17P Deletion Test Cost & Procedure

Patients with chronic lymphocytic leukaemia have an uncommon chromosomal defect called deletion 17p (del 17p) (CLL). Del 17p can occur up to 50% of the time in patients with relapsed/refractory illness, compared to 5% to 9% of newly diagnosed CLL patients.

Del 17p is associated with a poor response to conventional therapy and a bad outcome.  We designed this study since there is a dearth of information from India regarding del 17p in CLL patients. This study's objective is to understand the prevalence of del 17p and the clinico-hematological characteristics of Indian CLL patients.

The initial workup included routine biochemistry, lactate dehydrogenase, B2 microglobulin, IgVH mutation status, clinical and hematological parameters (full hemogram, peripheral blood smear examination, and flow cytometry), and fluorescence in situ hybridization (FISH) for del 17 p.

According to the manufacturer's instructions, 17p deletion was detected by FISH in peripheral blood samples at the time of diagnosis using the dual-color Zytolight TP53/Cen17 probe (Zytovision, GmbH, Germany). At tiny 200 interphase nuclei from each issue were examined Positive cases were those with less than 7.5% of nuclei. The Rai staging system was used to group patients into stages.

16 (11.4%) of the 140 patients that were selected for the study had del 17 p. These patients' traits are enumerated below. Ten of the patients who tested positive for del 17p at baseline got CLL therapy, while six others were maintained under observation. Four individuals received bendamustine rituximab, one patient received fludarabine cyclophosphamide and rituximab, one patient received chlorambucil and prednisolone, and four patients received ibrutinib in the subgroup of patients who underwent treatment. In the 10 patients whose IgVH mutation status was known (sequences with a germline identity 98% were regarded unmutated), 8 patients had unmutated IgVH.

This study is the first one from India to assess the prevalence of del 17p using the FISH method. Our analysis detected del 17p in 11.4% of CLL patients who had never received treatment, which is greater than the rate noted in the western literature. This might be caused by referral bias at our facility or a variation in the biology of the disease. Comparing the patients with 17p deletion to the historical data from our centre reveals that they were younger (53 vs. 59 years), had a higher male preponderance (7:1 vs. 3:1), a higher total leukocyte count (60,000 vs. 50,000/mm3), and had more advanced disease (50% vs. 40%) at presentation. The lack of other cytogenetic abnormalities detectable by FISH restricts the scope of this investigation.