Non-melanoma skin cancer: ten years of cancer-registry-based surveillance

Neoadjuvant Immunotherapy in Non-melanoma Skin Cancers of the Head and Neck

OPINION STATEMENT

Neoadjuvant immunotherapy will change the standard of care for advanced resectable cutaneous squamous cell carcinoma (cSCC) and possibly other non-melanoma skin cancers. With pathological complete response rates around 50% for cSCC in early studies, neoadjuvant therapy allows patients the possibility of significant reduction in tumor size, de-escalation of adjuvant therapy, and improved long-term outcomes. Patients must be carefully selected to ensure that there is a margin of safety with respect to resectability, such that if a tumor progresses on neoadjuvant therapy, there remains a curative surgical option that is acceptable to the patient. The optimal treatment paradigm is an area of active research, with many researchers questioning whether adjuvant therapy, or even local therapy, is necessary in patients who seem to have a complete response. The ability to predict who will respond will become even more critical to answer, as a significant number of patients do not want to risk their disease progressing, especially in cosmetically sensitive areas of the head and neck. Recent studies in melanoma show promise for improved response rates using combination therapies, and these strategies may apply to cSCC as well. The use of LAG-3 inhibitors or mRNA vaccine technology may further improve the utility of neoadjuvant strategies.

Current status of skin cancers with a focus on immunology and immunotherapy

Skin cancer is one of the most widespread cancers, with a significant global health effect. UV-induced DNA damage in skin cells triggers them to grow and proliferate out of control, resulting in cancer development. Two common types of skin cancer include melanoma skin cancer (MSC) and non-melanoma skin cancer (NMSC). Melanoma is the most lethal form of skin cancer, and NMSC includes basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and other forms. The incidence of skin cancer is increasing in part owing to a demographic shift toward an aging population, which is more prone to NMSC, imposing a considerable financial strain on public health services. The introduction of immunostimulatory approaches for cancer cell eradication has led to significant improvements in skin cancer treatment. Over the last three decades, monoclonal antibodies have been used as powerful human therapeutics besides scientific tools, and along with the development of monoclonal antibody production and design procedures from chimeric to humanized and then fully human monoclonal antibodies more than 6 monoclonal antibodies have been approved by the food and drug administration (FDA) and have been successful in skin cancer treatment. In this review, we will discuss the epidemiology, immunology, and therapeutic approaches of different types of skin cancer.

Risk of subsequent keratinocyte carcinomas after a first diagnosis in Tasmania, Australia

BACKGROUND/OBJECTIVE

A history of keratinocyte carcinoma (KC) is a risk factor for further KCs, but population-based studies quantifying the risk are lacking in Australia. We aimed to describe the risk of subsequent KCs after first KCs in the Australian state of Tasmania.

METHODS

Tasmanian residents identified in the Tasmanian Cancer Registry with a first histologically confirmed basal cell carcinoma (BCC), squamous cell carcinoma (SCC) or synchronous BCC and SCC (within 3 months) between January 1985 and December 2013 were followed up for at least 5 years for the development of a subsequent KC. Cumulative risk, incidence rates and standardised incidence ratios (SIRs) were calculated.

RESULTS

Those first diagnosed with BCC-only, SCC-only or synchronous BCC and SCC had (i) 5-year cumulative risks of subsequent KCs of 32%, 29% and 51%, (ii) annualised 5-year incidence rates of 8100/100,000 person-years at risk (PYR), 7747/100,000 PYR and 16,634/100,000 PYR and (iii) SIRs of 10.6 (95% CI: 10.5-10.6), 12.5 (95% CI: 12.4-12.6) and 313.0 (95% CI: 305.2-321.1), respectively. Risk estimates increased substantially when multiple (two or more) lesions of any type were diagnosed synchronously.

CONCLUSIONS

In the first Australian population-based study to describe the risk of subsequent KCs according to histological types, around one in three Tasmanians diagnosed with first KCs were diagnosed with subsequent KCs within 5 years. The risk of subsequent KCs was higher among those with a history of multiple synchronous lesions, especially if they included both BCC and SCC lesions.

Incidence Trends of Melanoma and Nonmelanoma Skin Cancers in Jordan From 2000 to 2016

PURPOSE

Skin cancers are among the commonest cancers worldwide, and the incidence of melanoma and non-melanoma skin cancer (NMSC) continues to rise worldwide. However, there are no comprehensive reports on skin cancer incidence in Jordan during the past two decades. This report investigates the incidence of skin cancers in Jordan, in particular their time trends for the period 2000-2016.

MATERIALS AND METHODS

Data on malignant melanomas (MMs), squamous cells carcinomas (SCCs), and basal cell carcinomas (BCCs) were extracted from the Jordan Cancer Registry for the period between 2000 and 2016. Age-specific and overall age-standardized incidence rates (ASIRs) were computed.

RESULTS

Two thousand seventy patients were diagnosed with at least one BCC, 1,364 with SCC, and 258 with MM. ASIRs were 28, 19, and 4 per 100,000 person-years for BCC, SCC, and MM, respectively. The BCC:SCC incidence ratio was 1.47:1. The risk of men developing SCCs was significantly higher than women (relative risks [RRs], 1.311; 95% CI, 1.197 to 1.436), but significantly lower for BCCs (RR, 0.929; 95% CI, 0.877 to 0.984) or melanomas (RR, 0.465; 95% CI, 0.366 to 0.591). Persons older than 60 years were at a significantly higher risk of developing SCCs (RR, 1.225; 95% CI, 1.119 to 1.340) or melanomas (RR, 2.445; 95% CI, 1.925 to 3.104), but at a significantly lower risk of developing BCCs (RR, 0.885; 95% CI, 0.832 to 0.941). The overall incidence rates of SCCs, BCCs, and melanomas increased over the 16-year study period, but this was not statistically significant.

