Intercostal Neuralgia Caused by a Parosteal Lipoma of the Rib

Incidental imaging finding of chest wall mass

“…Occasionally, large parosteal lipomas cause symptomatic mass effect resulting in limited joint mobility and/or nerve deficits [4]. Although definitive treatment is complete excision, these benign tumors have no known risk of malignant transformation [4]. When found incidentally in an asymptomatic patient, a parosteal lipoma with characteristic imaging findings may be followed without biopsy.…”

“…They are indolent, usually asymptomatic masses, most often diaphyseal involving the femur (approximately one-third of cases), proximal radius, humerus, tibia, clavicle, or pelvis [2]. To our knowledge, only seven of the approximately 150 reported cases in the English literature have involved a rib [3][4][5][6][7][8].…”

“…When the fibro-osseous pedicle and cartilage cap predominate, the lesion can have an appearance similar to osteochondroma [3]. Histologically, the fat cells are identical to those in typical lipomas of soft tissue [3,4]. Cytogenetic analyses have shown the chromosomal translocations in soft tissue and parosteal lipomas are identical, suggesting a common histopathogenesis [10].…”

“…In their case series and review, Kapukaya et al reported local swelling and pain in 58 % of parosteal lipomas with a slow-growing, painless, and non-tender immobile mass being the typical presentation [1]. Occasionally, large parosteal lipomas cause symptomatic mass effect resulting in limited joint mobility and/or nerve deficits [4]. Although definitive treatment is complete excision, these benign tumors have no known risk of malignant transformation [4].…”

“…While characteristically attached by a sclerotic bony pedicle, this is not always present. A cartilaginous cap may be present [3,4,6,9]. When the fibro-osseous pedicle and cartilage cap predominate, the lesion can have an appearance similar to osteochondroma [3].…”