Medullary thyroid carcinoma with diabetic ketoacidosis: an autopsy case report and literature review.

Medullary thyroid carcinoma (MTC) is a rare neuroendocrine tumor of parafollicular C cells. The majority of MTCs occur sporadically, but about 30% of the cases are associated with multiple endocrine neoplasia type 2 (MEN2) syndrome or familial MTC. Generally, MTCs have no clinical manifestation, but infrequently the patients develop symptoms of hypercortisolism by secreting adrenocorticotropic hormone (ACTH) or corticotropin-releasing hormone (CRH). Although ectopic Cushing syndrome is only found in 0.7% of MTC patients, it can lead to fatal consequences if left untreated. Over 50 cases of MTC-related Cushing syndrome have been reported, and few autopsy cases exist in the literature. In those cases, the tumor cells are positive for calcitonin, but mostly display negative immunostaining for ACTH or CRH. The authors report an autopsy case of a 22-year-old woman who was found dead with no medical history whose cause of death was diabetic ketoacidosis associated with MTC, which showed poor calcitonin stainability.

Renal cell carcinoma metastatic to follicular adenoma of the thyroid gland. A case report.

BACKGROUND: Renal cell carcinoma is an unpredictable tumor that can recur many years after the original diagnosis and metastasize to uncommon sites, including the thyroid gland. Differential diagnosis from primary thyroid tumor is often difficult both clinically and pathologically. We report a case of metastatic renal cell carcinoma in follicular adenoma of the thyroid gland. CASE: A 48-year-old woman presented with a 3-cm-diameter, palpable mass in the left lobe of the thyroid gland. The patient's history included removal of a left renal mass, which was conventional renal cell carcinoma. Fine needle aspiration cytology smears contained a few small clusters of polygonal cells with abundant, clear cytoplasm and irregular, hyperchromatic nuclei as well as bland-looking thyroid follicle cells and stromal cells. A papillary or follicular growth pattern was not detected. A cell block made from the aspirated sample was composed mainly of clear cells. By immunohistochemical stains, the clear cells were completely negative for TTF-1, thyroglobulin, calcitonin and inhibin while equivocally staining for cytokeratin, CD10 and galectin-3. The histologic diagnosis was renal cell carcinoma metastatic to follicular adenoma of the thyroid gland. CONCLUSION: Renal cell carcinoma metastatic to the thyroid may masquerade as a primary thyroid neoplasm. A history of prior nephrectomy, the presence of unremarkable thyroid follicle cells, the absence of a papillary or follicular growth pattern and immunohistochemical study can help differentiating metastatic renal cell carcinoma from a primary thyroid lesion with clear cell change.

Pure non-gestational choriocarcinoma of the ovary diagnosed by DNA polymorphism analysis.

Pure primary ovarian choriocarcinoma is a rare condition that can be of gestational or non-gestational origin. Non-gestational choriocarcinoma has been found to be resistant to single-agent chemotherapy and has a worse prognosis than gestational choriocarcinoma, but it is difficult to distinguish the two types by routine histological examination. Herein is reported a case of primary pure non-gestational choriocarcinoma of the ovary in a 33-year-old nulligravid woman, as confirmed by DNA polymorphism analysis. All tested microsatellite markers had identical DNA profiles with the same allelic sizes between the tumor and the myometrium of the patient, who was homozygous for three markers (BAT26, BAT25 and D17S250) and heterozygous for four (D2S123, D18S57, DCC and D18S58), supporting non-gestational origin. The patient has no evidence of disease 17 months after surgery and four cycles of combination chemotherapy. This case demonstrates the usefulness of DNA polymorphism analysis for the determination of the origin of extrauterine choriocarcinoma. Clinical relevance of this method needs to be further studied and substantiated.

A case of ACTH-producing pheochromocytoma associated with pregnancy.

Ectopic ACTH syndrome is rarely caused by pheochromocytoma. We report a case of a 28-year-old woman with Cushing's syndrome due to ACTH-producing adrenal pheochromocytoma. She had delivered preterm baby at 32nd week of gestation with 'severe preeclampsia'. After delivery, persistent hypertension accompanied by severe headache led her to being misdiagnosed as Cushing's syndrome due to right adrenal adenoma (normal plasma ACTH level) and cerebral vasculitis of unknown etiology. She was referred to our hospital for surgical treatment. Repeated biochemical studies suggested coexistence of ectopic ACTH syndrome and pheochromocytoma. To reverse her clinical deterioration, right total and left subtotal adrenalectomy was performed with presumptive diagnosis of 1) right adrenal pheochromocytoma causing ectopic ACTH syndrome or 2) coexistence of ACTH-dependent Cushing's syndrome and right adrenal pheochromocytoma. Pathologic examination of right adrenal mass revealed pheochromocytoma which showed strong immunostaining for ACTH. Plasma ACTH and urinary cortisol excretion normalized after surgery, but she succumbed to multiple cerebral infarcts and disseminated intravascular coagulation. Pregnancy and inappropriately low plasma ACTH at initial evaluation might have hampered early diagnosis. To our knowledge, this is the first description of a case with ectopic ACTH syndrome due to pheochromocytoma associated with pregnancy.