Carcinoma of lung with special reference to adenocarcinoma (an autopsy study of 122 cases).

We report morphological observations on 122 autopsied cases of lung carcinoma during the years 1974-1989, with emphasis on 44 cases of adenocarcinoma. Adenocarcinoma was the commonest histological type encountered (36%), confirming the trend reported in Western countries. It was also noted that nearly 50% of cases of adenocarcinoma were in the central zone, which is contrary to reported literature. 92% of small cell carcinoma, 87% of epidermoid carcinoma, 64% of combined carcinomas and 48% of adenocarcinomas were centrally located, while 91% of bronchioloalveolar carcinomas and 88% of large cell carcinoma were located peripherally. Of the 44 cases of adenocarcinoma, 23 were peripheral and 21 were central. In ten out of the 21 cases of central adenocarcinoma the tumour was confined to the bronchial tree without any parenchymal involvement. This type of gross morphology has not been described in adenocarcinoma so far. In the other 11 cases, there was a tumour in the lung parenchyma involving the bronchus. In these cases, it was not possible to decide whether bronchial involvement was primary or secondary, but bronchial obstruction due to a polypoid mass was present in three of these cases.

Association of lung carcinoma and tuberculosis.

Two hundred and twenty one consecutive cases of bronchogenic carcinomas were studied histologically for evidence of associated lesions. Seventy eight lesions were seen in 55 patients (24.8%). The most frequent was tuberculosis, seen in 29 patients. The next in frequency were scars, in 22, emphysema in 12 and thickened pleura in 7. Interstitial fibrosis, chronic bronchitis, lobar pneumonia and bronchiectasis, were other lesions, seen in very few cases. The types of carcinoma, in which associated lesions seen were, undifferentiated carcinoma (76%), adeno-carcinoma (56%), mixed tumor (37%), large cell anaplastic (25%), small cell anaplastic (23.7%) and epidermoid carcinoma in (5.44%). The incidence of tuberculous lesions in autopsies unassociated with tumor is 7%, as compared to 24.8% incidence of association with carcinoma; which is significant. There were seven scar cancers; with origin in tuberculous scars in two. The study indicates necessity of prospective study in this field.