Molecular analysis of p53 tumor-suppressor gene and microsatellites in preneoplastic and neoplastic lesions of the colon and esophagus.

Mutations in exons 4-8 of the p53 gene by the PCR-SSCP analysis in preneoplastic and neoplastic lesions of the colon (n=11) and esophagus (n=18) were screened. p53 overexpression by immunohistochemistry in 11 colonic lesions and 13 microsatellites, in all the patients (n=29), were also studied. A positive result concordancy between the three techniques was found in 1 adenoma and 2 adenocarcinomas of the colon, each with loss of heterozygocity of microsatellites. Metaplastic lesions of esophagus showed biallelic mutations and low frequency of microsatellite alterations. The relationship between genetic alterations in p53, microsatellites and type of colon and esophageal lesions is discussed.

Adenomas of the colon: overexpression of p53 protein and risk factors.

BACKGROUND AND STUDY AIMS: p53 gene mutation and the ensuing overexpression of its protein is one of the steps related to colorectal carcinogenesis. This study analyzed the relationships between immunohistochemically detected p53 protein accumulation in colonic adenomas and morphological and clinical indicators of risk of malignant transformation and relapse. PATIENTS AND METHODS: A total of 100 endoscopically resected sporadic colonic adenomas (nonpolyposis) from 79 patients were retrospectively studied by using archival paraffin tissue blocks. p53 protein immunohistochemically detected was related to morphological adenoma risk factors (size, histological type and dysplasia) and in patients to neoplastic colonic pathology (NCP), such as previous adenomas/carcinomas or coexistent adenomas. RESULTS: There was a correlation between p53 expression and the grade of dysplasia but not with size or histological type in adenomas. NCP data was present in 52.5% of patients with p53 positive adenomas, and only in 25.6% of patients with p53 negative adenomas. This difference remains even in those with low-grade dysplastic lesions. When coexistent adenoma and previous adenoma/carcinoma data were analyzed separately, similar results were obtained. CONCLUSIONS: The presence of previous and/or coexistent NCP was more frequent in patients with p53 expressing adenomas, even in low-grade dysplastic lesions, which probably could be a high risk subpopulation. Its follow-up may be eventually reviewed.

Quantitative and qualitative AgNORs rates of prostate cancer on needle core biopsies: a multicentric study.

From 1992 to 1993, the Scarpa Foundation Center of Pavia (SFCP) with 12 associated Italian Urological Units selected 40 cases of prostate diseases discovered on needle core biopsies, 5 of which were benign hyperplasias (BPH) in patients without clinical and morphological evidence of cancer and 35 prostate cancers (PRC) classified according to Gleason's histological grades (GLG) of PRC malignancy. Serum prostatic specific antigen (PSA) values were tested before clinical urological examination or biopsy or surgery. In all groups, AgNORs scores/nucleus were obtained by semi- and -automatic computerized image analysis and also by qualitative subjective counts of three observers on light microscopy. Our results pointed out a good correlation between PSA levels, GLG of PRC malignancy and AgNORs scores. The quantitative method showed an average number of AgNORS dots per nucleus between 2 and 3 in well differentiated PRC and higher than 3 in moderately differentiated and undifferentiated PRC, and exhibited more sensitivity over GLG3 than the qualitative investigation. The qualitative subjective count of AgNORs dots/nucleus seemed to be more reliable in differentiating the AgNORs scores of BPH (average of 1.81 dots/nucleus) from very well differentiated PRC with GLG1 + 2(average of 2.25 dots/nucleus) than quantitative analysis, which showed the same average value in both groups (2.11 dots/nucleus). For these reasons, also on needle biopsies of benign and malignant prostate diseases the subjective AgNORs count may aid the histological diagnostic judgement of malignancy, by avoiding misleading diagnoses of microscopic pictures of BPH cancer look likes and a predictive histologic malignant factor, in identifying PRC with low or high progression.

The Aristotelian kidney.

Aristotle incorrectly observed the absence of the kidney in fish and birds and deduced that it was not essential for the existence of a living organism. This underlies his observations on structure and function of the kidney. From examination of rhesus monkeys he generalized that the right kidney is higher than the left. Aristotle did not consider that the renal pelvis is divided by a filter membrane into 2 chambers, and wrote that no blood reaches the renal pelvis. The theory of the 'filter kidney' cannot thus be attributed to Aristotle. The function of the kidney was described as being to separate the surplus liquid from the blood inside the renal meat (not in the renal pelvis) and to transform this liquid into what Aristotle called residuum, i.e. the urine. Aristotle also considered that the kidneys acted to anchor the blood vessels to the body. He only briefly considered renal pathology.

The Medical School at Ravenna.

The existence of the Ravenna School of Medicine can be deduced from a codex in the Ambrosian Library of Milan, which contains Latin translations of 3 Hippocratic works and commentaries on 4 works by Galen. Although it was written in the 9th century, the codex appears to be a copy of an earlier work, probably 7th century. The Ambrosian commentaries follow other commentators on Aristotle, rather than the original Aristotelian works, and contain a number of misinterpretations. Nevertheless, the commentaries make it clear that the earliest literature in Salerno had its roots in the studies of classical medicine at the Ravenna School of Medicine, where the teaching was essentially Galenic in structure.

Early colorectal cancer--follow-up after endoscopic polypectomy.

Approximately 90% of correctly indicated endoscopic polypectomies for early colorectal cancer, whether invasive or not, are curative, provided strict criteria are adopted in the pathological evaluation of the resected specimen. Unrestricted time surveillance is mandatory since benign (more frequent) or malignant relapses appear in 30-40% of the patients.