Ring chromosome may signal progression of Fanconi anemia

Fanconi anemia (FA) is a genomic instability disorder associated with high risk of AML. Ring chromosomes are results of genomic instability and observed in many human neoplasias. The present study aimed to assess the role of ring chromosome in the progression of FA.

The study included 60 patients with provisional diagnosis of FA. A total of 5 ml of venous blood was collected and processed for complete hemogram, peripheral blood film, and breakage test. Patients with positive breakage test were followed-up every 3-months interval for a maximum of 24 months. Subsequently, 2 ml of BM aspirate was collected to determined BM morphology, and cytogenetic analysis.

Of the 60 patients, 21 (35%) showed positive breakage test including ring chromosome in 4 (19%) patients. During the follow-up of the 21 FA patients, the 4-patients with ring chromosome developed AML within the interval of 8-14 months. However, another patient without ring chromosome developed AML after 23 months of the diagnosis. BM analysis showed non-random clonal chromosomal abnormalities such as del (20) (q11) in 3 cases; add(1)(q12); -7, -8, and +9 in one case each. Normal karyotype was seen in the 5th patient without ring chromosome.

The present study suggested that the ring chromosome formation in FA may single the progression of the disease. Thus, early BM transplant for patients with ring chromosome is crucial to avoid the development of AML.