Neuro-endocrine cells are a recognised component of prostatic ducts and acini. Half of all clinically manifest cancers show neuro-endocrine differentiation. Occult carcinomas have a lower incidence of such differentiation. Neuro-endocrine cells are of major prognostic importance and appear more reliable in predicting patients' survival than do conventional histological grading systems.

Neuro-endocrine or paracrine cells of the human prostate and urethra have been identified by various methods, predominantly silver stains and immunocytochemistry. The incidence of neuro-endocrine differentiation in prostatic carcinoma has varied considerably from 10 to 100%, but has not been studied previously as an independent factor affecting prognosis. Nucleolar organiser regions (NORs) are loops of ribosomal RNA occurring in the nucleoli of cells which ultimately process RNA genes. NORs have been demonstrated by silver (Ag) staining techniques and have been studied in numerous malignant tumours. A pilot study from this laboratory has shown a distinct and significant difference in AgNOR staining between prostatic carcinoma and benign prostatic epithelial hyperplasia. A retrospective study was performed with at least 6 years' follow-up. This confirmed the presence of neuro-endocrine cells in more than half of the patients under investigation. A significant correlation between survival and the absence of neuro-endocrine cells was demonstrated. AgNOR staining was shown to be of no prognostic value.

TNF alpha and IL-1 secretion in macrophages is required for T and B lymphocytes activation and aggregation; suggesting that macrophages arrive at the scene of rheumatic injury prior to the lymphocytes. IL-2 is usually expressed later in the inflammatory process and was found only in the lymphoid aggregates. This study therefore produces corroborative evidence for our previously proposed developmental stages of the Aschoff nodule.

Rheumatic fever is still the leading cause of acquired heart disease in children and young adults in developing countries. Recent reports have documented a rising incidence of rheumatic fever in both the USA and Europe. The disease is characterized by specific lesions in the heart muscle and valves called Aschoff nodules. The Aschoff nodule has been neglected in the last few decades as most of the studies were conducted in the 1960s on autopsy tissues. This study examines Aschoff nodules using heart valve material obtained at valve surgery with updated commercially available immunohistochemical antibodies to determine the phenotypic characteristics of the cells involved in the formation of these lesions. Fifteen cases of rheumatic valvulitis, as indicated by the presence of Aschoff nodules, were examined. The Anitschkow and Aschoff cells stained prominently with macrophage markers. Three stages of nodules with Aschoff and Anitschkow cells were identified: stage 1, central fibrinoid necrosis without lymphocytes, stage 2 with occasional T lymphocytes (< 10) and stage 3 with lymphoid aggregates containing both T- and B-lymphocytes (with occasional admixed macrophages). We propose that the stage 1 lesion is the earliest granulomatous stage with the lymphoid aggregates being a later stage in the development of Aschoff nodules. The Aschoff and Anitschkow cells demonstrated mitotic activity and stained with antibodies to the proliferation cell nuclear antigen (PCNA) suggesting that the multinucleated giant cells may be formed, at least partially, by nuclear division rather than fusion.