Evaluation of national surgical practice for lateral lymph nodes in rectal cancer in an untrained setting

Background. Involved lateral lymph nodes (LLNs) have been associated with increased local recurrence (LR) and ipsi-lateral LR (LLR) rates. However, consensus regarding the indication and type of surgical treatment for suspicious LLNs is lacking. This study evaluated the surgical treatment of LLNs in an untrained setting at a national level.Methods. Patients who underwent additional LLN surgery were selected from a national cross-sectional cohort study regarding patients undergoing rectal cancer surgery in 69 Dutch hospitals in 2016. LLN surgery consisted of either 'node-picking' (the removal of an individual LLN) or 'partial regional node dissection' (PRND; an incomplete resection of the LLN area). For all patients with primarily enlarged (=7 mm) LLNs, those undergoing rectal surgery with an additional LLN procedure were compared to those undergoing only rectal resection.Results. Out of 3057 patients, 64 underwent additional LLN surgery, with 4-year LR and LLR rates of 26% and 15%, respectively. Forty-eight patients (75%) had enlarged LLNs, with corresponding recurrence rates of 26% and 19%, respectively. Node-picking (n = 40) resulted in a 20% 4-year LLR, and a 14% LLR after PRND (n = 8; p = 0.677). Multivariable analysis of 158 patients with enlarged LLNs undergoing additional LLN surgery (n = 48) or rectal resection alone (n = 110) showed no significant association of LLN surgery with 4-year LR or LLR, but suggested higher recurrence risks after LLN surgery (LR: hazard ratio [HR] 1.5, 95% confidence interval [CI] 0.7-3.2, p = 0.264; LLR: HR 1.9, 95% CI 0.2-2.5, p = 0.874).Conclusion. Evaluation of Dutch practice in 2016 revealed that approximately one-third of patients with primarily enlarged LLNs underwent surgical treatment, mostly consisting of node-picking. Recurrence rates were not significantly affected by LLN surgery, but did suggest worse outcomes. Outcomes of LLN surgery after adequate training requires further research

Absence of tumor invasion into pelvic structures in locally recurrent rectal cancer: prediction with preoperative MR imaging

PURPOSE: To retrospectively assess the accuracy of preoperative magnetic resonance (MR) imaging for identification of tumor invasion into pelvic structures in patients with locally recurrent rectal cancer scheduled to undergo curative resection. MATERIALS AND METHODS: The institutional review board approved this study, and informed consent was waived because of the retrospective nature of the study. Preoperative MR images in 40 consecutive patients with locally recurrent rectal cancer scheduled to undergo curative treatment between October 2003 and November 2006 were analyzed retrospectively. Four observers with different levels of experience in reading pelvic MR images assessed tumor invasion into the following structures: bladder, uterus or seminal vesicles, vagina or prostate, left and right pelvic walls, and sacrum. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated, and a receiver operating characteristic curve was constructed. Surgical and/or histopathologic findings were used as the reference standard. Interobserver agreement was measured by using kappa statistics. RESULTS: Preoperative MR imaging was accurate for the prediction of tumor invasion into structures with negative predictive values of 93%-100% and areas under receiver operating characteristic curves of 0.79-1.00 for all structures and observers. Positive predictive values were 53%-100%. Disease was overstaged in 11 (observer 1), 22 (observer 2), 10 (observer 3), and nine (observer 4) structures and was understaged in nine (observer 3) and two (observer 4) structures. Assessment failures were mainly because of misinterpretation of diffuse fibrosis, especially at the pelvic side walls. Interobserver agreement ranged between 0.64 and 0.99 for experienced observers. CONCLUSION: Preoperative MR imaging is accurate for the prediction of absence of tumor invasion into pelvic structures. MR imaging may be useful as a preoperative road map for surgical procedure and may thus increase chances of complete resection. Interpretation of diffuse fibrosis remains difficult

Prognostic Implications of MRI-Detected EMVI and Tumor Deposits and Their Response to Neoadjuvant Therapy in cT3 and cT4 Rectal Cancer

Purpose: Magnetic resonance imaging-detected extramural venous invasion (mrEMVI) and tumor deposits (TDs) are risk factors for the development of local recurrence and distant metastases (DMs) in rectal cancer. However, little is known about their response to neoadjuvant treatment and its relation to oncologic outcomes. This study evaluated the incidence and features of mrEMVI and TDs before and after neoadjuvant treatment in relation to the development of local recurrence and DMs.Methods and Materials: Patients with cT3/4 rectal cancer without synchronous metastases who underwent surgery in a tertiary referral hospital were retrospectively analyzed. MRI scans were re-evaluated for the presence of mrEMVI, the occurrence of TDs, and response to neoadjuvant therapy (mr-vTRG).Results: In total, 277 patients were included, of whom 163 (58.8%) presented with mrEMVI. TDs were present in 56.4% of mrEMVI-positive and 9.6% of mrEMVI-negative patients (P < .001). The 5-year DM rate was significantly higher in mrEMVI-positive patients with and without TDs (45.2% and 35.9%, respectively) compared with mrEMVI-negative patients (25.7%; P = .012). After neoadjuvant treatment, the 5-year DM rate of patients with mr-vTRG 3-5 was 46.1%, whereas good responders (mr-vTRG 1-2) had a DM rate similar to mrEMVI-negative patients (25.7% and 25.7%, respectively; P = .002). The occurrence of TDs and larger mrEMVI size resulted in a lower likelihood of regression of mrEMVI.Conclusions: The prevalence of mrEMVI and TDs in cT3-4 rectal cancer is high and is associated with worsened oncologic outcomes. mrEMVI regression (mr-vTRG 1-2), which occured in 25% of the cases, leads to oncologic outcomes similar to those in patients without mrEMVI on baseline MRI. (C) 2021 The Author(s). Published by Elsevier Inc