Effectiveness of adjuvant radiotherapy after local excision of rectal cancer with deep submucosal invasion: a single-hospital, case-control analysis

Risk of recurrence after local resection of T1 rectal cancer: a meta-analysis with meta-regression

BACKGROUND

T1 rectal cancer (RC) patients are increasingly being treated by local resection alone but uniform surveillance strategies thereafter are lacking. To determine whether different local resection techniques influence the risk of recurrence and cancer-related mortality, a meta-analysis was performed.

METHODS

A systematic search was conducted for T1RC patients treated with local surgical resection. The primary outcome was the risk of RC recurrence and RC-related mortality. Pooled estimates were calculated using mixed-effect logistic regression. We also systematically searched and evaluated endoscopically treated T1RC patients in a similar manner.

RESULTS

In 2585 unique T1RC patients (86 studies) undergoing local surgical resection, the overall pooled cumulative incidence of recurrence was 9.1% (302 events, 95% CI 7.3-11.4%; I2 = 68.3%). In meta-regression, the recurrence risk was associated with histological risk status (p < 0.005; low-risk 6.6%, 95% CI 4.4-9.7% vs. high-risk 28.2%, 95% CI 19-39.7%) and local surgical resection technique (p < 0.005; TEM/TAMIS 7.7%, 95% CI 5.3-11.0% vs. other local surgical excisions 10.8%, 95% CI 6.7-16.8%). In 641 unique T1RC patients treated with flexible endoscopic excision (16 studies), the risk of recurrence (7.7%, 95% CI 5.2-11.2%), cancer-related mortality (2.3%, 95% CI 1.1-4.9), and cancer-related mortality among patients with recurrence (30.0%, 95% CI 14.7-49.4%) were comparable to outcomes after TEM/TAMIS (risk of recurrence 7.7%, 95% CI 5.3-11.0%, cancer-related mortality 2.8%, 95% CI 1.2-6.2% and among patients with recurrence 35.6%, 95% CI 21.9-51.2%).

CONCLUSIONS

Patients with T1 rectal cancer may have a significantly lower recurrence risk after TEM/TAMIS compared to other local surgical resection techniques. After TEM/TAMIS and endoscopic resection the recurrence risk, cancer-related mortality and cancer-related mortality among patients with recurrence were comparable. Recurrence was mainly dependent on histological risk status.

Local Excision ± Chemoradiotherapy vs. Total Mesorectal Excision for Early Rectal Cancer: Case-Matched Analysis of Long-Term Results

Background: Our aim was to compare the bowel function and oncologic outcomes following these two treatment modalities. Materials and methods: This was a single-center study with 67 patients included between 2009 and 2018. A total of 32 patients underwent total mesorectal excision (TME) group and 35 transanal local excisions (LE) ± chemoradiation. We performed a case-matched analysis: we matched the patients by age, cancer stage, and comorbidities. Duration of operation, postoperative complications, length of hospital stay, and long-term functional and oncological outcomes were compared. We calculated oncological outcomes using Kaplan-Meier Cox diagrams. In addition, we used a low anterior resection syndrome (LARS) score for the bowel function assessment. Results: Mean operation time in the LE group was 58.8 ± 45 min compared with the TME group that was 121.1 ± 42 min (p = 0.032). Complications were seen in 5.7% in LE group and 15.62% in TME group (p = 0.043). ~85.2% of the patients had no LARS in LE group compared with 54.5% in TME group (p = 0.018). Minor LARS was 7.4% in LE group compared with 31.8% in TME group (p = 0.018); major LARS was 7.4 and 13.7%, respectively (p = 0.474). Hospital stay was 2.77 days in LE group compared with 9.21 days in TME group (p = 0.036). The overall survival was 68.78 months in LE group compared with 74.81 months in TME group (p = 0.964). Conclusion: Our results of a small sample size showed that local excision ± chemoradiation is a rather safe method for early rectal cancer compared with gold standard treatment. In addition, better bowel function is preserved with less postoperative complications and shorter hospital stays.

Long-term outcomes of patients with poor prognostic factors following transanal endoscopic microsurgery for early rectal cancer

AIM

Management of early rectal cancer following transanal microscopic anal surgery poses a management dilemma when the histopathology reveals poor prognostic features, due to high risk of local recurrence. The aim of this study is to evaluate the oncological outcomes of such patients who undergo surgery with total mesorectal excision (TME), receive adjuvant chemo/radiotherapy (CRDT/RT) or receive close surveillance only (no further treatment).

METHODS

We identified patients with poor prognostic factors-pT2 adenocarcinoma, poor differentiation, deep submucosal invasion (Kikuchi SM3), lymphovascular invasion, tumour budding or R1 resection margin-between 1 September 2012 and 31 January 2020 and report their oncological outcomes.

