Bone Metastases from Gastric Cancer Resembling Paget's Disease: A Case Report.

Systemic osteosclerotic lesions are frequently caused by multiple bone metastases or systemic metabolic disorders. However, bone metastasis from gastric cancer is rare. Herein, we describe such a case, with radiographic and clinical findings resembling Paget's disease. The patient was an 80-year-old Japanese woman with a history of early gastric cancer, treated by partial gastrectomy 2 years prior. The patient sought medical care for chronic low back pain. On imaging, systemic sclerotic lesions were observed throughout the spine and pelvis, with an increase in bone mineral density from 0.86 g/cm3 (2 years prior) to 1.38g/cm3 (current visit) in the lumbar spine. Elevated serum levels of osteoblastic and osteolytic markers were identified. A bone biopsy was used to confirm the diagnosis of metastatic gastric cancer. The patient was treated with TS-1 and denosumab, with normalization of abnormal metabolic markers and alleviation of the back pain. Bone metastasis is reported in only 10% of cases of gastric cancer and, thus, is relatively rare. Therefore, our case of gastric cancer recurrence presenting with mixed osteoblastic and osteolytic bone lesions similar to Paget's disease is relevant to the report. Bone biopsy is necessary for an accurate diagnosis.

Subtrochanteric fracture in a patient receiving zoledronic acid therapy for metastatic breast cancer.

A 61-year-old woman presented with acute pain of the right thigh after falling on a public street. She had been diagnosed with metastatic breast cancer and bisphosphonate therapy along with zoledronic acid. Radiographs demonstrated transverse subtrochanteric femoral fracture with thickening of the lateral cortex and spike of the medial cortex at the site of fracture. The contralateral femur showed thickening of the lateral cortex at the same site. This type of stress fracture is related to severe suppression of bone turnover (SSBT) under bisphosphonate therapy. Our patient had been receiving zoledronic acid therapy for 3.6 years, and the radiographic findings were typical of stress fracture associated with bisphosphonate. Therefore, the facture in our patient was considered related to SSBT under zoledronic acid therapy. Zoledronic acid is administered to patients with osteoporosis or complications due to cancer such as hypercalcemia of malignancy. Recently stress fractures associated with zoledronic acid therapy for osteoporosis have attracted attention. However, there are few reports of fracture associated with zoledronic acid therapy for cancer. Doses of zoledronic acid recommended for cancer patients are much greater than those for patients with osteoporosis. Clinicians treating such cancer patients need to cautiously manage stress fractures as a complication of zoledronic acid therapy.

Influence of aging on the carcinogen-induced protein kinase activity in rat liver cell nuclei.

A carcinogen-induced increase in a protein kinase activity was found in cell nuclei of rat liver. The enzyme was extracted from isolated nuclei with a hypotonic buffer, retained to an anion-exchange column, eluted with 0.15 M NaCl containing solution and to be measured for the activity with casein as the substrate, showing a nature of a casein kinase. The change in the activity during the course of aging was studied with 5-, 10-, and 50-week old Wistar male rats. The activity was highest in 5-week-old rat but decreased in 10- and 50-week-old animal. A hepatocarcinogen, thioacetamide, induced an increase in activity in 10-week old rats but rather decreased in 5- and 50-week-old rats. Aging suppresses the activity of this unique enzyme. Thioacetamide abolishes this suppression resulting in an increase in the activity of the enzyme at a certain stage of aging.