Doege-Potter Syndrome with a Benign Solitary Fibrous Tumor: A Case Report and Literature Review

Abstract

Doege-Potter syndrome is a rare paraneoplastic syndrome that is often diagnosed incidentally during the workup of hypoglycemia of unclear etiology. It is characterized by a non-islet cell tumor hypoglycemia secondary to excessive production of partially processed IGF-II hormone from a solitary fibrous tumor (SFT). Often these tumors are intrathoracic, benign, and asymptomatic. Occasionally they present as a paraneoplastic event; hypertrophic osteoarthropathy in Pierre-Marie-Bamberger syndrome and hypoglycemia in Doege-Potter syndrome. The NAB2-STAT6 gene fusion is the hallmark of the SFT. Complete surgical resection of the tumor often results in resolution of symptoms and cure in most cases. Here we present the case of an 83-year-old non-diabetic female with recurrent syncopal events who was diagnosed with the Doege-Potter syndrome secondary to a SFT of pleura. Her tumor was positive for NAB2-STAT6 gene fusion on RT-PCR. Following the resection of the giant tumor mass, she became symptom-free within 24 h, and has remained asymptomatic at 4 months follow-up.

Keywords: Doege-Potter syndrome; Insulin-like growth factor II; NAB2-STAT6; Non-islet cell tumor hypoglycemia; Solitary fibrous tumor.

Fig. 1

A Coronal section of the CT chest showing right lower lobe mass abutting adjacent lung, mediastinum and diaphragm below. B Gross appearance of the mass (>15 cm) post resection.

Fig. 2

A Low power showing well-circumscribed, encapsulated proliferation of spindle cells with staghorn vascularity (thick arrow) and areas of hyaline degeneration (thin arrow) but no necrosis. B Staghorn vessels with spindle cells showing mild to moderate nuclear atypia. C Up to 4 mitoses per high-power field. D Strong and diffuse nuclear positivity for STAT6.

Fig. 3

A Immunostaining for STAT-6 showing strong and diffuse nuclear reactivity. B Immunostaining for CD34 was strongly positive. C TLE-1 showing weak non-specific staining.