Current Cancer Therapy Reviews - Volume 12, Issue 3, 2016

Non-Melanoma Skin Cancer (NMSC) is the most common form of skin cancer. Common risk factors linked to the occurrence of NMSC are occupational exposure to chemicals, ultraviolet light exposure, immunosuppresion, human papillomavirus infection, artificial tanning, premalignant skin lesions and inherited skin conditions. The various clinical manifestations of NMSC depend on location and subtype. Management of NMSC includes pathology confirmation, staging and treatment. Retinoid and nicotinamide have been shown to be effective for the prevention of NMSC, primary treatments available for the treatment of NMSC are wide local excision, Mohs micrographic surgery (MMS), radiotherapy (RT), topical agents (5FU cream) and photodynamic therapy (PDT). The choice of definite treatment depends on many factors such as performance status and age of the patient, location and size of the tumor, etc.

Skin cancer is common. General practitioners, general surgeons, dermatologists, and plastic surgeons all play a role in the management of cutaneous malignancies. Because patients are in contact with their primary care physicians more frequently, primary care physicians are instrumental in early detection and non-surgical management. Additionally, patient survival is statistically improved when a dermatologist is involved in patient care. Significant overlap in scope of practice exists, particularly between plastic surgeons and dermatologists. Either specialty may perform wide local excision or Mohs microsurgery as the definitive surgical management for skin cancers. A review of reconstructive challenges by region may act as a guide for which cases may ultimately require the expertise of a reconstructive surgeon.

Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the commonest skin malignancies and if diagnosed early have a good prognosis. Conversely, metastatic disease is rarely associated with a very poor prognosis. Locally advanced BCC is also uncommon and may not be amendable to surgery, radiation therapy or photodynamic therapy. The activation of the hedgehog pathway occurs in 90% of BCCs and inhibition of this pathway with well tolerated oral agents has resulted in an important therapeutic option in some patients with locally advanced or metastatic BCC. In contrast, metastatic SCC tends to behave biologically more aggressively and cisplatin based chemotherapy has very limited efficacy.

Melanoma is a common aggressive skin cancer. Its numerous genetic mutations have become rich targets for systemic therapy with chemotherapy or immunotherapy. Surgery is the best initial treatment. Completion nodal dissection for sentinel node positive patients decrease regional occurrence but no survival benefit was found in a few studies. Radiotherapy (RT) is used as primary, adjuvant and palliative treatment. Specific scenarios with unknown primary, head and neck melanomas, and distant metastases are discussed. Systemic therapy includes molecular therapy based on diver mutation or immunotherapy. Treatment guidelines should be utilized by the multidisciplinary team to aid treatment decision making. Future improvement in outcome can only be achieved by enrollment of patient into clinical trials and therefore should be encouraged. Future research will be along the line of immunotherapy, target therapy, hyperthermia, nanoparticles, neutron, and radioisotope treatments.

Despite being widely used for cancer treatment, conventional chemotherapeutic regimens based on anti-cancer drugs possess significant drawbacks in discriminating between normal and cancer cells, leading to detrimental effects on healthy tissues. The development of nano-formulations encapsulating the chemotherapy drugs is highly expected to improve the anti-cancer activities with favorable pharmacokinetic profile and consequentially minimized side-effects. Several organic and inorganic nanoparticles have received tremendous attention as carriers of various anticancer drugs in pre-clinical and clinical settings. In this review, we discuss on the progress of formulating and investigating various nano-formulationsin treating different cancers, with an emphasis on in vivo studies utilizing the nanoparticles for carrying small molecular weight anti-cancer drugs and focusing on the biocompatibility, targeting capability, cellular uptake, and the tumor regression efficacy of those nano-formulations.