INTRA-ABDOMINAL FIBROMATOSIS OF THE DESMOID TYPE. A TUMOR UNDER THE GUISE OF PSEUDOPROGRESSION

A.A. Aniskin1, S.A. Peschanskaya1, A.S. Ivanova1, Z.Z. Mamedli1, A.S. Gorbunova1, D.V. Kuzmichev1, A.I. Kapkova2

1N.N. Blokhin National Medical Research Center of Oncology, Moscow

2Moscow Scientific Research Oncological Institute named after P.A. Herzen, Moscow

Aniskin A.A. — PhD (Medicine), researcher, Department of abdominal oncology No. 3 (coloproctology)

23 Kashirskoe shosse, 115478 Moscow, Russian Federation, e-mail: Docaniskin@gmail.com, ORCID ID: 0000-0002-6123-3903

Abstract. Desmoid fibromatosis (DF) is a rare neoplasm of connective tissue that develops in muscular-aponeurotic tissues. The disease symptoms may vary depending on the tumor localization. The most common genetic disorder in DF is a mutation in the APC gene (adenomatous polyposis coli gene).

We present a rare clinical case of abdominal desmoid fibromatosis in a patient with colorectal cancer.

When new formation of abdominal cavity is detected in a patient with cancer, it is recommended to conduct a molecular genetic analysis using the appropriate genetic panels (in particular, a study of mutations in the APC and CTNNB1 genes), with mandatory comparison of the results with clinical and morphological data.

Abdominal desmoid fibromatosis should be included in the preoperative differential diagnosis when unspecified abdominal neoplasms are detected, despite the rarity of this disease. This approach facilitates timely diagnosis, adequate treatment selection, and prevention of overly radical or insufficient interventions.

The clinical case was recorded using the CARE criteria. Informed consent from the patient was obtained.

Key words: desmoid tumor, desmoid fibromatosis, APC gene, colorectal cancer.