Immediate surgery or clinical follow-up after a complete clinical response?

Surveillance strategies following curative resection and non-operative approach of rectal cancer: How and how long? Review of current recommendations

Different follow-up strategies are available for patients with rectal cancer following curative treatment. A combination of biochemical testing and imaging investigation, associated with physical examination are commonly used. However, there is currently no consensus about the types of tests to perform, the timing of the testing, and even the need for follow-up at all has been questioned. The aim of this study was to review the evidence of the impact of different follow-up tests and programs in patients with non-metastatic disease after definitive treatment of the primary. A literature review was performed of studies published on MEDLINE, EMBASE, the Cochrane Library and Web of Science up to November 2022. Current published guidelines from the most authoritative specialty societies were also reviewed. According to the follow-up strategies available, the office visit is not efficient but represents the only way to maintain direct contact with the patient and is recommended by all authoritative specialty societies. In colorectal cancer surveillance, carcinoembryonic antigen represents the only established tumor marker. Abdominal and chest computed tomography scan is recommended considering that the liver and lungs are the most common sites of recurrence. Since local relapse in rectal cancer is higher than in colon cancer, endoscopic surveillance is mandatory. Different follow-up regimens have been published but randomized comparisons and meta-analyses do not allow to determine whether intensive or less intensive follow-up had any significant influence on survival and recurrence detection rate. The available data do not allow the drawing of final conclusions on the ideal surveillance methods and the frequency with which they should be applied. It is very useful and urgent for clinicians to identify a cost-effective strategy that allows early identification of recurrence with a special focus for high-risk patients and patients undergoing a “watch and wait” approach.

Nomogram for prediction of pathologic complete remission using biomarker expression and endoscopic finding after preoperative chemoradiotherapy in rectal cancer

Objective

The aim of this study is to develop a nomogram for prediction of pathologic complete remission (pCR) after preoperative chemoradiotherapy (CRT) for rectal cancer.

Methods

mRNA expression levels of seven molecular markers [p53, p21, Ki-67, vascular endothelial growth factor (VEGF), CD133, CD24, CD44] were measured by reverse transcriptase polymerase chain reaction (RT-PCR) in 120 rectal cancers. Endoscopic findings of clinical complete remission (cCR) and biologic variables were used to construct nomogram in the training group (n=80), which was validated in the validation group (n=40).

Results

mRNA expression levels of four markers (p53, p21, Ki67, CD133) correlated with pCR (24/80, 30.0%) in the training group. Low expression of p53 and/or high expression of p21, Ki67 and CD133 showed greater pCR rate. pCR was shown in 18 (69.2%) of 26 cases showing endoscopic cCR in the training group. Higher pCR rate was demonstrated in lower tumor location than middle tumor (19/49, 38.8% vs. 5/31, 16.1%). A nomogram for prediction of pCR was developed from the multivariate prediction model using these six variables, which showed good discrimination ability in the training group [area under the curve (AUC)=0.945] and validation group (AUC=0.922). The calibration plot showed good agreement between actual and predicted pCR in both patient groups.

Conclusions

Nomogram for assessment of pCR can be useful for making treatment decisions after CRT according to predicted responses.

Definitive Chemoradiation for Rectal Cancer: Is There a Role for Dose Escalation? A National Cancer Database Study

BACKGROUND

Surgery remains the standard of care in rectal cancer. Select patients will not undergo surgery for reasons such as medical inoperability or a watch-and-wait approach and instead are managed with definitive chemoradiation.

OBJECTIVE

We used the National Cancer Database to identify overall survival and predictors thereof in the nonoperative management of patients with rectal cancer.

DESIGN

This was a retrospective review.

SETTINGS

This study used deidentified data from the National Cancer Database.

PATIENTS

We queried the national cancer database from 2004 to 2014 for stage 1 to 3 rectal adenocarcinoma treated with only chemotherapy and radiation to definitive doses. Dose escalated therapy was defined as >54 Gy.

MAIN OUTCOME MEASURES

Univariable and multivariable analyses were performed to identify sociodemographic, treatment, and tumor characteristics predictive of dose escalation and overall survival. Propensity-adjusted Cox proportional hazard ratios for survival were used to account for indication bias.

RESULTS

Among the 6311 patients eligible for the study, 11% were treated with doses >54 Gy. Earlier stage and increased age/comorbidity patients were more likely to receive dose escalation, and patients with more recent treatment and treatment at an academic facility were less likely. The median follow-up time was 31 months (range, 2-154 mo). Three- and 5-year overall survival rates for all patients were 60% and 46%. Patients treated with dose escalation had a median survival of 33 months compared with 56 months for those treated with ≤54 Gy (p < 0.0001).

