RESUMEN
INTRODUCTION: Paragangliomas are neuroendocrine tumors that most commonly originate in the adrenal gland, a type that is called pheochromocytoma; however, 5-10% of paragangliomas are extra-adrenal and may arise in any area between the neck and pelvic region along the sympathetic nervous system. Those located in the head and neck comprise 3% of extra-adrenal tumors, with the majority originating in the tympanic-jugular region and carotid body. OBJECTIVE: To present a rare case of nasal paraganglioma and review the literature. CASE REPORT: The patient was submitted to medial subtotal maxillectomy, and her clinical findings, diagnostic data, and treatment outcome were recorded. CONCLUSION: Paragangliomas are considered benign tumors, but they occasionally display a malignant character. The most important finding in this case was the need for total resection of the tumor to avoid recurrence.
RESUMEN
BACKGROUND: Apoptosis is a particular form of cell death involved in the elimination of somatic cells. In this study, the occurrence of apoptotic cells in kidney and pancreas allograft biopsies was analyzed and correlated with the number of infiltrating macrophages and lymphocytes and granzyme B expression. METHODS: Kidney and pancreas biopsies from patients submitted to simultaneous pancreas-kidney transplantation were classified into three groups: acute rejection, chronic rejection, and transplant cases without evidence of rejection. Formalin-fixed paraffin biopsies were used to identify apoptosis by the terminal deoxynucleotidyl transferase [TdT]-mediated dUTP nick end labeling (TUNEL) method. RESULTS: In normal kidney, only few apoptotic cells were observed. In contrast, in kidney-allograft biopsies, the TUNEL signal was detected in the nuclei of tubular epithelial cells and also in mononuclear cells scattered in the interstitium. In pancreas biopsies, numerous apoptotic cells were detected in acinar cells, in ducts, and occasionally in islets. The number of apoptotic cells in acute pancreas rejection was significantly higher compared with acute rejection of kidney grafts (50+/-14 vs. 21+/-4 cells/mm2; P<0.05). In kidney biopsies, there was a positive correlation between apoptosis and macrophages (r=0.51; P<0.005), and apoptosis versus T lymphocytes (r=0.45; P<0.05). In pancreas biopsies, the number of apoptotic cells correlated only with the number of macrophages (r=0.41; P<0.05). CONCLUSIONS: Apoptosis occurs in kidney and pancreas allograft biopsies, markedly in acute rejection in pancreas biopsies. Although apoptosis may reflect a mechanism of down-regulation of the allograft immune response by eliminating infiltrating cells, the elimination of graft cells may result in graft damage, particularly in pancreas transplantation.
