Endoscopic Criteria for Evaluating Tumor Stage after Preoperative Chemoradiation Therapy in Locally Advanced Rectal Cancer

Is Early, Postinduction Restaging of Rectal Cancer Undergoing Total Neoadjuvant Therapy Associated With Ultimate Treatment Response?

BACKGROUND

Among patients with rectal cancer treated with total neoadjuvant therapy, it is unclear whether early, postinduction restaging is associated with final tumor response. If so, interim restaging may alter rectal cancer decision-making.

OBJECTIVE

To determine whether postinduction restaging with endoscopy and MRI is associated with final tumor response.

DESIGN

Retrospective cohort study.

SETTINGS

US tertiary care institution accredited by the National Accreditation Program for Rectal Cancer.

PATIENTS

Patients with biopsy-proven rectal cancer who underwent total neoadjuvant therapy with interim (postinduction) restaging.

MAIN OUTCOME MEASURES

Association between response assessment on postinduction restaging and final treatment response.

RESULTS

One hundred seven patients were analyzed. Patients with postinduction magnetic resonance tumor response grade 1 and 2 or complete endoscopic response were significantly more likely (OR 5.4, p < 0.01 and OR 3.7, p = 0.03, respectively) to ultimately achieve a final complete response. Likewise, the odds of a final incomplete response were significantly higher for patients with postinduction composite partial (OR 4.1, p < 0.01) or minimal (OR 12.0, p < 0.01) responses.

LIMITATIONS

Retrospective analysis and lack of detailed subclassification of partial endoscopic response may have limited the conclusions of these data. The limited sample size may also have biased these conclusions.

CONCLUSIONS

Tumor response to induction therapy is associated with the ultimate treatment response to total neoadjuvant therapy among complete or minimal responders; the significance of a partial interim response remains unclear. See Video Abstract .

EST ASOCIADA LA REESTADIFICACIN TEMPRANA POSTINDUCCIN DEL CANCER DE RECTO SOMETIDO A TERAPIA NEOADYUVANTE TOTAL CON LA RESPUESTA TERAPUTICA FINAL

ANTECEDENTES:Entre los pacientes con cáncer de recto tratados con terapia neoadyuvante total, no está claro si la re-estadificación temprana posterior a la inducción está asociada con la respuesta tumoral final. De ser así, la re-estadificación provisoria podría alterar la toma de decisiones sobre el cáncer rectal.OBJETIVO:Determinar si la re-estadificación posterior a la inducción con endoscopia y resonancia magnética están asociadas con la respuesta tumoral final.DISEÑO:Estudio de cohorte retrospectivoESCENARIO:Institución de atención terciaria de Estados Unidos, certificada por el Programa Nacional de Acreditación para el Cáncer de Recto.PACIENTES:Pacientes con cáncer rectal confirmado por biopsia que fueron sometidos a terapia neoadyuvante total con re-estadificación provisoria (posterior a la inducción).PRINCIPALES MEDIDAS DE RESULTADOS:La asociación entre la evaluación de la respuesta en la re-estadificación posterior a la inducción y la respuesta al final del tratamiento.RESULTADOS:Se estudiaron 107 pacientes. Aquellos que presentaban respuesta tumoral a la resonancia magnética post-inducción grado 1-2 o respuesta endoscópica completa tuvieron significativamente más probabilidades (OR (odds ratio) 5,4 [ p < 0,01] y OR: 3,7 [ p = 0,03], respectivamente) de lograr finalmente una respuesta completa final. Asimismo, las probabilidades de una respuesta incompleta final fueron significativamente mayores para los pacientes con respuestas parciales compuestas post-inducción (OR: 4,1, p < 0,01) o mínimas (OR: 12,0, p < 0,01).LIMITACIONES:El análisis retrospectivo y la falta de una subclasificación detallada de la respuesta endoscópica parcial pueden haber limitado las conclusiones de estos datos. El tamaño limitado de la muestra también puede haber sesgado las conclusiones mencionadas.CONCLUSIÓN:La respuesta tumoral a la terapia de inducción está asociada con la respuesta final al tratamiento con terapia neoadyuvante total entre los respondedores completos o mínimos; la importancia de una respuesta parcial provisional sigue sin estar clara. (Traducción-Dr. Xavier Delgadillo ).

The value of multimodality MR in T staging evaluation after neoadjuvant therapy for rectal cancer

BACKGROUND

Surgery is the preferred treatment for rectal cancer, but surgical treatment alone sometimes does not achieve satisfactory results.

OBJECTIVE

To explore the value of multimodal Magnetic Resonance (MR) images in evaluating T staging of rectal cancer after neoadjuvant therapy and to compare and analyze with pathological results.

METHODS

This study retrospectively analyzed 232 patients with stage T3, T4 rectal cancer between January 1, 2017 and October 31, 2022. MR examination was performed within 3 days before surgery. Different MR sequences were used for mrT staging of rectal cancer after neoadjuvant therapy and compared with pathological pT staging. The accuracy of different MR sequences in evaluating T staging of rectal cancer was calculated, and the consistency between the two was analyzed by kappa test. The sensitivity, specificity, negative predictive value and positive predictive value of different MR sequences in evaluating rectal cancer invading mesorectal fascia after neoadjuvant therapy were calculated.

RESULTS

A total of 232 patients with rectal cancer were included in the study. The accuracy of high-resolution T2 WI in evaluating T staging of rectal cancer after neoadjuvant therapy was 49.57%, and the Kappa value was 0.261. The accuracy of high-resolution T2WI combined with diffusion weighted imaging (DWI) in evaluating T staging of rectal cancer after neoadjuvant therapy was 61.64%, and the Kappa value was 0.411. The accuracy of high-resolution combined with DCE-MR images in evaluating T staging of rectal cancer after neoadjuvant therapy was 80.60%, and the Kappa value was 0.706. The sensitivity and specificity of high-resolution t2-weighted imaging (HR-T2WI) combined with dynamic contrast-enhancement magnetic resonance (DCE-MR) in evaluating the invasion of mesorectal fascia were 83.46% and 95.33%, respectively.

