Endocrine Abstracts

Introduction: Brown tumor is a rare expansile osteolytic lesions benign bone lesion that arises as a direct result of parathyroid hormone on bony tissue in some patients with hyperparathyroidism. The reported prevalence of the brown tumour is 0.1% Brown tumor as the only and initial symptom of normocalcemic primary hyperparathyroidism is a rare clinical entity. Here, we present a case with multiple brown tumors in a young normocalcemic woman as a sequele of primary hyperparathyroidism mimicking bone metastases

Case report: 44 year old female diabetic, hypertensive and hypothyroid presented by painless swelling over the lumbo-sacral region gradually increased in size not related to trauma. PAN-CT: large infiltrative heterogenous soft tissue mass at the sacrum (19.8×19.5×12.3 cm) serum calcium, phosphate and alkaline phosphatase, PTH were normal. Biopsy taken showed: numerous osteoclast-like multinucleated giant cells follow up of the mass size was advised every 3 – 6 months The patient developed anemic manifestation (Hb= 5 g/dl), for which She received blood transfusion 3 times and referred to our hospital for further assessment

Examination: She was depressed, BP:170/80, pulse:103 /mint, Temp: 37 C, pallor, Bilateral lower limb edema A mass felt occupying right iliac, suprapubic, left iliac fossae, large oval Lumbo-sacral swelling 19×10 cm, normal neurological examination HB 7.6 g/dl, MCV 90 fl, Platelet 351 U/l, TLC 6.4 U/l, creatinine 1.39 mg/dl, calcium 9 mg/dl, phosphrous 4.3 mg/dl, PTH 199.7 pg/ml (10-55) Abdominal and pelivc sonar showed, pelvi- abdominal mass with multiple cystic areas (23.3×15 cm) Kidneys: Bilateral Moderate Back pressure with bilateral Hydroureter 19×11 cm. 99 mTc Sestamibi parathyroid scan showed intense radiotracer uptake in the left upper neck (parathyroid adenoma), uptake in the sacrum (?brown tumor) Surgical removal of sacral mass was not applicable Left parathyroidectomy was done biopsy reported parathyroid adenoma Follow up after 3 years: normal serum PTH level, marked decrease in mass size (6.2×5.2×3.3 cm)

Conclusions: Brown tumors are extremely rare in normocalcemic primary hyperparathyroidism, accurate diagnosis enables the proper treatment