Correct classification before a pediatric liver-tumor discussion

A fictional child has a liver tumor for which the imaging report explicitly identifies involvement of both right hepatic sectors. The left lateral and left medial sectors are contiguous and entirely free of tumor. No extrahepatic disease, vascular annotation, histology or treatment response is supplied. A trainee calls the lesion PRETEXT III because two sectors are involved and there is one visible mass. The multidisciplinary supervisor asks the trainee to apply the actual sector framework rather than count masses or assume that every staging system uses the same arithmetic. The exercise concerns anatomical classification and what remains unknown. It does not assign chemotherapy, determine resectability from the category alone or claim that a correct category is the entire prognosis.