cancer

BACKGROUND

After neoadjuvant therapy, pathologic analysis of rectal cancer resected specimens may show a complete response in the primary tissue cancer with residual tumor in the lymph nodes (ypT0N+).

OBJECTIVES

The aim of this study was to describe the 5-year overall survival and factors associated with survival of ypT0N+ patients with rectal cancer who had neoadjuvant therapy followed by surgery and to compare these patients' survival with patients in other pathologic categories.

DESIGN

We conducted a retrospective analysis.

SETTINGS

We used the National Cancer Database.

PATIENTS

We identified patients with rectal adenocarcinoma who underwent total neoadjuvant therapy or neoadjuvant chemoradiation followed by surgery between 2006 and 2016. Besides ypT0N+, 5 pathologic categories were identified: ypT0N0, ypT1-2N0, ypT3-4N0, ypT1-2N+, and ypT3-4N+.

MAIN OUTCOME MEASURE

The primary outcome measure was 5-year overall survival.

RESULTS

We included 30,751 patients with rectal adenocarcinoma. A total of 342 patients developed ypT0N+, of whom 181 (52.9%) received total neoadjuvant therapy. Among patients who received total neoadjuvant therapy, developing ypT0N+ was associated with a lower 5-year overall survival than ypT0N0 and ypT1-2N0. However, ypT0N+ disease was associated with a higher 5-year overall survival than ypT3-4N+. There were no differences in 5-year overall survival between ypT0N+ and ypT3-4N0 or ypT1-2N+. Similar findings were noticed among patients who received neoadjuvant chemoradiation and adjuvant chemotherapy. For patients with ypT0N+, older age, male gender, and higher number of positive lymph nodes were all associated with a decrease in the overall survival.

LIMITATIONS

Limitations include the retrospective nature of this study, lack of variables describing the chemotherapy and radiation regimens used, and paucity of data on disease-specific survival or recurrence.

CONCLUSIONS

Developing ypT0N+ was associated with a lower 5-year overall survival than ypT0N0 and ypT1-2N0. However, it was associated with a higher 5-year overall survival than ypT3-4N+. See Video Abstract at http://links.lww.com/DCR/B863 .

SOBREVIDA DE LOS PACIENTES CON YPTN DESPUS DE LA TERAPIA NEOADYUVANTE EN EL CNCER DE RECTO

ANTECEDENTES:Después del tratamiento neoadyuvante en el cáncer de recto bajo, el análisis patológico de la pieza operatoria resecada, puede mostrar una respuesta patológica completa del tumor primario pero con tumor residual en los ganglios linfáticos (ypT0N+).OBJETIVOS:Describir la sobrevida general a 5 años y los factores asociados con la sobrevida de los pacientes ypT0N+ con cáncer de recto, que recibieron terapia neoadyuvante seguida de cirugía y comparar la sobrevida de estos pacientes con la de pacientes con otros estadios patológicos.DISEÑO:Realizamos un análisis retrospectivo.AJUSTES:Utilizamos la base de datos nacional del cáncer.PACIENTES:Identificamos pacientes con adenocarcinoma de recto que se sometieron a terapia neoadyuvante total, seguida de cirugía entre 2006 y 2016. Además de ypT0N +, se identificaron 5 categorías patológicas: ypT0N0, ypT1-2N0, ypT3-4N0, ypT1-2N+, e ypT3-4N+.PRINCIPAL MEDIDA DE RESULTADO:La medida de resultado principal fue la supervivencia general a 5 años.RESULTADOS:Se incluyeron 30.751 pacientes con adenocarcinoma de recto. Un total de 342 pacientes desarrollaron ypT0N+, de los cuales 181 (52,9%) recibieron terapia neoadyuvante total. Entre los pacientes que recibieron terapia neoadyuvante total, el desarrollo de ypT0N+ se asoció con una supervivencia general a 5 años más baja que ypT0N0 e ypT1-2N0. Sin embargo, la enfermedad ypT0N+ se asoció con una supervivencia general a 5 años más alta que ypT3-4N+. No hubo diferencias en la supervivencia global a 5 años entre ypT0N+ y ypT3-4N0 o ypT1-2N+. Se observaron hallazgos similares entre los pacientes que recibieron terapia neoadyuvante y quimioterapia adyuvante. Para los pacientes con ypT0N+, la edad avanzada, el sexo masculino y un mayor número de ganglios linfáticos positivos se asociaron con una disminución en la supervivencia general.LIMITACIONES:Las limitaciones incluyen la naturaleza retrospectiva del estudio, la falta de variables que describan los regímenes de quimioterapia y radiación utilizados y la escasez de datos sobre la supervivencia o la recurrencia específicas de la enfermedad.CONCLUSIONES:El desarrollo de ypT0N+ se asoció con una supervivencia general a 5 años más baja que ypT0N0 e ypT1-2N0. Sin embargo, se asoció con una supervivencia global a 5 años más alta que ypT3-4N+. Consulte Video Resumen en http://links.lww.com/DCR/B863 . (Traducción-Dr. Rodrigo Azolas ).

