潘柏勳¹、魏子鈞^1,2、鍾孝仁^1,2、黃志賢^1,2

¹台北榮民總醫院 泌尿部；²國立陽明大學醫學院 泌尿學科 書田泌尿科學研究中心

Po-Hsun Pan¹, Tzu-Chun Wei^1,2, Hsiao-Jen Chung^1,2, William J. Huang^1,2

¹Department of Urology, Taipei Veterans General Hospital, Taipei, Taiwan

² Department of Urology, School of Medicine and Shu-Tien Urological Institute, National Yang-Ming University, Taipei, Taiwan

 

Bone metastases are common in advanced prostate cancer and most of them are osteoblastic lesions. However, osteolytic bone lesions combined with severe hypercalcemia in patient with metastatic prostate cancer are unusual. Here we presented one case and the following treatment.

A 64-year-old man with the history of hypertension, hyperlipidemia and renal stone but no operation history presented with back pain, poor appetite, nausea and body weight loss of six kilograms within 6 months. He was admitted to gastroenterology (GI) ward for surveillance of possible pancreatitis or pancreatic malignancy. Pancytopenia was noted, together with free calcium 13.4 mg/dL (normal range: 8.4-10.6) and lactic dehydrogenase (LDH) 667 U/L (normal <250). Besides, panendoscopy revealed gastric ulcer. In suspicion of multiple myeloma, serum albumin globulin ratio, IgG, IgA and IgM were all tested but within normal range. Hence, bone marrow biopsy was performed with the pathology reporting metastatic carcinoma of prostate origin. All tumor markers were normal except elevated PSA up to 625.5 ng/ml was noticed. Pelvis CT scan revealed enlarged lymph nodes at left internal iliac chain, several small nodular opacities at bilateral lower lung fields and diffuse osteolytic change at T and L spine, left border of sacrum with compression fractures over T7, 9, 11 and L1. Whole body bone scan also showed several foci of increased uptake at bilateral scapulae, sternum, T-spine, L-1, rib cage, left border of sacrum, left acetabulum and left proximal femur. Under the impression of metastatic prostate cancer with multiple metastasis, cT3aN1M1b+c, androgen deprivation therapy (ADT) with Degarelix 240 mg was given first followed by 80 mg monthly. Hypercalcemia was treated with Denosumab 120 mg with serum calcium decreased from 13.4 to 6.8 mg/dl, with the impression of suppressed osteoclastic activity followed with relatively more prominent osteoblastic effect. Oral calcium was supplied but the serum calcium was still low. Lactate dehydrogenase (LDH) was once decrease from 799 to 391 U/L after ADT, but increased again. At the meanwhile, serum alkaline phosphate (Alk-p) was increased from 184 to 738 U/L. At this moment, he decided to receive abiraterone 1000 mg per day according to LAITUDE trial, without oral steroid due to recent repeated gastric ulcer bleeding while admission at GI ward. However, Alk-p was still increased for several days upto 3719 U/L but then decreased to 114 U/L, with lactate dehydrogenase (LDH) also down to normal limit. PSA level follow-up every month after treatment reported improvement (625.5à31.62à 25.41à0.54à0.33 ng/ml). Pelvis CT scan also showed both bone lesion and lymphadenopathy in regression change.

Osteolytic bone metastatic lesion with pancytopenia and severe hypercalcemia are not frequently encountered in patients with prostate cancer. After ADT and Denosumab treatment, serum calcium was controlled together with oral calcium supplement but elevated Alk-p and LDH were noted. In the subgroup analysis of LATITUDE trial, these might be a good predictor for upfront abiraterone usage. Despite no combined oral steroid due to gastric ulcer concern, the serum potassium and sodium has been within normal range, still with significant PSA control.