The role of screening in the management of skin cancer

A Two-Year Regional Program for the Early Detection of Cutaneous Melanoma

Background

A regional program for the early diagnosis of cutaneous melanoma involving general practitioners was effective in 1997–1998 in the Friuli Venezia Giulia region in Northern Italy. The aim of the 2-year program was to evaluate the role of a skin examination performed by general practitioners in people older than 18 years without known skin lesions and spontaneously presenting to their offices for any reason, with referral of suspect cases to a pre-identified regional dermatology or plastic surgery institution.

Methods

In the preparatory phase (late 1995 and 1996), all general practitioners operating in the Friuli Venezia Giulia region (n = 1,038) were asked to participate in the program. Support from all regional dermatology, pathology and plastic surgery institutions was obtained. Operational procedures for the management of referred people were defined, and educational meetings directed to general practitioners interested in the program were held. Skin examinations by general practitioners started at the end of 1996 and took place during 1997 and 1998. Subsequently, information was obtained from participating general practitioners and from pathology institutions about the number and thickness of diagnosed melanomas, as well as the number of diagnosed skin carcinomas and dysplastic nevi. In addition, the thickness distribution of all melanomas diagnosed in the Friuli Venezia Giulia region before and during the program was obtained.

Results

A total of 153 general practitioners participated in the program, but only 74 were active and assessable. A total of 11,040 skin examinations was performed by these 74 general practitioners (median, 75 per general practitioner). In all, 820 people (7.4%) were referred for dermatological evaluation (median, 8 per general practitioner). Among these 820 people, at least 38 melanomas (4.6% of referred cases) were detected (18 ≤1.5 mm, 11 >1.5 mm thick, unknown in 9). The dermatological examinations/diagnosed melanomas ratio was 21. In addition, 94 skin carcinomas and 50 dysplastic nevi were detected. At the regional level, the percentage of thin melanomas rose from 65.3% in 1995–96 to 72.2% in 1997–98 (P = 0.04), whereas the number of thick melanomas declined.

Conclusions

In our study, only a few general practitioners chose, in the absence of incentives, to participate in the study. However, the yield of melanomas, most of which were thin, was considerably high and the workload was acceptable. This compares favorably to experiences where dermatologists were involved directly without a filter work by general practitioners.

Risk prediction models for melanoma: a systematic review

Melanoma incidence is increasing rapidly worldwide among white-skinned populations. Earlier diagnosis is the principal factor that can improve prognosis. Defining high-risk populations using risk prediction models may help targeted screening and early detection approaches. In this systematic review, we searched Medline, EMBASE, and the Cochrane Library for primary research studies reporting or validating models to predict risk of developing cutaneous melanoma. A total of 4,141 articles were identified from the literature search and six through citation searching. Twenty-five risk models were included. Between them, the models considered 144 possible risk factors, including 18 measures of number of nevi and 26 of sun/UV exposure. Those most frequently included in final risk models were number of nevi, presence of freckles, history of sunburn, hair color, and skin color. Despite the different factors included and different cutoff values for sensitivity and specificity, almost all models yielded sensitivities and specificities that fit along a summary ROC with area under the ROC (AUROC) of 0.755, suggesting that most models had similar discrimination. Only two models have been validated in separate populations and both also showed good discrimination with AUROC values of 0.79 (0.70-0.86) and 0.70 (0.64-0.77). Further research should focus on validating existing models rather than developing new ones.

Knowledge, perceptions, and practices of chiropractic interns in the early detection of atypical moles

OBJECTIVE

Skin cancer is a major public health concern in the United States. Chiropractic physicians and interns need to recognize and refer patients with atypical moles and skin cancer. The purpose of this study was to test chiropractic interns about their current knowledge, practices, and perceptions of atypical moles and skin cancer.

METHODS

This study was a cross-sectional study using chiropractic interns at 2 chiropractic colleges who received a 26-item survey that used a 5-point Likert scale involving close-ended questions regarding demographics, importance, knowledge, and clinical images regarding atypical moles and skin cancer. Frequencies and odds ratios (ORs) were generated using multiple regression models.

