Awareness, knowledge, and attitudes towards sun protection among patients with melanoma and atypical mole syndrome

Incidence of Nonmelanoma Skin Cancers in Alberta, Canada, From 2007 to 2018

BACKGROUND

Nonmelanoma skin cancer (NMSC) is the most common malignancy affecting Caucasian populations and has been seeing steady increases in incidence globally for decades. Our previous study (from Alberta, Canada) had shown a plateau in the incidence rates for NMSC. This contrasts with data from other regions within Canada and throughout the world that indicated a continued increase in incidence rates of NMSCs.

OBJECTIVES

The objective of this study was to provide an update on the trends in incidence of NMSC in Alberta, Canada, from 2007 to 2018.

METHODS

A retrospective analysis of patients from Alberta diagnosed with NMSC from 2007 to 2018 inclusive was conducted with data retrieved from Alberta Cancer Registry. Sex-, age-, anatomical location-, NMSC subtype-, stage-specific incidence rates and trends were examined.

RESULTS

From 2007 to 2018, overall incidence rates of NMSC increased by 36%. Invasive squamous cell carcinoma (SCC) and in situ SCC demonstrated the most significant increase, invasive SCC [annual percentage change (APC) 3.48, P = .014] and in situ SCC (APC 5.61, P = .0001). In addition, we were able to determine that females had the most significant increases in NMSC incidence rates from 2007 to 2018 particularly invasive SCC (APC 3.03, P = <.0001) and in situ SCC (APC 5.08, P = <.0001).

CONCLUSIONS

After initial levelling of NMSC incidence in Alberta in the early part of 21st century, the incidence of NMSC continues to increase over the past decade. The reasons for this change are not clear and likely multifactorial.

A multicenter case-control study comparing sun exposure habits and use of photoprotection measures in patients diagnosed with different types of skin cancer

BACKGROUND

While skin cancer awareness programs have significantly furthered public understanding about the harmful effects of the sun, there is a disparity between photoprotection knowledge and protection practices.

OBJECTIVE

To compare sun exposure habits and photoprotection measures in patients diagnosed with basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma versus controls.

METHODS

Multicentre case-control observational study carried out by 13 Spanish dermatologists between April 2020 and August 2022. Patients diagnosed with BCC, SCC, or melanoma were considered cases. The control group consisted of individuals with no history of skin cancer.

RESULTS

Of the 254 cases (56.2% female; mean age, 62.67 ± 15.65), 119 (31.2%) had BCC, 62 (16.27%) SCC, and 73 (19.1%) melanoma. The control group consisted of 127 (33.33%) individuals. Avoiding sun exposure between 12:00 and 16:00 was the most commonly used photoprotection measure (habitually/always: 63.1%), followed by the use of sunscreen (habitually/always: 58.9%). Patients with melanoma were less likely to use clothing and shade to avoid sun exposure (p < .05), whereas those with BCC and SCC reported greater use of head coverings (p = .01). BCC and SCC groups reported greater sun exposure 15 years prior, whereas controls reported greater use of sunscreen. However, at the time of this study all groups reported using SPF ≥ 21, and the majority SPF > 50. No differences were observed in photoprotection measures between people with and without a previous history of skin cancer.

CONCLUSIONS

We describe differences in photoprotection measures and sun exposure patterns among patients diagnosed with different skin tumor types. Whether these differences may influence the type of tumor each developed will require further investigation.

Diagnostic biopsy of cutaneous melanoma, sentinel lymph node biopsy and indications for lymphadenectomy

The incidence of cutaneous melanoma appears to be increasing worldwide and this is attributed to solar radiation exposure. Early diagnosis is a challenging task. Any clinically suspected lesion must be assessed by complete diagnostic excision biopsy (margins 1-2 mm); however, there are other biopsy techniques that are less commonly used. Melanomas are characterized by Breslow thickness as thin (< 1 mm), intermediate (1-4 mm) and thick (> 4 mm). This thickness determines their biological behavior, therapy, prognosis and survival. If the biopsy is positive, a wide local excision (margins 1-2 cm) is finally performed. However, metastasis to regional lymph nodes is the most accurate prognostic determinant. Therefore, sentinel lymph node biopsy (SLNB) for diagnosed melanoma plays a pivotal role in the management strategy. Complete lymph node clearance has undoubted advantages and is recommended in all cases of positive SLN biopsy. A PET-CT (positron emission tomography-computed tomography) scan is necessary for staging and follow-up after treatment. Novel targeted therapies and immunotherapies have shown improved outcomes in advanced cases.