Inguinal hernia has an estimated prevalence of 4% in adults > 45 years. Strangulated hernias account for 10% of cases^1,2.

The combination of colorectal cancer and inguinal hernia is uncommon with an estimated incidence of 0.5% in the excised sac. Most cases are found intraoperatively in patients undergoing emergency surgery for strangulated hernia using an open approach. In these patients the differential diagnosis must be made with intrasaccular perforated malignant tumors^1,2.

Tumors found in hernia sacs include saccular tumors when they involve the hernia sac, primitive or metastatic intrasaccular tumors when they affect the organ or structures organized in the sac, and extrasaccular tumors. Left-sided colon cancer is the most common primitive intrasaccular tumor^1,2.

Laparoscopic surgery has been reported as an exceptional approach in patients who were diagnosed with colon cancer in the preoperative period of a scheduled surgery for inguinal hernia^1,2.

A 60-year-old male patient with a history of hypertension was undergoing preoperative evaluation of an irreducible left inguinoscrotal hernia lasting 10 years. Bowel motility was normal. The fecal occult blood test was positive. The colonoscopy revealed a vegetative and obstructive lesion in the hernia sac involving all the circumference of the sigmoid colon. The pathology examination confirmed the diagnosis of adenocarcinoma. A preoperative staging computed tomography scan was performed. The lesion mentioned above appeared at the level of the sigmoid colon and was contained in an indirect left inguinoscrotal hernia. There were no elements of systemic dissemination (Fig. 1). A median laparotomy was initially performed, but it as was impossible to reduce the sigmoid loop through this approach an oblique left inguinal incision was made. Once the hernia was reduced (Fig. 2), the next step was sigmoidectomy and oncologic mesocolic excision. Bowel continuity was restored with end-to-end double-stapled colorectal anastomosis using a circular 202 stapler (31-mm end-to-end anastomosis stapler) via the transanal route. The inguinal hernia was repaired with the Lichtenstein technique using a polypropylene mesh. The postoperative period was uneventful, and the patient was discharged on postoperative day 7. The pathology examination of the surgical specimen reported a well-differentiated adenocarcinoma, pT3N0M0, stage IIA. Adjuvant therapy was not necessary.

Figure 1 Sigmoid colon tumor in a left inguinal hernia 

Figure 2 Intraoperative image. Sigmoid colon tumor in a left inguinal hernia. 

Less than 1 of 200 cases of colorectal cancer are localized in an inguinal hernia³.

The literature review shows that most of them are found in the sigmoid colon, in a left inguinal hernia and are most common elderly male patients, as in this report^1,3. A literature search of the 1900-2011 PubMed database, entering ‘‘colon carcinoma’’ and ‘‘inguinal hernia’’ as key words, identified 31 cases of colon carcinoma in an inguinal hernia, mostly in elderly men. Sigmoid colon carcinomas were found in 25 cases, with cancer of the cecum in 4, cancer of the ascending colon in 1, and cancer of the transverse colon in 1 case. Colon cancer in an inguinal sac is often difficult to diagnose and 45% of cases (n = 14) in the series reported were not diagnosed preoperatively. Emergency operations were performed for obstruction or perforation in 17 (55 %) patients².

Some recent publications have reported 38 cases in the literature¹. The tactical aspects for the combined treatment of both conditions and the surgical approach are a relevant issue for the management of these patients. It seems reasonable that in operable patients without elements of incurable disease curative criteria should be implemented, resecting the tumor in the involved colonic sector with oncologic margins and performing the corresponding mesocolic excision. Timing of bowel reconstruction will depend on the context and timing of colectomy; primary gastrointestinal anastomosis is feasible in the absence of infection, considering patient’s status and the risk of suture failure. In most cases, surgery is performed on an emergency basis and in these cases colon cancer is an incidental finding, which usually results in suboptimal oncologic treatment¹. The approach (either through laparoscopy or laparotomy) and the best incision vary in the different registries. Laparotomy has been reported in patients undergoing emergency surgery for strangulated hernia. An additional incision is frequently necessary to perform the resection. In these cases, a midline incision is usually necessary in addition to the inguinal incision to complete mesocolic excision, thus increasing morbidity and mortality. Therefore, it is clear that the preoperative diagnosis is essential to plan the approach.

Some authors suggest that colectomy and wall repair can be performed in the same procedure using a transverse incision in the left iliac fossa or inguinal fossa. The laparoscopic approach is an exception in the reports, even more in complicated hernias². Wall repair with mesh placement in uncommon as most surgeries are contaminated due to the emergency basis^1,2.

Despite our patient underwent a scheduled surgery, the laparotomy approach through a midline incision was considered due to the tumor size, but as it was impossible to reduce the sigmoid loop with the tumor, a subsequent inguinal approach was necessary. As the inguinal access was not contaminated, we decided to perform an inguinal hernia repair with placement of a polypropylene mesh.

Gnás et al. reported a case of left-sided colon cancer in an inguinoscrotal hernia as an intraoperative finding in a 63-year-old patient scheduled for elective left inguinal hernia repair. Th tumor infiltrated the elements of the left spermatic cordon and both structures were excised in one block. An initial inguinal incision was performed but a midline laparotomy was necessary to complete sigmoid colon resection with hand-sewn end-to-end anastomosis. The resection was non-oncologic due to multiple liver metastases as a concomitant finding. The authors concluded that ultrasound could be useful for the preoperative evaluation of these patients, as these intraoperative findings are often unsuspected⁴.

In this patient, although we do not routinely indicate computed tomography scan in the preoperative assessment of an isolated inguinoscrotal hernia, we indicated computed tomography scan of the abdomen and pelvis complete the preoperative staging of a tumor incidentally found by colonoscopy. Salemans et al. described the case of a 93-yearold male patient admitted to the emergency department due to rectal bleeding and a non-tender irreducible mass in the left groin. The patient underwent computed tomography scan and colonoscopy. A diagnosis of sigmoid colon adenocarcinoma was made. Surgery was performed through a single oblique inguinal approach to reduce risks and mortality. The sigmoid colon was resected with primary colorectal anastomosis. The inguinal hernia was repaired and a mesh was placed during the same procedure. The procedure was not considered optimal from an oncological point of view as 9 lymph nodes were resected³.

There is no evidence supporting one approach over the other for colon cancer in an inguinal hernia. Deciding between the abdominal or inguinal approach will depend on diagnostic and surgical timing, intraoperative findings, patient’s anatomy, and surgeon’s experience, among other factors⁵.

Some clinical features as anemia, long-standing inguinal hernia, irreducible inguinal mass or weight loss should raise suspicion of a concomitant diagnosis of malignancy in an inguinal hernia^1,2.

In conclusion, the concomitant finding of a colon tumor in an inguinal hernia is rare; it is usually an intraoperative finding of a complicated inguinal hernia. A thorough physical examination in patients undergoing preoperative evaluation for inguinal hernia and high level of suspicion based on clinical findings suggest the need for additional imaging tests and endoscopic procedures, which are essential to make a preoperative diagnosis and to plan surgery.