RESULTS

Of the 53 patients, 18 had TME, 14 had CRDT and 14 had RT; seven patients did not have any further treatment. The median follow-up was 48 months, 12 developed recurrence and six died. Overall, 5-year survival (OS) was 88.9% and disease-free survival (DFS) was 79.2%. Compared to the surgical group, in which there were eight recurrences and two deaths, there were zero recurrences or deaths in the CRDT group, log-rank test P = 0.206 for OS and P = 0.005 for DFS. The 5-year survival rates in the RT and surveillance only groups were OS 78.6%, DFS 85.7% and OS 71.5%, DFS 71% respectively. TME assessment in the surgical group revealed Grade 3 quality in seven of the 16 available reports.

CONCLUSION

These findings support the strategy of adjuvant CRDT as first line treatment for patients undergoing transanal endoscopic microsurgery for early rectal cancer with poor prognostic factors on initial histological assessment.

Early-rectal Cancer Treatment: A Decision-tree Making Based on Systematic Review and Meta-analysis

Local excision (LE) has arisen as an alternative to total mesorectal excision for the treatment of early rectal cancer. Despite a decreased morbidity, there are still concerns about LE outcomes. This systematic-review and meta-analysis design is based on the "PICO" process, aiming to answer to three questions related to LE as primary treatment for early-rectal cancer, the optimal method for LE, and the potential role for completion treatment in high-risk histology tumors and outcomes of salvage surgery. The results revealed that reported overall survival (OS) and disease-specific survival (DSS) were 71%-91.7% and 80%-94% for LE, in contrast to 92.3%-94.3% and 94.4%-97% for radical surgery. Additional analysis of National Database studies revealed lower OS with LE (HR: 1.26; 95%CI, 1.09-1.45) and DSS (HR: 1.19; 95%CI, 1.01-1.41) after LE. Furthermore, patients receiving LE were significantly more prone develop local recurrence (RR: 3.44, 95%CI, 2.50-4.74). Analysis of available transanal surgical platforms was performed, finding no significant differences among them but reduced local recurrence compared to traditional transanal LE (OR:0.24;95%CI, 0.15-0.4). Finally, we found poor survival outcomes for patients undergoing salvage surgery, favoring completion treatment (chemoradiotherapy or surgery) when high-risk histology is present. In conclusion, LE could be considered adequate provided a full-thickness specimen can be achieved that the patient is informed about risk for potential requirement of completion treatment. Early-rectal cancer cases should be discussed in a multidisciplinary team, and patient's preferences must be considered in the decision-making process.

Local recurrence after local excision of early rectal cancer: a meta-analysis of completion TME, adjuvant (chemo)radiation, or no additional treatment

BACKGROUND

The risks of local recurrence and treatment-related morbidity need to be balanced after local excision of early rectal cancer. The aim of this meta-analysis was to determine oncological outcomes after local excision of pT1-2 rectal cancer followed by no additional treatment (NAT), completion total mesorectal excision (cTME) or adjuvant (chemo)radiotherapy (aCRT).

METHODS

A systematic search was conducted in PubMed, Embase and the Cochrane Library. The primary outcome was local recurrence. Statistical analysis included calculation of the weighted average of proportions.

RESULTS

Some 73 studies comprising 4674 patients were included in the analysis. Sixty-two evaluated NAT, 13 cTME and 28 aCRT. The local recurrence rate for NAT among low-risk pT1 tumours was 6·7 (95 per cent c.i. 4·8 to 9·3) per cent. There were no local recurrences of low-risk pT1 tumours after cTME or aCRT. The local recurrence rate for high-risk pT1 tumours was 13·6 (8·0 to 22·0) per cent for local excision only, 4·1 (1·7 to 9·4) per cent for cTME and 3·9 (2·0 to 7·5) per cent for aCRT. Local recurrence rates for pT2 tumours were 28·9 (22·3 to 36·4) per cent with NAT, 4 (1 to 13) per cent after cTME and 14·7 (11·2 to 19·0) per cent after aCRT.

CONCLUSION

There is a substantial risk of local recurrence in patients who receive no additional treatment after local excision, especially those with high-risk pT1 and pT2 rectal cancer. The lowest recurrence risk is provided by cTME; aCRT has outcomes comparable to those of cTME for high-risk pT1 tumours, but shows a higher risk for pT2 tumours.

Radiation therapy for rectal cancer

Radiotherapy (RT) has remained an important pillar in the multi-modality management of rectal cancer. Adjuvant RT with concurrent chemotherapy (chemo-RT) was once the standard of care for locally advanced rectal cancer, but with time, that has now changed and neoadjuvant chemo-RT followed by total mesorectal excision (TME) surgery is the new standard. Alternatively, neoadjuvant RT alone remains an option and clinicians are tasked to choose between the two. In an era of personalised oncological management, it is unsurprising that the treatment for rectal cancer is following suit and upcoming trials are studying ways to improve outcomes and minimise toxicity for patients while tailoring treatments specific to each patient's tumour. We review the evolution of the role of RT in rectal cancer and look forward to what the future holds.

