Objective:

To investigate the imaging features of renal carcinomas associated with Xp11.2 translocation/

TFE

3 gene fusions (Xp11.2/TFE RCC).

Methods:

The imaging data of 14 patients with Xp11.2/

TFE

RCC confirmed by operation and biopsy were analyzed retrospectively. Image analysis included maximum size location

morphology

density or signal intensity and o

verall homogeneity on plain scan images

enhancement degree

enhancement pattern

presence of pseudocapsule

lymph node and distant metastasis.

Results:

There were 14 lesions. The ratio of male to female was 4∶10. CT found 9 lesions

and MRI found 5 lesions. The size of lesions was 1.8-11.8 cm. There were 9 lesions (64.3%) with round or oval shape

and 5 lesions (35.7%) had irregular shape. Inhomogeneous density or signal intensity was observed in 12 lesions (85.7%)

and other 2 lesions (14.3%) had homogeneous density or signal intensity. Hemorrhage

necrosis or cystic degeneration was observed in 10 (71.4%)

8 (57.1%) lesions. Inhomogeneous enhancement pattern was shown in 13 lesions (92.8%). In 11 lesions (78.6%)

the enhancement degree was lower than that of the renal cortex but higher than that of the renal medulla on arterial phase

but in other 3 lesions (21.4%)

the enhancement degree was lower than that of the renal cortex and renal medulla. The pseudocapsule was displayed in all 5 lesions found by MRI. Retroperitoneal lymph node and liver metastasis occurred in one case.

Conclusion:

The CT/MRI features of Xp11.2/

TFE

RCC are often characterized by the masses with moderated blood supply

heterogeneity

pseudocapsule

and more frequency in females.