CONCLUSION

To our knowledge, this is the largest epidemiologic study regarding skin cancers in Jordan and in the Arab world. Despite low incidence rates in this study, rates are higher than reported regional figures. This is likely due to standardized, centralized, and mandatory reporting of skin cancers, including NMSC.

Epidemiologic profile of skin tumors in the Philippine General Hospital: A descriptive cross‐sectional study

Background and Aims

Skin tumors are one of the most common complaints among patients due to their external location and esthetic reasons. Skin tumors have a wide spectrum from being benign, with only esthetic problems, to malignant, which can be fatal. This study aimed to describe the epidemiologic profile of skin tumors in the Philippine General Hospital Out‐patient Services.

Methods

This is a cross‐sectional study that describes the epidemiologic profile of the different skin tumors among Filipinos who consulted at the Philippine General Hospital Out‐patient Services.

Results

Benign skin tumors are more common than malignant ones. Benign skin tumors are commonly seen in middle‐aged adults, with a median age of 33 years. There was a higher proportion of benign tumors among females (n = 1256/1529, 82.15%) compared to males (n = 690/923, 74.76%). The site of predilection was the head and neck region. The most common benign skin tumor was the intradermal nevus. The older adult age group had a higher predilection for malignant tumors, with a median age of 57 years. Relatively, there was higher proportion of malignant tumors among males (n = 223/923, 25.24%) compared to females (n = 273/1529, 17.85%). The site of predilection is also the head and neck region. Among malignant skin tumors, basal cell carcinoma is the most common skin cancer.

Conclusion

The epidemiologic profile of skin tumors from patients seen in the Philippine General Hospital in terms of median age at diagnosis, sex preponderance, site of predilection, and tumor classification was similar to various Asian countries located in relatively the same latitude as the Philippines.

A Retrospective Chart Review of Skin Cancer Pattern and Clinical Outcomes Among Saudi Patients Visiting a Tertiary Care Hospital in Western Saudi Arabia From 1987-2016

Background Skin cancer is one of the most common cancers worldwide. However, limited studies have been conducted on this disease in Saudi Arabia. This study aimed to describe the prevalence, treatment modalities, and outcomes of skin cancer in a tertiary care hospital in western Saudi Arabia. Methods A retrospective review of the medical records of all Saudi patients visiting King Abdulaziz Medical City hospital in Jeddah between 1987 and 2016 was performed. Results In total, 132 patients were diagnosed with skin cancer during the study period, however, only 119 cases were analyzed because of missing information. The male-to-female ratio was 1.09:1. The age at diagnosis ranges from 16-94 (mean age: 63.3 years). The most common type of skin cancer was basal cell carcinoma, followed by squamous cell carcinoma and malignant melanoma. The most common anatomical site was the head and neck region. The most common form of treatment modality was surgery. Of the studied patients, 49.6% were cured, 20.2% were in remission, 12.6% relapsed, and 17.6% died. Conclusions This study showed an equal male to female ratio with variant cumulative incidence over the years. Surgery was the most common treatment modality and had the highest curative outcome. Primary care physicians should be probed further to raise awareness and screen their patients to ensure early detection of possible skin cancer.

Temporal trends in the incidence rates of keratinocyte carcinomas from 1978 to 2018 in Tasmania, Australia: a population-based study

OBJECTIVES

We described incidence trends of keratinocyte carcinomas (KCs)-namely basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)-in the Australian state of Tasmania.

METHODS

We identified histologically confirmed KCs within the Tasmanian Cancer Registry (TCR) and conducted assessments to ensure data quality. Age-standardised incidence rates were calculated for first (1985-2018) and annual KCs (1978-2018). Average annual percentage changes were computed using Joinpoint regression models.

RESULTS

The TCR is a reliable source of KC data. A total of 83,536 people were registered with a KC between 1978 and 2018. Age-standardised incidence rates of first KCs increased on average by 3% per annum for BCCs and 4% per annum for SCCs, reaching 363/100,000 and 249/100,000 in 2018, respectively. Age-standardised incidence rates of annual KCs increased on average by 5% per annum for BCCs and 6% per annum for SCCs, up to 891/100,000 and 514/100,000 in 2018, respectively. This increase was steeper for females than males and highest during the late 1980s and early 1990s. A change in trend around 2014 suggested that incidence rates have started to decline.

CONCLUSION

While the incidence of KCs in Tasmania increased substantially over 41 years, rates have recently plateaued and started to decline. The findings may reflect changes in sun exposure behaviours due to awareness campaigns, but high incidence rates in 2018 indicate that KCs still pose a substantial burden to this population.

Current and Future Trends in Molecular Biomarkers for Diagnostic, Prognostic, and Predictive Purposes in Non-Melanoma Skin Cancer

Skin cancer represents the most common type of cancer among Caucasians and presents in two main forms: melanoma and non-melanoma skin cancer (NMSC). NMSC is an umbrella term, under which basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and Merkel cell carcinoma (MCC) are found along with the pre-neoplastic lesions, Bowen disease (BD) and actinic keratosis (AK). Due to the mild nature of the majority of NMSC cases, research regarding their biology has attracted much less attention. Nonetheless, NMSC can bear unfavorable characteristics for the patient, such as invasiveness, local recurrence and distant metastases. In addition, late diagnosis is relatively common for a number of cases of NMSC due to the inability to recognize such cases. Recognizing the need for clinically and economically efficient modes of diagnosis, staging, and prognosis, the present review discusses the main etiological and pathological features of NMSC as well as the new and promising molecular biomarkers available including telomere length (TL), telomerase activity (TA), CpG island methylation (CIM), histone methylation and acetylation, microRNAs (miRNAs), and micronuclei frequency (MNf). The evaluation of all these aspects is important for the correct management of NMSC; therefore, the current review aims to assist future studies interested in exploring the diagnostic and prognostic potential of molecular biomarkers for these entities.