RESULTS

A total of 217 surveys were collected in the study. The importance of skin cancer recognition as a predictor of practice patterns was examined. Interns who stated it was "important/very important" to recognize skin cancer were slightly more likely to state they "frequently/always" scanned patient's skin on the initial visit, were more likely to state they "frequently/always" scanned on a treatment visit (OR = 3.30; 95% confidence interval [CI], 1.6-6.9), and stated they had noticed a mole that needed follow-up (OR = 3.04; 95% CI, 1.52-6.10). However, interns were no more likely to state they documented moles in the soap notes (OR = 1.38; 95% CI, 0.77-2.47) or to know the warning signs of melanoma (OR = 0.76; 95% CI, 0.40-1.46).

CONCLUSION

As skin cancer continues to increase in prevalence, chiropractic interns can serve in the primary screening process of patients with atypical moles; and chiropractic education should emphasize the opportunity to detect and assess atypical moles as a routine part of primary prevention in clinical education.

Creation and test of a questionnaire for self-assessment of melanoma risk factors

The objective of this study was to create a self-administrated questionnaire for people to enable them to assess their own melanoma risk factors. To test the validity of this questionnaire in a large prospective study, the answers given by the patient were systematically checked by his or her general practitioner. In this prospective study, the choice of questions was based on a review of the literature. The validity of the questionnaire was assessed by testing 1500 consecutive patients attending a consultation with their general practitioner. Considerable variations concerning the prevalence of different melanoma risk factors were noticed in the population: 44.1% had a phototype I or II, 41% had severe sunburn during infancy, 29.9% had freckling tendency, 22% had more than 50 naevi and 1.4% a personal history of melanoma. In total, 45% had more than one melanoma risk factor. The accuracy of the answers given by the patients was assured by the correction given by their general practitioners. The percentage of correct answers given by the patients was 79.9% for the phototype, 90.6% for freckling tendency, 86.6% for the number of naevi, 96.5% for severe sunburn during infancy and 98.1 and 95.8% for personal and familial history of melanoma. This study confirms that individuals with multiple risk factors for melanoma are common among patients consulting their general practitioners. Furthermore, self-screening with the self-assessment questionnaire is easily feasible and is accurate for identifying high-risk individuals. This tool might be useful for carrying out melanoma-targeted screening.

Screening and early detection of skin cancer

Skin cancer is the most common type of cancer in the United States. US incidence of malignant melanoma is increasing faster than any other type of cancer. To minimize increasing morbidity and mortality rates, it is imperative that appropriate screening and early detection of skin cancer become more widespread. All physicians who see patients clinically have the potential for detecting skin cancers. The scope of skin cancer as a health-care problem is discussed. Evidence for the effectiveness and necessity of skin cancer screening and early detection is presented. Costs of screening and detection are discussed in relation to impact on treatment costs and overall costs of skin cancer burden. Current methods and recommendations for skin cancer screening and detection are reviewed, especially with regard to individuals and populations that may require more specialized or intensive screening and follow-up. Newer approaches involving instrument-assisted screening and detection of skin cancer are under intense development, and these exciting emerging technologies are reviewed.

Three-point checklist of dermoscopy: an open internet study

BACKGROUND

In a pilot study, the three-point checklist of dermoscopy has been shown to represent a valid and reproducible tool with high sensitivity for the diagnosis of skin cancer in the hands of a small group of nonexperts.

OBJECTIVES

To re-evaluate these preliminary results in a large number of observers independently from their profession and expertise in dermoscopy.

METHODS

The study was conducted via the internet to provide worldwide access for participants. After a short web-based tutorial, the participants evaluated dermoscopic images of 165 (116 benign and 49 malignant) skin lesions (15 training and 150 test lesions). For each lesion participants scored the presence of the three-point checklist criteria (asymmetry, atypical network and blue-white structures). Kappa values, odds ratios, sensitivity, specificity and likelihood ratios were estimated.

