Perforated colonic neoplasms with retroperitoneal abscess and fistula formation involving the abdominal wall are extremely rare. They are confronting diagnostic challenges for the unsuspecting clinician and often fatal in the absence of early identification and management. Patients are septic on presentation requiring aggressive resuscitation, intravenous antimicrobial therapy and prompt surgical intervention for sepsis control. Colonic perforations are predominately intraperitoneal occurring proximal to the tumour with subsequent peritonitis. Retroperitoneal perforations are less common and can be associated with a psoas abscess and fistula formation involving the thigh, groin and abdominal wall. A CT scan of the abdomen and pelvis should be considered for septic patients with necrotising soft tissue infections. Gas-fluid collections associated with a perforated colonic neoplasm require urgent damage control surgery. Damage control is preferable for severely septic patients with hostile abdominal compartments not amenable to colonic anastomosis. Post-operative adjuvant chemotherapy is useful in improving survivability in advanced T4 colonic cancers. National colon cancer screening has undoubtedly reduced the likelihood of detecting large T4 colonic tumours. Advanced cancers with malignant colonic perforations are more likely to be seen in high risk population subgroups including people from non-English speaking backgrounds, poor access to healthcare services and those with poor health literacy. Enhanced screening and service delivery minimises unwanted serious clinical catastrophes.
This interesting and unique presentation highlights the clinical challenges of septic patients presenting with an unusual and extremely rare cause of necrotising fasciitis secondary to malignant colonic perforations. The presentation outlines the importance of prompt identification of high risk patients, early imaging and definitive oncological and sepsis control.