Rare digital tumours: two case reports and mini review.

Masses within the fingers and hands are a common occurrence affecting patients of all ages. Although most will be benign conditions, rarer more aggressive tumours also occur. Two cases of rare hand tumours, a digital myofibroma and an aggressive digital papillary adenocarcinoma are reported here including a mini-review of the literature. Although these two cases are quite different they highlight the importance of having a high index of suspicion for the presence of malignant change in masses that have been quiescent for considerable periods of time and thus the need for histological diagnosis in masses resected from the hands. The myofibroma, like other conditions such as giant cell tumours, although benign can have very worrying clinical features, most notably bony destruction. The aggressive digital papillary adenocarcinoma conversely can appear benign clinically but biologically is very aggressive with a high propensity for local and distant spread.

Tubulo-vascular relationships in the developing kidney.

The postnatal development of the tubulo-vascular relationships in the kidney was studied in 60 rats. The kidney is relatively immature at birth and only the juxtamedullary glomeruli are present. As their loops of Henle develop they grow down into the medulla around the previously developed collecting ducts, forming tubulovascular 'units' around whose periphery the shorter loops of the more peripheral glomeruli grow down. The bundles of vasa recta develop in loose interstitial tissue which lies between the tubulo-vascular units so that the peripheral vessels of the bundles, which are ascending vasa recta, lie in close relationship with the descending short loops of Henle. Thus, the vascular bundles do not form the central axis around which the medullary components develop but rather take up the available space left after the tubulo-vascular units have developed. Development is virtually complete by the fourth week of postnatal life.