Focal hematopoietic hyperplasia of the rib—A form of pseudo-tumor. Case report and review of articles

INTRODUCTION: Focal hematopoietic hyperplasia (FHH) is an unusual benign lesion that can rarely involve the ribs. In general, FHHs is a tumor-like expansion of ribs due to the abnormal proliferation of bone marrow. FHHs are mostly found incidentally at radiologic studies performed for other reasons. They are characterized by gradually enlarging osteolytic masses that involve the rib. PRESENTATION OF CASE: Here, we present an unusual case of focal hematopoietic hyperplasia of the rib who arrived to our institute with a complaint of severing back pain at the level of T5-T6 vertebrae. The diagnosis of FHH has been made based on clinical and radiologic findings and confirmed by histopathologic evaluations. We also reviewed all previously reported cases of Focal Hematopoietic hyperplasia of the rib in the literature. DISCUSSION: None of the previously reported cases, same as our patient, gave a history of trauma to the site involved or family history of malignancy. There was no association with hematological disorders or other malignancies that might have initiated FHH. Histologic evaluations of previously reported cases represented a hyper cellular bone marrow merging with the fatty marrow. The morphology and maturation of all hematopoietic cell lines were normal and there was no report of morphologically abnormal hematopoietic cell or malignant tumor cells. CONCLUSION: Physicians must consider the FHH among differential diagnosis of secondary rib lesions. Surgical resection is the treatment of choice; the risk of recurrence or metastasis is neglectable.