New Vitamin D and Sun Exposure Guidelines

New Vitamin D and Sun Exposure Guidelines

Australian sun exposure recommendations now consider skin type and risk of skin cancer in the Australian and New Zealand Journal of Public Health, February 2024.

People with lighter skin tones (Fitzpatrick I-IV) are at higher risk of skin cancer and should minimise sun exposure during peak UV hours (UV index 3 or higher) and use sun protection. They can still get enough vitamin D with short exposures during non-peak hours.

People with darker skin tones (Fitzpatrick V-VI) have a lower risk of skin cancer and may need more sun exposure to get enough vitamin D. They may not need daily sunscreen but should use it during prolonged sun exposure.

Our doctors can advise on personalised recommendations and vitamin D supplementation if needed. Public health messages will still focus on skin cancer prevention.

Non-Melanoma Skin Cancer killing more people than Melanoma

Non-Melanoma Skin Cancer killing more people than Melanoma

A new study presented at the European Academy of Dermatology and Venerology (EADV) Congress reveals surprising findings about skin cancer. While melanoma is often considered the most dangerous form, non-melanoma skin cancer (NMSC) is now causing more deaths globally.

In 2020, NMSC caused over 63,700 deaths compared to melanoma's estimated 57,000, despite being less likely to spread or be fatal per individual case.  This discrepancy is due to the much higher prevalence of NMSC, with nearly 1.2 million reported cases worldwide in 2020 compared to 324,635 melanoma cases.

Fair-skinned, elderly populations in specific countries like the US, Germany, and Australia are most affected, but even darker-skinned populations face significant risk.

To Shave, or not to Shave?

To Shave Or Not to Shave?

Melanoma is the most lethal form of skin cancer. Accurate diagnosis and early treatment are crucial for improving survival. Biopsy is a key step in diagnosis, and while excision biopsy is recommended, some melanomas are diagnosed using shave biopsy (which has a high rate of deep margin positivity, 42.9%).

However, a recent journal article in the Annals of Surgical Oncology stated that shave biopsies translate to a relatively small number of patients who have their T-stage increased (7.7%) or require a change in treatment recommendation (2.3%) after wide local excision.  And so there was no significant difference in recurrence or survival rates between melanoma patients diagnosed with shave biopsy and other biopsy methods.

Ahmadi, O., Das, M., Hajarizadeh, B. et al. Impact of Shave Biopsy on Diagnosis and Management of Cutaneous Melanoma: A Systematic Review and Meta-Analysis. Ann Surg Oncol 28, 6168–6176 (2021)

TOTAL BODY PHOTOGRAPHY

Is there any benefit to performing skin photography or digital surveillance?

A recent article in the Australasian Journal of Dermatology compared the results of traditional melanoma surveillance, which involves regular full-skin examinations and immediate removal of suspicious lesions, to the results of two newer surveillance methods: total body photography (TBP) and sequential digital dermoscopy imaging (SDDI). They found that traditional surveillance resulted in a higher ratio of in situ to invasive melanomas (4.59:1) and a lower incidence of thick invasive melanomas (<1%) than TBP and SDDI. Delayed excision, which is inherent to photographic monitoring, carries at least some risk of melanoma progressing from a lower to a higher risk category.

This data raises the possibility that traditional skin examination and biopsy techniques (instead of photographic monitoring) may be safer and more effective.

Organ Transplants

Organ Transplantation

Organ transplant recipients (OTRs) are at an increased risk of developing squamous cell carcinomas (SCCs), a type of skin cancer. A recent study published in JAMA Dermatology compared SCCs in OTRs to SCCs in the general population. The study found that perineural invasion and invasion to or beyond subcutaneous fat were more than twice as common in OTRs as in the general population. Poorly vs well-differentiated SCCs were 3-fold more common in OTRs, and prevalence of SCCs greater than 20 mm vs 20 mm or smaller was moderately higher, with all differences significant. These findings suggest that SCCs in OTRs are more likely to be aggressive and have a worse prognosis than SCCs in the general population. This is likely due to the fact that OTRs are immunosuppressed, which makes them more susceptible to cancer development and progression. Early diagnosis and definitive management of SCCs in OTRs is essential to improving patient outcomes.

CHONDRODERMATITIS NODULARIS HELICIS

Chondrodermatitis Nodularis Helicis

In the Journal of Dermatologic Surgery, a novel treatment was proposed for Chondrodermatitis Nodularis Helicis (CDNH).  

