***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: A total of 798 studies were identified following the initial search. No published or unpublished randomised controlled trials comparing primary tumour resection versus no resection in asymptomatic patients with unresectable stage IV colorectal cancer who were treated with chemo/radiotherapy were identified. Seven non-randomised studies, potentially eligible for inclusion, were identified: 2 case-matched studies, 2 CCTs and 3 retrospective cohort studies. Overall, these trials included 1.086 patients (722 patients treated with primary tumour resection, and 364 patients managed first with chemotherapy and/or radiotherapy). Resection of the primary tumour in asymptomatic patients with unresectable stage IV colorectal cancer who are managed with chemo/radiotherapy is not associated with a consistent improvement in overall survival. In addition, resection does not significantly reduce the risk of complications from the primary tumour (i.e.  obstruction, perforation or bleeding). Yet there is enough doubt with regard to the published literature to justify further clinical trials in this area. The results from an ongoing high quality randomised controlled trial will help to answer this question.
Output:

Some studies have suggested that resecting the primary cancer can prolong survival and prevent complication arising from the cancer, such as obstruction or bleeding. This review addresses the question of whether surgically removing the primary cancer is beneficial to patients with advanced and unresectable colorectal cancer. No randomised controlled trials were identified.