LIMITATIONS

The main limitation is the inherent selection bias present in National Cancer Database studies. Important treatment details and outcomes as they relate to a definitive chemoradiation approach in rectal cancer are lacking. Salvage therapy was also not recorded, which in this population could be surgery.

CONCLUSIONS

In this analysis, dose escalation in the nonoperative management of rectal cancer was associated with a lower overall survival compared with more conventional doses. Careful patient selection and enrollment on appropriate clinical trials may be warranted in the nonoperative setting. See Video Abstract at http://links.lww.com/DCR/B15. LA QUIMIORRADIACIÓN DEFINITIVA PARA EL CÁNCER RECTAL: ¿HAY LUGAR PARA EL AUMENTO DE LA DOSIS? UN ESTUDIO DE BASE DE DATOS NACIONAL DEL CÁNCER:: La cirugía sigue siendo el estándar en el tratamiento del cáncer rectal. Algunos pacientes no son quirúrgicos por razones como, no ser operables o con el enfoque de ver y esperar, y en su lugar son tratados con la quimiorradiación definitiva.Utilizamos la base de datos nacional del cáncer para identificar la supervivencia general y los factores predictivos de la misma, en el tratamiento no quirúrgico de pacientes con cáncer rectal.Esta fue una revisión retrospectiva.Utilizamos los datos identificados en la base de datos nacional del cáncer.Se consultó la base de datos nacional del cáncer del 2004-2014, para adenocarcinoma rectal en estadio 1-3, tratada únicamente con quimioterapia y radiación hasta la dosis definitiva. La terapia de aumento de la dosis se definió como >54 Gy.Se realizaron análisis univariables y multivariables para identificar características sociodemográficas, de tratamiento y predictivas del aumento de la dosis y supervivencia en general. Los índices de riesgo proporcionales de Cox ajustados a la propensión para la supervivencia, se utilizaron para tener en cuenta el sesgo de indicación.Entre los 6311 pacientes elegibles para el estudio, el 11% fue tratado con dosis >54 Gy. Los pacientes en estadios tempranos y con mayor edad/comorbilidad, tenían más probabilidades de recibir aumento de la dosis, y menos propensos los pacientes con tratamientos recientes y de centros académicos. El tiempo medio de seguimiento fue de 31 meses (2-154 meses). Las tasas de supervivencia global de tres y cinco años para todos los pacientes, fueron respectivamente del 60% y 46%. Los pacientes tratados con aumento de la dosis, tuvieron una supervivencia media de 33 meses, en comparación con los 56 meses para los pacientes tratados con ≤54 Gy (p < 0,0001).La principal limitación es el inherente sesgo en la selección, presente en los estudios de la base de datos nacional del cáncer. Faltan los detalles importantes del tratamiento y los resultados en relación con el enfoque definitivo de quimiorradiación en cáncer rectal. Tampoco se registró la terapia de rescate, que en esta población podría ser la cirugía.En este análisis, el aumento de la dosis en el manejo no quirúrgico del cáncer rectal, se asoció con una menor supervivencia global, en comparación con la dosis más convencional. La cuidadosa selección del paciente y la inscripción en los apropiados ensayos clínicos, pueden estar justificados en el entorno no quirúrgico. Vea el Resumen del Video en http://links.lww.com/DCR/B15.

Biomarker-Based Scoring System for Prediction of Tumor Response After Preoperative Chemoradiotherapy in Rectal Cancer by Reverse Transcriptase Polymerase Chain Reaction Analysis

BACKGROUND

Numerous molecular markers have been investigated to predict tumor response after preoperative chemoradiotherapy for rectal cancer.

OBJECTIVE

This study aimed to evaluate the predictive value of biomarkers for the prediction of tumor response after preoperative chemoradiotherapy.

DESIGN & SETTING

Tumor specimens have been collected prospectively from 80 patients with rectal cancer who underwent curative resection at 8 weeks after completing preoperative chemoradiotherapy.

MAIN OUTCOME MEASURES

With the use of reverse transcriptase polymerase chain reaction analysis, mRNA expression levels of 7 candidate biomarkers (p53, p21, Ki-67, VEGF, CD133, CD24, and CD44) were evaluated from fresh tumor samples collected before preoperative chemoradiotherapy. The correlation between biomarker expression levels and the pathologic response was assessed based on histopathological staging (pTNM) and tumor regression grade.

