Spontaneous Regression of a Hypernephroma

Spontaneous regression of malignant tumours, wherein healing is complete or includes the larger part of a tumour, is very rare. Bash-ford estimated that it occurs but once in one hundred thousand cases. The case which came to our attention was a large tumour of the kidney that had undergone necrosis and calcification. The patient was a woman of sixty-one years, whose symptoms were related to the gastro-intestinal tract. A large, fixed mass was palpable in the left upper abdomen; no pain nor tenderness was elicited. X-ray examination disclosed a retroperitoneal, calcareous, cystic mass in the left upper abdominal quadrant, displacing the spleen upward, forward, and laterally, with the stomach overlying it anteriorly. In the stomach, a large indentation was seen on the greater curvature, apparently resulting from the pressure of the mass. Pyelography showed the left kidney displaced downward, and it was thought, that the mass could be visualized as lying above and behind the displaced kidney. The upper calices were dilated, and distorted, apparently by the pressure of this mass. The right kidney pelvis and calices were normal. Both kidneys were functioning normally and the urine contained no cells. The greater part of the mass, as seen by x-ray, was spherical in shape, with, however, a knob-like process the size of a small orange projecting from its lower extremity. The dimensions of the shadow were 8 1/2″ × 5 1/2″. The origin of the tumour was not definitely determined, although it was thought not to be a primary tumour of the kidney.