Case Presentation:
65 year old man with HTN, active tobacco and alcohol use presents with right (R) hip and knee pain for 4 months, worsening over the past 2 weeks. 3 months ago, he presented to an orthopedic clinic for progressive R hip pain without any history of trauma or injury. An MRI showed a destructive lytic lesion with bone marrow edema of the R femoral head and neck. Imaging raised concern for malignancy and he was given the presumed diagnosis of metastatic prostate cancer. Following a CT guided biopsy patient was referred to oncology. At that time, patient was admitted to the hospital for worsening R knee pain and swelling for 2 weeks described as 7/10 sharp, stabbing pain worse with movement. Vital signs abnormal only for tachycardia at 110. Labs showed no leukocytosis, mild anemia, mild elevation in transaminases 66/43, CRP 8.1, ESR 28. Exam revealed asymmetric edema of the right lower extremity with a warm, tender, non-scaly, erythematous maculopapular rash located on the inner thigh and anterior leg. DVT studies were negative. X-ray of the femur, knee, tibia and fibula exposed a previously non-displaced femoral neck fracture now displaced superior-laterally with evidence of a lytic destructive lesion in the inferior right pubic bone region. Review of recent CT abd/pelvis showed an ill-defined mass which demonstrated arterial phase enhancement with washout, compatible with HCC. Patient was treated with 5 days of clindamycin for cellulitis superimposed on chronic stasis dermatitis. He underwent a right femur open-reduction internal fixation. Biopsy of the femur lesion was diagnostic for metastatic HCC. Hepatitis panel was significant for positive HCV infection with genotype 1a. Patient was discharged to rehab and follow up with outpatient oncology.
Discussion:
The most common causes of bone metastasis are prostate, breast and lung cancer. HCC is an aggressive malignant tumor that occurs in the setting of cirrhosis, most commonly due to chronic viral infections and alcohol use, with less than 15% of HCC patients being diagnosed with extrahepatic metastasis. The most common sites of extrahepatic metastasis are lung, intraabdominal lymph nodes, bone and adrenal glands; bone being least common. Because bone metastasis from primary HCC is uncommon, there is a paucity of data in the medical literature on the subject. Bone metastasis appears to be unique amongst the hematogenous spread of HCC because patients often become symptomatic from the bone metastasis without clinical symptoms of liver disease, as seen with our patient. Bone lesions seen in metastatic HCC are usually hypervascular, osteolytic, and expansile. Skeletal metastasis is often treated with radiation; however, surgery is often indicated in cases of pathologic fractures of the femur or humerus or in cases where decompression is required.
Conclusions:
In patients with findings consistent with pathologic fractures, HCC should be considered as a possible diagnosis. Workup should include alcohol, drug use and sexual history, transfusion and transplant history.
