Age / Sex : 42 / F

Chief complaint : Incidental findings on APCT

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Courtesy : 윤영철 Young Cheol Yoon, 삼성서울병원 Samsung medical center Seoul hospital

Tuberous sclerosis complex

Discussion

Findings:
Multifocal sclerotic bone lesions in spine and pelvic bone.

Multiple AMLs in both kidneys.

Differential Diagnosis:

Osteoblastic metastasis, osteopoikilosis, POEM syndrome, and mastocytosis

Discussion:

Sclerotic bone lesions(SBL) were the third most common imaging finding in these patients after brain tubers and renal angiomyolipomas in tuberous sclerosis complex (TSC). If more than four SBLs were detected in a CT scan of any main body region, the differential-diagnosis of TSC has to be considered. Radiologically, the SBLs in TSC closely resemble bone islands (enostoses), foci of dense, compact bone within the medullary cavity of bones.

The differential diagnosis of sclerotic bone lesions includes osteoblastic metastasis, osteopoikilosis, POEM syndrome, and mastocytosis.

Several primary malignancies characteristically produce osteoblastic metastases, including carcinomas of the prostate gland, breast, and pancreas; mucinous adenocarcinoma of the gastrointestinal tract; transitional cell carcinoma; carcinoid tumor; lymphoma; medulloblastoma; and neuroblastoma. Of these malignancies, carcinomas of the prostate gland and breast most frequently result in osteoblastic metastases.

Osteopoikilosis is a disorder of endochondral ossification involving the secondary spongiosa. Multiple enostoses are laid down at the ends of short tubular bones; in the tarsal, carpal, and pelvic bones; and in the meta-epiphyseal regions of long bone.
 

Mastocytosis is an unusual systemic disease, with there is an abnormal proliferation and accumulation of mast cells. Bone lesions in mastocytosis may be lytic, blastic or mixed. Diffuse skeletal involvement is most frequent. Typically the radiographic pattern is an axial skeleton sclerosis and of the distal part of the long bones.

References:

Nilo A. Avila , Andrew J. Dwyer, Antoinette Rabel, Thomas Darling, Chien-Hui Hong, Joel Moss. CT of Sclerotic Bone Lesions: Imaging Features Differentiating Tuberous Sclerosis Complex with Lymphangioleiomyomatosis from Sporadic Lymphangioleiomymatosis. Radiology: Volume 254: Number 3—March 2010

Susanne Brakemeier, Lars Vogt, Lisa C. Adams et al. Sclerotic bone lesions as a potential imaging biomarker for the diagnosis of tuberous sclerosis Complex. Scientific reports 2018) 8:953

Lauren L. Ihde, Deborah M. Forrester,  Christopher J. Gottsegen et al. Sclerosing Bone Dysplasias: Review and Differentiation from Other Causes of Osteosclerosis. RadioGraphics 2011; 31:1865–1882

M.F. Ramos Solis, C. Gómez de la Heras, J. A. Luque Ordoñez et al. CT findings in systemic mastocytosis. ECR 2013/ C-0104