Reply to 'A phase II randomized controlled trial of nicotinamide for skin cancer chemoprevention in renal transplant recipients'

Oral Nicotinamide for Actinic Keratosis Prevention in Kidney Transplant Recipients: A Pilot Double-Blind, Randomized, Placebo-Controlled Trial

BACKGROUND

Oral nicotinamide (NAM) has shown promise in preventing actinic keratoses (AKs) in trials based outside of the United States. We assessed the efficacy of oral NAM supplementation in kidney transplant recipients with a history of keratinocyte carcinoma.

MATERIAL AND METHODS

Patients enrolled in a 2-week run-in phase, during which NAM 1000 mg was taken twice daily. After a washout period, patients who tolerated the run-in phase were randomized to NAM 500 mg twice daily or placebo. At baseline, 4, 8, and 12 months, dermatologists conducted full-body skin exams to document area-specific AKs. Routine lab work was collected to ensure the stability of renal allograft function.

RESULTS

The dosage was reduced from 1000 to 500 mg due to gastrointestinal symptoms in the run-in phase. Patients were randomized to NAM (n = 10) or placebo (n = 11). At 12 months, mean AK count was 30.8 (95% CI -11.7-73.4) for NAM and 26.6 (95% CI 10.8-42.5) for placebo. The difference in percent AK count change at 12 months compared with baseline was 259.8% (95% CI -385.9 to 905.5) for NAM and 72.4% (95% CI -118.6 to 263.5) for placebo. The between-group difference in percent AK change was not significant (P = .38). There was no attrition in the placebo group and 40% attrition in the NAM arm.

DISCUSSION

Nicotinamide did not decrease AK development among kidney transplant recipients. Limitations include drug tolerability, small sample size, and single-center trial nature.

Oral nicotinamide for non-melanoma skin cancers: A review

There has been much interest in the role of oral nicotinamide supplementation in reducing the incidence of non-melanoma skin cancers. This article reviews the hypothesised mechanisms of action of nicotinamide, and the available literature outlining its role for this purpose. There have been five randomised controlled trials (RCT), one histopathological study and two case series exploring the effect of oral nicotinamide supplementation on UV-induced immunosuppression of the skin, and incidence of actinic keratoses and non-melanoma skin cancers (NMSC). The largest RCT received criticism of the statistical analyses used, but the critics still acknowledged a likely benefit of treatment with oral nicotinamide in reducing the incidence of NMSC. Nicotinamide has a favourable safety profile. Current evidence is not definitive that oral nicotinamide supplementation reduces the incidence of NMSC, but it constitutes a low-risk management option that may be particularly relevant for high-risk individuals, and should be discussed as an option for these patients.

Nutrition and nonmelanoma skin cancers

Nonmelanoma skin cancer (NMSC), the most widely diagnosed cancer in the United States, is rising in incidence despite public health and educational campaigns that highlight the importance of sun avoidance. It is,therefore, important to establish other modifiable risk factors that may be contributing to this increase. There is a growing body of evidence in the literature suggesting certain nutrients may have protective or harmful effects on NMSC. We review the current literature on nutrition and its effect on NMSC with a focus on dietary fat, vitamin A, nicotinamide, folate, vitamin C, vitamin D, vitamin E, polyphenols, and selenium.

Keratinocyte Carcinoma and Photoprevention: The Protective Actions of Repurposed Pharmaceuticals, Phytochemicals and Vitamins

Simple Summary

Keratinocyte carcinoma is the most common type of cancer. Sun exposure and ultraviolet radiation are significant contributors to the development of carcinogenesis, mediated by DNA damage, increased oxidative stress, inflammation, immunosuppression and dysregulated signal transduction. Photoprevention involves using different compounds to delay or prevent ultraviolet radiation-induced skin cancer. In this review, we look at new avenues for systemic photoprevention that are based on pharmaceuticals, plant-derived phytochemicals and vitamins. We also investigate the mechanisms underlying these strategies for preventing the onset of carcinogenesis.

Abstract

Ultraviolet radiation (UVR) arising from sun exposure represents a major risk factor in the development of keratinocyte carcinomas (KCs). UVR exposure induces dysregulated signal transduction, oxidative stress, inflammation, immunosuppression and DNA damage, all of which promote the induction and development of photocarcinogenesis. Because the incidence of KCs is increasing, better prevention strategies are necessary. In the concept of photoprevention, protective compounds are administered either topically or systemically to prevent the effects of UVR and the development of skin cancer. In this review, we provide descriptions of the pathways underlying photocarcinogenesis and an overview of selected photoprotective compounds, such as repurposed pharmaceuticals, plant-derived phytochemicals and vitamins. We discuss the protective potential of these compounds and their effects in pre-clinical and human trials, summarising the mechanisms of action involved in preventing photocarcinogenesis.

