Oncocytic tumor of the pancreas. Report of a case with aspiration cytology.

The fine needle aspiration (FNA) cytologic findings in a case of pancreatic oncocytoma are reported, and the differential diagnoses are discussed. The FNA picture was consistent with an oncocytic, acinar or islet cell neoplasm; electron microscopy was required to make the definitive diagnosis. The partially cystic tumor measured 7 cm and occurred in the head of the pancreas in a 63-year-old man with symptoms related to compression of the common bile duct. The clinical findings in this and a few other known cases indicate that the malignant potential of pancreatic oncocytoma may be low. Thus, it is important to distinguish this type of tumor from the cytologically similar acinar carcinoma of the pancreas, which has a poor prognosis in general.

In vivo measurements of relative motion between an uncemented femoral total hip component and the femur by roentgen stereophotogrammetric analysis.

Roentgen stereophotogrammetric analysis (RSA) was used to study rotation and subsidence of an uncemented polyethylene-coated femoral component for total hip arthroplasty in ten patients younger than 55 years of age. Three years postoperatively, the total subsidence averaged 2.44 mm and the internal rotation was 7.4 degrees. The rate of subsidence decreased between the observation periods, whereas the rate of rotation, after an initial significant decrease, became almost constant. One patient, who was a clinical failure and required revision arthroplasty, had a significantly higher rate of migration after six months. The pattern of subsidence in the absence of pain might be the normal reaction of bone to an uncemented prosthesis, but the continuing rotation suggests the potential for failure of the arthroplasty. The type of analysis made possible in RSA may allow early prediction of the success of arthroplasties and significantly speed the design cycle for arthroplasty components.