Central and Peripheral Squamous Cell Carcinoma of the Lung. Are They Different?
Hisao Sano, Tomonori Tanaka, Junya Fukuoka. Toyama University Hospital, Toyama, Japan
Background: Lung squamous cell carcinoma (SCC) can be classified into the central type (cSCC) and the peripheral type (pSCC) according to the location. Referring to recent reports, pSCC may be biologically different from cSCC, but the evidence is weak. If they are biologically different, treatment should be considered separately.
Design: 50 cases with SCC resected by lobectomy from 2005 to 2010 in Toyama University hospital in Japan were collected. In histologically, cSCC was defined as a tumor from trachea to segmental bronchi and pSCC as in more peripheral location. Pathologic reports were reviewed for age, sex, location, smoking status, pathologic stages, differentiation, pleural invasion, and vascular invasion. H&E slides were reviewed to score levels of necrosis, keratinization, inflammatory cell infiltration, alveolar filling pattern inside the tumor, emphysema, and fibrosis outside the tumor. Tissue Microarray containing triplicated 0.6mm cores from each case were composed. Immunohistochemical staining for CK7, TTF1, p63, CK14, Napsin A, CK34βE12, CK5/6, and p53 were performed. Levels of entrapped pneumocytes inside the core were also scored by observing CK7.
Results: The numbers of cSCC and pSCC were 15 and 35, respectively. Strong male predominance (48:2) and association to smoking history (46/48) were observed. Most of the histological findings did not separate cSCC and pSCC, whereas presence of severe emphysema only showed statistically predominance in pSCC (p=0.02). Immunohistochemical patterns were also identical, and none showed statistically significant difference between cSCC and pSCC. Observed difference was a presence of entrapped pneumocytes highlighted by CK7 predominantly in pSCC (p=0.04). The-5-year survival showed no difference in the prognosis between cSCC and pSCC.
Conclusions: Immunohistochemical patterns and survival are not different between cSCC and pSCC. The central and peripheral SCC may not be biologically different except the ways of proliferation. Emphysema may increase the risk of carcinogenesis possibly due to its localized poor clearance of carcinogenic agents.
Monday, March 19, 2012 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 298, Monday Morning