Novel emergency management of descending colon cancer presenting with retroperitoneal perforation.

Sir,

Retroperitoneal perforations of descending colon cancer (CCA) are exceedingly rare. Only one report of a flank abscess resulting from retroperitoneal perforation of descending CCA exists in the literature.[1] Ours appears to be the first United States' patient reported with this presentation. We describe our novel emergency management approach that ensured an excellent outcome for this patient.

A 44-year-old male patient presented with 3 weeks of left flank swelling, fevers and weight loss. He was tachycardic and hypotensive. Examination revealed rebound tenderness in the left lower quadrant and an erythematous fluctuant left flank mass. Laboratory investigation revealed leukocytosis to 39.4 × 103/μL (normal <11 × 103) and hemoglobin 4.6 g/dL (normal >13.5). Computed tomography demonstrated a particulate 15.4 cm left retroperitoneal collection communicating with the descending colon through a focal perforation [Figure 1].

Figure 1

(a and b) Axial and sagittal sections of abdominal computed tomography scan showing large feculent left retroperitoneal collection communicating with an abnormally thickened segment of the descending colon via a focal perforation (white arrow)

After resuscitation and initiation of broad-spectrum antibiotics, an exploratory laparotomy was performed. A markedly inflamed segment in the mid-descending colon adherent to the retroperitoneum was mobilized, revealing a focal perforation. A left hemicolectomy was performed. The feculent retroperitoneum required wide debridement [Figure 2a]. We elected to leave the patient in colonic discontinuity and a temporary vacuum-assisted abdominal closure was performed. The patient was then turned to the right lateral decubitus position and external debridement of this collection was performed via an S-shaped counter-incision [Figure 2b]. The following day, an end transverse colostomy was performed, the left retroperitoneal defect sealed with a pedicled omental flap [Figure 2c] and the abdominal fascia closed. A vacuum-assisted closure device was employed to manage the left flank incision. Eventually, this incision was closed utilizing a myocutaneous advancement flap. Pathologic analysis revealed a margin-negative 2.8 cm adenocarcinoma with peritoneal invasion, but without nodal involvement (T4bN0M0). Having completed adjuvant chemotherapy with fluorouracil and oxaliplatin (FOLFOX), he remains disease-free 12 months after surgery.

Figure 2

(a) Left retroperitoneal defect (arrow) after operative debridement of feculent retroperitoneal abscess. (b) S-shaped counter-incision in the left flank through, which an external debridement of the left retroperitoneum was performed. (c) Use of an omental patch (broken lines) to cover the left retroperitoneal defect during the second-look laparotomy

Despite well-established screening guidelines in the United States, up to 15-20% of CCA presents as obstruction and/or perforation. The incidence of perforated CCA is 2-9.6% in various series, and occurs either due to full-thickness necrosis at the tumor site or diastatic “blow-out” between an obstructing tumor and a competent ileocecal valve.[2] Perforated CCA is associated with higher perioperative mortality, local recurrence and peritoneal carcinomatosis although overall survival is similar to non-perforated cases after adjusting for perioperative mortality.[3] This suggests that the perioperative septic insult rather than tumor dissemination is more contributory to the worse prognosis with perforation. Although contained perforations have improved outcomes compared with free perforations, they present insidiously, pose diagnostic challenges and lead to interventional delays. Conceivably, inflammatory responses to bacterial contamination in extraperitoneal tissues are less exuberant than in the peritoneal cavity, causing non-specific symptoms that are not recognized immediately.[4]

For perforated descending colonic pathology, a Hartmann's procedure is recommended. If the diagnosis of CCA can be made pre-operatively, an oncologically appropriate operation should be attempted. Regardless of nodal status, adjuvant chemotherapy is recommended for locally advanced CCA.[5]

Although infectious causes are responsible for a majority of retroperitoneal abscesses in the developing world, bowel-related pathology — inflammatory bowel disease, diverticulitis, appendicitis, etc., — more commonly accounts for such abscesses in the italicize world. In the appropriate clinical setting, a flank abscess should also alert the astute clinician of retroperitoneal perforation from colonic malignancy.