Nationwide Trends in the Incidence and Survival of Eyelid Skin Cancers in Korea

PURPOSE

This study provides a population-based report on eyelid skin cancer epidemiology showing trends in its incidence and survival in South Korea.

METHODS

For this population-based epidemiological study, nationwide cancer incidence data were obtained from the Korea Central Cancer Registry, covering the entire population. Age-standardised incidence rates (ASRs) and annual per cent changes (APCs) were calculated according to sex, histological types, stage, and date of diagnosis. The 5-year relative survival rates (RSRs) were estimated for patients diagnosed between 1993 and 2016.

RESULTS

The ASR increased from 0.27 per 100,000 population in 1999 to 0.61 in 2016, with an APC of 4.94%. The most common histopathological type was basal cell carcinoma (BCC), accounting for 67.5% of all eyelid skin cancers during 1999-2016, followed by sebaceous gland carcinoma (SGC, 10.7%), and squamous cell carcinoma (SCC, 10.6%). The number of localised cancer diagnoses tended to increase, compared to that of distant cancer. The 5-year RSR was nearly 100% when considering all eyelid skin cancers together. When considering them separately, the 5-year RSR of BCC was nearly 100% throughout, whereas for SGC and SCC, it gradually increased from 94.2% and 87.7% (1993-1995), respectively, to nearly 100% (2011-2016) for both. Melanoma had the lowest survival, although its survival has increased markedly since 1993.

CONCLUSIONS

Nationwide data used in this study showed an increase in incidence and survival rates of eyelid skin cancers in Korea. BCC was the most predominant type, and its proportion among all eyelid skin cancer cases has increased.

Cutaneous Squamous Cell Carcinoma: Updates in Staging and Management

Cutaneous squamous cell carcinoma (cSCC) is one of the most common cancers in the United States. Outcomes are generally favorable, but a subset of cSCC is biologically distinct and requires a different approach because of its higher risk of local recurrence, metastasis, and death. This article focuses on the recent literature regarding identification of this high-risk subset, efforts to validate and improve the prognostic ability of staging systems, and updates in management.

Basal cell carcinoma: Epidemiology; pathophysiology; clinical and histological subtypes; and disease associations

As the most common human cancer worldwide and continuing to increase in incidence, basal cell carcinoma is associated with significant morbidity and cost. Continued advances in research have refined both our insight and approach to this seemingly ubiquitous disease. This 2-part continuing medical education article will provide a comprehensive and contemporary review of basal cell carcinoma. The first article in this series describes our current understanding of this disease regarding epidemiology, cost, clinical and histopathologic presentations, carcinogenesis, natural history, and disease associations.

Validating the use of Medicare Australia billing data to examine trends in skin cancer

Background:  Epidemiological data surrounding non-melanomatous skin cancer (NMSC) is highly variable, in part due to the lack of government cancer registries. Several studies employ the use of Medical Australia (MA) rebate data in assessing such trends, the validity of which has not been studied in the past. Conversely, melanoma skin cancer is a notifiable disease, and thus, MA and cancer registry data is readily available. The aim of the current study is to assess the use of MA for epidemiological measures for skin cancers, by using melanoma as a disease sample.

Methods:  Following ethics approval, data from MA and Victorian Cancer Registry (VCR) from 2004-2008 were extracted. Incidence of MA and VCR unique melanoma cases were compared and stratified by age and local government area (LGA). Regression and a paired-samples t-test were performed.

Results: During the study period; 15,150 and 13,886 unique melanoma patients were identified through VCR and MA data sources respectively. An outlier in the >80­ year age group was noted between MA and VCR data. When stratified by age, significant correlation between MA and VCR was observed for all patients (gradient 0.91, R²= 0.936) and following exclusion of >80 patients (gradient 0.96, R²= 0.995). When stratified by LGA, a high degree of observation was observed for all patients (gradient 0.94, R²= 0.977) and following exclusion of >80 patients (gradient 0.996, R²= 0.975).

Conclusion: Despite the inclusion of outlier data groups, acceptable correlation between MA and VCR melanoma data was observed, suggesting that MA may be suitable for assessing epidemiological trends. Such principals may be used to validate the use of MA data for similar calculations assessing NMSC trends.

Incidence and prevalence of non-melanoma skin cancer in Australia: A systematic review

Non-melanoma skin cancer (NMSC), including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), is the most common cancer occurring in people with fair skin. Australia has been reported to have the highest incidence of NMSC in the world. Using a systematic search of the literature in EMBASE and Medline, we identified 21 studies that investigated the incidence or prevalence of NMSC in Australia. Studies published between 1948 and 2011 were identified and included in the analysis. There were six studies that were conducted on national level, two at state level and 13 at the regional level. Overall, the incidence of NMSC had steadily increased over calendar-years in Australia. The incidence of NMSC per 100,000 person-years was estimated to be 555 in 1985; 977 in 1990; 1109 in 1995; 1170 in 2002 and 2448 in 2011. The incidence was higher for men than women and higher for BCC than SCC. Incidence varied across the states of Australia, with the highest in Queensland. The prevalence of NMSC was estimated to be 2% in Australia in 2002. The incidence and prevalence of NMSC still need to be accurately established at both national and state levels to determine the costs and burden of the disease on the public health system in Australia.

