An unusual case of familial adenomatous polyposis with very early symptom occurrence.

We report the clinical case of a patient who showed an "accelerated" form of polyposis, with development of major lesions within the first decade of life. The patient belongs to a familial adenomatous polyposis family-already described in 2001-featured by profuse polyposis at an early age of onset and desmoid tumors in the majority of affected individuals (of both sexes). The family was characterized by an uncommon mutation of the APC gene (c.4391_4700del310insCACCTACTGCTGAAA, previously defined as c.4394ins15del310) consisting in a large deletion of 310 bp at codon 1,464 with duplication of the breakpoint leading to a stop codon at position 1,575. The proband was affected by desmoids tumors at the age of 3 years. In the same year (2004) numerous polyps in the large bowel and a hepatoblastoma developed. After several months new desmoids appeared in the surgical scar. In 2010, at age 9, the patient was operated of total colectomy and endorectal pull-through of the small intestine owing to profuse colorectal adenomatosis. New desmoids developed in 2011 and 2012, and required chemotherapy. Further analysis of the APC gene in the proband revealed several polymorphisms. One of these (c.398A>G) had not been previously reported, nor was present in two other affected members of the family. The clinical case, and the practical implications for therapy, are discussed according to the most recent theories of colorectal cancer development. Long-term treatment with Cox-2 inhibitors might represent a good option for this patient.