Cryotherapy protocols for metastatic breast cancer after failure of radical surgery

To retrospectively assess the effect of cryotherapy in patients with metastatic breast cancer (MBC) but without local recurrence after resection of the primary lesion, we divided 120 MBC patients into cryotherapy (91 patients) and chemotherapy (29 patients) groups. In the cryotherapy group, 37 patients with tumor recurrence received multiple cryoablations, while 54 patients received only a single cryoablation. Moreover, 62 cryotherapy-group patients underwent cryoablation immediately after the detection of metastases (timely cryotherapy); 35 patients received simultaneous immunotherapy (cryo-immunotherapy), and 29 patients underwent cryoablation in our hospital 3 months after receiving chemotherapy in other centers (chemo-cryotherapy and delayed cryotherapy). Overall survival (OS) after the diagnosis of MBC was assessed after a 10-year follow-up. The median OS was higher in the cryotherapy group (55 months) than in the chemotherapy group (27 months; P < 0.0001). In the cryotherapy group, longer median OS was associated with multiple (76 months) rather than single cryoablations (48 months; P = 0.0005) and with timely (67 months) rather than delayed cryoablation (48 months; P = 0.0012). The median OS was higher after cryo-immunotherapy (83 months) than after chemo-cryotherapy (48 months) or cryotherapy alone (43 months; P < 0.0001 for both). In conclusion, timely and multiple cryoablations, especially when combined with immunotherapy, offer significant advantages over chemotherapy in extending the OS of MBC patients.