Non melanoma skin cancer and subsequent cancer risk

INTRODUCTION

Several studies have shown an increased risk of cancer after non melanoma skin cancers (NMSC) but the individual risk factors underlying this risk have not been elucidated, especially in relation to sun exposure and skin sensitivity to sunlight.

PURPOSE

The aim of this study was to examine the individual risk factors associated with the development of subsequent cancers after non melanoma skin cancer.

METHODS

Participants in the population-based New Hampshire Skin Cancer Study provided detailed risk factor data, and subsequent cancers were identified via linkage with the state cancer registry. Deaths were identified via state and national death records. A Cox proportional hazard model was used to estimate risk of subsequent malignancies in NMSC patients versus controls and to assess the potential confounding effects of multiple risk factors on this risk.

RESULTS

Among 3584 participants, risk of a subsequent cancer (other than NMSC) was higher after basal cell carcinoma (BCC) (adjusted HR 1.40 [95% CI 1.15, 1.71]) than squamous cell carcinoma (SCC) (adjusted HR 1.18 [95% CI 0.95, 1.46]) compared to controls (adjusted for age, sex and current cigarette smoking). After SCC, risk was higher among those diagnosed before age 60 (HR 1.96 [95% CI 1.24, 3.12]). An over 3-fold risk of melanoma after SCC (HR 3.62; 95% CI 1.85, 7.11) and BCC (HR 3.28; 95% CI 1.66, 6.51) was observed, even after further adjustment for sun exposure-related factors and family history of skin cancer. In men, prostate cancer incidence was higher after BCC compared to controls (HR 1.64; 95% CI 1.10, 2.46).

CONCLUSIONS

Our population-based study indicates an increased cancer risk after NMSC that cannot be fully explained by known cancer risk factors.

40-year trends in skin cancer in British Columbia, Canada, 1973 to 2003

BACKGROUND

Skin cancer is common in North America. Incidence rate trends are potentially important in the assessment of the effects of measures to increase sun awareness in the population as well as measures to reduce sun damage.

OBJECTIVE

To determine the incidence of basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and cutaneous malignant melanoma (CMM) in a geographically defined Canadian population over a 40-year period.

METHODS

Data were obtained from the BC Cancer Registry for the calendar years 1973, 1983, 1993, and 2003.

RESULTS

Age-standardized incidence rates increased significantly from 1973 to 2003 for BCC, SCC, and CMM.

LIMITATIONS

The ethnic makeup of British Columbia has changed over time, and a novel method of accounting for the effect of this on skin cancer rates is presented.

CONCLUSION

The incidence rate for skin cancers continued to rise in British Columbia, but there appears to have been a decline in the incidence of CMM and BCC in the youngest cohorts.

A systematic review of worldwide incidence of nonmelanoma skin cancer

BACKGROUND

  Nonmelanoma skin cancer (NMSC) is the most common cancer affecting white-skinned individuals and the incidence is increasing worldwide.

OBJECTIVES

This systematic review brings together 75 studies conducted over the past half century to look at geographical variations and trends worldwide in NMSC, and specifically incidence data are compared with recent U.K. cancer registry data.

METHODS

Following the development of a comprehensive search strategy, an assessment tool was adapted to look at the methodological quality of the eligible studies.

RESULTS

Most of the studies focused on white populations in Europe, the U.S.A. and Australia; however, limited data were available for other skin types in regions such as Africa. Worldwide the incidence for NMSC varies widely with the highest rates in Australia [>1000/100, 000 person-years for basal cell carcinoma (BCC)] and the lowest rates in parts of Africa (< 1/100, 000 person-years for BCC). The average incidence rates in England were 76·21/100, 000 person-years and 22·65/100, 000 person-years for BCC and squamous cell carcinoma (SCC), respectively, with highest rates in the South-West of England (121·29/100, 000 person-years for BCC and 33·02/100, 000 person-years for SCC) and lowest rates by far in London (0·24/100, 000 person-years for BCC and 14·98/100, 000 person-years for SCC). The incidence rates in the U.K. appear to be increasing at a greater rate when compared with the rest of Europe.

CONCLUSIONS

NMSC is an increasing problem for health care services worldwide. This review highlights a requirement for prevention studies in this area and the issues surrounding incomplete NMSC registration. Registration standards of NMSC should be improved to the level of other invasive disease.

Topography of basal cell carcinoma and their correlations with gender, age and histologic pattern: a retrospective study of 1042 lesions

BACKGROUND

Basal cell carcinoma accounts for 75% of skin cancer. Sun exposure and genetics are related to its etiology. It's expected that biological and behavioral differences provide different patterns of involvement between sexes.

OBJECTIVES

To evaluate the topography of lesions and their correlations with gender, age and histological type.

METHODS

Retrospective study of basal cell carcinoma patients treated between 1999 and 2008 in the Skin Cancer Clinic of Santa Casa de Misericordia of Curitiba. We evaluated sex, age, location, histological type, margins commitment, sun exposure and family skin cancer history.

RESULTS

We found 1042 lesions in 545 patients (61% women), being more numerous in men (p<0.01). Their ages ranged between 27 and 95 years (median=65). Men had more sun exposure (p<0.01). The lesions were more frequent extra-cephalic recently (p<0.01). The margin involvement was higher in the head (p<0.01). The superficial type was less frequent on the head (p<0.01) and was associated with younger ages in women (p<0.01). The head housed 74% of lesions and the legs 2%. Women had a predilection for the legs, nose and upper lip and men to trunk, ears and scalp (p <0.05). The surgeries in the medial epicanthus and scalp occurred at younger ages (p=0.01).

