Contemporary approaches for imaging skeletal metastasis

The skeleton is a common site of cancer metastasis. Notably high incidences of bone lesions are found for breast, prostate, and renal carcinoma. Malignant bone tumors result in significant patient morbidity. Identification of these lesions is a critical step to accurately stratify patients, guide treatment course, monitor disease progression, and evaluate response to therapy. Diagnosis of cancer in the skeleton typically relies on indirect bone-targeted radiotracer uptake at sites of active bone remodeling. In this manuscript, we discuss established and emerging tools and techniques for detection of bone lesions, quantification of skeletal tumor burden, and current clinical challenges.

Skeletal muscle metastasis with bone metaplasia from colon cancer:A case report and review of the literature

BACKGROUND Colon cancer is a common malignant disease of the gastrointestinal tract and usually occurs at the junction of the rectum and sigmoid colon.Lymphatic and hematogenous metastases occur frequently in colon cancer and the most common metastatic sites include the liver,lung,peritoneum,bone,and lymph nodes.As a manifestation of advanced tumor spread and metastasis,soft tissue metastasis,especially skeletal muscle metastasis with bone metaplasia caused by colon cancer,is rare,accounting for less than 1%of metastases.CASE SUMMARY A 43-year-old male patient developed skeletal muscle metastasis with bone metaplasia of the right proximal thigh 5 mo after colon cancer was diagnosed.The patient was admitted to the hospital because of pain caused by a local mass on his right thigh.Positron emission tomography-computed tomography showed many enlarged lymph nodes around the abdominal aorta but no signs of lung or liver metastases.Color ultrasound revealed a mass located in the skeletal muscle and the results of histological biopsy revealed a poorly differentiated adenocarcinoma suspected to be distant metastases from colon cancer.Immunohistochemistry showed small woven bone components that were considered to be ossified.CONCLUSION This case reminds us that for patients with advanced colorectal tumors,we should be alert to the possibility of unconventional metastasis.

Skeletal muscle metastases of hepatocellular carcinoma: A case report and literature review

BACKGROUND The metastasis of liver cancer to skeletal muscle is extremely rare compared to other sites.We herein report a case of rapidly developing skeletal metastases following liver transplantation due to primary liver cancer.CASE SUMMARY A 70-year-old male with underlying chronic hepatitis B virus infection was diagnosed with hepatocellular carcinoma(HCC),for which he underwent liver transplantation in 2014.Six years after receiving the transplant,pathological examination confirmed the presence of HCC without vascular invasion.He was admitted to the hospital with a rapidly growing mass on his right thigh.Ultrasound examination revealed a mixed echo mass in the lateral soft tissue of the middle part of the right femur.Magnetic resonance imaging showed heterogeneous iso-signal intensity on T1-weighted images and heterogeneous hyper-intensity on T2-weighted images compared to the surrounding muscles.Pathological examination of the ultrasound-guided needle biopsy specimen revealed that it was similar to the previously detected liver cancer;the diagnosis was metastasis of HCC.Surgical excision was performed.There were no other sites of metastasis,and the patient recovered well after surgery.CONCLUSION This report presents a rare case of skeletal metastasis following liver transplantation for HCC.The study suggests a possible role for skeletal muscle metastasis mechanisms,which should be the focus of future research.