NOTCH1 and carcinosarcoma: Among variants of unknown significance (VUS), two were identified in both carcinosarcoma and ILC samples with approximately 50% VAF, including NOTCH1 (c.6685G>A, p.V229M, VAF 60.6% carcinosarcoma, 48.1% lobular) and TSC1 (c.2647G>A, p.A883T, VAF 58.5% carcinosarcoma, 40.9% lobular).