RESULTS

Overall, 150 participants joined the study. The three-point checklist showed good interobserver reproducibility (kappa value: 0.53). Sensitivity for skin cancer (melanoma and basal cell carcinoma) was 91.0% and this value remained basically uninfluenced by the observers' professional profile. Only 20 participants lacking any experience in dermoscopy performed significantly more poorly, but the sensitivity was still remarkably high (86.7%) when considering that they were untrained novices in dermoscopy. The specificity was 71.9% and was significantly influenced by the profession, with dermatologists performing best.

CONCLUSIONS

Our study confirms that the three-point checklist is a feasible, simple, accurate and reproducible skin cancer screening tool.

Photodynamic therapy and imiquimod immunotherapy for basal cell carcinomas

Photodynamic therapy (PDT) and topical imiquimod immunotherapy (TII) are two recently introduced treatment modalities for certain types of basal cell carcinomas (BCC). We present a review of the relevant literature and report our own findings regarding the efficacy and tolerance of PDT and TII in the treatment of BCCs. According to published studies, the cure rates range from 75-95% for PDT and 42-100% for TII, depending on treatment modalities and BCC type. In our observations, 13 patients with nodular or superficial BCCs were treated by PDT using two courses of 3-hour topical application of methyl aminolevulinate, followed by 8 minutes illumination (lambda = 634 nm, e = 37J/cm2). Biopsies were taken before and one month after PDT. Side effects including pain and crusting were assessed. Eight patients with superficial BCC were treated by TII using 3 monthly courses each consisting of 3 weekly applications for 3 weeks followed by one week out of treatment. Biopsies were taken before and after 3 months of TII. Adverse reactions including erythema, oozing, ulceration, and crusting were recorded. Clinico-histological cure was obtained in 12/13 PDT cases as assessed after 1 month, and in 6/8 TII cases after 3 months. Minimal pain during illumination and crust formation were observed in 7/13 and 3/13 PDT cases, respectively. Variable erythema, oozing, ulceration, and crusting were observed in all TII-treated lesions. It is concluded that PDT represents an active and well tolerated alternative treatment for both nodular and superficial BCCs. TII also shows activity, although the tolerance may be poor and cure needs a longer time to be obtained. The final cosmetic appearance was fine following both PDT and TII procedures. Both PDT and TII may leave intact neoplastic aggregates inside the skin. They cannot be clinically perceived, leading to unexpected recurrences. It is stressed that the currently available efficacy information about PDT and TII deals with short term follow-up periods. A 5-year follow-up must be awaited before drawing firm conclusions.

Dermoscopy for skin cancer detection

PURPOSE OF REVIEW

The worldwide incidence of melanoma and nonmelanoma skin cancers is increasing alarmingly. The development of new techniques such as dermoscopy leads to a consequent progress in skin cancers screening. The purpose of this review is to highlight recent advances in dermoscopy, reviewing primary research articles published in the last year.

RECENT FINDINGS

With the recent standardization of diagnostic procedures obtained by the Consensus Net Meeting on Dermoscopy and the definition of new melanoma-specific criteria, the efficacy in early melanoma diagnosis is improved. Dermoscopy is cost effective, leading to a decreased number of excised benign lesions, and the dermoscopic follow-up allows early detection of melanomas. However, the technique must be performed by experts in order not to miss melanomas. For this reason, instruction in dermoscopy is mandatory. Moreover, computer-aided diagnosis has been tested to be a valid support for physicians. Teledermoscopy is a new tool that allows a second expert opinion to manage atypical lesions.

SUMMARY

Dermoscopy opens up a new dimension on clinical morphology of skin lesions. Digital follow-up examinations, computer-aided diagnosis, and teledermoscopy are new facilities that will change the current management of skin cancers in general and melanoma in particular. Dermoscopy in the hands of experienced physicians has higher discriminatory power than naked-eye examination to detect skin cancers.

