Among patients with bone marrow failure, differentiating acquired aplastic anemia (AA) from hypocellular refractory anemia (hypo RA) can be a difficult and challenging task. Morphological, cytochemical, immunocytochemical, and cytogenetic studies may provide tools for discriminating between both entities. In addition, differences in the pattern of proliferation and apoptosis of bone marrow cells in AA and in the myelodysplastic syndrome have been reported. Because of the correlation between p53 and apoptosis, we examined the overexpression of p53 on bone marrow biopsies in RA and AA. Our study included 14 patients with hypo RA, 14 patients with hypercellular (hyper) RA, ten patients with classic acquired AA, and 37 hematologically normal individuals. p53 was overexpressed in eight (57%) hypo RA patients and 11 (79%) hyper RA patients. All normal individuals and patients with AA showed no overexpression of p53 in their marrow. These results were statistically significant:p < 0.01 (AA vs hypo RA), p<0.001 (AA vs hyper RA), while the difference between hypo RA and hyper RA was not statistically significant. We conclude that p53 overexpression in bone marrow biopsies is a valuable tool for studying bone marrow failure and may provide additional information to help differentiate hypo RA from acquired AA.

Microcystic adenoma is an uncommon neoplasm of the pancreas usually affecting older people. Its histologic features have been well characterized. The cytologic appearance of this tumor has been described only rarely, however. Microcystic adenomas may enlarge considerably and often produce symptoms related to their compression to adjacent anatomic structures. The fact that this neoplasm is almost always benign indicates the need for accurate preoperative diagnosis to differentiate it from other, more common, malignant or potentially malignant tumors of the pancreas. We present a case of pancreatic microcystic adenoma initially diagnosed by percutaneous image‐guided fine‐needle aspiration cytologic examination and core biopsy and further evaluated by endoscopic ultrasound‐guided fine‐needle aspiration on follow‐up. This case report illustrates that microcystic adenoma of the pancreas can be accurately diagnosed by aspiration cytology. Fine‐needle aspiration—percutaneous, guided by computerized tomography, or endoscopically guided by ultrasonography—constitutes a reliable and cost‐efficient diagnostic tool associated with minimal trauma to the patient. Diagn. Cytopathol. 1998;20:298–301. © 1999 Wiley‐Liss, Inc.

Microcystic adenoma is an uncommon neoplasm of the pancreas usually affecting older people. Its histologic features have been well characterized. The cytologic appearance of this tumor hasKey Words: microcystic adenoma; pancreas; fine-needle aspiration; endoscopic ultrasound-guided fine-needle aspiration Although it is relatively uncommon, the majority of pancreatic cysts are non-neoplastic acquired lesions regarded as inflammatory pseudocysts. Cystic neoplasms of the pancreas constitute 5-15% of pancreatic cysts 1 and are referred to as cystadenomas. Malignant cystic tumors of the pancreas are regarded as cystadenocarcinomas. Pancreatic cystic neoplasms are classified into two main groups: microcystic adenoma (MA) and mucinous cystic neoplasms. 2 Pancreatic MA is also known as serous cystadenoma and glycogen-rich cystadenoma. 1 MA is a rare, usually benign pancreatic neoplasm with distinct gross and histologic features. It affects elderly people and tends to be found slightly more often in women. MA is a slow-growing tumor arising in the pancreatic head, body, or tail. Several series account for different favored locations of MA in the pancreatic head, 1,2 or tail. 3 Tumors arising in the body or tail of the pancreas are typically larger than those confined to the pancreatic head owing to their usual clinical presentation at a later time. 4 Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a highly accurate, cost-effective technique currently used in the diagnosis of pancreatic and other anatomic site masses. 5 This novel technique uses a fiberoptic endoscope that contains a retractable needle, which can be guided into the target lesion in real time by an ultrasonic probe. EUS-FNA is particularly useful for sampling lesions that cause external compression to the pancreatic ducts without involvement of the mucosa. 6 The cytologic appearance of MA on FNA has only rarely been described. [7][8][9] To our knowledge, the current case constitutes the first time the cytomorphologic features of MA have been reported on a specimen obtained by EUS-FNA.