CONCLUSIONS

We identified significant associations between the topography of lesions, gender, age and histological type, demonstrating the possible pathophysiological diversity and differential risk factors operation. In the period studied we found no trend of increase in the proportion of young or women among patients.

The relationship between basal and squamous cell skin cancer and smoking related cancers

Background

We compared the risk of being diagnosed with smoking-related cancers (lung, oral cavity, upper digestive and respiratory organs, bladder, kidney, anogenital cancers and myeloid leukaemia) among people with squamous cell carcinoma (SCC) or basal cell carcinoma of the skin (BCC), with risks found in the general population using data from an Australian population-based cancer registry.

Methods

People diagnosed with BCC or SCC in 1980-2003 reported to the Tasmanian Cancer Registry, Australia, were followed-up by linkage within the registry, until diagnosis of a subsequent smoking-related cancer, death, or until 31 December 2003. Risk of developing a future smoking-related cancer was assessed using age Standardised Incidence Ratios (SIR).

Results

People diagnosed with SCC had an increased risk of lung cancer (men: SIR = 1.89, 95% confidence interval: 1.61-2.21; women: SIR = 2.04, 1.42-2.83) and all other smoking-related cancers (men: SIR = 1.38, 1.19-1.60; women: SIR = 1.78, 1.34-2.33). Men with BCC had a significant increased risk of lung cancer (SIR = 1.26, 1.10-1.44) but not of any of the other smoking-related cancers (SIR = 1.09, 0.97-1.23).

Conclusions

Individuals with a history of SCC having an increased risk of developing smoking related cancers cancer suggests smoking as a common etiology. The relationship between BCC and smoking-related cancers is less certain.

Malignant eyelid tumors in Hong Kong 1997-2009

PURPOSE

To determine the epidemiologic and clinical characteristics of patients with malignant eyelid tumors in Hong Kong.

METHODS

A computerized retrieval system was used to identify all patients with histologically confirmed malignant eyelid tumors residing in Western Kowloon and the Southern New Territories, Hong Kong, during the 13-year period from 1997 to 2009. The patients' medical records were reviewed for clinical and demographic data.

RESULTS

A total of 36 patients were identified; all were Chinese. The mean age at diagnosis was 73.4 ± 11.5 years. Women were more commonly affected. Each patient had 1 tumor. Tumors developed more commonly on the lower eyelid (n = 19; 52.8%) than on the upper eyelid (n = 11; 30.6%). The right eye was more often involved (n = 20; 55.6%). With regard to the type of tumor, 27 were basal cell carcinoma (BCC) (75%), 4 sebaceous gland carcinoma (11.1%), 2 squamous cell carcinoma (5.6%), 1 mucinous eccrine carcinoma (2.8%), 1 verrucous carcinoma (2.8%), and 1 metastatic carcinoma (2.8%). Most were treated by frozen section-guided excision and eyelid reconstruction. Recurrence occurred in 1 case only. Incidence was low until approximately 45 years of age, after which it rose sharply. The incidence continued to increase until above the age of 85 years. There was an overall increase in incidence from 0.6 per million in 1997 to 2.3 per million in 2009.

CONCLUSION

Increasing incidence of malignant eyelid tumors was noticed in Hong Kong from 1997 to 2009, with BCC dominating the incidence trend. Recurrence after complete surgical excision was uncommon.

[Basal cell carcinoma of unusual site]

BACKGROUND

Labial mucosa is an atypical site of basal cell carcinoma. The involvement of the vermilion lip, devoid of hair follicles and sweat glands, contrasts with the concept of its origin from pilar structures. We report a case of basal cell carcinoma developed on the vermilion upper lip.

CASE REPORT

A 49-year-old woman, presented with an asymptomatic, 1-cm-diameter, erythematous, telangiectatic and crusted nodule on the upper lip evolving for 9 months and having once interested the vermilion border. There were no cervical lymph nodes. Diagnosis of infiltrative basal cell carcinoma was made by histological study, which showed a tumoral proliferation of epithelial basal cells infiltrating the dermis with perineural and muscular infiltration.

DISCUSSION

Our report illustrates a rare but not exceptional site of basal cell carcinoma. The nodule, initially confined to the vermilion border, has then developed onto the mucosal and the cutaneous areas. Histopathological study revealed, as previously reported, infiltarative features. Basal cell carcinoma of the lip should be rapidly managed since its invasion to deeper structures occurs early.

Metastatic cutaneous squamous cell carcinoma of the external ear: a high-risk cutaneous subsite

Introduction:

Patients with cutaneous squamous cell carcinoma of the external ear may develop metastatic spread to the nearby ipsilateral parotid and/or upper cervical lymph nodes. The literature suggests that the external ear is a high-risk subsite for such tumours, due to nodal metastasis and its associated morbidity and mortality.

Methods:

Between 1980 and 2007, 43 patients with a diagnosis of metastatic cutaneous squamous cell carcinoma of the external ear were treated with surgery alone, surgery plus adjuvant radiotherapy, or radiotherapy alone.

Results:

Patients comprised 39 men and four women. Their median age at diagnosis was 72 years, with a median follow up of 35 months. The median size of the primary lesion was 21 mm, with a median thickness of 7 mm. Fifteen patients presented concurrently with nodal metastases. Thirty patients developed parotid metastases (with positive cervical nodes in six patients), while 13 developed cervical metastases only. Eight patients underwent surgery alone, 32 underwent surgery plus adjuvant radiotherapy, and three received radiotherapy alone. At the last follow up, 15 patients had relapsed and nine had died of their disease, with a median survival after relapse of 5.5 months.

