The Relevance of Radial Margin Status in Perihilar Cholangiocarcinoma: A State-of-the-Art Narrative Review.

BACKGROUND: Prognosis of perihilar cholangiocarcinoma (PHCC) is poor, and curative-intent resection is the most effective treatment associated with long-term survival. Surgery is technically demanding since it involves a major hepatectomy with en bloc resection of the caudate lobe and extrahepatic bile duct. Furthermore, to achieve negative margins, it may be necessary to perform concomitant vascular resection or pancreatoduodenectomy. Despite this aggressive approach, recurrence is often observed, considering 5-year recurrence-free survival below 15% and 5-year overall survival that barely exceeds 40%. SUMMARY: The literature reports that survival rates are better in patients with negative margins, and surprisingly, R0 resections range between 19% and 95%. This variability is probably due to different surgical strategies and the pathologist's expertise with specimens. In fact, a proper pathological examination of residual disease should take into consideration both the ductal and the radial margin (RM) status. Currently, detailed pathological reports are lacking, and there is a likelihood of misinterpreting residual disease status due to the missing of RM description and the utilization of various definitions for surgical margins. KEY MESSAGES: The aim of PHCC surgery is to achieve negative margins including RM. More clarity in reporting on RM is needed to define true radical resection and consistent design of oncological studies for adjuvant treatments.

Multicenter phase II trial of transanal total mesorectal excision for rectal cancer: preliminary results.

BACKGROUND: Transanal TME (taTME) combines abdominal and transanal dissection to facilitate sphincter preservation in patients with low rectal tumors. Few phase II/III trials report long-term oncologic and functional results. We report early results from a North American prospective multicenter phase II trial of taTME (NCT03144765). METHODS: 100 patients with stage I-III rectal adenocarcinoma located ≤ 10 cm from the anal verge (AV) were enrolled across 11 centers. Primary and secondary endpoints were TME quality, pathologic outcomes, 30-day and 90-day outcomes, and stoma closure rate. Univariable regression analysis was performed to assess risk factors for incomplete TME and anastomotic complications. RESULTS: Between September 2017 and April 2022, 70 males and 30 females with median age of 58 (IQR 49-62) years and BMI 27.8 (IQR 23.9-31.8) kg/m2 underwent 2-team taTME for tumors located a median 5.8 (IQR 4.5-7.0) cm from the AV. Neoadjuvant radiotherapy was completed in 69%. Intersphincteric resection was performed in 36% and all patients were diverted. Intraoperative complications occurred in 8% including 3 organ injuries, 2 abdominal and 1 transanal conversion. The 30-day and 90-day morbidity rates were 49% (Clavien-Dindo (CD) ≥ 3 in 28.6%) and 56% (CD ≥ 3 in 30.4% including 1 mortality), respectively. Anastomotic complications were reported in 18% including 10% diagnosed within 30 days. Higher anastomotic risk was noted among males (p = 0.05). At a median follow-up of 5 (IQR 3.1-7.4) months, 98% of stomas were closed. TME grade was complete or near complete in 90%, with positive margins in 2 cases (3%). Risk factors for incomplete TME were ASA ≥ 3 (p = 0.01), increased time between NRT and surgery (p = 0.03), and higher operative blood loss (p = 0.003). CONCLUSION: When performed at expert centers, 2-team taTME in patients with low rectal tumors is safe with low conversion rates and high stoma closure rate. Mid-term results will further evaluate oncologic and functional outcomes.

Necessary circumferential resection margins to prevent rectal cancer relapse after abdomino-peranal (intersphincteric) resection.

PURPOSE: The purpose of this study was to determine the adequate circumferential resection margin (CRM) for abdomino-peranal (intersphincteric) resection (ISR) that would prevent the relapse of rectal cancers. METHODS: The records of 41 cases that underwent curative ISR for rectal cancer were retrospectively reviewed. The relapse-free survival rates and overall survival rates were evaluated and correlated with the maximum depth of the inner muscularis layer reached during ISR (i.e., the radial margin [RM] and distal margin [DM]). Cases were divided into three groups based on the sizes of the RM and DM: (1) group A (RM >2 mm and DM >1.5 cm), (2) group B (RM >2 mm or DM >1.5 cm but not both), and (3) group C (RM <2 mm and DM <1.5 cm). RESULTS: The relapse-free survival rates of the cases in group C were lower than those in the cases of group A or group B (p = 0.002 and 0.037, respectively). The resection margins required to prevent rectal cancer relapse were >2 mm for the RM and >1.5 cm for the DM. For these margins, the intersphincteric space had to be entered (i.e., between the internal and external anal sphincters). CONCLUSION: It is critical to enter the intersphincteric space to ensure an adequate CRM (RM >2 mm and DM >1.5 cm) for preventing rectal cancer recurrence after ISR.