European interdisciplinary guideline on invasive squamous cell carcinoma of the skin: Part 1. epidemiology, diagnostics and prevention

Invasive cutaneous squamous cell carcinoma (cSCC) is one of the most common cancers in the white populations, accounting for 20% of all cutaneous malignancies. Factors implicated in cSCC etiopathogenesis include ultraviolet radiation exposure and chronic photoaging, age, male sex, immunosuppression, smoking and genetic factors. A collaboration of multidisciplinary experts from the European Dermatology Forum (EDF), the European Association of Dermato-Oncology (EADO) and the European Organisation of Research and Treatment of Cancer (EORTC) was formed to update recommendations on cSCC classification, diagnosis, risk stratification, staging and prevention, based on current literature, staging systems and expert consensus. Common cSCCs are typically indolent tumors, and most have a good prognosis with 5-year cure rates of greater than 90%, and a low rate of metastases (<4%). Further risk stratification into low-risk or high-risk common primary cSCC is recommended based on proposed high-risk factors. Advanced cSCC is classified as locally advanced (lacSCC), and metastatic (mcSCC) including locoregional metastatic or distant metastatic cSCC. Current systems used for staging include the American Joint Committee on Cancer (AJCC) 8th edition, the Union for International Cancer Control (UICC) 8th edition, and Brigham and Women's Hospital (BWH) system. Physical examination for all cSCCs should include total body skin examination and clinical palpation of lymph nodes, especially of the draining basins. Radiologic imaging such as ultrasound of the regional lymph nodes, magnetic resonance imaging (MRI), computed tomography (CT), positron emission tomography-computed tomography (PET-CT) scans are recommended for staging of high-risk cSCC. Sentinel lymph node biopsy is currently not recommended. Nicotinamide, oral retinoids, and topical 5-FU have been used for the chemoprevention of subsequent cSCCs in high-risk patients but are not routinely recommended. Education about sun protection measures including reducing sun exposure, use of protective clothing, regular use of sunscreens and avoidance of artificial tanning, is recommended.

Management of skin cancer in recipients of solid organ transplants

Recent improvements in post-transplant care have led to an increased life expectancy for recipients of organ transplants. These patients require lifelong immunosuppression, which is associated with an increased incidence of malignant disease. Skin cancers are the most common malignancies seen in recipients of organ transplants and are associated with significant morbidity and mortality. This review describes factors pertaining to the development and prognosis of skin cancers in recipients of organ transplants, as well as outlining prevention and management strategies in this cohort.

Chemoprevention of Basal and Squamous Cell Carcinoma With a Single Course of Fluorouracil, 5%, Cream: A Randomized Clinical Trial

Importance

Keratinocyte carcinoma (ie, cutaneous basal and squamous cell carcinoma) is the most common cancer in the United States.

Objective

To determine whether topical fluorouracil could prevent surgically treated keratinocyte carcinoma.

Design, Setting, and Participants

The Veterans Affairs Keratinocyte Carcinoma Chemoprevention Trial was a randomized, double-blind, placebo-controlled trial of topical fluorouracil for chemoprevention of keratinocyte carcinoma. Participants were recruited from May 2009 to September 2011 from 12 Veterans Affairs medical centers and followed until June 30, 2013. Participants were veterans (n = 932) with a history of at least 2 keratinocyte carcinomas in the past 5 years; almost all were white males and the median age was 70 years.

Interventions

Application of fluorouracil, 5%, (n = 468) or vehicle control cream (n = 464) to the face and ears twice daily for 2 to 4 weeks upon randomization.

Main Outcomes and Measures

Surgically treated keratinocyte, basal cell, and squamous cell carcinoma risk on the face and ears in the first year after enrollment; and time to first surgically treated keratinocyte, basal cell, and squamous cell carcinoma. The a priori hypothesis was that fluorouracil would be effective in preventing these cancers.

Results

Of 932 participants (916 men [98%]; 926 white [99%]; median age, 70 years), 299 developed a basal cell carcinoma end point (95 in year 1) and 108 developed a squamous cell carcinoma end point (25 in year 1) over 4 years (median follow-up, 2.8 years). Over the entire study, there was no difference between treatment groups in time to first keratinocyte, basal cell, or squamous cell carcinoma. During the first year, however, 5 participants (1%) in the fluorouracil group developed a squamous cell carcinoma vs 20 (4%) in the control group, a 75% (95% CI, 35%-91%) risk reduction (P = .002). The 11% reduction in basal cell carcinoma risk during year 1 (45 [10%] in the fluorouracil group vs 50 [11%] in the control group) was not statistically significant (95% CI, 39% reduction to 31% increase), nor was there a significant effect on keratinocyte carcinoma risk. However, a reduction in keratinocyte carcinomas treated with Mohs surgery was observed.

