以睪丸漿細胞瘤為表現之多發性骨髓瘤:意外的偶遇

楊哲學、林益聖、歐宴泉、黃立華、許兆畬、童敏哲

台中童綜合醫院 外科部 泌尿科

Multiple myeloma with initial testicular extramedullary plasmacytoma: An unexpected encounter

Che-Hsueh Yang, Yi-Sheng Lin, Yen-Chuan Ou, Li-Hua Huang, Chao-Yu Hsu, Min-Che Tung

Division of Urology, Department of Surgery

Tungs’ Taichung MetroHarbor Hospital, Taichung

Taiwan

Case: A male, 69-year-old underlined with hypertension and gout, was first encountered with persistent hydrocele for one month Previous to that, he just had his bilateral inguinal hernia repaired by Total Extraperitoneal (TEP) laparoscopic approach. Then, continuous right scrotal swelling with pain was observed, finally ending up with right hydrocele with tenderness. He had visited twice at emergent room and aspiration was done. Unfortunately, the symptoms and signs kept bothering him soon after the intervention. Except for physical complaints from right scrotum, no other abnormalities were told from other review of systems.

When he first visited to our clinics, right scrotum was measured to be more than 10 cm in diameter and tenderness on palpation. Lab data, such as complete blood count (white blood cell: 5600/uL, Hb: 13.2 g/dL, platelet: 217000/uL, differential count: Segment 70.8%, Lymphocyte:13.3%, Monocyte:7.2%, Eosinophil:8%, Basophil:0.7%), hemoglobin A1c (5.9%), liver function test (GOT: 39 IU/L, 36 IU/L), renal function test (Creatinine: 1.22 mg/dL, B.U.N.: 21 mg/dL), testosterone (4.04 ng/mL), and alpha-fetoprotein (<2 ng/mL) were all within the normal range. Urine examination showed negative of pyuria, neither hematuria. However, PSA (4.66 ng/ml) and CEA (5.64 ng/ml) were both at the elevated level. Digital rectal examination was felt with bilateral firm nature of prostate, and estimated weight about 25 g. Herein, the genitourinary malignancy was suspicious. Computed tomography (CT) was thereafter arranged, which demonstrated enlarged right testis about 9cm with irregular surface and heterogeneous enhancement of unknown nature, and tumor should be taken into consideration. Also, osteolytic bone lesions at both ribs were seen, and metastasis, fibrous dysplasia or other nature were all possible. Based on the suspicious malignancy, we decided to perform trans-rectal ultrasound guided biopsy (TRUS-Bx) and right radical orchiectomy.

Total 12 cores of TRUS-Bx were done, and all showed benign tissues. As for right testis, plasmacytoma was examined. In this way, we looked into serum (calcium: 9 mg/dL), Bence-Jones proten (negative), and free light chain (2 free Kappa chain), and it all showed no abnormal. In urine, it revealed alpha-1 globulin of 2.3 %, alpha-2 globulin of 2.5%, beta globulin of 21%, and gamma globulin of 17.1%. Furthermore, we investigated whole body bone scan, and it disclosed several spots of increased uptake at T2, T3, T4, left margin of T9, L5, right middle S-I joint, sacrum, sternum, left shoulder, and multiple ribs. Multiple bony metastases are impressed. Besides, increased uptakes were identified at right zygoma and maxillary region, favoring inflammatory or traumatic change. Bone marrow core biopsy was afterward performed, but only reactive bone marrow with no plasma cell myeloma.

Based on the testicular plasmacytoma, previous osteolytic lesions on whole body bone scan and CT, multiple myeloma was impressed, and therapies were started with oral lenalidomide 10 mg once daily with bortezomib-dexamethasone treatment. Concurrent RT was scheduled and performed at the same time.

Discussion: Testicular cancer, accounting for around 1% in male cancers, affects majorly among the age population from the second to forth decades in life. Among all components, germs cell origins occupy about 95% of them, and the rest is rare to be seen. Plasma cell neoplasms features neoplastic changes from single clone of plasma cells of hematopoiesis, most often but not specifically happened in bone marrow. Sites otherwise out of bone marrow are termed extramedullary plasmacytoma (EMP). Extremely rare occurrence, as low as 0.5%, in testicular cancer is made up of EMP under primary or secondary causes. Judgments of single or multiple EMP are crucial to make diagnosis of solitary plasmacytoma (single, SP) or multiple myeloma (multiple, MM), and this differentiation is essential to upcoming therapies. Radiation therapy (RT) is the therapy of choice for SP, but in contrary high-dose chemotherapy combined with autologous hematopoietic stem-cell transplantation. (ASCT) is the alpha for MM and only palliative roles of RT. Besides, of all kinds of myeloma, different therapeutics principles are applied to the asymptomatic smoldering myeloma and symptomatic MM.

Testicular EMP is extremely rare to be seen, and often serves as a sanctuary site. In this case we presented, he was first impressed solitary testis plasmacytoma by pathological proof of extramedullary monoclonal plasma cells with typical hematoxylin-eosin staining. M protein cannot be found in serum or urinary and normal bone marrow smear. Nevertheless, after comprehensive studies of whole body bone scan and previous osteolytic lesions on CT, his final diagnosis was made with MM. Dating back to pre-operative status, no clues from clinical symptoms and signs could be observed. No bone pain, neither anemia nor hypercalcemia on laboratory studies, and no abnormal renal function were identified. The only likely clues of osteolytic lesions at ribs, but can be postulated by other reasons. However, after the comprehensive assessment after pathological results, the diagnosis of MM made a whole new different page on his disease, from RT with surveillances to active systemic therapies. For what makes things worse is that judged from published literatures, this case very possibly presented with the worst scenario of MM in the first beginning. Thus, the delicate informed consents are important before the systemic therapies are loaded.