Osteoblastic Lesions as the First Presentation of a Gastric Mixed-Type Adenocarcinoma: A Case Report.

Bone metastasis might be associated with several tumors; however, the association between gastric malignant neoplasms and bone secondary lesions is very rare, with the osteoblastic form having the rarest presentation. In fact, osteoblastic lesions, as the first presentation of gastric adenocarcinomas, are even rarer and known to have a very poor prognosis associated with them. Therefore, we present a clinical case of a patient with lower back pain as the first symptom, which led to the diagnosis of osteoblastic lesions of the spine and iliac bones, suggested as secondary lesions. Later, the investigation of the primary tumor led to the diagnosis of a gastric adenocarcinoma (stage IV disease). In this report, we highlight the steps taken for the etiological study course and the challenges associated with them from the beginning. We also emphasize the very unfavorable evolution of our patient, with the inability to carry out targeted treatment, neither curative nor palliative, due to the advanced stage of the disease and the very poor survival time associated with it.