Morphology of the microvascular bed in primary human carcinomas of lung. Part II. Morphometric investigations of microvascular bed of lung tumors.

A comparative investigations of peripheral microvascular bed in various histological types of human primary lung carcinomas (squamous cell carcinomas, oat-cell carcinomas, adenocarcinomas and large cell carcinomas) have been performed. The study was performed on 52 cases of lung carcinoma (there were 49 cases from autopsy and 3 cases from surgery) and on 8 normal comparative cases for evaluation of unchanged bronchial mucosa. Tissue blocks were obtained from standardized parts of bronchus and contained the intra- and extrabronchial parts of tumour as well as the bordering bronchial mucosa. The relative capacities of: 1. anaplastic cells, 2. connective tissue in stroma, 3. intraluminal space of blood vessels, 4. degenerative anaplastic cells, 5. necrotic detritus, and 6. haemorrhages and erytrorrhages were estimated in carcinomatous tissue by the hit points method. In bronchial mucosa the capacities of: 1. intraluminal space of blood vessels, and 2. haemorrhages and erythrorrhages were recorded. Furthermore, the structure of peripheral microvascular bed was evaluated by constructing the distributive series of diameters of blood vessels. These distributive series were approximated with the analitical function. It was found that the largest capacity of blood vessels (with an extremely developed capillary segment of vascular bed) is in the intrabronchial part of squamous cell carcinomas. In the extrabronchial part of this type of carcinoma, the capacity of blood vessel is about three-times smaller than in the intrabronchial part (3.36% and 9.26%, respectively). The finest blood vessels of extrabronchial part undergo the most considerable reduction, in comparison with the ones in the intrabronchial part of squamous cell carcinoma. Oat-cell carcinomas show the smallest difference in vascularization of intra- and extrabronchial parts of tumor (4.38% and 3.33%, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)