MANOVA analysis shows that the same VOCs, previously identified by GC-MS analysis (Fig. 2 and Table 2), discriminate also the cancer cells between long (major than 48 h) and short (less or equal to 48 h) CDT (p = 5 × 10−4), ER positive from ER negative (p = 3.5 × 10−5), PgR positive from PgR negative (p = 7.4 × 10−4) and HER2 overexpressing cells (p = 0.03) (Table 4). The gene discussed is ESR1; the disease is cancer.