Conclusion:

Patients with metastatic cutaneous squamous cell carcinoma of the external ear have a relatively poor outcome, with a significant number of patients experiencing nodal relapse and death after treatment.

Incidence of nonmelanoma skin cancer in a cohort of patients with vitiligo

BACKGROUND

Nonmelanoma skin cancer (NMSC) incidence in patients with vitiligo has not been studied.

OBJECTIVE

We sought to quantify the incidence of NMSC in patients with vitiligo.

METHODS

A cohort of 477 patients with vitiligo and no history of NMSC seen in an outpatient academic center between January 2001 and December 2006 was established. All charts for patients with vitiligo were reviewed for incident NMSC, and histopathology verified. Age-adjusted (2000 US Standard Million) incidence rates were calculated and compared to US rates.

RESULTS

Six patients with NMSC were identified; all were Caucasian (>61 years). Age-adjusted incidence rates were: basal cell carcinoma, male 1382/100,000; basal cell carcinoma, female 0; squamous cell carcinoma, male 465/100,000; squamous cell carcinoma, female 156/100,000. Except for basal cell carcinoma in females, all rates were higher than US rates but not statistically significant.

LIMITATIONS

Comparison incidence rates from the general patient population during the same time period were unavailable.

CONCLUSION

Health care providers should be aware of the possible risk of NMSC in Caucasian patients with vitiligo.

Incidence of Eyelid Cancers in Taiwan

PURPOSE

To describe the epidemiologic characteristics and incidence trends of primary eyelid cancers in the Chinese population in Taiwan between 1979 and 1999.

DESIGN

Retrospective population-based cancer registry data review.

PARTICIPANTS

A total of 1166 primary eyelid cancers coded to International Classification of Diseases 8 or 9, site 172.1 (malignant melanoma of eyelid) and 173.1 (other malignant neoplasm of eyelid) were retrieved from the Taiwan National Cancer Registry between January 1979 and December 1999. Of these, 1121 (96.1%) were histopathologically verified and were used for analysis.

METHODS

Age- and gender-specific incidence rates were calculated and were age-adjusted to the 2000 world standard population. Trends in incidence rates were estimated by calculating the annual percentage change. We further examined the effects of age, period of diagnosis, and birth cohort on incidence trends using age-period-cohort analysis.

MAIN OUTCOME MEASURE

Age-standardized incidence rate.

RESULTS

The mean age at diagnosis of eyelid cancers was 62.6+/-14.1 years. The average annual age-standardized incidence rate was 3.2 per million during the study period. There was an overall increase of incidence rates from 1.5 per million in 1979 to 5.1 per million in 1999, with an annual percentage change of 4.63% (P<0.001). The most common eyelid malignancy was basal cell carcinoma (BCC; 65.1%), followed by squamous cell carcinoma (12.6%), and sebaceous cell carcinoma (7.9%). The increasing rates were mainly driven by an increase in the incidence of BCC. Cohort effects were found to play a major role in terms of model fit for the incidence trends of BCC.

CONCLUSIONS

These national data reveal a rapidly increasing incidence of eyelid cancers from 1979 to 1999 in Taiwan. Basal cell carcinoma dominates the incidence trends, and the significant cohort effects give a warning of increasing risk of BCC in younger birth cohorts.

High-risk non-melanoma skin cancer of the head and neck

High-risk non-melanoma skin cancer (NMSC) of the head and neck is difficult to manage, given its propensity for regional metastasis, perineural invasion, direct parotid invasion, and bony destruction. Management of these tumors demands awareness of the characteristics contributing to their recurrence. Recent studies emphasize the importance of treatment of the parotid gland and cervical lymph nodes to improve locoregional control. A multidisciplinary approach to the assessment and treatment of high-risk NMSC is required to provide comprehensive care. This review also covers recent advances in the understanding of NMSC biology and new approaches in chemoprevention.

Basal cell carcinoma: an updated epidemiological and therapeutically profile of an urban population

PURPOSE: To describe the epidemiological profile of basal cell carcinoma patients at a private hospital in São Paulo and to evaluate the treatment adopted. METHODS: A prospective study of 202 patients, on which 253 lesions were diagnosed for histopathological exam as basal cell carcinoma within the period of January 2001 to September 2003, in the Plastic Surgery Residency Program at the Hospital Jaraguá. The susceptibility factor of the host, the environment variables, the characteristics of the lesions and the efficacy of the treatment were examined. The data were statistically evaluated. RESULTS: The incidence of basal cell carcinoma was 126 cases per 100,000 patients in a period of 32 months (36 cases per 100,000 patients/year). The patients were evenly distributed in terms of sex: 48% male and 52% female. The greater incidence was in patients between the ages of 60 and 80 years and the average was 64 years. The survey revealed susceptibility factors such as white race and phototypes I and II in 95.5% of the patients. Exposition to ultraviolet radiation was reported by 77% of the patients and the most frequent location of tumors was on the face (71.2% of the cases). Actinic keratosis and a history of skin cancer were reported in 43.6% and in 25% of the cases, respectively. The adopted treatment was surgery in 99.4% of the cases and only one patient was treated with radiotherapy. Twenty lesions (8%) had incomplete excision.The recurrence rate was 2% (5 cases). There were no cases with metastasis or fatal outcome. CONCLUSIONS: The factors related to the development of basal cell cancer which were significantly present in the population surveyed were: older age, white individuals, phototypes I and II, presence of actinic keratosis, previous history of non-melanoma skin cancer and exposure to ultra-violet rays both in recreational and in occupational form.The surgical treatment employed was effective with a rate of incomplete excision and recurrence similar to those found in the literature.

