Chinese Journal of Medical History / Zhong Hua Yi Shi Za Zhi

[This article belongs to Volume - 54, Issue - 02]

Abstract : A potential cause of tolerance in lung carcinoma is histologic alteration. The most frequent histological alteration is the transition from small cell carcinoma (SCC) to adenocarcinoma (AdenoCa) in response to tyrosine kinase inhibitors (TKI). There is a significant research imbalance on the involvement of treatment modalities in histological alterations. The current study aims to investigate histologic changes in lung cancer that are not small cells. The molecular profiles of primary and modified cancers were also compared. When the tissue was available, we used exome sequencing to compare the molecular profiles of the original and altered tumors. We looked into the histological changes in six cases following different treatments. Following EGFR-TKI, the original mutations in two adenocarcinoma cases that transformed into SCC were still present. The identical genetic differences between the two different non-small cell carcinomas (NSCC) were seen in all four cases. Histologic modifications were seen in two patients; following therapy, the altered tumors either reverted to their original subtype or merged. Mixed histology was seen in two cases in the first or second alteration. The study concludes that different treatment modalities can alter the NSCC histology to a single pattern or a mix of subtypes, and the phenotypic alterations don't last forever. As such, additional morphologic alterations may occur regardless of their genetic makeup and course of treatment. Sequential repeat biopsies are essential to fine-tune the new treatment plan in recurrent tumors or progressive disease cases.