High frequency of melanoma-associated antigen or HLA class I loss does not correlate with survival in primary melanoma

Melanoma-associated antigens are at the center of many immunotherapeutic trials in melanoma. Little is known about the impact of antigen expression on the natural course of disease. We stained 110 cases of primary melanoma with a median follow-up of 13 years (range 10-18 years) for melanoma-associated antigens gp100, MelanA/MART-1, MAGE-3, tyrosinase, and for HLA class I molecules. Of 91 cases evaluated, we found immunoreactivity for gp100, MelanA/MART-1, and tyrosinase in 88%, 80%, and 87% of primary tumors, respectively, for MAGE-3 in 37% and for HLA class I in 86% of primary tumors. Loss, that is, heterogeneous expression within primary tumors, was most pronounced for gp100 (73% of primary tumors) and least for MAGE-3 (27% of primary tumors). MelanA/MART-1 and tyrosinase expression loss was 58% and 59% of primary tumors, respectively. There was a high rate of expression loss for HLA class I (74%). Univariate and multivariate statistical analysis of expression in primary tumors and loss of melanoma antigens as well as HLA class I in individual primary tumors showed no significant correlation to overall survival. Loss of gp100 and loss of tyrosinase expression showed a negative survival trend over homogeneous expression of these antigens, although not reaching statistical significance (P = 0.08 and P = 0.09, respectively). We conclude that loss of melanoma antigen expression as well as HLA class I expression is a frequent observation in primary melanoma. However, no statistically significant correlation between loss of these antigens in individual primary tumors and negative impact on overall survival was found in our cohort.

Skin cancer screening campaign in the German speaking Community of Belgium

The incidence of primary malignant melanoma (MM) and skin carcinomas, including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), is progressively raising. As long as their diagnosis and therapeutic managements are initiated early, their prognosis remains favorable. This underlines the importance of early recognition of skin cancers. Furthermore, it has been demonstrated that skin cancer screening programs are efficacious in increasing the population awareness of the early signs of skin cancer and of the dangers of UV - exposure. A skin cancer screening campaign was organised by dermatologists of the German-speaking Community of Belgium in cooperation with the Department of Family, Health, and Social Affairs of the Regional Ministry of the German-speaking Community of Belgium. In order to increase the screening selectivity, two risk populations were targeted; patients presenting 30 or more moles, and patients over 50 years of age presenting recent skin changes of the head and neck area. A media campaign using radio, television and daily press was started to increase the population awareness of the dangers of UV exposure and of the early signs of skin cancer. During 2 screening days, three-hour sessions were organised in 2 health centers located in Eupen and St Vith. A total of 148 patients were examined. A total of 124/148 patients met the selection criteria predefined during the media announcement. The simultaneous presence of 4 dermatologists during the screening sessions allowed a second opinion for warning lesions. Four BBCs as well as 23 patients pesenting dysplastic nevi were clinically diagnosed. During the 2 months following the screening campaign 5 MMs were identified by the same dermatologists in their routine practice. In conclusion, this skin cancer screening campaign led to the diagnosis of 4 carcinomas. The campaign furthermore increased the patient awareness, permitting the diagnosis of 5 MMs during the 2 following months. This figure represents about 30% of all MMs diagnosed yearly in this region of Belgium.

Validity of an unsupervised self-administered questionnaire for self-assessment of melanoma risk

Mass screening for cutaneous melanoma is impracticable because of its low yield and high costs. The validity of self-selection of high-risk individuals through self-assessment of melanoma risk factors is not known. The aim of this study was to assess the validity of an unsupervised self-administered questionnaire for the self-assessment of melanoma risk. In a case-control study, melanoma cases (n = 202) and controls (n = 202) matched for age and gender filled in a questionnaire about melanoma risk factors. After filling in the questionnaire, all participants were interviewed and examined by a dermatologist in order to compare self-assessment with physician-assessment. The number of naevi, skin phototype and ultraviolet damage to the skin were identified as independent risk factors for melanoma on both self-assessment and physician-assessment. Receiver operating characteristics analysis showed no statistically significant difference between the accuracy of the self-assessment-based model and the model based on physician-assessment. While excluding 90% of the controls, the self-assessment-based high-risk group included 39% (95% confidence interval 31-48%) of the melanoma patients and the physician-assessment-based high-risk group included 42% (95% confidence interval 33-52%) of the melanoma patients. In conclusion, an unsupervised self-administered questionnaire is, to some extent, useful for the identification of individuals at high risk for melanoma. The moderate accuracy of self-assessment and physician-assessment to identify individuals at high risk for melanoma is a limitation for the practicability of targeted melanoma screening in general.

