Tumorigenesis is caused by abnormal proliferation of cells that escape regulatory mechanisms. Most of the molecular events leading to the formation of tumors are still largely unknown. In this paper, experimental data supporting a causative role for cellular genes, termed oncogenes, in the formation of tumors of the nervous system are reviewed. Two types of oncogenes are described: dominant oncogenes, characterized by the fact that one abnormal copy of the gene is sufficient to induce tumorigenesis, and recessive oncogenes which require the inactivation of both copies of the gene to lead to tumor formation. The role of recessive oncogenes in tumorigenesis of the nervous system is illustrated by molecular studies of meningiomas and neurinomas. The mutation of one, and perhaps two loci on chromosome 22, has indeed been shown to be most probably the causative molecular event in the growth of these two tumors when they occur either in their sporadic form, or in neurofibromatosis type 2. All the available data support the proposition of systematically analyzing a large number of tumors to eventually correlate clinical phenotype and evolution, to the genetic abnormalities observed. Furthermore, the understanding of the normal and pathological function of oncogenes should lead to future therapeutical improvements.

Greggi and Kerlikowske have worked out that a woman has a 1.4% chance of developing ovarian cancer during her life. When cancer of the ovary is found, 5 to 10% of these cases have a familial form of this pathology. Thus there are some hereditary forms of cancer of the ovary and Lynch has demonstrated that there are three types of hereditary associations with ovarian neoplastic pathology: specific familial cancer of the ovary, cancer of the ovary associated with endometrial cancer and with non-polypoidal cancer of the caecum and rectum, cancer of the ovary associated with cancer of the breast. The clinical material we are presenting here is of the first type of association and we are reporting the study of a family in which 6 members in two generations had cancer of the ovary and of whom one had cancer of the breast as well. Familial cancer of the ovary shows different characteristics coming on as it does earlier (ten years earlier) and with a shorter length of survival (1.8 as against 5 years). The risk of the next generation having ovarian neoplastic pathology is clear because there is a 50% chance in a patient who has a history of cancer of the ovary in at least two first degree relatives. For most daughters when this type of familial cancer is found it is justifiable to carry out prophylactic oophorectomy from the age of 35 year onwards. Particular supervision should be carried out for patients who are members of a family where 2 index cases have been found within 20-35 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Intratumoral heterogeneity provides information concerning the timing of genetic events which occur during colorectal carcinogenesis. In a series of 14 colorectal adenocarcinomas, the following genetic alterations were characterized: loss of heterozygosity on chromosomes 17 p, 1 p, 18 q, 5 q and 22 q, point mutations on TP53 and K-RAS genes, change in DNA index. Six of the 14 initial samples were investigated for putative genetic heterogeneity. In two cases, variations in genetic alterations on chromosome 17 p and gene TP53 were demonstrated. These events seem to occur at a late stage in colorectal carcinogenesis.

Seventy seven biopsy samples of cervical mucosa were tested for the presence of human papillomavirus (HPV) by immunohistochemistry and in situ hybridization. From the 38 samples identified as condyloma or cervical intraepithelial neoplasia (CIN), 31 were positive after in situ hybridization and 14 after immunochemical analysis. HPV 6 was found exclusively in condyloma acuminata (2 samples) whereas the HPV 16 probe essentially hybridized with high grade intraepithelial lesions (CIN II, CIN III). Low grade intraepithelial lesions (flat condyloma, CIN I) demonstrated a larger diversity of HPV types (HPV 16, 18, 31, 33). A close correlation was demonstrated between the histologic features of lesions and their HPV 6 or HPV 31 content but not for other HPV types. HPV 31 containing lesions showed a peculiar architecture with numerous, elongated papillae resulting in a spiked appearance.

We report a severe case of Sturge-Weber syndrome in one of two monozygotic twins. This syndrome included a facial portwine stain over the trigeminal ophthalmic V1 area, and ipsilateral vascular anomalies of the eye and of the pia mater. CT scans and MRI were very informative. The cerebral regional blood flow, studied with SPECT, showed a paradoxically high rate.

Blue Rubber Bleb Naevus (BRBN) is characterized by the presence of bluish haemangiomas on the skin and in the digestive tract. We report a new familial case of this rare entity. Analysis of this female patient's pedigree confirmed that BRBN is transmitted as an autosomal dominant trait. In this particular case gastrointestinal haemangiomas appeared over a 4-year period. Although all treatments of this disease have proved disappointing on the skin as well as in the digestive tract, we insist on the need for a regular and prolonged surveillance.