A rare case of extra-adrenal pheochromocytoma localized to the ovary and detected via abdominal computed tomography angiography

A Comprehensive Analysis Identified the Key Differentially Expressed Circular Ribonucleic Acids and Methylation-Related Function in Pheochromocytomas and Paragangliomas

We investigated differentially expressed circular RNAs (circRNAs) and their potential functions in pheochromocytomas and paragangliomas (PCC/PGLs). Expression levels of circRNAs in tumor and adjacent normal tissues from seven PCC/PGL patients were analyzed through RNA sequencing. Real-time PCR was conducted to verify the key candidates identified in the sequencing data. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to predict the functions of these circRNAs. A total of 367 circRNAs were found differentially expressed between tumor and normal samples. The top three histone methylation-related circRNAs (hsa_circ_0000567, hsa_circ_0002897, and hsa_circ_0004473) and their target microRNAs (miRNAs) were identified and validated. We then mapped the circRNA-miRNA-messenger RNA (mRNA) coding-noncoding gene co-expression (CNC) networks to show the potential binding relationships between circRNAs and their targets in PCC/PGLs. The top five mRNAs, 88 miRNAs, and 132 circRNAs related to pathogenesis were utilized to map the CNC network, and we observed that the interactions of these candidates with their target miRNAs regulated histone methylation and further mediated PCC/PGL pathogenesis. This study is the first to provide the whole profile of differentially expressed circRNAs in PCC/PGLs. Our data indicate that altered circRNAs may control the pathogenesis of PCC/PGLs by regulating histone methylation processes, highlighting their role as potential biomarkers.

Peritoneal carcinomatosis from ovarian paraganglioma: Report of a rare case and systematic review of the literature

Paraganglioma is one of the rarest neoplasms involving the ovary, with only 10 previous reports. We present a case of peritoneal carcinomatosis from primary ovarian paraganglioma and a systematic review of the literature. Clinical information was retrieved from medical records, and a systematic review of the literature was performed according to meta-analysis of observational studies in epidemiology guidelines. A 33-year-old woman presented with a 12-month history of hypertension and weight loss. She was diagnosed with ovarian paraganglioma and was treated with extensive debulking surgery to no residual disease after three cycles of neoadjuvant chemotherapy. She recurred after 6 months and was started on somatostatin-analogue. Following further disease progression with bone metastasis (treated with palliative radiotherapy), a trial with Sunitinib was started. The patient died 30 months after initial diagnosis. Of the cases reported to date, only one had peritoneal metastasis at presentation but none of them had such an ominous prognosis. Ovarian paraganglioma is an extremely rare condition. We report the first case of primary malignant ovarian paraganglioma with an exceptionally aggressive behavior. Clinicopathological correlation with immunohistochemistry is essential to avoid misdiagnosis. A standard treatment is not recommended yet but cytoreductive surgery seems to be a favorable approach to prolong survival.

Clinical and Pathological Features of Pheochromocytoma in the Horse: A Multi-Center Retrospective Study of 37 Cases (2007-2014)

Background

Pheochromocytoma is the most common adrenal medullary neoplasm of domestic animals, but it is rare in horses. Antemortem diagnosis in horses is difficult, with clinical signs often being vague or non‐specific.

Objective

The objective of this study was to describe the clinical, laboratory, and pathologic findings of pheochromocytoma in horses.

Animals

Thirty‐seven horses diagnosed with pheochromocytoma based on postmortem examination from 2007 to 2014.

Methods

Retrospective case series.

Results

Pheochromocytoma was identified in 37/4094 horses during postmortem examination. Clinical signs consistent with pheochromocytoma had been observed antemortem in only 7 cases, with the remainder being incidental findings. Colic was the most common presenting complaint (13 of 37 cases) and tachycardia was noted in 95% of cases (median heart rate of 86 bpm in clinical cases). Hyperlactatemia (median, 4.9 mmol/L) and hyperglycemia (median, 184 mg/dL) were the most common clinicopathologic abnormalities. Hemoperitoneum caused by rupture of pheochromocytoma was noted in 4/7 clinical cases. Concurrent endocrine abnormalities (eg, thyroid adenoma, adrenal hyperplasia, pituitary pars intermedia hyperplasia or adenoma, parathyroid C‐cell carcinoma) were found in 27/37 horses, with 8/37 horses having lesions consistent with multiple endocrine neoplasia syndrome as described in humans.

Conclusions

Pheochromocytoma was diagnosed in 0.95% of horses presented for necropsy. The majority of these were incidental findings, but pheochromocytoma was thought to contribute to clinical findings in 19% of cases, and multiple endocrine neoplasms were commonly seen. Usually an incidental finding at necropsy, pheochromocytoma may cause acute death from intraperitoneal exsanguination and should be considered in horses presenting with colic, tachycardia, and hemoperitoneum.