Correlation Between Grade of Clinical Response to Neoadjuvant Therapy for Rectal Cancer and Oncologic Outcomes in the Era of Watch-and-Wait.

Background: The watch-and-wait strategy provides an opportunity to pursue nonoperative management in rectal cancer patients with clinical complete response after neoadjuvant therapy. The management of those with near-complete response remains controversial.

Objective: We assessed the oncologic outcomes of patients managed by watch-and-wait versus total mesorectal excision according to clinical response to neoadjuvant therapy.

Nonoperative management of rectal cancer.

The management of locally advanced rectal cancer has changed drastically in the last few decades due to improved surgical techniques, development of multimodal treatment approaches and the introduction of a watch and wait (WW) strategy. For patients with a complete response to neoadjuvant treatment, WW offers an opportunity to avoid the morbidity associated with total mesorectal excision in favor of organ preservation. Despite growing interest in WW, prospective data on the safety and efficacy of nonoperative management are limited.

Predictors of Recurrence in Nonmetastatic Appendiceal Epithelial Cancers: An Updated Single-Center Experience Over 25 Years.

Background: Appendiceal epithelial tumors are rare and encompass a broad set of adenocarcinoma histologies, including mucinous (mAC), colonic-type (cAC), and goblet cell (GCA) adenocarcinomas. It has previously been reported that nodal disease predicted recurrence in patients with nonmetastatic appendiceal adenocarcinomas, supporting diagnostic laparoscopy with right hemicolectomy for staging and assessment for risk of recurrence. In this update, we sought to identify predictors of nodal disease on initial diagnostic pathology in nonmetastatic adenocarcinomas.

Surgical Site Infections in Simultaneous Colorectal and Liver Resections for Metastatic Colorectal Adenocarcinoma.

Background: Surgical site infections (SSIs) are a major driver of morbidity after combined liver and colorectal surgery for metastatic colorectal cancer. Available literature is inadequate to characterize risk factors and benchmarks for quality improvement.

Methods: Consecutive cases of simultaneous liver and colorectal surgery for colorectal adenocarcinoma from November 2013 through September 2022 were reviewed for SSIs per National Surgical Quality Improvement Program (NSQIP) and National Healthcare Safety Network (NHSN) criteria.

Cost-Effectiveness of Total Neoadjuvant Therapy With Selective Nonoperative Management for Locally Advanced Rectal Cancer: Analysis of Data From the Organ Preservation for Rectal Adenocarcinoma Trial.

Purpose: The clinical efficacy of total neoadjuvant therapy (TNT) followed by selective nonoperative management (NOM) for locally advanced rectal cancer (LARC) was examined in the Organ Preservation for Rectal Adenocarcinoma (OPRA) trial. We investigated the cost and quality-of-life implications of adopting this treatment approach.

Methods: We analyzed clinical, cost, and quality-of-life outcomes for TNT with selective NOM in comparison with chemoradiotherapy (CRT)-surgery-adjuvant chemotherapy (standard of care [SOC]) using data from OPRA, prospective cohorts, and published studies.

Progressive plasticity during colorectal cancer metastasis.

As cancers progress, they become increasingly aggressive-metastatic tumours are less responsive to first-line therapies than primary tumours, they acquire resistance to successive therapies and eventually cause death. Mutations are largely conserved between primary and metastatic tumours from the same patients, suggesting that non-genetic phenotypic plasticity has a major role in cancer progression and therapy resistance. However, we lack an understanding of metastatic cell states and the mechanisms by which they transition.

Deformable Mapping of Rectal Cancer Whole-Mount Histology with Restaging MRI at Voxel Scale: A Feasibility Study.

Purpose To develop a radiology-pathology coregistration method for 1:1 automated spatial mapping between preoperative rectal MRI and ex vivo rectal whole-mount histology (WMH). Materials and Methods This retrospective study included consecutive patients with rectal adenocarcinoma who underwent total neoadjuvant therapy followed by total mesorectal excision with preoperative rectal MRI and WMH from January 2019 to January 2022. A gastrointestinal pathologist and a radiologist established three corresponding levels for each patient at rectal MRI and WMH, subsequently delineating external and internal rectal wall contours and the tumor bed at each level and defining eight point-based landmarks.

