Is follow-up CT imaging of the chest and abdomen necessary after preoperative neoadjuvant therapy in rectal cancer patients without evidence of metastatic disease at diagnosis?

Clinical Robotic Surgery Association (India Chapter) and Indian rectal cancer expert group’s practical consensus statements for surgical management of localized and locally advanced rectal cancer

Introduction

There are standard treatment guidelines for the surgical management of rectal cancer, that are advocated by recognized physician societies. But, owing to disparities in access and affordability of various treatment options, there remains an unmet need for personalizing these international guidelines to Indian settings.

Methods

Clinical Robotic Surgery Association (CRSA) set up the Indian rectal cancer expert group, with a pre-defined selection criterion and comprised of the leading surgical oncologists and gastrointestinal surgeons managing rectal cancer in India. Following the constitution of the expert Group, members identified three areas of focus and 12 clinical questions. A thorough review of the literature was performed, and the evidence was graded as per the levels of evidence by Oxford Centre for Evidence-Based Medicine. The consensus was built using the modified Delphi methodology of consensus development. A consensus statement was accepted only if ≥75% of the experts were in agreement.

Results

Using the results of the review of the literature and experts’ opinions; the expert group members drafted and agreed on the final consensus statements, and these were classified as “strong or weak”, based on the GRADE framework.

Conclusion

The expert group adapted international guidelines for the surgical management of localized and locally advanced rectal cancer to Indian settings. It will be vital to disseminate these to the wider surgical oncologists and gastrointestinal surgeons’ community in India.

What Is the Utility of Restaging Imaging for Patients With Clinical Stage II/III Rectal Cancer After Completion of Neoadjuvant Chemoradiation and Prior to Proctectomy?

BACKGROUND

In the United States, patients with clinical stage II or III rectal cancer typically receive neoadjuvant chemoradiation therapy (chemo/XRT) over a 5-6 week period followed by a 6-10 week break prior to proctectomy. In the current study, we evaluate the utilization of restaging studies performed and detection of disease progression during this window.

METHODS

A retrospective review of patients with clinical stage II/III rectal cancer was performed. Medical records were analyzed to collect clinicopathologic data and the performance and results of preoperative, early postoperative, and first surveillance CT and/or PET/CT in patients completing long course neoadjuvant chemo/XRT and undergoing proctectomy.

RESULTS

Between 2005 and 2017, 176 patients with clinical stage II or III rectal adenocarcinoma completed neoadjuvant chemo/XRT and underwent proctectomy. Preoperative restaging with CT CAP and/or CT/PET was performed in 72 (40.9%) patients with no detection of disease progression. Of the 104 patients without preoperative restaging, 1 had intraoperative detection of liver metastases and 31 had early postoperative reimaging (within 30 days of proctectomy) of which 2 had detection of new pulmonary metastases. Among 72 patients with no preoperative or early postoperative reimaging, first surveillance imaging was available in 47 and detected new metastases in 8 (17%).

DISCUSSION

In patients with clinical stage II/III rectal cancer who undergo long course neoadjuvant chemo/XRT, perioperative reimaging with CT CAP and/or PET/CT detects new metastases in a small percentage of patients. A multi-institutional, prospective analysis using standardized staging protocols is warranted to better determine the value of preoperative restaging in these patients.

Limited Role for Routine Restaging After Neoadjuvant Therapy in Locally Advanced Rectal Cancer

BACKGROUND

Although many patients with locally advanced rectal cancer undergo restaging imaging after neoadjuvant chemoradiotherapy and before surgery, the benefit of this practice is unclear. The purpose of this study was to examine the impact of reimaging on outcomes.

MATERIALS AND METHODS

We performed a retrospective analysis of consecutive patients with stage 2 and 3 rectal adenocarcinoma treated with neoadjuvant chemoradiotherapy between May 2005 and April 2018. Patient and disease characteristics, imaging, treatment, and oncologic outcomes were compared between those who underwent restaging and those who went directly to surgery. Predictors of outcomes and cost effectiveness of restaging were determined.

RESULTS

Of 224 patients, 146 underwent restaging. Six restaged patients had findings leading to a change in management. There was no difference in freedom from recurrence (P = 0.807) and overall survival (P = 0.684) based on restaging. Pretreatment carcinoembryonic antigen level >3 ng/mL (P = 0.010), clinical T stage 4 (P = 0.016), and pathologic T4 (P = 0.047) and N2 (P = 0.002) disease increased the risk of death, whereas adjuvant chemotherapy decreased the risk of death (P < 0.001) on multivariate analysis. Disease recurrence was lower with pelvic exenteration (P = 0.005) and in females (P = 0.039) and higher with pathologic N2 (P = 0.003) and N3 (P = 0.002) disease. The average cost of reimaging is $40,309 per change in management; however, $45 is saved per patient when downstream surgical costs are considered.

CONCLUSIONS

Imaging restaging after neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer rarely changes treatment and does not improve survival. In a subset of patients at higher risk for worse outcome, reimaging may be beneficial.

