A large subset of RCC cases with tubulocystic and associated dedifferentiated collecting duct carcinoma-like areas ("tubulocystic carcinoma with poorly differentiated foci," similar to those shown in Figure 5, A and B) have been demonstrated to show somatic FH deficiency, and some cases have been confirmed to be associated with HLRCC.
Tubulocystic carcinoma of the kidney with poorly differentiated foci: a frequent morphologic pattern of fumarate hydratase-deficient renal cell carcinoma.
Tubulocystic carcinoma is one of subtypes of kidney cancer, but it is a rare structure in kidney cancer .
Based on these findings, we made a conclusive diagnosis of tubulocystic carcinoma of the bile duct.
The usual histopathologic pattern of CDC is that of a tubulopapillary or tubulocystic carcinoma
within a desmoplastic stroma that often contains neutrophils [14-17].
of the kidney: Clinicopathological analysis of 31 cases of a distinctive rare subtype of renal cell carcinoma.
, mucinous tubular and spindle cell carcinoma, and other recently described rare renal tumors.
Renal neoplasm with eosinophilic cells should also enter the differential diagnosis, which includes entities such as oncocytoma, chromophobe RCC, tubulocystic carcinoma
, unclassified RCC with rhabdoid differentiation, and MiT family translocation RCC.
(33) However, subsequently it has been demonstrated that tubulocystic carcinoma
and collecting duct carcinoma are distinct entities molecularly.
of the kidney is a well-circumscribed tumor with pure tubular and cystic growth patterns, cysts and tubules lined by a single layer of atypical cells with abundant eosinophilic cytoplasm and a variable hobnail appearance, and stromal desmoplasia (Figure 9).
([dagger]) Tubulocystic carcinoma
is a distinct low-grade variant of renal cell carcinoma that was not listed in the 2004 WHO classification.
(63) It is now recognized that AMACR can show positivity in tumors from many different organs and in several different types of renal tumors, including most MiTF/TFE family translocation carcinomas, tubulocystic carcinomas
, some collecting duct carcinomas, most mucinous tubular and spindle cell carcinomas, most acquired cystic disease-associated renal cell carcinomas, and some high-grade urothelial carcinomas of the renal pelvis.