Colonic Resection, Stoma, or Self-expanding Metal Stents for Obstructive Left Colon Cancer: the CROSCO-1 study protocol

Background: Colorectal cancer (CRC) is one of the most common cancers worldwide. There are several causes of a mechanical left bowel obstructive but CRC accounts for approximately 50% of cases and in 10-30% of whom it is the presenting syndrome. In most cases, the left colon is involved. At present, the range of therapeutic alternatives in the management of obstructive left CRC in emergency conditions (primary resection vs staged resection with applied self-expanding metallic stents) is broad, whereas internationally validated clinical recommendations in each condition are still lacking. This enormous variability affects the scientific evidence on both the immediate and long-term surgical and oncological outcomes. Methods: CROSCO-1 (Colonic Resection, Stoma or Self-expanding Metal Stents for Obstructive Left Colon Cancer) study is a national, multi-center, prospective observational study intending to compare the clinical results of all these therapeutic regimens in a cohort of patients treated for obstructive left-sided CRC. Results: The primary aim of the CROSCO-1 study is the 1-year stoma rate of patients undergoing primary emergency surgical resection (Hartmann procedure or primary resection and anastomosis) compared with patients undergoing staged resection. Secondary outcomes are 30-day and 90-day major morbidity and mortality, 1-year quality of life and the timing of chemotherapy initiation in the two groups. Future CROSCO studies will follow in which, instead, we will evaluate the long-term oncological outcomes of the two treatment strategies. Conclusions: The results of a large prospective cohort study which will analyze what really happens in the common clinical practice of managing patients with obstructive left CRC will have the aim of understanding which is the best strategy in terms of surgical and oncological outcomes. Indeed, the CROSCO-1 study will analyze the early surgical outcomes for patients with obstructed left CRC. Future CROSCO studies will follow in which, instead, we will evaluate the long-term oncological outcomes of the two treatment strategies.