Discussion
Glucagonoma syndrome (GS) is a rare paraneoplastic phenomenon. Its most common features are weight loss, NME and diabetes mellitus (3).NME is considered a hallmark clinical sign of glucagonoma syndrome, present in approximately 70% of patients (3).The dermatosis evolves in 7–14 days, occurring in spontaneous exacerbations and remissions(4). Cutaneous features can mimic bullous dermatitis; it may also present as psoriasiform or eczematous plaques(5). Our patient’s cutaneous lesion were under recognized and we misinterpreted the skin manifestations as more common entities such as prurigo, eczema, and drug eruption for six years. The polymorphism of the cutaneous features and the rarety of glucagonoma delayed the recognition of the clinical syndrome. There are many reports of delayed diagnosis of glucagonoma due to misdiagnosis or delayed diagnosis of skin lesions(6–11). The average time from recognized symptoms to diagnosis is about four years (12). Histology may show non specific dermatitis, requiring multiple biopsies to confirm the diagnosis. The most specific feature includes superficial epithelial necrosis of the upper spinous layer with vacuolated keratinocytes. Lack of specific findings on biopsy and the rarity of the pancreatic tumor can attribute to delays in diagnosis(4).
NME is a valuable cutaneous presentation in this diseases, when the skin lesions relapsed, we were convinced of the recurrence of the tumour even though the scan was normal.
By the time of diagnosis, 50-100% of patients already present with metastatic disease, and a cure is often impossible(2). However, since this islet cell tumor is slow-growing, prolonged survival (more than 20 years) is possible, and in metastatic disease, most causes of death appear to be unrelated to the tumor(13). Causes of death are correlated to thromboembolism, sepsis, and gastrointestinal bleeding (14).Skin changes appear early in the course of GS and are reason for seeking medical help for the first time. They are followed by systemic symptoms such as weight loss, diarrhea, diabetes mellitus, neuropsychiatric disorders, anemia, and thrombosis.
Diabetes mellitus is found in 80% of patients with the GS (3). Our patient had no diabetes and this delayed the recognition of the clinical syndrome.
Glucagonoma syndrome is associated with a high incidence of thromboembolism, estimated between 10 and 30% of patients (15) which is responsible for the immediate cause of death in up to 50% of patients (16). Our patient was diagnosed with deep vein thrombosis in the leg.
Complete resection of the tumor is the best treatment. Our patient’s cutaneous lesions vanished one week after surgery. Patients who underwent resection had longer median survival than patients who did not receive surgery, even when diagnosed with later stages of disease(17).