Ano de Publicação: 2018
AUTORIA
Chisato Ohe;Steven Smith;Deepika Sirohi;Mukul Divatia;Mariza de
Peralta-Venturina;Gladell Paner;Abbas Agaimy;Mitual
Amin;Pedram Argani;Ying-Bei Chen;Liang Cheng;Maurizio
Colecchia;Eva Compérat;Isabela Werneck da Cunha;Jonathan
Epstein;Anthony Gill;Ondřej Hes;Michelle Hirsch;Wolfram
Jochum;Lakshmi Kunju;Fiona Maclean;Cristina Magi-Galluzzi;Jesse
McKenney;Rohit Mehra;Gabriella Nesi;Adeboye Osunkoya;Maria
Picken;Priya Rao;Victor Reuter;Paulo de Oliveira Salles;Luciana
Schultz;Satish Tickoo;Scott Tomlins;Kiril Trpkov;Mahul Amin;
RESUMO
Renal medullary carcinomas (RMCs) and collecting duct carcinomas
(CDCs) are rare subsets of lethal high-stage, high-grade distal
nephron-related adenocarcinomas with a predilection for the renal
medullary region. Recent findings have established an emerging
group of fumarate hydratase (FH)-deficient tumors related to
hereditary leiomyomatosis and renal cell carcinoma (HLRCC-RCCs)
syndrome within this morphologic spectrum. Recently developed,
reliable ancillary testing has enabled consistent separation
between these tumor types. Here, we present the clinicopathologic
features and differences in the morphologic patterns between RMC,
CDC, and FH-deficient RCC in consequence of these recent
developments. This study included a total of 100 cases classified
using contemporary criteria and ancillary tests. Thirty-three RMCs
(SMARCB1/INI1-deficient, hemoglobinopathy), 38 CDCs
(SMARCB1/INI1-retained), and 29 RCCs defined by the FH-deficient
phenotype (FH−/2SC+ or FH±/2SC+ with FH mutation, regardless of
HLRCC syndromic stigmata/history) were selected. The spectrum of
morphologic patterns was critically evaluated, and the differences
between the morphologic patterns present in the 3 groups were
analyzed statistically. Twenty-five percent of cases initially
diagnosed as CDC were reclassified as FH-deficient RCC on the
basis of our contemporary diagnostic approach. Among the
different overlapping morphologic patterns, sieve-like/cribriform
and reticular/yolk sac tumor–like patterns favored RMCs, whereas
intracystic papillary and tubulocystic patterns favored FH-deficient
RCC. The tubulopapillary pattern favored both CDCs and FHdeficient
RCCs, and the multinodular infiltrating papillary pattern
favored CDCs. Infiltrating glandular and solid sheets/cords/nested
patterns were not statistically different among the 3 groups. Viral
inclusion–like macronucleoli, considered as a hallmark of HLRCCRCCs,
were observed significantly more frequently in FH-deficient
RCCs. Despite the overlapping morphology found among these
clinically aggressive infiltrating high-grade adenocarcinomas of the
kidney, reproducible differences in morphology emerged between
these categories after rigorous characterization. Finally, we
recommend that definitive diagnosis of CDC should only be made if
RMC and FH-deficient RCC are excluded.