<qa>  What type of cancer is invasive?Patients over 18 years Patient with HR , HER2- and node-positive proven by cytology invasive ductal carcinoma breast cancer, grade SBR II or III, and having an axillary dissection programmed, Or patient having cutaneous melanoma scheduled for a lymph node dissection at the Institut Curie including dissection of the lymph nodes draining the tumor, Voluntary having signed and dated written informed consents prior to any specific study procedure, 