Affiliations: Department of Telepathology, The National Research Institute of Tuberculosis and Lung Diseases, Warsaw, Poland | III Department of Tuberculosis and Lung Diseases, The National Research Institute of Tuberculosis and Lung Diseases, Warsaw, Poland | I Clinic of Psychiatry, Medical Academy, Warsaw, Poland
Abstract: BACKGROUND: The studies on the therapeutic effect on the disease pattern and morphologic heterogeneity of small cell lung carcinoma (SCLC) provide some explanation for unresponsive behaviour of SCLC to chemotherapy. The aim of the study was to assess the distribution of SCLC disease and variation of the histological SCLC subtypes in relation to the therapy, in post-mortem specimens. METHODS: The autopsies of 85 SCLC patients (pts) treated with various therapy regimes, 15 untreated SCLC pts and 85 diagnostic biopsy samples of treated SCLC pts were reviewed to assess the distribution of the disease and the histological subtypes of SCLC (IASLC classification). RESULTS: The modalities of therapy were related to status of the primary tumour. The chemo-radiotherapy significantly decreased the presence of macroscopic primary focus in comparison with chemotherapy alone (p=0.03); and significantly increased the frequency of the residual tumour (p=0.026). Six of 45 (13%) pretreated pure SCLC changed their morphology into mixed SCLC or combined SCLC in autopsy postreated tumours. The heterogeneity in distribution of pure SCLC, mixed SCLC and combined SCLC subtypes was present in comparative analysis of primary tumour and its metastases. CONCLUSION: The modalities of therapy influence status of the locoregional disease but do not influence the metastatic pattern of SCLC. The findings indicate that pretreated pure SCLC can progress to mixed SCLC or combined SCLC in postreated cancer, exhibiting a mixed differentiation in the metastases.
Keywords: small cell lung cancer, therapy, histological subtypes, autopsy