Non‐melanoma skin cancer in Australia: the 2002 national survey and trends since 1985

OBJECTIVES

To measure the incidence of treated non-melanoma skin cancer (NMSC) in Australia in 2002 and investigate trends since 1985 by histological type, sex, age group, latitude and skin type.

DESIGN

Face-to-face survey between 1 January and 31 December 2002 using stratified sampling of households to identify people treated for skin cancer in the previous 12 months. Self-reported diagnoses were confirmed with treatment providers. Data from similar surveys conducted in 1985, 1990 and 1995 were used to assess trends.

SETTING

Whole of Australia (population 19.6 million).

PARTICIPANTS

Of 57 215 people interviewed, 4098 said they had been treated for skin cancer in the past year and 3198 gave permission for their diagnoses to be confirmed with their doctor.

RESULTS

817 people were confirmed as having at least one skin cancer treated in the past year. The age-standardised rate per 100 000 population for NMSC was 1170, for basal cell carcinoma (BCC) 884, and for squamous cell carcinoma (SCC) 387. The estimated number of NMSC cases in Australia for 2002 was 374 000. Cumulative risks to age 70 years of having at least one NMSC were 70% for men and 58% for women. Rates of BCC and SCC have increased since 1985, and the increases greatest for people aged 60 years and older; rates for those younger than 60 years have stabilised.

CONCLUSIONS

The incidence of treated NMSC in Australia in 2002 was more than five times the incidence of all other cancers combined. Although the overall NMSC rates have risen since 1985, the stabilisation of rates for people younger than 60 years who were exposed to skin cancer prevention programs in their youth highlights the importance of maintaining and strengthening these programs.

Trends of nonmelanoma skin cancer from 1960 through 2000 in a Canadian population

Nonmelanoma skin cancer (NMSC) is the most common malignancy diagnosed in Caucasian populations, but little is known about its occurrence in Canada. We sought to determine the historical change of the occurrence and risk of NMSC. All first diagnoses of NMSC reported in Manitoba between 1960 and 2000 were identified. Rates were reported as well as lifetime risk of developing the disease. Basal cell carcinoma was the predominant form of NMSC, accounting for 79% of all NMSCs. The annual percentage change of basal cell and squamous cell carcinoma increased 2.4%, mainly in people older than 40 years of age from the early 1970s to 2000. The lifetime risk of being diagnosed with NMSC increased by two to three times in the 1990s compared to the 1960s. We concluded that because of the potentially high impact of NMSC on resource utilization and treatment-related costs as well as its easily preventable character, priority should be given to prophylactic measures.

Basal Cell Carcinomas of the Eyelids

Basal cell carcinomas (BCC) are the more frequent malignant tumors seen in France as in other western countries. They represent 20% of eyelid tumors and 90% of eyelid malignancies. Due to their local growth, problems may arise when treating BCC, and curative exeresis must be the preferred choice each time it is possible. BCC of the eyelids have a high risk of recurrence. Recurrences are more aggressive, infiltrative and destructive and have a considerably poorer rate of cure than primary tumors. Eyelid reconstructions can entail use of complex methods which should only be carried out by a trained ophthalmologist who is also able to treat any associated age-related ocular pathologies. BCC is the most common cause leading to eyelid reconstructive surgery; a surgery which has a triple objective: tumor removal, functionality and an esthetic outcome.

Predictors of sun protection in northern Australian men with a history of nonmelanoma skin cancer

BACKGROUND

It is important to understand what predicts regular use of sun protection in men susceptible to skin cancer.

METHODS

A questionnaire survey of men with previous nonmelanoma skin cancer (n = 300) was conducted.

RESULTS

Participants who typically used sunscreen tended to be younger, have fewer excised skin lesions, work indoors, and have spent most of their life in the tropics. Predictors of wearing a long-sleeved shirt with a wide-brimmed hat were not enjoying sun exposure, not having barriers to using sun protection, having more skin lesions previously excised, working for a company with a mandatory policy of sun protection, attitudes that the benefits of a suntan do not outweigh the risks and that skin cancers cannot be easily treated, and age over 50.

CONCLUSIONS

Men who adequately protect themselves from the sun and who have better attitudes to sun exposure were more often those with a high level of negative experience with skin cancer. Therefore, the sun protection attitudes and behaviors of some men may only improve after significant sun damage. This study recommends that the use of appropriate sun protective clothing should be made mandatory for all who work outdoors in high-sun-exposure occupations.

Ultraviolet carcinogenesis in nonmelanoma skin cancer. Part I: incidence rates in relation to geographic locations and in migrant populations

Over the past two decades a worldwide increase in the incidence of skin cancer to near epidemic proportions has led to increased morbidity and appreciating cost. Well known risk factors include UV radiation, x or gamma irradiation, chemical carcinogens, genetic aberrations, and immunosuppression. This article reviews and analyzes the evidence for UV radiations role in the pathogenesis of nonmelanoma skin cancer (NMSC). Observations on the incidence of NMSC among migrants to temperate regions show an increase in both basal cell carcinoma and squamous cell carcinoma. There is also an increase in NMSC in areas with lower latitudes. Irradiation of human skin grafted to animals and animal models that develop NMSC lend further support to the role of UV radiation in the pathogenesis of NMSC. In the forthcoming Part II of this review, epidemiologic evidence will be presented attesting to the relationship between UV radiation and NMSC.

