Characteristics of Early-Onset vs Late-Onset Colorectal Cancer
REACCT Collaborative, Alexandra Zaborowski, Ahmed Abdile, Michel Adamina, Felix Aigner, Laura d’Allens, Caterina Allmer, Andrea Álvarez, Rocío Anula, Mihailo Andric, S. Atallah, Simon P. Bach, Miklosh Bala, Marie Barussaud, Augustinas Baušys, Brendan Bebington, Andrew D. Beggs, Felipe Bellolio, Melissa-Rose Bennett, Anton Berdinskikh, Vicki Bevan, Sebastiano Biondo, Gabriele Bislenghi, Marc Bludau, Adam Boutall, Nelleke P.M. Brouwer, Carl J. Brown, Christiane J. Bruns, Daniel D. Buchanan, Pamela Buchwald, Jacobus W. A. Burger, Никита Бурлов, Michela Campanelli, Maylis Capdepont, Michele Carvello, Hwee-Hoon Chew, Dimitri Christoforidis, David A. Clark, Marta Climent, Kyle G. Cologne, Tomás Contreras, Roland S. Croner, I. R. Daniels, Giovanni Dapri, Justin Davies, Paolo Delrio, Quentin Denost, Michael Deutsch, André Roncon Dias, André D’Hoore, E. S. Drozdov, Daniel Duek, Malcolm G. Dunlop, Adam Dziki, Aleksandra Edmundson, Sergey Efetov, Alaa El‐Hussuna, Brodie Elliot, Sameh Hany Emile, Eloy Espín, M. D. Evans, Seraina Faes, Omar Faiz, Fergal J. Fleming, Caterina Foppa, G Fowler, Matteo Frasson, Nuno Figueiredo, Tim Forgan, Frank Frizelle, Shamil Gadaev, José Gellona, Tamara Glyn, Jianping Gong, Goran Barisic, Emma Greenwood, Marianne G. Guren, Stephanie Guillon, Ida Gutlic, Dieter Hahnloser, Heather Hampel, Ann Hanly, Hirotoshi Hasegawa, Lene Hjerrild Iversen, Andrew Hill, James Hill, Jiří Hoch, Michael Hoffmeister, Roel Hompes, Luis Hurtado‐Pardo, Fabiano Iaquinandi, Ugnė Imbrasaitė, Rumana Islam, Mehrenah Dorna Jafari, Yukihide Kanemitsu, А. М. Карачун, Ahmer Karimuddin, Deborah S. Keller, Justin Kelly, Rory Kennelly
Abstract
Importance: The incidence of early-onset colorectal cancer (younger than 50 years) is rising globally, the reasons for which are unclear. It appears to represent a unique disease process with different clinical, pathological, and molecular characteristics compared with late-onset colorectal cancer. Data on oncological outcomes are limited, and sensitivity to conventional neoadjuvant and adjuvant therapy regimens appear to be unknown. The purpose of this review is to summarize the available literature on early-onset colorectal cancer. Observations: Within the next decade, it is estimated that 1 in 10 colon cancers and 1 in 4 rectal cancers will be diagnosed in adults younger than 50 years. Potential risk factors include a Westernized diet, obesity, antibiotic usage, and alterations in the gut microbiome. Although genetic predisposition plays a role, most cases are sporadic. The full spectrum of germline and somatic sequence variations implicated remains unknown. Younger patients typically present with descending colonic or rectal cancer, advanced disease stage, and unfavorable histopathological features. Despite being more likely to receive neoadjuvant and adjuvant therapy, patients with early-onset disease demonstrate comparable oncological outcomes with their older counterparts. Conclusions and Relevance: The clinicopathological features, underlying molecular profiles, and drivers of early-onset colorectal cancer differ from those of late-onset disease. Standardized, age-specific preventive, screening, diagnostic, and therapeutic strategies are required to optimize outcomes.