Malignant Small Bowel Obstruction from Hernia Mesh Invasion by Jejunal Adenocarcinoma: A Report of a Rare Case

Introduction

In the United States, 340 100 patients were admitted to hospitals for small bowel obstruction (SBO) in 2019, with approximately 30 000 of these cases resulting in mortality [1,2]. The estimated healthcare expenditure for SBO treatment in 2019 was a staggering $4.1 billion dollars, with an average length of stay reported as 5 days, reflecting the significant burden this condition imposes on the healthcare system [1]. SBOs are characterized by complete or incomplete blockages of the small intestine, resulting in symptoms such as nausea, bilious emesis, abdominal distention, pain, and obstipation in cases of complete blockage [3]. A variety of factors can contribute to SBOs, including adhesions from previous abdominal or pelvic surgeries (the leading cause in the United States), hernias (the leading cause worldwide), neoplasms, inflammatory bowel disease, and other less common etiologies [2,4]. Management of SBOs hinges on the patient’s symptoms, clinical condition, and cause of the SBO. Non-operative management includes bowel rest, nasogastric tube decompression, and electrolyte replacement. Operative management involves correcting or removing the offending pathology in hopes of restoring normal bowel function [4]. Studies have indicated that approximately 18% of SBO cases ultimately require surgical intervention [5]. Surgical approaches vary from exploratory laparotomy to minimally invasive techniques based on various patient and surgeon factors (beyond the scope of this case report). This case report highlights an unusual and potentially novel cause of a SBO, small bowel malignancy at the site of a prior hernia repair.

Case Report

A man over 89 years old presented with right lower-quadrant abdominal pain, distention, and emesis. Institutional Review Board (IRB) approval was sought, but the IRB felt no approval was needed as long as personal health information (PHI) was not disclosed, and any age over 89 is considered PHI. His medical and surgical histories were significant for bilateral inguinal hernia repair with mesh (date unknown), prostate cancer with radiation treatment in 2017, right hip hemiarthroplasty with intraoperative cardiac arrest 2021, diabetes mellitus type 2, chronic kidney disease stage 2, and hypertension. There was no family history of cancer. Of note, the patient lived at home with his partner, had strong family support, and could independently complete tasks of daily living. At initial presentation, he was hemodynamically stable, afebrile, and had a normal white blood cell (WBC) count. Computed topography (CT) findings were consistent with developing low-grade SBO and possible transition point proximal to the recurrent right inguinal hernia, wall thickening of the ascending colon representing possible neoplasm, and a recurrent left inguinal hernia containing the sigmoid colon, without evidence of obstruction. He was initially managed non-operatively and after 1 day had several bowel movements and improvement in symptoms. General surgery and gastroenterology teams recommended further evaluation with colonoscopy given his age, lack of previous colonoscopy, and imaging findings. The patient denied further workup given his age and resolution of symptoms. Since the patient had resolution of symptoms, ability to tolerate oral intake, and return to base line functional status, he was discharged on day 3 of admission.

The patient presented again 7 days after discharge with similar symptoms of abdominal pain, distention, and emesis. On physical exam he was described as ill-appearing, with diffuse abdominal pain to palpation, fever (38.5°C), and tachycardia (~110 bpm). Laboratory testing demonstrated a WBC count of 20.9. The CT scan at his second admission showed new evidence that the previous SBO site had evolved into a high-grade SBO, with clear transition pointed noted in the right inguinal canal, along with worsening inflammation in the ascending colon. Since he had an artificial right hip, there was significant artifact burden present in the right pelvis and inguinal canal, limiting interpretation (Figures 1–3). We explained to the patient and family the extent of disease, concern for malignancy given the CT findings, and significant risk associated with surgery, especially in an elderly person. Despite the significant risks, the patient and family wanted all available surgical options pursued, so he was taken to the operating room for an exploratory laparotomy with potential bowel resection.

