治疗费 is specifically the cost of medical treatment (procedures, medication, follow-ups). Compare with
医疗费 (yīliáofèi, 'medical expenses' — broader, including hospital stays, exams) and
医药费 (yīyàofèi, 'medical and drug fees'). When discussing crowdfunding for an illness,
治疗费 and
医药费 are the most common phrasings.