Brief report: Advanced paraganglioma: A role for chemotherapy?

Rationale and evidence for sunitinib in the treatment of malignant paraganglioma/pheochromocytoma

CONTEXT

Paragangliomas are tumors that develop from extraadrenal chromaffin cells. Approximately 20% of paragangliomas are malignant, and surgical resection is considered the primary treatment when possible. The optimal systemic treatment for advanced disease is undefined, due in part to lack of effective agents. Here we report our experience suggesting that sunitinib is an effective agent in this malignancy.

SETTING AND PATIENTS

Three patients with metastatic paraganglioma were treated with sunitinib at the Princess Margaret Hospital. Limited analyses of tumor tissue and germline DNA were available.

INTERVENTION

Sunitinib at a standard dose (50 mg daily, 4 wk on, 2 wk off) was titrated to patient tolerance.

RESULTS

One patient has achieved a near complete response, and two patients demonstrated partial responses. Two patients demonstrated germline defects suggesting a pseudo-hypoxic drive to the tumor whereas the third demonstrated immunohistochemical evidence of this phenomenon.

CONCLUSIONS

Sunitinib appears to be an active agent in this malignancy based on this limited cohort, with an understandable mechanism of action similar to that described in other hypoxia-driven tumors. A single arm phase 2 trial is underway.

Pediatric extraadrenal paraganglioma

BACKGROUND

Pediatric paraganglioma is rare and extraadrenal paraganglioma has not been characterized in children.

METHODS

The authors reviewed the medical records and pathology samples of children with extraadrenal paraganglioma treated at our institution between December 1978 and September 2000. Clinical presentation, treatment, and outcome were evaluated.

RESULTS

Eight patients (median age, 11.4 years) were identified, 4 were boys and none had a family history of paraganglioma or associated syndromes. Primary tumors arose in the retroperitoneum (n = 3), carotid body (n = 2), jugulotympanic ganglion (n = 1), cervical-paraspinal region (n = 1), and lung (n = 1). Extraadrenal paraganglioma had not been suspected at presentation in any patient. Of 5 patients who underwent gross total resection at the time of diagnosis, 4 remain disease free, 1 had microscopic residual tumor and died of disease. Three patients had initially unresectable disease, 2 are disease free after neoadjuvant therapy and delayed surgery, and 1 has persistent disease after tumor embolization and radiotherapy.

CONCLUSIONS

Pediatric extraadrenal paraganglioma occurs most commonly in the retroperitoneum and head and neck, and the diagnosis usually is not suspected at the time of presentation. Surgery is the mainstay of treatment, and outcome is good after gross total resection. Neoadjuvant therapy can facilitate complete resection of initially unresectable tumors.

Vagal paragangliomas

The management of vagal paragangliomas is extremely challenging. Treatment of these lesions must be tailored individually for each patient. The best treatment modality depends on the patient's age and health and the size and extent of the tumor. This article discusses clinical presentation, multicentric and malignant vagal paragangliomas, evaluation, embolization, surgical management, and special considerations in the management of vagal paragangliomas.