During the exploration, the mid-jejunum was noted to be adhered into the right lower quadrant of the peritoneum and, upon further dissection, it was noted the source of adherence was mesh that had eroded into the peritoneum from a prior herniorrhaphy. The portion of the small bowel adhered to the mesh was resected, containing part of the mesh, an anastomosis was created, and the rest of the mesh was sharply dissected from the peritoneum. Given the prior CT findings concerning for ascending colon neoplasm, lack of colonoscopy history, and low likelihood of surviving a second operation, the decision was made to perform a right hemicolectomy. A side-to-side functional end-to-end ileocolonic anastomosis was created. Both specimens were sent to pathology. He progressed appropriately and was discharged on postoperative day 11 to inpatient rehabilitation.

The pathology report demonstrated the small bowel specimen contained well-differentiated adenocarcinoma with invasion though the full thickness of the muscularis propria and serosal surface and into the fibrous adhesions containing the intraperitoneal mesh. Additionally, the ascending colon had 2 separate foci of adenocarcinoma; one moderately differentiated and one poorly differentiated. We found 8 separate tubular adenomas with high-grade dysplasia and metastases adenocarcinoma involving 2 of 21 lymph nodes, with negative margins. The patient had meet separately with the gastrointestinal and oncology teams to discuss further workup and treatment, ultimately deciding not to pursue any intervention, given his age and the potential adverse effects of treatment.

Discussion

We present a novel finding of adenocarcinoma of the small bowel invading mesh from a previous hernia repair causing a small bowel obstruction. No matter how a hernia is repaired, there are always risks of complication, but malignancy is not mentioned as a complication [6]. A literature search resulted in 2 case reports of squamous cell carcinoma (SCC) discovered in hernia mesh, the causes of the SCC was attributed to chronic non-healing skin ulcers over the surgical site [7,8]. There are additional case reports in which various small bowel or colon cancers were discovered in the hernia defect during repair [9–12]. It has been posited that surgical mesh can be a “non-genotoxic carcinogen” and can lead to neoplasms, but this has never been observed humans [13]. Several large studies, literature reviews, and retrospective reviews all concluded that there is no link between the mesh used in hernia repairs and malignancy [13–15].

Given the patient’s history of pelvic radiation, it may be considered a factor in the development of gastrointestinal malignancy. Pelvic radiation is commonly used in the multitherapy treatment of prostate cancer. Pelvic radiation, like many medical interventions, has associated risks for pelvic radiation syndrome (PRD) and secondary malignancy [16,17]. The intestinal epithelial cells are highly susceptible to damage from radiation, in part due to their short life span of 3–5 days [16,18]. Several recent articles have demonstrated the growing yet controversial link between pelvic radiation and radiation-associated rectal cancer [19,20]. Small bowel adenocarcinomas have been estimated to represent 4% of gastrointestinal malignancies, with jejunal cases comprising 1/3 of these [21]. Surgical treatment of this small bowel obstruction revealed a novel case of jejunal adenocarcinoma invading hernia mesh. The patient’s previous inguinal hernia repair likely resulted in adhesions, which, coupled with radiation exposure, may have led to malignancy.

Conclusions

Small bowel obstructions affect a large portion of the population and result in significant health care expenses. The management of SBOs is multifaceted, and identifying the etiology is vital for treatment, especially in operative cases. While there are many causes of SBOs, this case shows an exceedingly rare and potentially novel case of jejunal adenocarcinoma that invaded into hernia mesh. While there is not a clear explanation behind this patients’ pathology, we hypothesize that his prior hernia surgery led to an intra-abdominal adhesion, and subsequent pelvic radiation may have facilitated the malignancy, which invaded the mesh and caused a high-grade small bowel obstruction. Future research via case series or observational studies to determine if there is a correlation between hernia mesh exposed to pelvic radiations and malignant SBO would be important to establishing if what we observed is reproducible, or is a single phenomenon. Until further research is done elevating malignancy in the differential diagnosis of patients with SBO in the setting of prior hernia surgeries and pelvic radiation may be warranted.