PATTERN OF PROSTATIC CARCINOMA METASTASES IN BONES DETECTED BY BONE SCANS USING TECHNITIUM 99m METHYL DIPHOSPHATE (TC 99m MDP) IMAGING TECHNIQUE

Objective: To determine the pattern of bone secondaries in prostatic carcinoma patients using Technitium 99m Methyl Diphosphate (TC 99m MDP) imaging technique. Design: Retrospective study. Setting: Ziauddin Hospital, Karachi from 1998 to 2004. Methods: The study included 135 subjects, which were divided into four groups according to age. Patients with biopsy proven prostate carcinoma under went total body bone scan in different positions, five anterior and five posterior views, skull, chest, pelvis, knee and foot for the evaluation of metastases at the time of diagnosis. Bone scans were interpreted by the nuclear medicine consultant as negative or positive for skeletal metastases, or as intermediate. Results: 135 subjects were analyzed. They were divided into four groups according to age. Group A comprised of 25 subjects of age 30 to 39 years. Out of them 18 were positive for bone secondaries. Group B comprised of 30 subjects from 40 to 49 years. Out of them 21 were positive for bone secondaries. Third group i.e. C comprised of 50 to 59 years of age. Out of 49 subjects 36 were positive for bone secondaries. Group D was from 60 years and above in which 31 subjects were analyzed. Out of them 23 were positive for bone secondaries. The most common site involved was dorsal vertebrae in which 44 (32%) secondaries were isolated. Shoulder joint 38 (28%) and sacroiliac joint 29 (21%) were the second and third most commonly affected areas respectively. Other sites involved were skull, sacrum, lumber vertebrae, ileum, mandible, femur, sternum, cervical vertebrae, iliac crest, scapula, hip joint, tibia and pelvis. Conclusion: This study focuses on pattern of prostate carcinoma metastases to various bony sites. Metastases are common in age group 50 to 59 years and above 60 years while the most common site involved is dorsal vertebrae followed by shoulder joint and sacroiliac joint.