Anal cancer treatment may lead to colostomy
MedWire News: The need for colostomy in patients who undergo radiotherapy for anal cancer appears to be related, in a third of cases, to their treatment, study findings suggest.
Anal cancer patients who underwent local excision before tumor-directed radiotherapy were more than four times as likely to need a colostomy due to treatment as patients who did not have local excision, the researchers report in the Journal of Clinical Oncology.
Meanwhile, independent research suggests that local excision of small, anal tumours before administration of radiotherapy may not protect against local failure.
Kåre Sunesen (Aarhus University Hospital, Denmark) and colleagues explored cause-specific colostomy rates after radiotherapy in 235 patients.
The researchers reviewed national registries and medical records for anal cancer patients diagnosed between 1995 and 2003 who underwent radiotherapy or chemotherapy with intention to cure, in four centers in Denmark.
Incidence rates of colostomy related to the tumor and that related to the treatment until 2008 were then calculated.
Over 5 years, colostomy related to the tumor was performed in 26% of patients, among whom patients with tumors greater than 6 cm in size were almost four times more likely to need a colostomy than patients with smaller tumors after adjusting for confounding factors such age, gender, tumor size and nodal status (adjusted hazard ratio=3.8)..
In contrast, the 5-year cumulative incidence of colostomy related to therapy was 8%. However, patients who underwent local excision before radiotherapy were 4.5 times more likely to require therapy-related colostomy than those who did not have local excision.
Sunesen et al comment: "Taken together, these findings suggest that a local excision should not be the primary therapeutic option, even for small tumors."
Although most patients required colostomy 2-5 years after radiotherapy, 9% of patients underwent colostomy before treatment due to vaginal involvement, anorectal abscess or other conditions. None of these patients became from colostomy.
The researchers therefore conclude: "Patients should be informed that a pretreatment colostomy is usually permanent."
By Josephine McCoan