1/54. Adrenocortical oncocytoma.The histopathology and ultrastructural features of an adrenocortical oncocytoma are reported. The tumour was discovered incidentally during investigation for hypertension in a 72 year old female. Oncocytic tumours of the adrenal cortex are rare, with only 20 examples described in English language reports. Most have been non-functioning and benign, like the present example. Molecular studies may help assess the significance of oncocytic change in the pathogenesis and behaviour of oncocytic neoplasms.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
2/54. Oncocytoid renal cell carcinoma after neuroblastoma: a report of four cases of a distinct clinicopathologic entity.Four children who developed oncocytoid renal cell carcinoma (RCC) after neuroblastoma are reported. One patient had multiple, bilateral RCCs. The mean age at time of diagnosis of RCC was 8.8 years (range, 5-13 years). The mean interval between neuroblastoma and RCC was 7.15 years (range, 3.1-11.5 years). The histologic findings of these RCCs did not fit within the spectrum of known renal epithelial neoplasms. Most of the neoplastic cells in all cases had eosinophilic, oncocytoid cytoplasm and were arranged in solid and papillary growth patterns. A subset of cells with reticular cytoplasm was also present. Immunohistochemical studies demonstrated keratins 8 and 18 in all neoplasms and keratin 20 in two cases. dna ploidy analysis revealed that two of three neoplasms assessed were aneuploid. Cytogenetic studies revealed 45, XX, add or dup (7)(q32q36) in one neoplasm, and 83-89, XXXX, -1 ,-3, del (3)(q11.1q2?1), der(4)t(4;?22) (q32;q11.2), -14, -22 in a second tumor. Microsatellite polymerase chain reaction analysis detected no abnormalities in one neoplasm and allelic imbalance of chromosomes 2p31-32.2, 8p22, 9p22-24, 13q22, 20q13, and 22q11 in a second tumor. In case 4, two different RCCs excised 6 months apart were analyzed. The initial neoplasm showed allelic imbalance of chromosomes 2q31-32.2, 5q22, 5q31, 10p13-14, 13q22, 14q31, and 20q13. The subsequent neoplasm showed allelic imbalance of chromosomes 3p21.3, 14q31, and 20q13. The common presence of 14q31 and 20q13 abnormalities suggests that these two neoplasms were genetically related. In aggregate, these findings are distinctive, are not found in known types of RCC, and support the morphologic impression that oncocytoid RCC after neuroblastoma is a distinct clinicopathologic entity.- - - - - - - - - - ranking = 8keywords = neoplasm (Clic here for more details about this article) |
3/54. GANT-like gastrointestinal pacemaker cell tumours with oncocytic features.We describe two cases of gastrointestinal stromal tumours with prominent oncocytic features. Both had features consistent with differentiation towards the interstitial cells of cajal (CC). They were composed of nests and bundles of cells with abundant, deeply granular, eosinophilic cytoplasm. Immunohistochemical investigations revealed positivity with c-kit, vimentin and CD34 antibodies in both neoplasms. Ultrastructurally the neoplastic cells showed characteristic features of CC; they had synapse-like structures and dense core cytoplasmic granules. Oncocytic features were confirmed by immunohistochemistry using anti-mitochondrion antibody in both cases and by electron microscopy in one case (case 1). Although the CC are frequently described as mitochondrion-rich cells, oncocytic changes have not previously been reported as a feature of gastrointestinal autonomic nerve tumour (GANT)-like stromal tumours.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
4/54. Hurthle cell adenoma of the mediastinum: intraoperative cytology and differential diagnosis with correlative gross, histology, and ancillary studies.A 66-year-old man was found to have a 7.5 cm mediastinal mass detected on routine chest x-rays as part of his preoperative work up for an inguinal hernia repair. An orthotopic (normally located) nongoitrous thyroid gland without evidence of connection to the mediastinal mass was also identified. The clinical differential diagnoses included lymphoma, thymoma, and germ cell tumor. Fine-needle aspiration (FNA) biopsy smears and touch imprints of the mediastinal mass showed a loosely cohesive, highly cellular population of relatively uniform cells with abundant granular cytoplasm, low nuclear to cytoplasmic (N/C) ratios, and prominent nucleoli consistent with a Hurthle cell (HC) neoplasm. Subsequently, the diagnosis of HC adenoma was confirmed on the surgically excised mediastinal mass. To the best of our knowledge, the surgical pathology and cytologic features of an HC adenoma of the mediastinum have not been reported in the literature. The gross, histologic, immunohistochemical, and electron microscopic (EM) findings, in addition to the cytologic features, are presented along with a differential diagnosis of this mediastinal neoplasm.- - - - - - - - - - ranking = 2keywords = neoplasm (Clic here for more details about this article) |
5/54. Tumor metastasis to an oncocytoma.A case of squamous carcinoma of the lung metastatic to a renal oncocytoma is described. The terms "tumor-to-tumor metastasis" and "collision tumor" for describing the existence of two neoplasms in the same location are discussed.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
