P-19 A case of Birt Hogg Dube syndrome presented with parathyroid carcinoma

Abstract

Abstract Introduction The Birt Hogg Dube syndrome is an autosomal dominant genodermatosis caused by a mutation in the folliculin gene. It is characterized by benign lung cysts with spontaneous pneumothorax, kidney tumors, and hair follicle tumors. Other solid tumors may accompany. Our case is a man with Birt Hogg Dube Syndrome who has parathyroid cancer. Clinical Case A 50-year-old male was referred to our clinic for treatment of hypercalcemia and elevated parathormone; he complained of weakness, muscle, and joint discomfort. His previous medical history included Renal Cell Carcinoma, Coronary artery by-pass graft, pulmonary thromboembolism, hypertension, nephrolithiasis, and stage 4 chronic kidney disease. There was a familial history of colon cancer, with both his aunt and uncle having been diagnosed. The systemic evaluation revealed the presence of constipation, polyuria, pollakiuria. A palpable 3 cm nodular lesion was discovered in the inferior lobe of the patient's left thyroid, and the patient's vital signs were stable. There were lesions on the inner surface of the right thigh and the skull. The biopsies obtained from the lesions on the skin revealed a lipoma on the cranium and a fibrofolliculoma on the thigh upon pathological examination. Regarding laboratory exams, both the hemogram and transaminase levels were within normal limits. Serum albumin was measured at 4.9 g/L creatinine at 2.5 mg/dl, calcium at 12 mg/dl, ionized calcium at 5.9 mg/dl, phosphorus at 2.4 mg/dl, parathormone at 373 ng/dL, and 25-OH Vitamin D at 32 ng/ml. Alkaline phosphatase was determined to be 66 U/L, and 24-hour calcium output was 60 mg/day. The thyroid function test results were euthyroid, while the anterior pituitary panel was normal. The patient underwent a left inferior parathyroidectomy after thyroid ultrasonography and parathyroid scintigraphy revealed a parathyroid adenoma. The parathyroid carcinoma is identified in the pathology report. The ultrasound-observed nodule on the isthmus of the thyroid has been identified as thyroid papillary carcinoma. Bone mineral density was normal. A previously performed CT scan of the thorax for dyspnea revealed the presence of multiple cystic structures in the lungs. Taking into account the patient's history of multiple malignancies, an 18-FDG-PET CT scan was performed, revealing a significant FDG uptake (SUV Max: 22) in the patient's sigmoid colon. Pathology analysis of the removed lesion confirmed that it was a tubulovillous adenoma with high-grade dysplasia. The patient, who showed heterozygosity for the Folliculin gene, was identified as having Birt-Hogg-Dube syndrome after further genetic panel testing. Conclusion According to the most recent literature evaluation, our patient is the first Birt Hogg Dube individual to present with parathyroid carcinoma. There is some evidence in the published literature linking somatic mutation of the Folliculin gene to the development of parathyroid cancer.