150P - Immunohistochemical characteristics of brain metastases and corresponding primary lung cancer

Date 07 May 2017
Event ELCC 2017
Session Poster Display Session
Topics Thoracic malignancies
Presenter Dora Marinova
Citation Annals of Oncology (2017) 28 (suppl_2): ii52-ii55. 10.1093/annonc/mdx094
Authors D. Marinova1, Y. Slavova1, S. Nachev2, D. Dimitrova1, E. Mekov1, M. Mihailov1, D. Kostadinov1, V. Youroukova1
  • 1Pulmonology, University hospital for pulmonary diseases St. Sofia, 1431 - Sofia/BG
  • 2Pathology, University Hospital St. Ivan Rilski, Sofia/BG

Abstract

Background

About 40% of patients with lung cancer (LC) develop brain metastases (BM). The prognosis is poor. The study of BM is important for better understanding of the biology of LC.

Methods

Surgically resected BMs and corresponding primary LCs from 30 patients (men n = 25, 83%; age 55±9) were studied: adenocarcinoma (AC)-21, squamous cell carcinoma (SCC)-5, small cell lung carcinoma (SCLC)-4. The histological subtype and immunohistochemical expression of TTF-1, p63, cytokeratin 7, synaptophysin, Ki-67 (proliferative activity) and CD31 (number intratumoral microvessels-NIM) were evaluated.

Results

The histology of LC compared with BM is different in half of the AC and without difference in SCC and SCLC. ACs are mainly with acinar (53% cases) and solid (37%) components. Metastatic ACs are more often with papillary (47%) component. In 47% of AC BM has different histological structure than LC. The acinar AC are predominantly papillar in 70% of BM showing that the papillary component metastasize most frequently. TTF-1 is expressed in greater number of lung AC (n = 20, 95%), but with lower mean levels of expression, while the corresponding BM express the marker less frequently (n = 16, 76%), but when it is presented it has higher mean values of expression (45.44 vs73.88, p = 0.011). P63 is expressed in high percentage in all SCC (n = 5,100%); there is no difference in expression between LC and BM (80.6 vs 81.6, p = 0.68). Cytokeratin 7 is expressed in all AC equally regardless of the site - primary or metastatic. Ki-67 proliferative index (PI) is higher in SCLC than in lung AD (p = 0.008), in SCLC BM than in AD BM (p < 0.001), in SCLC BM than in SCC BM (p = 0.008). It was found that the Ki-67 PI BM is higher than that of AC LC (30 vs. 17, p = 0.003), in SCC (35 vs.27, p = 0.048) but without difference in SCLC (p = 0.141). CD31 establish vascular invasion in LC – NIM is higher in AC than in SCLC (55vs.31, p = 0.003), in SCC than in SCLC (61vs.31, p = 0.009), no difference between AC and SCC (66 vs.61, p = 0.467). There were no significant differences between LC and BM.

Conclusions

There are differences between primary LC and corresponding BM – in histology structure, in immunohistochemical expression, and in proliferative activity.

Clinical trial identification

Legal entity responsible for the study

Medical University, Sofia.

Funding

Supported by Grant 360/2015-Contract Nr.76/2015 funded by Medical University, Sofia.

Disclosure

All authors have declared no conflicts of interest.