Nicotinamide for Skin-Cancer Chemoprevention in Transplant Recipients

BACKGROUND

Immunosuppressed organ-transplant recipients have an increased incidence of, and mortality from, skin cancer. Nicotinamide (vitamin B3) enhances the repair of ultraviolet (UV) radiation-induced DNA damage, reduces the cutaneous immunosuppressive effects of UV radiation, and reduces the incidence of keratinocyte cancers (including squamous-cell and basal-cell carcinomas) and actinic keratoses among high-risk immunocompetent patients. Whether oral nicotinamide is useful for skin-cancer chemoprevention in organ-transplant recipients is unclear.

METHODS

In this phase 3 trial, we randomly assigned, in a 1:1 ratio, organ-transplant recipients who had had at least two keratinocyte cancers in the past 5 years to receive 500 mg of nicotinamide or placebo twice daily for 12 months. Participants were examined for skin lesions by dermatologists at 3-month intervals for 12 months. The primary end point was the number of new keratinocyte cancers during the 12-month intervention period. Secondary end points included the numbers of squamous-cell and basal-cell carcinomas during the 12-month intervention period, the number of actinic keratoses until 6 months after randomization, safety, and quality of life.

RESULTS

A total of 158 participants were enrolled, with 79 assigned to the nicotinamide group and 79 to the placebo group. The trial was stopped early owing to poor recruitment. At 12 months, there were 207 new keratinocyte cancers in the nicotinamide group and 210 in the placebo group (rate ratio, 1.0; 95% confidence interval, 0.8 to 1.3; P = 0.96). No significant between-group differences in squamous-cell and basal-cell carcinoma counts, actinic keratosis counts, or quality-of-life scores were observed. Adverse events and changes in blood or urine laboratory variables were similar in the two groups.

CONCLUSIONS

In this 12-month, placebo-controlled trial, oral nicotinamide therapy did not lead to lower numbers of keratinocyte cancers or actinic keratoses in immunosuppressed solid-organ transplant recipients. (Funded by the National Health and Medical Research Council; ONTRANS Australian New Zealand Clinical Trials Registry number, ACTRN12617000599370.).

An Australian tertiary hospital analysis of outpatient dermatology clinical and demographic characteristics

OBJECTIVES

Literature on dermatology outpatient demographic and clinical data is limited, and the few studies on this topic are mainly conducted overseas, with medical systems and case mix different to Australia. This study presents demographic data relating to dermatology public outpatient referrals to a tertiary hospital in Brisbane, Australia, and determines what additional structured data should be collected to formulate and evaluate initiatives to address service issues such as referral quality, triage process and wait times.

METHODS

A four-year retrospective audit was undertaken, summarising all referrals (n = 7140) and clinical dermatology encounters (n = 53 844) between January 2016 and December 2019 at Princess Alexandra Hospital (PAH), the largest hospital in Metro South Health (MSH), serving a population of one million. PAH has one of the two largest public dermatology clinics in Queensland and is the only dermatology service within MSH.

RESULTS

Patient demographic data, wait time by triage category, referral rates over time and encounter durations were collected. Structured diagnostic data (e.g. ICD-10 coding) of the provisional diagnosis, comorbidities, medications and the final diagnosis are not collected in a structured format and would be a valuable addition.

CONCLUSIONS

The clinical burden of public dermatology is increasing. Both collection and analysis of structured data pertaining to the referrals and encounters are important to help formulate, implement and evaluate initiatives that aim to improve health service provision in this area.

Anatomic Distribution of Cherry Angiomas in the General Population

BACKGROUND

Cherry angiomas are common benign vascular skin lesions of unknown aetiology, found largely on the trunk. However, their exact anatomic distribution besides their truncal predisposition, and how they manifest in the general population, has not been characterised.

METHODS

Three-dimensional (3D) total body imaging was obtained from 163 adult participants of a general population cohort study in Brisbane, Australia. Demographic, phenotypic, and sun behaviour characteristics were collected using a standard questionnaire along with history of melanoma and keratinocyte cancers. Cherry angiomas were identified using an automated classification algorithm with a sensitivity of 87% and a specificity of 99%, developed specifically for this study population.

RESULTS

The 3D total body images of 163 participants were analysed. Participants had a median age of 57 years and 61% were male. On average, males had more angiomas than females (median of 16 vs. 12) and the number and size of cherry angiomas increased with age. In addition to male sex and age, an increase in angiomas was associated with Caucasian ancestry other than British/Irish only, fair skin colour opposed to medium/olive, having green/hazel eyes compared to blue/grey, and personal history of melanoma. The most common site for cherry angiomas was the front trunk, followed by the back. Interestingly, although males had more angiomas overall, females had more angiomas on the legs.

CONCLUSION

Describing the distribution of cherry angiomas by body site is an important step towards further understanding of the aetiology of angiomas. While personal history of melanoma is associated with an increased number of cherry angiomas, whether this association is prognostic, co-occurs with development of melanoma, or is merely fortuitous requires further investigation.

Teledermatology Adaptations in the COVID-19 Era

The COVID-19 pandemic has required health services worldwide to adapt to dramatically changing healthcare needs and risks across all medical specialties. In the dermatology department at Princess Alexandra Hospital, Brisbane, Australia, we developed and implemented a teledermatology system with 1 week's notice to help reduce infection risk bidirectionally, while saving patients many hours of travel and waiting time with acceptable technological substitutes for the clinical encounters. In this study, we report the efficacy and tolerability of our telephone consultation and store and forward imaging system, including patient experience from validated survey data. Our design, implementation and usage of a remote-default system provides experience and lessons to draw upon in developing future telemedicine systems to address dermatology service maldistribution – an issue affecting large areas of Australia – as well as preparedness for future infection mitigation requirements.

Technology transfer in Europe: a case study of invertebrate neuroscience research

Originally identified and defined as a concept in industrial and business communities, technology transfer is now being recognized as an important factor within the scientific research community. A recent study undertaken within the field of UK invertebrate neuroscience research generates several interesting conclusions. In this article, Huw A. Edwards and Elizabeth R.J. Bell discuss the study and its conclusions of a need for increased post-doctoral research mobility, the formation of consortia of research laboratories to apply for funding on an international scale, and the increased interest of the pharmaceutical industry in molecular and cellular techniques developed from fundamental invertebrate research.

An osmoregulatory syncytium and associated cells in a freshwater mosquito

In embryological terms the anal papillae are the product of eversion of the hindgut tissues. The rectum and the anal papillae have the same origin and have a marked structural similarity. The insect hindgut is very labile being able to produce salt transporting or 'chloride cells' from any of the tissues of which it is composed. The hindgut consists of four distinct regions: the ileum and part of the anal canal have a mechanical function, the rectum and the posterior anal canal contain transporting cells. Two new types, 'interstitial' and 'tertiary' are reported in the rectum. The structure of the anal papillae changes with increased salinity. Changes in the plasma membranes alter the surface area for transport. Changes in the number of mitochondria are not accompanied by changes in oxygen consumption. If mitochondria are the site of oxidative metabolism then their number does not control the level of oxygen consumption. In Aedes aegypti the papillary epithelium appears to be a syncytium. Across the lumen of the papillae there are cellular sheets supporting the tracheoles. At the base of the papillae there is a cellular transition zone; circular muscles in this region may be used to occlude the papillae. The control of salt transport may be hormonal.