Metastatic malignant phaeochromocytoma: A rare entity that underlies a therapeutic quandary

Haemorrhagic retroperitoneal paraganglioma initially manifesting as acute abdomen: a rare case report and literature review

BACKGROUND

Paragangliomas (PGLs) are extremely rare neuroendocrine tumours arising from extra-adrenal chromaffin cells. PGLs are clinically rare, difficult to diagnose and usually require surgical intervention. PGLs mostly present catecholamine-related symptoms. We report a case of Acute abdomen as the initial manifestation of haemorrhagic retroperitoneal PGL. There has been only one similar case reported in literature.

CASE PRESENTATION

We present a unique case of a 52-year-old female with acute abdomen induced by haemorrhagic retroperitoneal PGL. The patient had a 5-h history of sudden onset of serve right lower quadrant abdominal pain radiating to the right flank and right lumbar region. Patient had classic symptoms of acute abdomen. Abdominal ultrasound revealed a large abdominal mass with a clear boundary. A Computed Tomography Angiography (CTA) of superior mesenteric artery was also performed to in the emergency department. The CTA demonstrated a large retroperitoneal mass measured 9.0 × 7.3 cm with higher density inside. A provisional diagnosis of retroperitoneal tumour with haemorrhage was made. The patient received intravenous fluids, broad-spectrum antibiotics and somatostatin. On the 3rd day of admission, her abdominal pain was slightly relieved, but haemoglobin decreased from 10.9 to 9.4 g/dL in 12 h suggesting that there might be active bleeding in the abdominal cavity. Thus, we performed a midline laparotomy for the patient. Haemorrhage was successfully stopped during operation. The retroperitoneal tumour with haemorrhage was completely removed. The abdominal pain was significantly relieved after surgery. The patient initially presented with acute abdomen instead of catecholamine-related symptoms. The diagnosis of retroperitoneal PGL with haemorrhage was finally confirmed by postoperative pathological and immunohistochemical results. The postoperative course was uneventful. At the 1-year follow-up visit, no tumour recurrence was observed by Single Photon Emission Computed Tomography. A literature review was performed to further understand and analyse the aforementioned disease.

CONCLUSION

Acute abdomen as the initial manifestation of haemorrhagic retroperitoneal paraganglioma is extremely rare. Abdominal Computed Tomography is essential to locate the lesion and differentiate between other causes of acute abdomen. PGLs are hypervascular tumours. We should be aware that ruptured retroperitoneal PGL with massive bleeding could be life threatening and require emergency laparotomy.

Combination chemotherapy regimen in a patient with metastatic malignant pheochromocytoma and neurofibromatosis type 1

Patient: Female, 55

Final Diagnosis: Metastatic malignant pheochromocytoma

Symptoms: Chest pain • tachycardia • tachypnea

Medication: —

Clinical Procedure: —

Specialty: Oncology

Plasma free metanephrines in healthy cats, cats with non-adrenal disease and a cat with suspected phaeochromocytoma

Phaeochromocytomas are catecholamine-secreting tumours of the adrenal glands and are rare in cats. Plasma metanephrine levels are widely considered the diagnostic test of choice for phaeochromocytoma in people but have not been investigated in cats. In this study plasma free normetanephrine and metanephrine levels were measured using high-pressure liquid chromatography in healthy cats, sick cats with non-adrenal disease and in a cat with a suspected phaeochromocytoma. Plasma normetanephrine was significantly higher in sick cats with non-adrenal disease compared to healthy cats (P<0.05) and markedly higher in the cat with a suspected phaeochromocytoma when compared to either group. Plasma metanephrine was not significantly different in any of the groups. This study establishes a first-line guide reference range for plasma metanephrine and normetanephrine levels in healthy cats and cats with non-adrenal disease. These results provide rationale for further studies to establish the use of plasma normetanephrine levels as a potential diagnostic test for phaeochromocytoma in the cat.