Schwannoma and Leiomyoma of the Colon in a Patient with Ulcerative Colitis

Current status of the diagnosis and treatment of gastrointestinal schwannoma

Gastrointestinal schwannoma is a rare, slow-growing and benign tumor that mostly originates in the Auerbach myenteric nerve plexus in the gastrointestinal tract. The clinical manifestations may be associated with the location, size, differentiation type, and degree of malignancy of the tumor. Endoscopy, ultrasound and imaging examinations serve an important auxiliary role in the clinical identification, diagnosis and differential diagnosis of lesions; assessment of risk; and preparation for surgery. S-100 positivity is a hallmark of schwannoma. CD34, CD117, discovered on GIST-1, P53, ALK, β-catenin, smooth muscle actin and Desmin negativity are helpful for the identification of other gastrointestinal stromal tumors. Surgical removal of the tumor is the main treatment for schwannoma. Benign gastrointestinal schwannoma has a good prognosis without recurrence and metastasis; malignant transformation is extremely rare and has a poor prognosis.

Total laparoscopic surgery for treatment of leiomyoma of the transverse colon in a patient with an abdominal mesh: A case report

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Leiomyomas of the colon are rare and account for 3% of gastrointestinal leiomyomas.

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The patient had an abdominal mesh from a prior surgery.

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Laparoscopic colectomy was used for treatment of leiomyoma of the transverse colon.

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Laparoscopic colectomy prevented damage to the abdominal mesh.

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Total laparoscopic surgery is a viable option in patients with abdominal mesh.

Introduction

Gastrointestinal stromal tumors are the most common mesenchymal tumors of the gastrointestinal tract; however, gastrointestinal leiomyomas are relatively rare. Surgical resection is recommended for leiomyomas and gastrointestinal stromal tumors of the colon. We present a case in which we performed laparoscopic right hemicolectomy with intraabdominal anastomosis for treating leiomyoma of the transverse colon in a patient with an abdominal mesh.

Presentation of case

A 64-year-old woman with a history of right subtotal adrenalectomy and right mastectomy was incidentally found to have an abdominal mass on a follow-up computed tomography (CT) scan, which was confirmed as a gastrointestinal stromal tumor of the mesentery following abdominal contrast-enhanced CT. We planned surgical resection for preoperative diagnosis because the tumor was >5 cm in diameter. However, she had undergone transverse rectus abdominis myocutaneous (TRAM) flap reconstruction after right mastectomy, in which the TRAM flap was replaced with an abdominal mesh; hence, total laparoscopic surgery was performed to avoid damaging the mesh owing to the risk of mesh infection. Laparotomy revealed that the tumor originated from the transverse colon; thus, transverse colectomy with intraabdominal anastomosis was performed. The total operative time and blood loss were 3 h 32 min and 5 mL, respectively. No postoperative leakage or mesh infection was observed. The resected specimen revealed a leiomyoma without malignancy.

Discussion

We successfully performed colectomy that minimized the resection range and intraabdominal anastomosis.

Conclusion

Total laparoscopic surgery was effective for colonic leiomyoma with an abdominal mesh to avoid mesh-related complications.

Schwannoma of the colon and rectum: a systematic literature review

Background

Schwannomas of the colon and rectum are rare among gastrointestinal schwannomas. They are usually discovered incidentally as a submucosal mass on routine colonoscopy and diagnosed on pathologic examination of the operative specimen. Little information exists on the diagnosis and management of this rare entity.

The aim of this study is to report a case of cecal schwannoma and the results of a systematic review of colorectal schwannoma in the literature.

Main body

PubMed, Scopus, and Cochrane database searches were performed for case reports and case series of colonic and rectal schwannoma.

Ninety-five patients with colonic or rectal schwannoma from 70 articles were included. Median age was 61.5 years (59% female). Presentation was asymptomatic (28%), rectorrhagia (23.2%), or abdominal pain (15.8%). Schwannoma occurred in the left and sigmoid colon in 36.8%, in the cecum and right colon in 30.5%, and in the rectum in 21.1%. Median tumor size was 3 cm and 56.2% of patients who underwent preoperative colonoscopy had a typical smooth submucosal mass. At pathology, 97.9, 13.7, and 5.3% of schwannomas stained positive for S100, vimentin, and GFAP, respectively. The median mitotic index was 1/50.

Conclusions

Colorectal schwannoma is a very rare subtype of gastrointestinal schwannoma which occurs in the elderly, almost equally in men and women. Schwannoma should be included in the differential diagnosis of a submucosal lesion along with gastrointestinal stromal tumor, neuro-endocrine tumors, and leiomyoma-leiomyosarcoma. Definitive diagnosis is based on immunohistochemistry of the operative specimen. Rarely malignant, surgery is the mainstay of treatment.