Colon biopsies for evaluation of acute graft-versus-host disease (A-GVHD) in allogeneic bone marrow transplant patients.

BACKGROUND: Proper histomorphological interpretation of intestinal acute graft versus host disease (A-GVHD) associated with allogeneic bone marrow transplantation (BMT) is critical for clinical management. However, studies methodically evaluating different histomorphological features of A-GVHD are rare. METHODS: Colonic biopsies from 44 allogeneic BMT patients having biopsy-proven cutaneous A-GVHD were compared with colon biopsies from 48 negative controls. RESULTS: A-GVHD showed intra-cryptal apoptosis in 91% and pericryptal apoptosis in adjacent lamina propria in 70% (p < 0.002). Nonspecific apoptosis along the surface epithelium was observed in all groups with comparable frequency. The number of apoptotic cells in mucosa were approximately four times (5.3 per 10 HPF) the negative controls (p < 0.002) in A-GVHD group. 48% of cases with A-GVHD showed decreased number of lymphocytes in lamina propria. Some features, including intraepithelial lymphocytes in surface or crypt epithelium; and neutrophils, eosinophils, and edema in lamina propria, did not demonstrate significant difference in A-GVHD and negative controls. Pericryptal apoptosis, dilated crypts, irregular distribution of crypts, decreased lymphocytes, increased microvessel network, focal fibrosis, presence of muciphages, reactive changes in surface epithelium with mucin depletion, mucosal ulceration, and/or reduced mucosal thickness showed higher association with A-GVHD group. CONCLUSIONS: Intracyptal apoptosis is a reliable indicator of A-GVHD. Its diagnostic significance was improved if intracyptal apoptosis was associated with features which were observed more frequently in A-GVHD group as mentioned above.

FNAB cytology of chordoma masquerading as adenocarcinoma: case report.

We report a lesion of the mobile spine in a 77-yr-old white male who presented with lower back pain, radiating bilaterally to the legs, with numbness on walking and standing. Magnetic resonance imaging showed a large mass within L3-L4 vertebral bodies; however, chordoma was not suspected or suggested. Fine-needle aspiration biopsy (FNAB) of the mass revealed mostly blood with isolated flat clusters of polygonal rounded epithelial-like cells in a myxoid background. Immunohistochemistry could not be performed on the FNAB specimen due to inadequate material for cell-block. A limited immunocytochemistry panel was performed on one cytology smear. The tumor cells were immunoreactive for cytokeratin. During primary and expert evaluation, these features were interpreted as metastatic adenocarcinoma. Prostate and thyroid were suggested as possible primary sites. An extensive clinical and radiological search did not reveal a primary lesion. Four years later, the patient underwent surgical decompression and stabilization of his lumbar spine to avoid a catastrophic collapse of spine with neurological deficit. Histomorphological features and immunohistochemical studies at this time confirmed the lesion as chordoma. This case highlights the significance of considering chordoma in the differential diagnosis of FNAB cytology of spinal column lesions suggestive of adenocarcinoma, especially when the clusters of low-grade epithelioid cells with vacuolated cytoplasm in a myxoid background do not show epithelial structures such as papillae, glands, or acini.