The histological relationships between fibrotic tissue, endometriotic foci and nerves in the rectovaginal septum endometriotic or adenomyotic nodule were studied. This is considered to be one of the most severe forms of deep endometriosis. Masson's trichrome staining for fibrosis detection and immunohistochemistry with the S100 monoclonal antibody for nerve detection were performed in 28 rectovaginal endometriotic nodules from patients presenting with severe dysmenorrhoea and deep dyspareunia (23 patients with no other endometriotic location or potential cause of pain at laparoscopy and ultrasonography; five patients with multiple pelvic endometriotic localizations and other potential causes of pain at laparoscopy). Patients were allocated to two groups on the basis of their preoperative pain scores for pelvic pain, dysmenorrhoea and deep dyspareunia (group 1, score >7; group 2, score < or =7). For each symptom, the mean number of nerves and endometriotic lesions per high-power field and the mean largest diameter of the lesions were not statistically different in groups 1 and 2. The mean percentages of nerves located within the fibrosis of the nodule and within endometriotic lesions were significantly higher in group 1 than in group 2. Among nerves located within endometriotic lesions, there was a significantly higher proportion showing intraneurial and perineurial invasion by endometriosis in group 1 than in group 2. In rectovaginal endometriotic nodules, there was a close histological relationship between nerves and endometriotic foci, and between nerves and the fibrotic component of the nodule. We postulate that such topographical relationships could at least partially explain the strong association between this lesion and pain.

Kaposi's sarcoma (KS) is an angioproliferative disease characterized by proliferating spindle-shaped cells, angiogenesis, and inflammatory cell infiltration. Several lines of evidence suggest that KS is a multifocal cytokine-mediated disease of vascular origin. Because metalloproteinases (MMPs) are important enzymes involved in angiogenesis, we studied their activity in five different KS-derived cell lines and compared these data with those obtained with human umbilical vein endothelial cells (HUVEC). We focused on the activity of the 72- and 92-kd type IV collagenases because these enzymes are thought to play an important role in the process of tumoral invasion. Nonstimulated HUVEC released a weak 72-kd collagenase activity and no 92-kd collagenase activity, as determined by zymographic analysis. Stimulation of HUVEC with phorbol myristate acetate (PMA) or TNF-alpha increased the 72-kd collagenase activity and also induced a 92-kd collagenase activity. By contrast, KS-derived cells constitutively released significant 72- and 92-kd collagenase activities. The basal release of these enzymes by KS cells was further enhanced by TNF-alpha or PMA. Conversely after in vivo exposure to chemotherapy, KS-derived cells showed a downregulation of the production of MMPS that could be reversed by the addition of TNF or PMA. These results suggest that KS cells have constitutive features of activated cells that have an invasive and metastasizing potential.

As the myofibroblast phenotype is not the predominant feature of KS tissues, our findings further substantiate the view that the in vivo dominant endothelial population represents a reactive hyperplasia rather than the true KS tumour process.

Large haemorrhagic and necrotic cutaneous lesions developed after two low dose (5 mg) methotrexate injections in a patient suffering from long standing rheumatoid arthritis. Differential clinical diagnosis included factitia dermatitis, infectious processes, pyoderma gangrenosum, rheumatoid neutrophilic dermatitis, necrotizing arteritis and vasculitis. Histological and direct immunofluorescent examinations of skin biopsies supported the diagnosis of leucocytoclastic vasculitis. We discuss the respective roles of methotrexate and rheumatoid arthritis in the outbreak of leucocytoclastic vasculitis. Hypersensitivity is strongly suspected.