Restaging Patients with Rectal Cancer Following Neoadjuvant Chemoradiation: A Systematic Review

BACKGROUND

In the USA, most patients with clinical stage II/III rectal cancer receive neoadjuvant chemoradiation (chemo/XRT) over 5-6 weeks followed by a 6-10-week break before proctectomy. As chemotherapy is delivered at radio-sensitizing doses, there is essentially a 3-month window during which potential systemic disease is untreated. Evidence regarding the utility of restaging patients prior to proctectomy is limited.

METHODS

PubMed, Scopus, Web of Science, and the Cochrane Library were searched for studies evaluating the utility of restaging patients with rectal cancer after completion of long-course chemo/XRT, and reporting associated changes in management. Studies that were non-English, included <50 patients, or examining the diagnostic accuracy of imaging modalities were excluded. Study quality was evaluated using the modified Newcastle Ottawa Scale.

RESULTS

Eight studies were identified including a total of 1251 patients restaged between completion of chemo/XRT and proctectomy. All studies were retrospective. Restaging identified new metastatic disease in 72 (6.0%) patients, with 4 studies reporting specific sites: liver (n = 28), lung (n = 8), adrenal (n = 1), bone (n = 1), and multiple sites (n = 7). Overall progression (distant or local) was detected in 88 (7.0%) patients and resulted in a change in management in 77 (87.5%) of these patients. Tumor-related prognostic characteristics were inconsistently reported among studies, precluding meta-analysis.

CONCLUSIONS

Although restaging between completion of neoadjuvant chemo/XRT and proctectomy detects disease progression in only a small percentage of patients, findings alter the treatment plan in the vast majority of these patients. Multi-institutional collaboration with analysis of well-defined prognostic variables may better identify patients most likely to benefit from restaging.

Early Systemic Failure After Preoperative Chemoradiotherapy for the Treatment of Patients With Rectal Cancer

Purpose

Distant metastasis can occur early after neoadjuvant chemoradiotherapy (CRT) in patients with rectal cancer. This study was conducted to evaluate the clinical characteristics of patients who developed early systemic failure.

Methods

The patients who underwent neoadjuvant CRT for a rectal adenocarcinoma between June 2007 and July 2015 were included in this study. Patients who developed distant metastasis within 6 months after CRT were identified. We compared short- and long-term clinicopathologic outcomes of patients in the early failure (EF) group with those of patients in the control group.

Results

Of 107 patients who underwent neoadjuvant CRT for rectal cancer, 7 developed early systemic failure. The lung was the most common metastatic site. In the EF group, preoperative carcinoembryonic antigen was higher (5 mg/mL vs. 2 mg/mL, P = 0.010), and capecitabine as a sensitizer of CRT was used more frequently (28.6% vs. 3%, P = 0.002). Of the 7 patients in the EF group, only 4 underwent a primary tumor resection (57.1%), in contrast to the 100% resection rate in the control group (P < 0.001). In terms of pathologic outcomes, ypN and TNM stages were more advanced in the EF group (P < 0.001 and P = 0.047, respectively), and numbers of positive and retrieved lymph nodes were much higher (P < 0.001 and P = 0.027, respectively).

Conclusion

Although early distant metastasis after CRT for rectal cancer is very rare, patients who developed early metastasis showed a poor nodal response with a low primary tumor resection rate and poor oncologic outcomes.

Restaging after neoadjuvant chemoradiation in rectal cancers: is histology the key in patient selection?

BACKGROUND

Neoadjuvant chemoradiation is the standard of care for locally advanced rectal cancer. However, there is no clarity regarding the necessity for restaging scans to rule out systemic progression of disease post chemoradiation with existing literature being divided on the need for the same.

METHODS

Data from a prospectively maintained database was retrospectively analysed. All locally advanced rectal cancers (node positive/T4/T3 with threatened or involved CRM) were included. Biopsy proof of adenocarcinoma and CT scan of abdomen and chest were mandatory. Grade of tumor and response to CTRT on restaging magnetic resonance imaging (MRI) were documented.

RESULTS

Out of 119 patients subjected to CTRT, 72 underwent definitive total mesorectal excision while 13 patients progressed locoregionally on restaging MR pelvis and 15 other patients progressed systemically while the rest defaulted. Patients with poorly differentiated (PD) cancers were compared to those with well/moderately differentiated (WMD) tumors. PD tumors had a significantly higher rate of local progression (32.1% vs. 5.6% %, P=0.0011) and systemic progression (35.7% vs. 6.9%, P=0.0008) as compared to WMD tumors. Only one-third (9/28) of PD patients underwent TME while the rest progressed.

CONCLUSIONS

Selecting poorly differentiated tumors alone for restaging CECT abdomen and thorax will be a cost effective strategy as the rate of progression is very high. Also patients with PD tumors need to be consulted about the high probability of progression of disease.