Differential Diagnosis

• Single most likely diagnosis
  • C) Metastatic prostate carcinoma: This is the most likely diagnosis given the patient's age, sex, and the presence of osteoblastic lesions in the vertebrae. Prostate cancer is known to metastasize to bones, often causing osteoblastic lesions, and the locations mentioned (T11, T12, L1, and L2) are common sites for metastasis.
• Other Likely diagnoses
  • D) Multiple myeloma: Although multiple myeloma typically presents with osteolytic lesions, it can occasionally present with osteoblastic or mixed lesions. The back pain and vertebral involvement could fit this diagnosis, but it's less likely than metastatic prostate carcinoma given the osteoblastic nature of the lesions.
• Do Not Miss
  • A) Abdominal aneurysm: While less likely given the osteoblastic lesions, an abdominal aortic aneurysm could cause back pain and tenderness, especially if it's expanding or leaking. This condition is life-threatening and requires immediate attention, making it a "do not miss" diagnosis.
• Rare diagnoses
  • B) Fibrosarcoma: This is a rare type of cancer that could potentially cause bone lesions, but it's much less common than metastatic disease from prostate cancer or other primary bone malignancies like multiple myeloma.
  • E) Osteosarcoma: Osteosarcoma is a rare primary bone cancer that can cause osteoblastic lesions, but it's more commonly seen in younger patients and is less likely in a 72-year-old man without other risk factors (like previous radiation exposure or Paget's disease).