[Polyps (single or multiple) and juvenile polyposis]. / Polipi (singoli o multipli) e poliposi giovanile.

The authors underline the important aspects of juvenile familial polyposis (JFP), a disease transmitted as an autosomal dominant trait. A case of JFP characterized by the presence of hundreds of polyps in the colo-rectal intestinal tract, is analyzed. The single juvenile polyp, multiple polyps (=/>5 polyps) and the sporadic form are examined. These are mucous hamartomas which can undergo neoplastic transformation (in carcinoma in 68% of untreated cases), a behaviour similar to that of adenomatous polyps. They differ from the later due to the following features: epidemiology (earlier appearance age), anatomopathology (stroma), clinical observation (self-recovery in some cases) and genetics (10q23.3-18q21, genetic mutations in a locus different those of adenomatous polyps). It is also necessary to determine its extension by means of colonoscopy, ileoscopy, gastroscopy and small bowel barium enema. Patients' screening through construction of the genealogical family tree is fundamental. Isolation of possible degenerative aspects of the polyps through biopsy is also fundamental. Single or multiple polyps are treated endoscopically, the juvenile polyposis is treated surgically (colectomy, total colectomy). A rigorous follow-up of the patients and their family members is recommended.

Biological effects of preoperative radiotherapy on metastatic lymph nodes from rectal cancer.

The quantitative description of the proliferative activity of cancer cells correlates with the aggressiveness of malignant tumors. The aim of this retrospective study was to determine the biological effect of adjuvant therapy on metastatic lymph nodes from rectal cancer and to compare the results between patients treated with surgery alone and patients treated with preoperative radiotherapy. Expression of the proliferating cell nuclear antigen (PCNA) was examined in metastatic lymph node samples of 12 rectal cancer patients receiving and 14 patients not receiving preoperative radiotherapy. PCNA immunostaining was performed by an avidin-biotin complex immunoperoxidase technique. The results of the mean proliferation index (PI) between the two groups were compared. A semiquantitative PCNA grading system was also estimated. In patients receiving preoperative radiotherapy, the PI was 22.8 per cent, and only one patient had high proliferative grade. On the contrary, the PI in nonirradiated patients was 67.6 per cent, and nine patients showed high proliferative grade. Although not sufficient to reach significance in terms of prognosis, the present study confirms the clinical value of radiation therapy, and it supports the suggestion to treat Dukes' C patients with preoperative radiotherapy to decrease the risk of local recurrence.