Unusual late metastasis from gastric carcinoma.

Sir,

Bone metastases from stomach cancer relates closely to poorly differentiated adenocarcinoma and has a tendency to occur in people with high lymph node involvement. Recurrence more that 8 years after surgery is extremely rare.[12] Here, we present a case of bone metastasis occurring after 8 years of surgery.

A 68-year-old woman was admitted with a 4-month history of diffuse lower back pain and weight loss. Eight years ago, she was diagnosed as having gastric adenocarcinoma poorly differentiated with areas of signet ring cell carcinoma [Figure 1a]. Twenty-six lymph nodes were examined, of which 16 were found metastatic; she then underwent total gastrectomy, but no complementary chemotherapy was administered. She was under surveillance for 8 years, which includes abdominal ultrasound, chest X-ray, blood count, liver function test; tumor markers [carcinoembryonic antigen (CEA), Ca 19.9] were normal, with apparent remission.

Figure 1

(a) Histology of primary tumor showing poorly differentiated adenocarcinoma with signet ring cells, and (b) bone marrow biopsy showing poorly differentiated adenocarcinoma with signet ring cells

Physical examination yielded normal results. Laboratory studies showed the following findings: Hb 9 g/dl; white blood cell count, 6,500/μL; platelets, 87,000 μ/L; lactate dehydrogenase (LDH), 578 U/L; alkaline phosphatase, 1,350 U/L; CEA, 7.1 ng/mL; and Ca 19.9, 1,580 U/ml.

Computed tomography (CT) scan of the chest and abdomen, and lumbar magnetic resonance imaging (MRI) showed multiple mixed osteolytic-osteoblastic lesion on the lumbar spine and pelvis without evidence of extra-osseous metastasis. Transiliac bone biopsy revealed an infiltrating adenocarcinoma poorly differentiated with signet ring cell [Figure 1b].

The outcome was unfavorable, chemotherapy was discarded, and the patient died 2 months after diagnosis.

Metastasis to the bone from gastric tumors is rare and has been estimated to appear in 1.2%-13.4% of the cases. The difference depends on whether the observation were clinical or at autopsy,[34] and are a late complication occurring years after total removal of primary tumor. These are usually osteolytic or, less commonly, mixed osteolytic–osteoclastic; diffuse osteoblastic lesion may be an unusual feature of this tumor. Thoracic and lumbar vertebrae are the most frequent sites of bone metastases.[4]

Main symptoms of metastasis are pain (70%), fractures (8.5%), and paraplegia (8.5), but 21% of the cases are asymptomatic.[3] Laboratory tests showed normocytic, normochromic anemia, thrombocytopenia, and increased levels of serum alkaline phosphatase and Ca 19.9. Bone marrow aspiration and biopsy provide the evidence of malignancy.[14]

Prognosis of patients with osseous metastasis is not good and the median survival time is about 5 months after appearance of symptoms. Radiotherapy has been advocated as the best therapeutic alternative for pain control, with a response rate of 75%, and chemotherapy with 5-fluorouracil (5-FU) have been employed. Nevertheless, prognosis remains poor and therapy is mainly aimed at relieving pain and discomfort.[4]