A recently described subtype of renal cell carcinoma (RCC) bearing chromosome translocations involving a breakpoint at Xp11 and resulting in gene fusions involving the TFE3 transcription factor gene often presents in the pediatric population.
The recently recognized Xp11 translocation renal cell carcinomas (RCCs), all of which bear gene fusions involving the TFE3 transcription factor gene, comprise at least one-third of pediatric RCC.
Pathologists should pay attention to the afore-described unusual stromal reaction of adult-onset RCC associated with Xp11.2 translocations/TFE3 gene fusions.
The consistent immunohistochemical staining for TFE3 in all RCC with unusual histology, regardless of patient age, is likely to expand the spectrum of Xp11.2 translocation RCC with respect to age, clinical behavior, and molecular abnormalities.
A retrospective review was conducted to describe the clinical characteristics and outcome of adult patients with metastatic Xp11.2 RCC who had strong TFE3 nuclear immunostaining and received anti-VEGF therapy.
We created 2 tissue microarrays (TMA) containing five 1.4-mm cores from each of 21 Xp11 translocation RCC (all confirmed by TFE3 IHC, 6 further confirmed by genetics), 7 clear cell RCC (CCRCC), and 6 papillary RCC (PRCC).
Finally, pathologists should recognize that the histology of RCC associated with Xp11.2 translocation/TFE3 gene fusion may focally resemble that of chromophobe RCC, but TFE3 immunohistochemistry and molecular genetic study may be helpful in the differential diagnosis.
Recent studies suggest that renal cell carcinomas (RCCs) associated with the newly recognized Xp11.2 translocation (transcription factor E3 [TFE3] gene fusions) can be found among adults with RCC showing a very aggressive disease-course.
We selected 54 patients with renal cell carcinoma with positive nuclear transcription factor E3 and transcription factor EB expression from the Juvenile RCC Network.
CK7 and α-methylacyl coenzyme A racemase are sensitive markers for papillary RCC; TFE3 expression is essential in confirming the diagnosis of Xp11 translocation RCC.
Since TFE3 is implicated in RCC, we hypothesized that elevated GPNMB expression was due to increased TFE3 activity resulting from the inactivation of FLCN.