Molecular characterization of desmoid tumors: decryption of the enigma.

resolution characterization of chromosomal abnormalities down to the kilobase level, whereas previous studies on desmoid tumors have largely employed techniques suited for the detection of megabase or larger chromosomal alterations [14]. In conjunction with SNP-A, the authors performed traditional DNA sequencing on a number of genes known to be mutated in desmoid tumors, including β-catenin (CTNNB1) and APC. Using these combined methodologies, the authors validated existing data on the presence of mutations in CTNNB1, and losses in chromosome 8q, which contains the APC locus. In addition, they detected numerous other small deletions and insertions that have previously not been reported in desmoid tumors. The most significant of these novel lesions was a heterozygous, somatic deletion affecting a small region of chromosome 8p23, which was observed in 44% of the tumors tested. This deletion falls within the CUB and Sushi multiple domains1 (CSMD1) gene, a putative tumor suppressor that is also mutated or deleted in tumors of the head and neck, colon, breast, and prostate [15, 16]. Furthermore, the authors noted a correlation between CSMD1 deletion and relapse, as 3 of the 9 patients with disease recurrence at the time of publication had exhibited a CSMD1 deletion. The small sample size and short follow-up time limit the authors’ ability to make firm conclusions regarding the prognostic significance of these otherwise exceptional and novel data. The management of desmoid tumors remains a challenge to the patient and the clinician. However, studies such as this by Erben and colleagues add to the arsenal of data that will eventually lead to novel therapies for this disease. As for all patients presenting with complex malignancies such as desmoid tumors, continued efforts for tissue collection and multi-institution and protocol-based regimens are justified.