Synchronous tumor deposits and short circumferential resection margin predict poor outcomes in rectal cancer: a retrospective cohort study
Simon Horak Pedersen, Simon Lundström, Pamela BuchwaldAbstract
Introduction
Tumor deposits (TDs) and short circumferential resection margin between 0.1–1 mm (CRM+) are known negative prognostic factors in rectal cancer. Despite proven individual prognostic value, the presence and impact of synchronous involvement has not been studied. The aim of this study was therefore to investigate the prognostic impact of synchronous involvement of TDs and CRM+.
Methods
Patients that underwent surgery for rectal cancer during 2011–2014 and 2016–2019 were identified and extracted from the Swedish Colorectal Cancer Registry. Patients were stratified based on TD(+/−) and CRM(+/−). TD+ and CRM+ effect on overall survival (OS) and distant metastasis (DM) were investigated using uni- and multivariable Cox-regression and presented as HR (95% c.i.). Multivariable cox-regression analysis was adjusted for age, sex, neoadjuvant therapy, and number of positive lymph nodes.
Results
Of 14 920 eligible patients, 8832 were included in the final analysis. CRM+ was more common for TD+ tumors compared to TD- (14.0 versus 4.0%, P < 0.001). In the multivariable analysis, synchronous TD+CRM+ involvement was associated with lower OS (HR 2.7, 95% c.i. 2.1–3.4), and higher risk of DM (HR 4.1, 95% c.i. 3.2–5.2) compared with both TD+CRM− (OS HR 1.9, 95% c.i. 1.7–2.1; DM HR 2.8, 95% c.i. 2.5–3.2), and TD−CRM+ (OS HR 1.5, 95% c.i. 1.3–1.9; DM HR 1.8, 95% c.i. 1.4–2.3).
Discussion
TD+ is significantly associated with CRM+, and synchronous TD+ and CRM+ are negative prognostic factors beyond isolated TD+ and CRM+ for OS and DM. Further consideration of CRM may be warranted in TD+ rectal cancers.