Akademik Veri Yönetim Sistemi
35th European Congress of Pathology, Dublin, İrlanda, 9 - 13 Eylül 2023, ss.344-345
Background & objectives: Lung cancer is currently the leading cause of
cancer-related deaths worldwide. The treatment of lung cancer has been
determined by the histological classifcation and stage. The coexpression
of TTF1 and p40 within the same tumour cells is an exceedingly rare. Methods: We present a rare case of non-small cell lung carcinoma
(NSCLC) with an uncommon histopathological subtype and occurring
at a relatively young age in this study. A 37-year-old female with a twomonth persistent cough presented to the hospital. Imaging revealed a
40x35 mm mass in the right lung’s lower lobe. The resected specimen
exhibited squamous and adenoid areas with intracytoplasmic mucin.
Results: Immunohistochemistry revealed positive expression of TTF1,
p40, CK7, and Napsin A in all cells, ruling out the diagnoses of adenosquamous carcinoma and primary pulmonary mucoepidermoid carcinoma. Based on the literature search, the case was classifed as "NSCLC,
showing biphenotypic features," and was found to be PD-L1 positive.
Visceral pleural invasion and six metastatic lymph nodes were also
identifed, resulting in a stage 2A diagnosis. Next-generation sequencing
detected somatic mutations in the FGFR3 and RB1 genes. The patient
received four cycles of navelbine-cisplatin chemotherapy and is currently
under observation for 15 months without medication. No signs of recurrence or metastasis have been detected in the latest control tomography.
Conclusion: The significance of coexpression of TTF-1 and p40
in NSCLC cells remains unclear. To date, only 19 cases have been
reported, which frequently present with advanced age at presentation.
In most cases, TP53 gene mutation and FGFR1 amplifcation have been
observed. However, our case difers from others reported in the literature
due to its early onset and somatic mutations in FGFR3 and RB1 genes.