RESULTS

The mRNA expression levels of 4 biomarkers (p53, p21, Ki67, and CD133) significantly correlated with tumor regression grade response and pathologic complete response. Patients showing low expression of p53 and/or high expression of p21, Ki67, and CD133 exhibited a significantly greater tumor regression grade response and pathologic complete response rate. A scoring system devised so that 1 point was given for each biomarker whose expression level correlated with pathologic complete response (score range: 0-4) showed that 9 of 62 patients with scores of 0 to 2 achieved pathologic complete response, whereas 15 of 18 patients with scores of 3 to 4 achieved pathologic complete response (14.5% vs 83.3%, p < 0.001). For prediction of pathologic complete response, the scoring system showed 62.5% sensitivity, 94.6% specificity, an 83.3% positive predictive value, and an 85.5% negative predictive value.

LIMITATIONS

Small patient numbers have limitations related to the reproducibility and ability to provide quantitative information. In addition, this study lacks test and validation sets.

CONCLUSIONS

The pretreatment mRNA expression levels of 4 biomarkers correlated with pathologic tumor response after intraoperative chemoradiotherapy in rectal cancer. Furthermore, the scoring system combining values of biomarker expression might have predictive power with high positive and negative predictive values.

Definitive high-dose radiotherapy with concurrent chemotherapy for locally advanced rectal cancer: A case report and literature review

BACKGROUND

Standard management for locally advanced rectal cancer (LARC) involves preoperative chemoradiotherapy (CRT) and radical surgery. However, this level of treatment may be unnecessary for a subgroup of LARC patients. Previous reports have shown that approximately 20% of LARC patients experience a complete tumor response to preoperative CRT. Post-CRT nonoperative management of these patients may prevent morbidities associated with radical surgery. To our knowledge, this case report firstly presents the favorable long-term outcomes of a LARC patient who underwent definitive aim CRT.

METHODS

The patient was 73 years' old, and staging workups revealed T3N2bM0 rectal adenocarcinoma. He agreed to receive CRT, but refused surgery. A radiotherapy (RT) dose of 64.8 Gy was prescribed, which was higher than conventional (50.4 Gy) preoperative aim RT. The regimen of concurrent chemotherapy was the same as that used in preoperative aim CRT: 2 cycles of 5-fluorouracil and leucovorin.

RESULTS

Three months after CRT completion, a complete tumor response was identified clinically. Colonoscopic biopsy after 1 year showed no tumor cells. This patient is alive after 4 years with no evidence of recurrence or severe toxicity.

CONCLUSION

The long-term outcomes of this case indicate the feasibility of definitive high-dose RT with concurrent chemotherapy for LARC.

Magnetic Resonance Tumor Regression Grade and Residual Mucosal Abnormality as Predictors for Pathological Complete Response in Rectal Cancer Postneoadjuvant Chemoradiotherapy

BACKGROUND

Pathological complete response after chemoradiotherapy for rectal cancer occurs in 10% to 30% of patients. The best method to identify such patients remains unclear. Clinical assessment of residual mucosal abnormality is considered the most accurate method. In our institution, magnetic resonance tumor regression grade is performed as routine to assess response.

OBJECTIVE

The purpose of this study was to compare the sensitivity of magnetic tumor regression grade against residual mucosal abnormality in detecting patients with a pathological complete response.

DESIGN

Magnetic tumor regression grade scores from reported posttreatment MRI scans were documented. Magnetic tumor regression grade 1 to 3 was defined as likely to predict complete or near complete response. Gross appearances of the mucosa were derived from histopathology reports and used as a surrogate for clinical assessment (previously validated). Final histopathological staging was used to determine response.

SETTINGS

The study was conducted at Royal Marsden National Health Service Trust, United Kingdom.

PATIENTS

A total of 143 patients with rectal adenocarcinoma, diagnosed between September 1, 2009, and September 1, 2013, who received neoadjuvant chemoradiotherapy before curative surgery were included.

MAIN OUTCOME MEASURES

The sensitivity of magnetic tumor regression grade and residual mucosal abnormality in detecting patients with pathological complete response were measured

RESULTS

: Eighteen patients had a pathological complete response. Seventeen were detected using magnetic resonance tumor regression grade 1 to 3, with sensitivity 94% (95% CI, 0.74-0.99), and 10 were detected using residual mucosal abnormality, with sensitivity 62% (95% CI, 0.38-0.81). There was no statistical difference between the false positive rates for either method. Magnetic tumor regression grade identified 10 times more patients with a pathological complete response (diagnostic OR = 10.2 (95% CI, 1.30-73.73)) compared with clinical assessment with RMA.

LIMITATIONS

Residual mucosal abnormality was used as a surrogate marker for endoscopic appearances.

CONCLUSIONS

Most patients with rectal cancer who have a pathological complete response do not manifest a complete response at the mucosal level. Magnetic tumor regression grade is able to identify 10 times more patients than clinical assessment, with no significant compromise in the false positive rate.