OUP accepted manuscript

Purpose

Methods

Results

Conclusion

Predicting Treatment Response of Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer Using Amide Proton Transfer MRI Combined With Diffusion-Weighted Imaging

Objective

To evaluate amide proton weighted (APTw) MRI combined with diffusion-weighted imaging (DWI) in predicting neoadjuvant chemoradiotherapy (NCRT) response in patients with locally advanced rectal cancer (LARC).

Methods

53 patients with LARC were enrolled in this retrospective study. MR examination including APTw MRI and DWI was performed before and after NCRT. APTw SI, ADC value, tumor size, CEA level before and after NCRT were assessed. The difference of the above parameters between before and after NCRT was calculated. The tumor regression grading (TRG) was assessed by American Joint Committee on Cancer’s Cancer Staging Manual AJCC 8th score. The Shapiro-Wilk test, paired t-test and Wilcoxon Signed Ranks test, two-sample t-test, Mann-Whitney U test and multivariate analysis were used for statistical analysis.

Results

Of the 53 patients, 19 had good responses (TRG 0-1), 34 had poor responses (TRG 2-3). After NCRT, all the rectal tumors demonstrated decreased APT values, increased ADC values, reduced tumor volumes and CEA levels (all p < 0.001). Good responders demonstrated higher pre-APT values, higher Δ APT values, lower pre- ADC values and higher Δ tumor volumes than poor responders. Pre-APT combined with pre-ADC achieved the best diagnostic performance, with AUC of 0.895 (sensitivity of 85.29%, specificity of 89.47%, p < 0.001) in predicting good response to NCRT.

Conclusion

The combination of APTw and DWI may serve as a noninvasive biomarker for evaluating and identifying response to NCRT in LARC patients.

Pathological Predictors of Response to Neoadjuvant Treatment in Rectal Carcinoma

PURPOSE

Neoadjuvant chemoradiotherapy has now become a standard treatment for rectal cancer. Recently, attempts have been made to predict the response rate to this treatment to decide whether or not it must be performed. However, tissue factors for predicting the response rate is not cohesively reviewed.

METHODS

Eighty-three patients with rectal cancer, all under neoadjuvant chemoradiotherapy and subsequent surgery, were examined for tissue factors in the biopsy sample. The tissue factors examined include tumor differentiation grade, lymphovascular invasion, perineural invasion, pathological stage, and lymphocytic infiltration. Lymphocytic infiltration was investigated by immunohistochemistry for CD8 T lymphocyte in biopsy samples.

RESULTS

In this study, tissue factors were found to play a decisive role in predicting response to neoadjuvant treatment. The most important factor was the pathological stage, which has the highest correlation with response to treatment. There is a significant relationship between CD8 lymphocyte infiltration and response to treatment (P value = 0.018). Primary perineural invasion and lymphovascular invasion also have a significant meaningful relationship with response to treatment (P value = 0.021 and P value = 0.036).

CONCLUSION

In this study, it was determined that the investigated factors have a significant relationship with response to treatment and could be used to predict the response to treatment, and if a low possibility of positive response exists, prevention of the complications of neoadjuvant chemoradiotherapy for the patients could occur.

Mucin Pools Following Neoadjuvant Chemoradiotherapy for Rectal Cancer: A Marker of Response or Epiphenomenon?

Neoadjuvant chemoradiotherapy (CRT) is the standard of care for locally advanced rectal cancer. Morphologic changes such as fibrosis, inflammatory infiltrates, and the formation of extracellular mucin pools can be identified in the resection specimen after neoadjuvant CRT. The association of mucin pool formation with clinicopathologic variables and outcomes is unclear. The aim of this study was to meta-analyze all available evidence with regard to mucin pool formation and clinicopathologic outcomes following neoadjuvant CRT for rectal cancer. A comprehensive search for published studies analyzing outcomes between patients who formed mucin pools and patients who did not following neoadjuvant CRT for rectal cancer was performed. A random-effects model was used to combine the data. This study adhered to the recommendations of the MOOSE (Meta-analyses of Observational Studies in Epidemiology) guidelines. Data from 11 studies describing 1947 patients were included. Mucin pool formation was not associated with sex, T stage, N stage, tumor regression, pathologic complete response rate, lymphovascular invasion, perineural invasion, differentiation, margin status, local or distant recurrence, and disease-free or overall survival. Mucin pool formation is not associated with tumor response or downstaging; furthermore, on the basis of these data, it is not associated with local or systemic recurrence rate or survival.

