Carcinomatous perforation of the sigmoid colon presenting as a thigh mass.

We report a patient presenting with a left psoas abscess causing necrotizing fasciitis of the upper thigh. The patient underwent exploration of the left thigh through a medial approach, confirming necrotizing fasciitis of the adductor compartment and the femoral triangle. The infective process also involved the left psoas. This was explored retroperitoneally through a left pararectal laparotomy incision. Further exploration revealed a carcinomatous ulcer of the sigmoid colon. Despite active resuscitation, antibiotic therapy, and further debridement, the patient died three days after admission.