Conclusions and Relevance

A conventional course of fluorouracil to the face and ears substantially reduces surgery for squamous cell carcinoma for 1 year without significantly affecting the corresponding risk for basal cell carcinoma.

Trial Registration

clinicaltrials.gov Identifier: NCT00847912.

Chemoprevention agents for melanoma: A path forward into phase 3 clinical trials

Recent progress in the treatment of advanced melanoma has led to unprecedented improvements in overall survival and, as these new melanoma treatments have been developed and deployed in the clinic, much has been learned about the natural history of the disease. Now is the time to apply that knowledge toward the design and clinical evaluation of new chemoprevention agents. Melanoma chemoprevention has the potential to reduce dramatically both the morbidity and the high costs associated with treating patients who have metastatic disease. In this work, scientific and clinical melanoma experts from the national Melanoma Prevention Working Group, composed of National Cancer Trials Network investigators, discuss research aimed at discovering and developing (or repurposing) drugs and natural products for the prevention of melanoma and propose an updated pipeline for translating the most promising agents into the clinic. The mechanism of action, preclinical data, epidemiological evidence, and results from available clinical trials are discussed for each class of compounds. Selected keratinocyte carcinoma chemoprevention studies also are considered, and a rationale for their inclusion is presented. These data are summarized in a table that lists the type and level of evidence available for each class of agents. Also included in the discussion is an assessment of additional research necessary and the likelihood that a given compound may be a suitable candidate for a phase 3 clinical trial within the next 5 years.

Oral Photoprotection: Effective Agents and Potential Candidates

Electromagnetic radiation in the ultraviolet, visible, and infrared ranges produces biologic effects in humans. Where some of these effects are beneficial, others are harmful to the skin, particularly those stemming from ultraviolet radiation (UVR). Pharmacological photoprotection can be topical or systemic. Systemic photoprotection is often administered orally, complementing topical protection. New and classic oral agents (e.g., essential micronutrients as vitamins, minerals, polyphenols, carotenoids) are endowed with photoprotective and anti-photocarcinogenic properties. These substances bear the potential to increase systemic protection against the effects of electromagnetic radiation in the UV, visible, and infrared ranges. Protective mechanisms vary and include anti-oxidant, anti-inflammatory, and immunomodulatory effects. As such, they provide protection against UVR and prevent photo-induced carcinogenesis and aging. In this review, we present state of the art approaches regarding the photoprotective effects of vitamins and vitamin derivatives, dietary botanical, and non-botanical agents. A growing body of data supports the beneficial effects of oral photoprotection on the health of the skin. More studies will likely confirm and expand the positive impact of oral dietary botanicals as complementary measures for photoprotection.

Dermatological Complications After Solid Organ Transplantation

Organ transplant recipients (OTRs) are a population at high risk for cutaneous adverse events. Their early recognition and appropriate treatment is an important component of the clinical management of OTRs and should be optimally dealt with by dermatologists working in the context of a transplant dermatology clinic. Skin examination should be a standard procedure before performing organ transplantation to assess conditions which may be difficult to manage after the transplant procedure has been performed or which may represent a contraindication to transplantation, e.g., malignant melanoma. It also offers an opportunity to educate patients on skin care after organ transplantation. Skin infections can occur at any time after organ transplantation and include viral, bacterial, and fungal opportunistic infections. The risk of reactivation of latent viruses, such as varicella-zoster virus (VZV) and cytomegalovirus (CMV), is high. Bacterial infections are frequent and may be caused by unusual agents such Actinomyces, Mycobacteria, Legionella, or Nocardia. A large spectrum of fungal infections may occur, ranging from superficial (e.g., dermatophytes) to deeper and more severe ones (Alternaria, Aspergillus, Cryptococcus, Histoplasma). Drug-related idiosyncratic reactions usually occur early after the introduction of the causative drug, e.g., hypersensitivity reaction to azathioprine. On the long-term run, cutaneous effects due to cumulative drug toxicity, e.g., sebaceous hyperplasia from cyclosporine, may appear. Rare immunologically driven inflammatory reactions may occur in OTRs such as GVH or autoimmune disease. Tumors are particularly frequent. Kaposi's sarcoma, associated with persistent human herpes virus 8 (HHV8) infection, and cutaneous anaplastic large-cell lymphoma (ALCL) occur early after transplantation. Other cancers, such as nonmelanoma skin cancer (NMSCs), associated with persistent human papillomavirus (HPV) infections, malignant melanoma, Merkel cell carcinoma, or adnexal tumors, manifest later with an incidence which is much higher than observed in the general population. The incidence increases further after a first NMSC occurs.