CONCLUSION

Compared with HR-T2WI combined with DWI images for mrT staging of rectal cancer after neoadjuvant chemoradiotherapy (N-CRT), HR-T2WI combined with DCE-M has the highest accuracy in evaluating mrT staging of rectal cancer after neoadjuvant therapy (80.60%), and has a high consistency with pathological pT staging. It is the best sequence for T staging of rectal cancer after neoadjuvant therapy. At the same time, the sequence has high sensitivity and specificity in evaluating mesorectal fascia invasion, which can provide accurate perioperative information for the formulation of surgical plan.

Clinical predictors of pathological good response in locally advanced rectal cancer

Purpose

The aim of this study was to identify the clinical predictors of pathological good response (PGR) after neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer (LARC) to clarify the indications for local excision.

Methods and materials

A total of 173 patients with LARC (cT3–4/N +) who were treated with nCRT followed by surgery were enrolled in our retrospective study. Patients were categorized into two groups according to the different tumor responses of surgical pathology. Stage ypT0–1N0 was defined as the group with PGR, and stage ypT2–4N0/ypTanyN + was the defined as the pathological poor response (PPR) group, and the potential predictors were compared.

Results

Of 173 patients, PGR was achieved in 57 patients (32.95%). The distance from the inferior margin of the tumor to the anal verge, cT classification, pretreatment carcinoembryonic antigen (CEA) and the interval from the end of radiation to surgery were correlated with pathological response. In the multivariate analysis, the distance from anal verge < 5 cm (OR = 0.443, p = 0.019), pretreatment CEA < 5 ng/mL (OR = 0.412, p = 0.015) and the interval from the end of radiation to surgery ≥ 84 days (OR = 2.652, p = 0.005) were independent predictors of PGR.

Conclusions

The distance from the inferior margin of the tumor to the anal verge, pretreatment CEA and the interval from the end of radiation to surgery were significant predictors of PGR in LARC. A prospective study is needed to further validate these results in the future.

Oncologic Risk of Rectal Preservation Against Medical Advice After Chemoradiotherapy for Rectal Cancer: A Multicenter Comparative Cross-Sectional Study with Rectal Preservation as Supported by Surgeon

BACKGROUND

Rectal preservation against medical advice after neoadjuvant chemoradiotherapy for rectal cancer may increase oncologic uncertainty. This study aimed to compare the oncologic outcomes of patients undergoing rectal preservation as intended by the surgeon, and the outcomes of patients refusing rectal resection against medical advice.

METHODS

The study population consisted of patients in whom the rectum was preserved after neoadjuvant chemoradiotherapy for clinical stage I-III mid or low rectal cancer between May 2003 and August 2017 (n = 2883); these patients were divided into those in whom rectal preservation was intended by their surgeon (intended rectal preservation, group A, n = 41) and those in whom the rectum was not resected against medical advice (unintended rectal preservation, group B, n = 101), defined as non-operative management or local excision.

RESULTS

The tumor distance, age, and performance status of patients were not significantly different between the groups, while the clinical T stage before chemoradiotherapy was lower in group A than in group B (P < 0.001). During the median follow-up period of 34 months (interquartile range 18.0-72.0 months), the 3-year overall survival in group B (59.7%) was worse than that in group A (90.1%; P < 0.001), and 80.2% of group B patients had residual or unknown disease status.

CONCLUSIONS

This study showed that unintended rectal preservation increases oncologic risk after neoadjuvant chemoradiotherapy for rectal cancer regardless of short-term follow-up. Therefore, these findings could be shared with rectal cancer patients who choose to ignore medical advice after chemoradiotherapy to preserve their rectum.

Endoscopic assessment of tumor regression after preoperative chemoradiotherapy as a prognostic marker in locally advanced rectal cancer

PURPOSE

This study was designed to evaluate tumor regression endoscopic criteria for predicting the post-chemoradiotherapy (CRT) prognosis of patients with locally advanced rectal cancer.

MATERIAL AND METHODS

A total of 425 patients with rectal cancer who received radical surgery after CRT were included in this study. All patients were divided into two groups according to post-CRT preoperative endoscopic findings: 1) good response (E-GR): scar, telangiectasia, or erythema; 2) minimal or no response (E-MR): nodules, ulcers, strictures, or remnant tumor. Cox proportional hazard models were used to analyze the effect of preoperative clinicopathological variables on disease-free survival (DFS) and overall survival (OS).

RESULTS

The independent prognostic factors for DFS were tumor location less than 5 cm from anal verge (hazard ratio [HR] 1.92, 95% confidence interval [CI] 1.27 to 2.88), pre-CRT carcinoembryonic antigen (CEA) > 5 ng/mL (HR 2.10, 95% CI 1.41 to 3.14), histologic high grade (HR 2.96, 95% CI 1.51 to 5.81), and E-GR (HR 0.26, 95% CI 0.08 to 0.83). The independent prognostic factors for OS were age over 65 years, tumor location, pre-CRT CEA, histologic grade, and E-GR (HR 0.13, 95% CI 0.02 to 0.99).

CONCLUSIONS

Post-CRT endoscopic findings were predictors of prognosis in patients with rectal cancer. If endoscopic findings are simultaneously used with certain preoperative prognostic factors, rectal cancer patients will potentially have more treatment options.