RÉSUMÉ
Ocular perivascular epithelioid cell tumor (PEComa) is exceedingly rare. We reported two examples involving the choroid and subconjunctival tissue, respectively, in patients aged 17 and 20 years. Both tumors comprised packets and sheets of large polygonal cells with moderately pleomorphic nuclei and prominent nucleoli, traversed by delicate fibrovascular septa. Melanin pigmentation was present in one case. The tumors showed HMB45 and TFE3 immunoreactivity. TFE3 gene translocation was confirmed by FISH break-apart probes. RNA seq revealed PRCC-TFE3 and NONO-TFE3 fusions, with the former representing the first description of PRCC-TFE3 in PEComa. Critical reappraisal of the reported cases showed that ocular PEComa frequently affected young patents with melanin pigmentation, frequent TFE3 protein expression, and/or TFE3 gene translocation. No recurrence or metastasis was reported after complete excision despite the presence of cytologic atypia.
Sujet(s)
Facteurs de transcription à motifs basiques hélice-boucle-hélice et à glissière à leucines/génétique , Marqueurs biologiques tumoraux/génétique , Protéines du cycle cellulaire/génétique , Tumeurs de la choroïde/génétique , Tumeurs de l'oeil/génétique , Fusion de gènes , Maladies de l'appareil lacrymal/génétique , Protéines tumorales/génétique , Tumeurs des cellules épithélioïdes périvasculaires/génétique , Adolescent , Marqueurs biologiques tumoraux/analyse , Tumeurs de la choroïde/composition chimique , Tumeurs de la choroïde/anatomopathologie , Tumeurs de la choroïde/chirurgie , Tumeurs de l'oeil/composition chimique , Tumeurs de l'oeil/anatomopathologie , Tumeurs de l'oeil/chirurgie , Femelle , Humains , Immunohistochimie , Hybridation fluorescente in situ , Maladies de l'appareil lacrymal/métabolisme , Maladies de l'appareil lacrymal/anatomopathologie , Maladies de l'appareil lacrymal/chirurgie , Mâle , Mélanines/analyse , Tumeurs des cellules épithélioïdes périvasculaires/composition chimique , Tumeurs des cellules épithélioïdes périvasculaires/anatomopathologie , Tumeurs des cellules épithélioïdes périvasculaires/chirurgie , RNA-Seq , Jeune adulteRÉSUMÉ
Primary liver carcinomas with both hepatocytic and cholangiocytic differentiation have been referred to as "combined (or mixed) hepatocellular-cholangiocarcinoma." These tumors, although described over 100 years ago, have attracted greater attention recently because of interest in possible stem cell origin and perhaps because of greater frequency and clinical recognition. Currently, because of a lack of common terminology in the literature, effective treatment and predictable outcome data have been challenging to accrue. This article represents a consensus document from an international community of pathologists, radiologists, and clinicians who have studied and reported on these tumors and recommends a working terminology for diagnostic and research approaches for further study and evaluation. CONCLUSION: It is recommended that diagnosis is based on routine histopathology with hematoxylin and eosin (H&E); immunostains are supportive, but not essential for diagnosis. (Hepatology 2018;68:113-126).