Bone scintigraphy in testicular tumors

Purpose: Testicular tumors do not occur frequently. Primary treatment is su rgical, and radiotherapy and chemotherapy can play important roles in cases of metastatic disease. Bone scintigraphy is used largely for early detecti on of skeletal metastases from several tumors, and conventional radiographi c studies are less sensitive than the nuclear technique for such a purpose. The aim of this study was to identify the role of bone scintigraphy in cas es of testicular tumors, regardless of the grade. Materials and Methods: The authors examined 28 patients (8 to 52 years old) with proved testicular tumors using Tc-99m MDP (750 MBq; 20 mCi) injected intravenously. Whole-body images were obtained 2 hours later, at 500,000 co unts per image. Radiographic studies were obtained to investigate abnormal areas noted on scintigraphy. Results: The results of bone scintigraphy were abnormal in seven cases, con sisting of variable but diffuse uptake in the iliac bone on the same side a s the affected testicle. MDP uptake was substantial in five of these patien ts (four seminomas, one nonseminoma; only two radiographic studies were abn ormal), and the two other patients had moderate uptake of the radiopharmace utical (two seminomas; radiographic studies were normal). Metastases were c onfirmed by biopsy in three cases. Discussion: Early metastases from seminomas can occur through the lymphatic drainage toward the iliac lymph node chain. This could explain these findi ngs. The scintigraphic aspects of the affected iliac bones seem characteris tic. Conclusions: Early detection of metastases is very important to ensure the efficacy of radiotherapy and chemotherapy, Bone scintigraphy may play an im portant role in such cases and seems to be more sensitive than conventional radiography. Testicular tumor metastases should be considered when iliac i nvolvement is observed. Paget's disease should be included in a differentia l diagnosis.