Radial resection margin distinguishes between superficial versus deep resection in colorectal cancer: a retrospective study.

Randomized studies showed that robotic surgery was short-term useful and safe for cancer patients. We investigated whether robots improve deep resection margins or superficial resection margins for radial resection margins in terms of short-term results. From an institutional database, we selected all superficial groups (≤ 3 mm) and deeper groups (≥ 4 mm) with rectal cancer treated with resection for a year. We evaluated the short-term post-operative 90-day outcomes on a radial resection size-based margin differentiation, including the first bowel movement, length of hospital stay, sepsis, and harvested lymph node. The main results were grades III-IV on the Clavien-Dindo scale and complications. We found 120 patients who had oncologic resection of rectal cancer; 42 patients with a superficial radial resection margin of ≤ 3 mm, all the following outcomes improved: the harvested lymph node, proximal resection margin, TME, flatus time, liquid diet duration, anastomotic leakage, and sepsis. Among these advantages were a reduced risk of metastasis and an overall reduction in local recurrence.

Prognostication and optimal criteria of circumferential margin involvement for esophageal cancer after chemoradiation and esophagectomy.

Purpose: Circumferential radial margin (CRM) involvement by tumor after resection for esophageal cancer has been suggested as a significant prognostic factor. However, the prognostic value of CRM involvement after surgery with neoadjuvant concurrent chemoradiotherapy (CCRT) is unclear. This study aimed to evaluate the prognostic value of and survival outcomes in CRM involvement as defined by the Royal College of Pathologists (RCP) and the College of American Pathologists (CAP) for patients with esophageal cancer undergoing neoadjuvant CCRT and esophagectomy. Methods: A total of 299 patients with esophageal cancer who underwent neoadjuvant CCRT followed by esophagectomy between 2006 and 2016 were enrolled in our study. The CRM status of the specimens obtained was determined pathologically according to both the CAP and RCP criteria. Survival analyses were performed and compared according to the two criteria. Results: Positive CRM was found in 102 (34.1%) and 40 (13.3%) patients according to RCP and CAP criteria, respectively. The overall and progression-free survival rates were significantly lower in the CRM-positive group than in the CRM-negative group according to both the RCP and CAP criteria. However, under multivariate analysis, in addition to pathological T and N staging of the tumor, only CAP-defined CRM positivity was a significant prognostic factor with adjusted hazard ratios of 2.64 (1.56-4.46) and 2.25 (1.34-3.78) for overall and progression-free survival, respectively (P < 0.001). Conclusion: In patients with esophageal cancer undergoing neoadjuvant CRT followed by esophagectomy, CAP-defined CRM positivity is an independent predictor of survival. Adjuvant therapy should be offered to patients with positive CRM.

The Prognostic Role of True Radical Resection in Perihilar Cholangiocarcinoma after Improved Evaluation of Radial Margin Status.