CDNH is a common chronic condition characterised by a painful nodule on the ear which may have accompanying crusting or ulceration.  

CDNH is often difficult to treat or treatment only gives temporary benefit. Avoiding pressure is difficult to do when the lesion usually occurs on the favoured sleeping side.  Surgical excision is often plagued by recurrence.  

0.2 – 0.3 mL of Hyaluronic Acid (HA) was injected into the ear and found to provide significant relief from pain and clinical symptoms (including ulceration) in less than 1 – 2 weeks.  Sometimes a second follow-up injection was required 2 weeks later if there was extrusion of HA material through a pre-existing ulcer.  

No adverse events were noted other than the intentional visible bulging of the injected region.  And these good results were achieved long term with one patient maintaining the benefit for 5 years!

INVERSE DERMOSCOPIC APPROACH

Inverse Dermoscopic Approach

In the Journal of the American Academy of Dermatology, a study showed significant increase in diagnosis of lentigo maligna (Hutchinson’s Melanotic Freckle) when traditional training for dermoscopic pattern analysis was compared with inverse approach training.  

The dermoscopic features of actinic keratoses (sunspots), actinic lentigos or flat seborrhoeic keratoses (liver spots) are easy to identify.  An inverse approach involves diagnosis by identifying the absence of these features.  

Use of the inverse approach to dermoscopy outperformed traditional dermoscopic pattern analysis with diagnostic accuracy increasing by more than 60%!

CONFOCAL MICROSCOPY

Confocal Microscopy

Confocal microscopy (CM) is an optical imaging technique where laser light is focussed onto a defined spot at a specific depth and increased optical resolution is achieved by means of a spacial pinhole to block out-of-focus light in image formation.

CM has been used in the evaluation of skin cancer.  ‘Ex vivo’ (outside the living) for faster pathology assessment with greater accuracy for Moh’s surgery. And ‘in vivo’ (within the living or patient) providing high resolution images which are optically scanned in slices without need for a surgical biopsy.  

Unfortunately, as described in the British Journal of Dermatology, the availability of this procedure is limited due to the lack of reimbursement, low number of dedicated units, elevated cost and time consuming nature of the procedure in busy clinical settings.  

UVP RATED CLOTHING

UVP Rated Clothing

The sun emits different types of radiation. This is mainly visible (light) and infrared (heat). Ultraviolet radiation (UVR) is also emitted but it cannot be seen or felt. It can cause sunburn and other skin damage (including skin cancers). Covering our skin with clothing or shade reduces accumulation of exposure. A fabric with an Ultraviolet Protection (UVP) factor of 20 will allow 1/20 (5%) of UVR to pass through, or in other words, block 95% of the UVR. Tightly woven and heavier weight fabrics are more effective. Darker colours usually block more UVR. UV protection is reduced if a garment is overstretched, wet, or worn out. Loose fitting clothing is usually more protective than tight fitting clothing.

A UVP rating of 40 is described as giving excellent protection and will block 97.5% of UVR. The Australian/New Zealand Standard for Sun Protective Clothing states that the highest UVP rating for garments is 50. Those with higher rating are labelled 50+.

CALCIPOTRIOL AND 5-FLUOROURACIL (5-FU)

Calcipotriol and 5 Fluorouracil (5-FU)

Cytokines are cell signalling molecules that aid cell to cell communication in immune responses and stimulate cells to move toward sites of inflammation.

Thymic stromal lymphopoeitin (TSLP) is an epithelium-derived cytokine that induces a robust anti-tumour immunity in barrier-defective skin. Calcipotriol (Daivonex), an ointment most commonly used in psoriasis, is a topical TSLP inducer.

5-FU cream (Efudix) is an anti-metabolite that blocks the growth of abnormal cells and is frequently used to treat pre-cancerous solar keratoses. But there are major disadvantages including the long treatment/healing duration (1-2 months) and the severity of the side effects - pain, irritation, burning, crusting, photosensitivity.

Efudix cream and Calcipotriol ointment used together (FU/Cal) twice daily for a 4-day treatment of solar keratoses has been shown to be more effective than using Efudix alone! The short treatment duration and minimal side-effect profile in a trial conducted at Washington University and Massachusetts General Hospital highlight the advantages of this combined therapy which resulted in a specific induction of CD4+ ’T helper cell’ immune response against solar keratoses. These are considered helper cells because they do not neutralise but trigger the body’s immune responses.