Baseline MRI predictors of successful organ preservation in the Organ Preservation in Rectal Adenocarcinoma (OPRA) trial.

Background: Prospective randomized trials have not yet identified baseline features predictive of organ preservation in locally advanced rectal cancers treated with total neoadjuvant therapy and a selective watch-and-wait strategy.

Methods: This was a secondary analysis of the OPRA trial, which randomized patients with stage II-III rectal adenocarcinoma to receive either induction or consolidation total neoadjuvant therapy. Patients were recommended for total mesorectal excision, or watch and wait based on clinical response at 8 ± 4 weeks after completing treatment.

MRI Predicts Residual Disease and Outcomes in Watch-and-Wait Patients with Rectal Cancer.

Background MRI plays a crucial role in restaging locally advanced rectal cancer treated with total neoadjuvant therapy (TNT); however, prospective studies have not evaluated its ability to accurately select patients for nonoperative management. Purpose To evaluate the ability of restaging MRI to predict oncologic outcomes and identify imaging features associated with residual disease (RD) after TNT. Materials and Methods This was a secondary analysis of the Organ Preservation in Rectal Adenocarcinoma (OPRA) trial, which randomized participants from April 2014 to March 2020 with stages II or III rectal adenocarcinoma to undergo either induction or consolidation TNT.

Micro-Computed Tomography Whole-Block Imaging Reveals Origin and Path of Rectal Cancer Tumor Deposits: A Pilot Study.

In colorectal carcinoma (CRC), tumor deposits (TDs) are described as macroscopic/microscopic nests/nodules in the lymph drainage area discontinuous with the primary mass, without identifiable lymph node (LN) tissue, and not confined to vascular or perineural spaces. A TD is categorized as pN1C only when no bona fide LN metastasis exists. However, there has been an ongoing debate on whether TDs should be counted as LNs.

Chemoradiotherapy plus induction or consolidation chemotherapy as total neoadjuvant therapy for locally advanced rectal cancer: Pooled analysis of the CAO/ARO/AIO-12 and the OPRA randomized phase 2 trials.

Background: Total neoadjuvant therapy (TNT) has been used for patients with locally advanced rectal cancer. The optimal sequence of chemoradiotherapy (CRT) and chemotherapy (CT) is a matter of debate.

Methods: We performed a pooled analysis of the CAO/ARO/AIO-12 and OPRA multicenter, randomized phase 2 trials to identify patient subsets that could benefit from one TNT sequence over the other regarding disease-free survival (DFS).

Clinical Calculator for Predicting Freedom From Recurrence After Resection of Stage I-III Colon Cancer in Patients With Microsatellite Instability.

Purpose: Outcome for patients with nonmetastatic, microsatellite instability (MSI) colon cancer is favorable: however, high-risk cohorts exist. This study was aimed at developing and validating a nomogram model to predict freedom from recurrence (FFR) for patients with resected MSI colon cancer.

Patients And Methods: Data from patients who underwent curative resection of stage I, II, or III MSI colon cancer in 2014-2021 (model training cohort, 384 patients, 33 events; median follow-up, 38.

Prognostic value of lateral lymph node metastasis in pretreatment MRI for rectal cancer in patients undergoing neoadjuvant chemoradiation followed by surgical resection without lateral lymph node dissection: A systemic review and meta-analysis.

Purpose: To systematically review and meta-analyze the prognostic significance of lateral lymph node metastasis (LLNM) on pretreatment MRI in patients with rectal cancer who undergo neoadjuvant chemoradiation followed by curative surgical resection without lateral lymph node dissection (LLND).

Methods: We searched the MEDLINE and EMBASE databases until September 27, 2023, utilizing the following search terms: (rectal OR rectum OR colorectal) AND (lateral OR sidewall) AND (lymph OR node). The QUIPS tool was employed to evaluate methodological quality.