BACKGROUND: The evaluation of surgical margins in resected perihilar cholangiocarcinoma (PHCC) remains a challenging issue. Both ductal (DM) and radial margin (RM) should be considered to define true radical resections (R0). Although DM status is routinely described in pathological reports, RM status is often overlooked. Therefore, the frequency of true R0 and its impact on survival might be biased. OBJECTIVE: To improve the evaluation of RM status and investigate the impact of true R0 on survival. METHODS: From 2014 to 2020, 90 patients underwent curative surgery for PHCC at Verona University Hospital, Verona, Italy. Both DM (proximal and distal biliary margin) and RM (hepatic, periductal, and vascular margin) status were evaluated by expert hepatobiliary pathologists. Patients with lymph-node metastases or positive surgical margins (R1) were candidates for adjuvant treatment. Clinicopathological and survival data were retrieved from an institutional database. RESULTS: True R0 were 46% (41) and overall R1 were 54% (49). RM positivity resulted in being higher than DM positivity (48% versus 27%). Overall survival was better in patients with true R0 than in patients with R1 (median survival time: 53 vs. 28 months; p = 0.016). Likewise, the best recurrence-free survival was observed in R0 compared with R1 (median survival time: 32 vs. 15 months; p = 0.006). Multivariable analysis identified residual disease status as an independent prognostic factor of both OS (p = 0.009, HR = 2.68, 95% CI = 1.27-5.63) and RFS (p = 0.009, HR = 2.14, 95% CI = 1.20-3.83). CONCLUSION: Excellent survival was observed in true R0 patients. The improved evaluation of RM status is mandatory to properly stratify prognosis and select patients for adjuvant treatment.

Minimum radial margin in pelvic exenteration for locally advanced or recurrent rectal cancer.

PURPOSE: The aim of this study was to clarify the suitable radial margin (RM) for favourable outcomes after pelvic exenteration (PE), focusing on the discrepancy between the concepts of circumferential resection margin (CRM) and traditional R status. METHODS: Seventy-three patients with locally advanced (LARC, n = 24) or locally recurrent rectal cancer (LRRC, n = 49) who underwent PE between 2006 and 2018 were retrospectively analysed. Patients were histologically classified into the following 3 groups; wide RM (≥1 mm, n = 45), narrow RM (0-1 mm, n = 10), and exposed RM (n = 18). The analysis was performed not only in the entire cohort but also in each disease group separately. RESULTS: The rates of traditional R0 (RM > 0 mm) and wide RM were 75.3% and 61.6%, respectively, resulting in the discrepancy rate of 13.7% between the two concepts. Preoperative radiotherapy was given in 12.3%. In the entire cohort, the local recurrence and overall survival (OS) rates for narrow RMs were significantly worse than those for wide RMs (p < 0.001 and p = 0.002), but were similar to those for exposed RMs. In both LARC and LRRC, RM < 1 mm resulted in significantly worse local recurrence and OS rates compared to the wide RMs. Multivariate analysis showed that RM < 1 mm was an independent risk factor for local recurrence in both LARC (HR 15.850, p = 0.015) and LRRC (HR 4.874, p = 0.005). CONCLUSIONS: Narrow and exposed RMs had an almost equal impact on local recurrence and poor OS after PE. Preoperative radiotherapy might have a key role to ensure a wide RM.

Comparison of oncological outcomes between low anterior resection and abdominoperineal resection for rectal cancer: A retrospective cohort study using a multicenter database in Japan.

BACKGROUND: It remains controversial whether the abdominoperineal resection (APR) procedure itself has a negative impact on prognosis compared with sphincter-saving surgery (SSS). The purpose of this study was to investigate whether the operation type affects the prognostic outcome in rectal cancer using a multicenter database in Japan. METHODS: The study involved 2533 patients who underwent APR or SSS and were registered in the Japanese Society for Cancer of the Colon and Rectum database, which includes data from 74 centers, between 2003 and 2007. The primary endpoints were overall survival (OS) and relapse-free survival (RFS). The secondary endpoints were local recurrence rate (LRR) and pathological radial margin (pRM) status. RESULTS: Multivariate analysis identified pathological tumor depth, lymph node status, and pRM status to be associated with oncological outcomes (OS, RFS, LRR). Although the oncological outcomes were worse after APR than after SSS in univariate analysis, there was no significant difference in OS (hazard ratio 1.08; 95% confidence interval [CI] 0.85-1.37) or RFS (hazard ratio 1.06; 95% CI 0.87-1.30) between APR and SSS. There was also no significant difference in LRR (odds ratio 1.11, 95% CI 0.70-1.77). Multivariate analysis showed that operation type was associated with positive pRM (odds ratio 3.13, 95% CI 0.18-0.56). CONCLUSIONS: There was no significant difference in oncological outcomes between APR and SSS for rectal cancer. The risk of positive pRM was higher for APR and performing radial margin-negative surgery is an important factor in improving the oncological outcomes of APR.