CNTs as Excellent Adjuvants for Anticancer Therapeutic Strategies and Cancer Diagnosis: A Plethora of Laboratory Studies versus Few Clinical Trials and Still No Clinical Application

Encouraging discoveries and excellent advances in the fight against cancer have led to innovative therapies such as photothermal therapy (PTT), photodynamic therapy (PDT), drug targeting (DT), gene therapy (GT), immunotherapy (IT) and therapies which combine these treatments with conventional chemotherapy (CT). Anyway, 2,041,910 new cancer cases and 618,120 cancer deaths have been estimated in the United States for the year 2025. The low survival rate (< 50%) and poor prognosis of several cancers, despite aggres-sive treatments, are due to therapy-induced secondary tumorigenesis and the emergence of drug resistance. Moreover, serious adverse effects and/or great pain, usually arise dur-ing treatments and/or in survived individuals, thus lower the overall effectiveness of these cures. Although prevention is of paramount importance, novel anticancer approaches are urgently needed to address these issues. In the field of anticancer nanomedicine, carbon nanotubes (CNTs) could be of exceptional help, due to their intrinsic unprecedented opti-cal, thermal, electronic, mechanic features, easy functionalization and large surface al-lowing excellent drug loading to serve as drug carriers, as well to engineer multifunctional platforms associable with diverse treatments for both anticancer therapy and diagnosis. The present review debates the most relevant advancements about the adjuvant role which CNTs could have in cancer diagnosis and therapy, when associated with PTT, PDT, DT, GT, CT and IT. Numerous sensing strategies utilizing CNTs-based electrochem-ical, colorimetric, plasmonic biosensors, as well as immunosensors for cancer diagnosis have been disserted in detail, never forgetting the still not fully clarified toxicological as-pects existing by their use in biomedicine. The unsolved challenges to be faced to make possible the translation of CNTs-based material in clinic have been discussed, to push scientists to focus on the development of advanced synthetic methods and purification work-up procedures, thus achieving more perfect CNTs for their safer real-life clinical use.