Comparison of tumor density by CT scan based on histologic type in lung cancer patients.

AIM To investigate the differences of tumor density of lung cancer by CT scan based on histopathologic type of cancer cell. METHODS Subjects were lung cancer patients at Dr. Kariadi hospital Semarang between January 2002 and December 2003. Diagnosis was made based on clinical symptoms, histologic examination and lateral chest radiograph, and thorax CT scan. Density of tumor was measured within area which had most enhancements before and after contrast administration. Then, it was followed by transthoraxic fine needle aspiration (TNFNAB) and histopathologic examination. Study design was a cross sectional study. Inclusion criteria were primary lung cancer and exclusion criteria were non lung cancer, metastatic cancer, histopathologic non interpreted. Estimated number of samples was 41 patients. Density value before and after contrast were analyzed using Wilcoxon signed rank test. Difference of tumor density for each type of cancer cell was analyzed using chi-square test with significant level at p < 0.05 and confidence interval of 95%. RESULTS Forty-one patients with lung cancer were enrolled in this study. There were 30 males (73.2%) and 11 females (26.8%). Histopathologic types of cell cancer were epidermoid in 17 patients (14.5%), adenocarcinoma 8 patients (19.5%), large cell 7 patients ( 17.1%), small cell 7 patients ( 17.1%) and undifferentiated cell 2 patients ( 4.5%). Mean of increasing HU before and after contrast in epidermoid carcinoma was 26.8 (10.4) HU, adenocarcinoma 17.2 (7.1) HU, large cell 8.7 (4.5) HU, small cell 9.9(4.1) HU and undifferentiated cell 23.5 (1.5) HU with overall increase of all cancer cell types was 17.3(9.2) HU, p < 0.001. Histopathologic type of non small cell lung carcinoma (NSCLC) with density < 60 HU was found in 30 patients (73.2%) and small cell lung carcinoma with density > 60 HU was found in 5 patient (12.2%), p=0.01. CONCLUSION There was evident increase of density in all histopathologic type of cell cancer, p < 0.0001, with mean of density after contrast administration was 17.2 (7.1). There was significant difference between NSCLC and SCLC group and tumor density > 60 HU and < 60 HU, p=0.01.