 |
Vol.62 No.2 contents | Japanese/English |
 | Full Text of PDF (1022K) Article in Japanese |
- Case Report -
Two Cases of Squamous Cell Carcinoma with Co-expression of TTF-1 and p40 in the Same Tumor Cells Identified Immunohistochemically
Ryosuke Kamimura1, Hidehito Matsuoka1, Yukio Kashima2, Ryota Dokuni3, Tatsunori Kiriu3, Keiko Okuno3, Yoshikazu Kotani31Department of Thoracic Surgery, 2Department of Diagnostic Pathology, 3Department of Respiratory Medicine, Hyogo Prefectural Awaji Medical Center, Japan
Background. We examined two cases of non-small cell lung carcinoma with co-expression of TTF-1 and p40 in the same tumor cells. However, the cases were diagnosed as squamous cell carcinoma at a later date because of negative immunohistochemical (IHC) staining with a different TTF-1 antibody clone. Case Reports. Case 1: An 82-year-old man was referred to our hospital with left back pain. Chest computed tomography (CT) revealed a 41-mm nodule in the S6 segment of the left lung, which was diagnosed as non-small cell carcinoma (cT2bN0M0 stage IIA), so we performed thoracoscopic left lower lobectomy. We pathologically diagnosed the tumor as non-small cell carcinoma with co-expression of TTF-1 and p40. Case 2: A 65-year-old man was referred to our hospital with the complaints of dyspnea and dysphagia. Chest CT revealed a 44-mm mass at the tracheal bifurcation. A biopsy led to a diagnosis of non-small cell carcinoma with co-expression of TTF-1 and p40. However, repeat IHC staining with a different TTF-1 antibody clone at a later date led to a change in the diagnosis to squamous cell carcinoma for both cases 1 and 2 because of negative staining for TTF-1. Conclusion. TTF-1 expression differs between clones. We should not use clone SPT24 but rather clone 8G7G3/1 for distinguishing adenocarcinoma from squamous cell carcinoma.
key words: TTF-1, p40, Co-expression, Squamous cell carcinoma
Received: April 28, 2021
Accepted: November 11, 2021
JJLC 62 (2): 97-102, 2022
