Intestinal-Type Adenocarcinoma Is a Rare Histotype of Vulvar Neoplasm: Systematic Review of the Literature

Intestinal-type vulvar adenocarcinoma (VAIt) is an exceptionally rare form of primary vulvar cancer, characterized by histological features resembling mucinous colonic carcinomas, including villo-glandular structures composed of goblet and Paneth cells with intracytoplasmic mucin.

To provide a comprehensive synthesis of the existing literature on VAIt and to also report a case from our institution in order to define its clinical, pathological, and immunohistochemical characteristics and its management and prognosis.

A systematic review of the literature according to PRISMA guidelines was performed through searching five electronic databases (MEDLINE, EMBASE, Web of Science, SCOPUS and Cochrane Library), considering studies from 1998 to May 2025. In our research, we included all peer-reviewed studies which reported cases of VAIt. Data about VAIt were extracted by included studies and compared.

All in all, 32 studies with a total of 40 cases (including our case) of VAIt were assessed. The median age at diagnosis was 58 years. Most tumors arose in the labia or perineal structures, often mimicking benign lesions. Immunohistochemistry consistently showed CK20 and CDX2 positivity, with variable CK7 and p16 expression. FIGO stage IA was the most frequent stage at diagnosis. Surgical excision was the mainstay of treatment, while adjuvant therapy was less commonly reported. Lymph node metastases were present in about 31.5% of cases. Despite aggressive histology, most patients were disease-free at follow-up. Mortality due to disease occurred in 10% of cases.

VAIt is a very rare histotype of vulvar cancer. Compared to vulvar squamous cell carcinomas, approximately 40% of early-stage clinical diseases reported in the literature presented positive inguinal lymph nodes with recurrence even after many years. The optimal treatment is not well defined and should be based on the individual clinical history of the patient, as there are no established guidelines. Further studies and longer follow-up periods are needed to clarify the best therapeutic management and its long-term prognosis.