Proliferating cell nuclear antigen expression is increased in small bowel epithelium in the elderly.

Although previous studies suggest that in aging animals the small intestine is in a hyperproliferative state, no information is currently available on the influence of age on the proliferation pattern of human small bowel enterocytes. The immunohistochemical expression of the proliferating cell nuclear antigen (PCNA), the villous height to total mucosal thickness ratio and the enterocyte height were evaluated in a panel of duodenal biopsy specimens obtained from 18 subjects aged less and 14 subjects aged more than 65 years. There was a significant positive correlation (P < 0.001) between age in years and percent of positive PCNA enterocytes both at the level of crypts (rs = 0.50) and villi (rs = 0.77). Moreover, the percentage of PCNA+ enterocytes was significantly higher in elderly versus adult subjects, both at the level of villi (6.5 vs 0%; P < 0.001) and of crypts (40.0 vs 23.7%; P < 0.01). No correlation was found between the percentage of PCNA + enterocytes and enterocyte height or villous height to total mucosal thickness ratio. Our results show that PCNA reactivity increases with advancing age both in crypts and villi. This abnormality of the proliferation pattern may explain the coexistence of normal morphology and impaired absorptive function in the elderly.

Mucinous cystadenoma of the lung.

A 56-year-old male patient came under our observation when a peripheral round mass in his right lung which he had since 1991 and which was believed to be a bronchogenic cyst, showed a volumetric enlargement of 2 cm. After performing a lobectomy of the middle lobe, the histopathological examination revealed the presence of a mucinous cystadenoma of borderline malignancy.

[Importance of bronchial biopsy in the histologic typing of cancer of the lung. Case study contribution (1980-1987)]. / Il significato della biopsia bronchiale nella tipizzazione istologica del cancro polmonare. Contributo casistico (1980-1987).

The diagnostic significance of the histological typing of lung cancer carried out on preoperative bronchoscopic biopsy samples is assessed in relation to final morphological diagnosis on operating material. In this connection 176 of 624 cases of lung cancer documented histologically from January 1980 to December 1987 in which preoperative biopsy sample was followed by removal of the lung are analysed. The 4 basic histotypes of lung cancer according to the WHO (1981) classification are considered. A positive diagnosis for cancer was encountered in 138 cases (78.4%) with histotype confirmed in 122, whereas a negative diagnosis was encountered in 38 cases (21.6%). These findings also permitted further considerations, including the possible limitations of the technique.