Atypical Co-amplification with Co-localization of HER2 Gene in Breast Cancer: Combined IHC/FISH Approach as per ASCO/CAP 2018 Guidelines for Targeted Therapy Eligibility.

Breast cancer patients with HER2 gene amplification as assessed by FISH are eligible for HER2-targeted therapy. However, in a small subset of patients, unusual FISH pattern of co-localization and co-amplification can pose challenges in interpretation of the HER2 status and hence to assess the HER2 status accurately; our aim was to report their incidence and analyze them based on latest ASCO/CAP 2018 guidelines. We present seven cases with HER2/CEP17 co-amplification and co-localization from a total 4040 cases referred during the year 2017 to 2021 at Mumbai Reference Laboratory, SRL Diagnostics.

Atypical MYC rearrangement pattern of 3' deletion and 5' amplification along with independent IGH rearrangement: A case study.

A spectrum of Cellular homolog of the v-myc oncogene (cMYC) alterations such as translocation, overexpression, mutation, and amplification plays an important role in lymphomagenesis, particularly in high-grade lymphomas, and are associated with prognostic significance. Accurate identification of cMYC gene alteration is important for diagnostic, prognostic, and therapeutic implications. With the application of different FISH (fluorescence in situ hybridization) probes that helped overcome the analytical diagnostic challenges as a result of variant patterns, we report rare, concomitant, and independent gene alterations in cMYC and Immunoglobulin heavy-chain gene (IGH) with detailed characterization of its variant rearrangement.