Malignant melanoma

In the European Community cutaneous melanoma accounts for 1 and 1.8% of cancers occurring in men and women, respectively. The incidence rate is increasing faster than that of any other tumour. Sun exposure, patient's phenotype, family history, and history of a previous melanoma are the major risk factors. The change over a period of months is the main sign of a skin lesion turned into a melanoma. The ABCDE scheme for early detection of melanoma is commonly accepted. A new staging classification will be published in the next AJCC/UICC Cancer Staging System Manual in 2002. The clinical course of melanoma is determined by its dissemination and depends on thickness, ulceration, localisation, gender and histology of the primary tumour. Tumour stage at diagnosis remains the major prognostic factor. Surgery is the standard treatment option for operable local-regional disease. Sentinel node biopsy represents a promising experimental approach in the clinical detection and early treatment of occult lymph node involvement. For metastatic inoperable patients systemic chemotherapy can be attempted, while radiation therapy has to be considered as palliative treatment. No studies concerning frequency of follow-up are currently available, but common procedures may be performed.

Increased effectiveness of targeted skin cancer screening in the Veterans Affairs population of Northern California

BACKGROUND

Skin cancer screening in populations at increased risk may be more useful than mass screening. We assessed the effectiveness of screening a targeted population in the Veterans Affairs Palo Alto Health Care System (VAPAHCS) for skin cancer/precancer detection and follow-up.

METHODS

We studied the demographics, presumptive diagnoses, and outcome of 374 participants in free screening clinics conducted over a 3-year period in multiple northern California sites. The number of attendees with presumptive actinic keratosis (AK), basal cell carcinoma (BCC), squamous cell carcinoma (SCC), dysplastic nevus (DN), and melanoma was noted.

RESULTS

Three hundred sixty-two males and 12 females were screened (mean age 63.4 years); 74% were Caucasian. Two hundred three individuals (54%) had a positive screen including 139 (52%) with presumptive AK, 41 (11%) with BCC, 9 (2%) with SCC, and 14 (4%) with DN versus potential melanoma. One hundred one (50%) of referred individuals were subsequently evaluated by VAPAHCS dermatologists. Biopsy was performed in 34/36 cases (94%), with a positive predictive value of 62% in patients with suspected BCC, 43% for SCC, 37.5% for DN and 12.5% for melanoma.

CONCLUSIONS

Targeting a predominantly elderly Caucasian population with minimal to no prior dermatologic care yielded high rates of detection for precancers, skin cancer, and atypical nevi, and resulted in an increased percentage of pathologically confirmed nonmelanoma skin cancer, particularly BCC, compared to prior screening studies and population-based cancer registries.

Audit of a melanoma screening day in the U.K.: clinical results, participant satisfaction and perceived value

BACKGROUND

The incidence of cutaneous malignant melanoma (MM) has risen significantly over the last 50 years in caucasian populations. Mortality is related to the Breslow thickness of the lesion, and early detection followed by complete surgical excision is crucial to reducing this. Skin screening events have been advocated as a means of detecting greater numbers of MMs in the earlier and thinner stages.

OBJECTIVES

To assess the feasibility and effectiveness of this approach in the U.K.

METHODS

The Department of Dermatology, Singleton Hospital, Swansea, U.K. offered a 1-day melanoma screening event in summer 1998 at which 832 consecutive individuals were seen. A postal questionnaire 1 year after the event audited participant perceived value and satisfaction.

RESULTS

Three MMs were identified (yield 1 : 277), all < 0.75 mm in thickness. Despite high participant satisfaction and perceived value, the pick-up rate of malignancy was significantly lower than at rapid access pigmented lesion clinics.

CONCLUSIONS

In a country such as the U.K., with comprehensive health coverage and a low incidence of MM, triage for melanoma and referral to specialists by general practitioners may be more cost and time effective.