Primary neuroendocrine tumor in the presacral region: A case report

A Case Report of Neuroendocrine Tumor in Presacral Region: How Can It Be Managed? Laparoscopy versus Laparotomy

Presacral or retrorectal tumors are rare, usually asymptomatic, and diagnosed accidentally during physical examination or imaging. Symptomatic tumors may present with perianal pain, bowel dysfunction, and urinary symptoms due to the mass compression or invasion of the surrounding tissues and organs. Surgical resection is the first choice for treating presacral tumors. Clinicians should choose surgical procedures based on the location and size of the tumors. We presented a 43-year-old woman who suffered from pelvic pain and primary infertility from two years ago. A large mass between the posterior vaginal wall and the rectum was found on recto-vaginal examination. Magnetic resonance imaging (MRI) revealed a large 120×115 mm benign multiloculated cystic mass. Eventually, the mass was removed through laparoscopic surgery. The pathology report indicated a carcinoid tumor (grade I) with no lymphovascular invasion. Thus, presacral tumors are resectable through laparoscopy with lower complications than open surgery.

Multicenter Analysis of Presacral Neuroendocrine Neoplasms-Clinicopathological Characterization and Treatment Outcomes of a Rare Disease

Background and Aims

Neuroendocrine neoplasms (NENs) of the presacral space are an extremely rare disease entity with largely unknown outcome and no established standard of care treatment. Therefore, we wanted to analyze clinical presentation, histopathological findings, treatment outcomes, and prognosis in a multicentric patient cohort.

Methods

We searched local databases of six German NEN centers for patients with presacral NEN. Retrospective descriptive analyses of age, sex, stage at diagnosis, symptoms, grade, immunohistochemical investigations, biomarkers, treatment, and treatment outcome were performed. Kaplan-Meier analysis was used to determine median overall survival.

Results

We identified 17 patients (11 female, 6 male) with a median age of 50 years (range, 35-66) at diagnosis. Twelve cases presented initially with distant metastases including bone metastases in nine cases. On pathological review the majority of patients had well-differentiated G2 tumors. Immunohistochemical profile resembled rectal NENs. All but one patient had non-functioning tumors. Somatostatin receptor imaging was positive in 14 of 15 investigated cases. Eight patients were treated surgically including palliative resections; 14 patients received somatostatin analogs with limited efficacy. With 14 PRRTs completed, 79% showed clinical benefit, whereas only one patient with neuroendocrine carcinoma (NEC) responded to chemotherapy. Treatment with everolimus in three patients was not successful, whereas cabozantinib resulted in a disease stabilization in a heavily pretreated patient. During a median observation period of 44.5 months, 6 patients died. Median overall survival was not reached.

Conclusion

Presacral NEN are histopathologically similar to rectal NENs. Presacral NEN should be considered as possible primary in NEN of unknown primary. The majority of tumors is non-functioning and somatostatin receptor positive. PRRT demonstrated promising activity; tyrosine kinase inhibitors warrant further investigations. Further molecular characterization and prospective evaluation of this rare tumor entity are needed.