6/54. Granular-cell tumor of trachea masquerading as Hurthle-cell neoplasm on fine-needle aspirate: a case report.We report on a case of extraluminal tracheal granular-cell tumor which was interpreted as a Hurthle-cell neoplasm of the thyroid on fine-needle aspirate. review of the literature reveals only one other such case. The patient was a 35-yr-old female who presented with an enlarged thyroid. Aspiration cytology revealed a syncytium of cells with abundant granular cytoplasm interpreted as a thyroid follicular neoplasm with Hurthle-cell change. However, histology of the resection specimen with immunohistochemistry confirmed it as a granular-cell tumor. The cytologic differential diagnosis of neoplasms with oncocytoid cytoplasm in and around the thyroid should include granular-cell tumor of the trachea.- - - - - - - - - - ranking = 7keywords = neoplasm (Clic here for more details about this article) |
7/54. Follicular carcinoma of the thyroid with extensive clear-cell differentiation: a potential diagnostic pitfall.Clear-cell features have been recognized in several different thyroid neoplasms. A case of thyroid follicular carcinoma with extensive clear- and Hurthle-cell features is described in a 37-yr-old white female, with cytochemical and immunohistochemical analysis. The tumor of the thyroid gland, with anterior neck soft-tissue extension, displayed clear cells on fine-needle aspiration, which were negative for thyroglobulin. The surgical specimen displayed predominately clear cells (80%), and only the nonclear-cell areas stained for thyroblobulin. Proper categorization of clear-cell lesions of the thyroid and soft tissues requires a multimodality approach, involving clinical/pathological correlation, morphological analysis, and ancillary tissue studies. Immunohistochemical stains for thyroglobulin are quite definitive in making the distinction between primary clear-cell thyroid tumors vs. metastatic clear-cell tumors. Cytologists should be aware, however, that the clear-cell areas of thyroid tumors might not stain for thyroglobulin.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
8/54. Follicular carcinoma of the thyroid with extensive clear-cell differentiation: a potential diagnostic pitfall.Clear-cell features have been recognized in several different thyroid neoplasms. A case of thyroid follicular carcinoma with extensive clear- and Hurthle-cell features is described in a 37-yr-old white female, with cytochemical and immunohistochemical analysis. The tumor of the thyroid gland, with anterior neck soft-tissue extension, displayed clear cells on fine-needle aspiration, which were negative for thyroglobulin. The surgical specimen displayed predominately clear cells (80%), and only the nonclear-cell areas stained for thyroglobulin. Proper categorization of clear-cell lesions of the thyroid and soft tissues requires a multimodality approach, involving clinical/pathological correlation, morphological analysis, and ancillary tissue studies. Immunohistochemical stains for thyroglobulin are quite definitive in making the distinction between primary clear-cell thyroid tumors vs. metastatic clear-cell tumors. Cytologists should be aware, however, that the clear-cell areas of thyroid tumors might not stain for thyroglobulin.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
9/54. Oncocytoma in melanocytoma of the spinal cord: case report.OBJECTIVE AND IMPORTANCE: Oncocytoma in the central nervous system is extremely unusual. The first reported example of oncocytoma in a melanocytoma of the spinal cord was successfully excised, and its pathological appearance is described. CLINICAL PRESENTATION: A 71-year-old woman presented with a 25-year history of back pain and myelographic evidence of a lumbar spinal cord mass. After declining surgical treatment for two decades, she elected eventually to have the mass excised. Preoperative magnetic resonance imaging revealed a large intraspinal mass that spanned spinal levels L3 through S1. TECHNIQUE: The mass was excised en bloc through posterior laminectomies, and histopathological analysis revealed a benign neoplasm composed predominantly of monotonous sheets of plump oncocytes. Electron microscopy confirmed that the cytoplasm of the oncocytes was packed full of mitochondria. Focal areas of the tumor contained spindle cells, with abundant intracytoplasmic granular deposits of brown melanin pigment that contained melanosomes. Positive Fontana-Masson, HMB-45, and S-100 staining confirmed the final diagnosis of melanocytoma, oncocytic variant. CONCLUSION: The first reported case of oncocytoma arising in spinal melanocytoma is described. After surgical excision, the patient recovered completely and has remained free of symptoms for 4 years.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
10/54. Bronchial oncocytoma.CONTEXT: Oncocytomas are generally small and present slow growth. Finding of the tumor usually occurs incidentally. Their incidence is higher among male patients. Oncocytomas in mucous bronchial glands are extremely rare. CASE REPORT: A 35-year-old male who presented bronchial oncocytoma. The tumor was found after bronchoscopy that investigated an atelectasis of the upper left lobe. Histological examination with optical microscopy revealed a mature neoplasm formed by ovoid cells with thin, granular, eosinophilic cytoplasm and small nuclei similar to oncocytes. Electron microscopy showed mitochondrial hyperplasia. A three-year follow-up after thoracotomy followed by lobectomy and removal of the bronchial tumor was uneventful.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
| | Next -> |