In 3 cases, treatment was applied for less than a month because the patient deceased (non-melanoma skin cancer with a double CDKN2A nonsense mutation, therapy: palbociclib) or experienced severe side effects after initial drug application (CNS with non-V600E BRAF and NRAS mutation, therapy: dabrafenib plus trametinib; TSC2-mutated neuroendocrine carcinoma, therapy: everolimus). The gene discussed is CDKN2A; the disease is melanoma.