Colon adenocarcinoma and solitary tibia metastasis: rare entity

Isolated Skull Metastasis With Unusual Spiculated Periosteal Reaction From Rectal Cancer Resembling Osteosarcoma on FDG PET/CT

ABSTRACT

We describe FDG PET/CT findings in a case of isolated skull metastasis with spiculated periosteal reaction from rectal mucinous adenocarcinoma 8 years after proctectomy. The skull metastasis showed heterogeneous FDG uptake and multiple short spicules of bone producing the sunburst appearance resembling primary osteosarcoma or Ewing sarcoma. Familiarity with this atypical imaging appearance of the bone metastasis from rectal cancer may be helpful for the diagnosis and differential diagnosis.

Colorectal cancer with first known case of simultaneous bilateral tibial metastases

The most common osseous metastatic regions for colorectal cancer are the lumbar and sacral vertebrae and the pelvis. There are few reported cases of isolated solitary tibial metastasis, and simultaneous bilateral solitary tibial metastases in colorectal cancer are even rarer. A 62-year-old female patient was admitted to our inpatient clinic 3 years after receiving initial chemotherapy for a rectosigmoid adenocarcinoma with liver metastasis. The patient complained of left leg pain. Radiographs and magnetic resonance imaging revealed a 3- × 3-cm mass in the right proximal tibia and a 2- × 7-cm mass in the middle third of the left tibia; both were highly suggestive of bone metastases. Bilateral tibial metastases were confirmed after tumor excision and prophylactic open reduction and internal fixation. The postoperative course was relatively uneventful. Colorectal cancer with bone metastases is uncommon, and most metastases are found at a single site in an extremity. We believe this is the first published case of simultaneous bilateral tibial metastases in a patient with colorectal cancer.

Metachronous solitary metacarpal bone metastasis from rectal cancer

Metachronous solitary metacarpal bone metastasis from rectal cancer has not been reported previously. Here, we describe a 54-year-old woman who underwent abdominoperineal resection for rectal cancer following neoadjuvant chemoradiotherapy. The resected specimen contained adenocarcinoma with no lymph node metastases (Stage II, T3N0M0); no adjuvant chemotherapy was administered. Fifteen months after surgery, the patient presented with pain and swelling of the right thumb. Radiography revealed metacarpal bone destruction, and fluorine-18 fluorodeoxyglucose positron emission tomography showed uptake only in the metacarpal bone. Open biopsy revealed an adenocarcinoma, and a right thumb resection was performed. Histological examination indicated features of adenocarcinoma similar to the findings of a rectal lesion, leading to a diagnosis of metachronous solitary metacarpal bone metastasis from rectal cancer. The patient remains free of disease after 6 years of follow-up. Our findings suggest that surgical resection may lead to favorable outcomes in patients with resectable solitary bone metastases.

Colorectal cancer: Metastases to a single organ

Colorectal cancer (CRC) is a common malignancy worldwide. In CRC patients, metastases are the main cause of cancer-related mortality. In a group of metastatic CRC patients, the metastases are limited to a single site (solitary organ); the liver and lungs are the most commonly involved sites. When metastatic disease is limited to the liver and/or lungs, the resectability of the metastatic lesions will dictate the management approach and the outcome. Less commonly, the site of solitary organ CRC metastasis is the peritoneum. In these patients, cytoreduction followed by hyperthermic intraperitoneal chemotherapy may improve the outcome. Rarely, CRC involves other organs, such as the brain, bone, adrenals and spleen, as the only site of metastatic disease. There are limited data to guide clinical practice in these cases. Here, we have reviewed the disease characteristics, management approaches and prognosis based on the metastatic disease site in patients with CRC with metastases to a single organ.

Bilateral acrometastasis in a case renal cell carcinoma

We present a unique case of bilateral skeletal metastasis below the knee in a patient with renal cell carcinoma. In this rarest of rare cases, bony metastases were the first presentation of a primary tumour. Incidentally, the primary tumour (renal cell carcinoma) involved the solitary kidney of the patient and the same patient also had coexisting carcinoma of the prostate.