Neoadjuvant chemoradiation and rectal cancer

Neoadjuvant chemoradiation (NACR) is now standard of care in stage II and III rectal cancer. The advent of this modality of treatment has impacted on the way the pathological evaluation of resection specimens that have been subjected to preoperative chemoradiation is conducted. The gross description, sectioning and microscopic examination have had to be adapted to accommodate the changes induced by NACR. Attempts at introducing a uniform approach to the gross triaging and reporting of these specimens have been met with muted response. There still exists much variation in approach. The purpose of this overview is to highlight some of the newer developments and issues around NACR-treated rectal cancers from a pathological point of view. The NACR-treated resection specimens should be handled in a consistent manner, at least within individual institutions, if not universally. There should be generous sampling with multiple sections taken as tumour is often sequestered deep in the bowel wall. Microscopic examination should be extra vigilant as residual cancer can be present as single cells or small clusters, often deep in the muscularis propria or serosa. Acellular pools of mucin or non-viable tumour cells in mucin within the bowel wall or lymph nodes are not regarded as positive and do not upstage the tumour. The issue of grading of regression has been the subject of much debate, and several approaches have been published. It is recommended that a system that has clinical meaning and use to oncologists be used. Lymph node counts will be reduced after NACR, but reasonable attempts to accrue 12 nodes should be made.

Placement of a self-expandable metallic stent as a bridge to surgery for large bowel obstruction induced by effective neoadjuvant therapy: report of three cases

Background

Self-expandable metallic stent placement is a widely performed palliative procedure or bridge to surgery for obstructive colorectal cancer. However, the feasibility of this procedure for large bowel obstruction induced by effective neoadjuvant therapy is unclear.

Case presentation

We herein report three such cases involving a 61-year-old man who underwent neoadjuvant chemoradiotherapy for lower rectal cancer, a 56-year-old woman who underwent neoadjuvant chemotherapy for lower rectal cancer, and a 63-year-old woman who underwent neoadjuvant chemotherapy for lower rectal cancer. All were emergently hospitalized with large bowel obstruction that developed while undergoing neoadjuvant therapy. Colonoscopy revealed smooth strictures caused by effective neoadjuvant therapy. Self-expandable metallic stents were placed across the obstruction as a bridge to surgery, and laparoscopic low anterior resection was uneventfully performed in all patients.

Conclusions

We successfully treated three patients with large bowel obstruction induced by a good response to neoadjuvant therapy using self-expandable metallic stents as a bridge to surgery. Further studies with larger sample sizes are warranted to assess the feasibility of this strategy.

Is There a Role for Programmed Death Ligand-1 Testing and Immunotherapy in Colorectal Cancer With Microsatellite Instability? Part I-Colorectal Cancer: Microsatellite Instability, Testing, and Clinical Implications

CONTEXT

- Colorectal cancer (CRC) represents the third most-common cancer in developed countries and is a leading cause of cancer deaths worldwide. Two recognized pathways contribute to CRC development: a more-common chromosomal instability pathway and, in 15% of cases, a deficient mismatch repair or microsatellite instability-high (MSI-H) pathway. The MSI-H CRC can be associated with somatic or germline mutations. Microsatellite status has been recognized as a prognostic and predictive biomarker.

OBJECTIVES

- To summarize the molecular pathways of CRC, with an emphasis on the MSI (mismatch repair) pathway; the recommended MSI testing algorithms and interpretation; and the prognostic and predictive role of MSI-H status in personalized treatment, including adjuvant chemotherapy, targeted therapy, and immune checkpoint inhibitor therapy.

DATA SOURCES

- A PubMed (US National Library of Medicine, Bethesda, Maryland) review was performed for articles pertaining to CRC, MSI and mismatch repair systems, molecular classification, immune response, programmed death receptor-1/programmed death ligand-1, and immunotherapy.