Long-term Transanal Excision Outcomes in Patients With T1 Rectal Cancer: Comparative Analysis of Radical Resection

Purpose

Transanal excision (TAE) is an alternative surgical procedure for early rectal cancer. This study compared long-term TAE outcomes, in terms of survival and local recurrence (LR), with total mesorectal excision (TME) in patients with pathologically confirmed T1 rectal cancer.

Methods

T1 rectal adenocarcinoma patients who underwent surgery from 1990 to 2011 were retrospectively reviewed. Patients that were suspected to have preoperative lymph node metastasis were excluded. Demographics, recurrence, and survival were analyzed based on TAE and TME surgery.

Results

Of 268 individuals, 61 patients (26%) underwent TAE, which was characterized by proximity to the anus, submucosal invasion depth, and lesion infiltration, compared with TME patients (P < 0.001–0.033). During a median follow-up of 10.4 years, 12 patients had systemic and/or LR. Ten-year cancer-specific survival in the TAE and TME groups was not significantly different (98% vs. 100%). However, the 10-year LR rate in the TAE group was greater than that of TME group (10% vs. 0%, P < 0.001). Although 5 of the 6 TAE patients with LR underwent salvage surgery, one of the patients eventually died. The TAE surgical procedure (hazard ratio, 19.066; P = 0.007) was the only independent risk factor for LR.

Conclusion

Although long-term survival after TAE was comparable to that after TME, TAE had a greater recurrence risk than TME. Thus, TAE should only be considered as an alternative surgical option for early rectal cancer in selected patients.

A systematic review of local excision followed by adjuvant therapy in early rectal cancer: are pT1 tumours the limit?

AIM

Total mesorectal excision remains the cornerstone of treatment for rectal cancer. Significant morbidity means local excision may be more appropriate in selected patients. Adjuvant therapy reduces local recurrence and improves survival; however, there is a paucity of data on its impact following local excision, which this systematic review aims to address.

METHODS

A systematic search of the MEDLINE, Embase and Cochrane databases using validated terms for rectal cancer, adjuvant therapy and local excision was performed. Included studies focused on local excision with adjuvant therapy for adenocarcinoma of the rectum. Primary outcome measures were local recurrence, survival and morbidity. Studies providing neoadjuvant therapy or local excision alone were excluded.

RESULTS

Twenty-two studies described 804 patients. Indications for local excision included favourable histology, patient choice and comorbidities. T1, T2 and T3 tumours accounted for 35.1%, 58.0% and 6.9% of cases, respectively. The most frequent local excision technique was transanal excision (77.7%). Adjuvant therapy included long-course chemoradiation or radiotherapy. Median follow-up was 51 months (range 1-165). The pooled local recurrence was 5.8% (95% CI 3.0-9.5) for pT1, 13.8% (95% CI 10.1-17.9) for pT2 and 33.7% (95% CI 19.2-50.1) for pT3 tumours. The overall median disease-free survival was 88% (range 50%-100%) with a pooled overall morbidity of 15.1% (95% CI 11.0-18.7).

CONCLUSIONS

This area remains highly relevant to modern clinical practice. The data suggest that local excision followed by adjuvant therapy can achieve acceptable long-term outcomes in high-risk pT1 tumours, but not in T2 tumours and above in whom radical surgery should be offered.

Radiotherapy dose led to a substantial prolongation of survival in patients with locally advanced rectosigmoid junction cancer: a large population based study

Radiotherapy is widely applied for locally advanced rectal cancer (RC) to improve both local control and long-term outcomes. However, the efficacy of radiotherapy for rectosigmoid junction cancer (RSC) is still undetermined. Here, we identified 10074 patients who were diagnosed with locally advanced RSC from Surveillance, Epidemiology, and End-Results (SEER) cancer registry. These patients were divided into three subgroups according to different therapy strategies, including surgery alone, surgery plus preoperative radiotherapy and surgery plus postoperative radiotherapy. 5-year cancer-specific survival (CSS) and 5-year overall survival (OS) were obtained. Kaplan-Meier methods and Cox regression models were used to estimate the correlations between prognostic factors and survival outcomes.The 5-year CSSs for RSC patients treated with pre- and postoperative radiotherapy were 72.3% and 72.2%, which were significantly higher than surgery alone (64.8%). The 5-year OSs for RSC patients treated with pre- and postoperative radiotherapy were 71.6% and 71.2%, which were higher than surgery alone (64.0%). In the separate analyses of stage II and III RSC patients, the similar trends were also obtained. In addition, pre- and postoperative radiotherapy were equally identified as valuable prognostic factors for better survival outcomes in RSC patients. Furthermore, the results following propensity score matching also confirmed that the long-term survivals of RSC patients were improved following radiotherapy. In conclusion, locally advanced RSCpatients could obtain potential long-term survival benefits from radiotherapy. A prospective randomized control trial should be performed to further validate the strength of evidence in current study.