CONCLUSIONS

- Although the TNM classification of malignant tumor stage remains the key determinant of CRC prognosis and treatment, there are considerable stage-independent, interindividual differences in clinical outcome and therapy response by patients. In addition, MSI-H status has an important role in CRC management and can be reliably detected by molecular and immunohistochemistry techniques and genetic testing. Efforts must be made to identify whether MSI-H CRC is germline or sporadic to ensure appropriate treatment, accurate prognosis, and risk assessment for relatives. Microsatellite status has been recognized as a good prognostic indicator and is predictive of a poor response to 5-fluorouracil-based chemotherapy and a good response to programmed death ligand-1 inhibitor pembrolizumab in metastatic/refractory MSI-H CRC.

Population-based study of survival for women with serous cancer of the ovary, fallopian tube, peritoneum or undesignated origin - on behalf of the Swedish gynecological cancer group (SweGCG)

OBJECTIVE

The aim of the study was to determine survival outcome in patients with serous cancer in the ovary, fallopian tube, peritoneum and of undesignated origin.

METHODS

Nation-wide population-based study of women≥18years with histologically verified non-uterine serous cancer, included in the Swedish Quality Registry for primary cancer of the ovary, fallopian tube and peritoneum diagnosed 2009-2013. Relative survival (RS) was estimated using the Ederer II method. Simple and multivariable analyses were estimated by Poisson regression models.

RESULTS

Of 5627 women identified, 1246 (22%) had borderline tumors and 4381 had malignant tumors. In total, 2359 women had serous cancer; 71% originated in the ovary (OC), 9% in the fallopian tube (FTC), 9% in the peritoneum (PPC) and 11% at an undesignated primary site (UPS). Estimated RS at 5-years was 37%; for FTC 54%, 40% for OC, 34% for PPC and 13% for UPS. In multivariable regression analyses restricted to women who had undergone primary or interval debulking surgery for OC, FTC and PPC, site of origin was not independently associated with survival. Significant associations with worse survival were found for advanced stages (RR 2.63, P<0.001), moderate (RR 1.90, P<0.047) and poor differentiation (RR 2.20, P<0.009), neoadjuvant chemotherapy (RR1.33, P<0.022), residual tumor (RR 2.65, P<0.001) and platinum single (2.34, P<0.001) compared to platinum combination chemotherapy.

CONCLUSION

Survival was poorer for serous cancer at UPS than for ovarian, fallopian tube and peritoneal cancer. Serous cancer at UPS needs to be addressed when reporting and comparing survival rates of ovarian cancer.

Transanal total mesorectal excision (taTME) for rectal cancer: a systematic review and meta-analysis of oncological and perioperative outcomes compared with laparoscopic total mesorectal excision

Background

Transanal total mesorectal excision (taTME) is an emerging surgical technique for rectal cancer. However, the oncological and perioperative outcomes are controversial when compared with conventional laparoscopic total mesorectal excision (laTME).

Methods

A systematic review and meta-analysis based on Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines was conducted in PubMed, Embase and Cochrane database. All original studies published in English that compared taTME with laTME were included for critical appraisal and meta-analysis. Data synthesis and statistical analysis were carried out using RevMan 5.3 software.

Results

A total of seven studies including 573 patients (taTME group = 270; laTME group = 303) were included in our meta-analysis. Concerning the oncological outcomes, no differences were observed in harvested lymph nodes, distal resection margin (DRM) and positive DRM between the two groups. However, the taTME group showed a higher rate of achievement of complete grading of mesorectal quality (OR = 1.75, 95% CI = 1.02–3.01, P = 0.04), a longer circumferential resection margin (CRM) and less involvement of positive CRM (CRM: WMD = 0.96, 95% CI = 0.60–1.31, P <0.01; positive CRM: OR = 0.39, 95% CI = 0.17–0.86, P = 0.02). Concerning the perioperative outcomes, the results for hospital stay, intraoperative complications and readmission were comparable between the two groups. However, the taTME group showed shorter operation times (WMD = –23.45, 95% CI = –37.43 to –9.46, P <0.01), a lower rate of conversion (OR = 0.29, 95% CI = 0.11–0.81, P = 0.02) and a higher rate of mobilization of the splenic flexure (OR = 2.34, 95% CI = 0.99–5.54, P = 0.05). Although the incidence of anastomotic leakage, ileus and urinary morbidity showed no difference between the groups, a significantly lower rate of overall postoperative complications (OR = 0.65, 95% CI = 0.45–0.95, P = 0.03) was observed in the taTME group.

Conclusions

In comparison with laTME, taTME seems to achieve comparable technical success with acceptable oncologic and perioperative outcomes. However, multicenter randomized controlled trials are required to further evaluate the efficacy and safety of taTME.