Epidemiology of skin tumors: data from the cutaneous cancer registry in Trentino, Italy

BACKGROUND

A Skin Cancer Registry was established in the province of Trento in northeast Italy in 1992 with the aim of collecting data on all cutaneous tumors affecting residents. These neoplasms are responsible for considerable morbidity and utilization of the Health Service because of their high frequency and, therefore, knowledge of the exact incidence is very important in planning health policies. Registry data are also very helpful in performing studies of analytical and descriptive epidemiology.

METHODS

For each patient, we collected personal data, phenotypical characteristics, professional history, concurrent diseases, previous therapy or trauma, and all data regarding the tumors. Patients were interviewed in person or, less frequently, by phone. All data were verified and put in a computerized file, in a protected room. The Statistics Institute of Trento University analyzed the data. Comparison among means was performed using the analysis of variance and differences among proportions were tested by chi-squared analysis. Poisson regression and the likelihood ratio test were used to compare incidence rates. We analyze here the data regarding epiteliomas and melanoma.

RESULTS

During the study period we registered 3435 primary skin tumors in 2868 individuals. Crude incidence rates, calculated using the number of subjects (not the number of tumors), were 87.9 for basal cell carcinoma (BCC), 28.9 for squamous cell carcinoma (SCC), and 14.2 for cutaneous melanoma (CM), per 100,000 per annum. We also calculated the same figures in females and males and specific incidence rates in both sexes and evaluated the distribution of skin cancer according to sex and anatomical site.

CONCLUSION

We report the analysis of the data collected by the Skin Cancer registry in a 6 year period and compare the data with published data in literature and with data of a previously registered melanoma file. Our results confirm the high incidence of nonmelanoma skin cancers and the variation in the histological patterns of CM.

Basal cell carcinoma, squamous cell carcinoma and melanoma of the skin: analysis of the Singapore Cancer Registry data 1968-97

BACKGROUND

There has been an alarming recent increase in skin cancer incidence among fair-skinned populations. Information from Asian populations is less readily available.

OBJECTIVES

This study examines time trends and ethnic differences of skin cancers among Asians in Singapore.

METHODS

Data from 1968 to 1997 was obtained from the Singapore Cancer Registry, a population-based registry. Age-standardized incidence rates (ASRs) and age-adjusted average annual percentage change, using the Poisson regression model, were calculated.

RESULTS

A total of 2650 basal cell carcinomas (BCCs), 1407 squamous cell carcinomas (SCCs) and 281 melanomas were reported. There was an overall increase of skin cancer from 6.0 per 100000 person years (1968-72) to 8.9 per 100000 person years (1993-97). BCC incidence increased 3% annually, melanoma remained constant, and SCC decreased 0.9% annually. BCC ASRs were highest among Chinese, then Malays and Indians. A similar pattern was noted for SCC and melanomas.

CONCLUSIONS

The incidence rates of skin cancer increased in Singapore during the period 1968-97. Fairer-skinned Chinese had a higher incidence of skin cancer.

Multiple nonmelanoma skin cancer in an exposed Australian population

BACKGROUND

Patients with nonmelanoma skin cancer (NMSC) frequently develop multiple skin cancers. The study presents incidence rates and rates of excision of NMSC for a population living in a high-risk environment for skin cancer.

METHODS

Between 1997 and 1999 a prospective population-based study collected information on all histologically confirmed NMSCs in Townsville, Australia.

RESULTS

Of the 6708 patients recorded with NMSC, 38.5% had multiple lesions. Yearly age-standardized incidence rates (per 100,000 inhabitants) of basal cell carcinoma (BCC) were 1444.8 for men, 942.7 for women, and of squamous cell carcinoma (SCC) were 805.0 for men, and 423.6 for women. Compared to incidence rates, age-standardized rates of lesions of BCC were 2.1 times higher in men, 1.6 times higher in women, and of SCC were 1.8 times higher in men and 1.4 times higher in women.

CONCLUSIONS

The occurrence of multiple NMSCs compromises results of short-term studies on incidence. Further discussions on the most appropriate strategies to describe the real burden of NMSC are warranted.

Sun-related behaviors of outdoor working men with a history of non-melanoma skin cancer

The present study describes sun exposure and sun protection behaviors of northern Australian outdoor workers with previous non-melanoma skin cancer (NMSC). In 1999 a cross-sectional study of northern Australian men with previous NMSC was conducted by self-administered questionnaire. Compared to other men, outdoor workers spent more time in the sun on average working days and days off (P < 0.0001, respectively), and outdoor workers with sun-sensitive skin reported that more skin lesions had been removed (P = 0.0461). The workplace did not reinforce sun-safe practices of 36.8% of workers who spent half their time or more outdoors. Sun-protective behaviors were not different between in- and outdoor workers. Outdoor workers experienced high levels of sun exposure, however, sun-protective behavior was similar to other workers. Workplaces should be targeted to reinforce sun-safe policies.

The epidemiology of skin cancer

Melanoma and non-melanoma (basal and squamous cell carcinoma) skin cancer (NMSC) are now the most common types of cancer in the white populations and the incidence of skin cancer has reached epidemic proportions. According to recent population-based studies from Australia the incidence rate is over 2% for basal cell carcinoma in males and 1% for squamous cell carcinoma, and there are over 50 new cases of melanoma per 100 000.

Basal cell carcinoma of the lip treated with radiotherapy

Basal cell carcinoma (BCC) of the lip is uncommon relative to other cutaneous sites for BCC, such as the central face or scalp. A female predisposition and predilection for the upper lip have been previously documented. A retrospective analysis of patients treated for BCC of the lip was undertaken within the department of Radiation Oncology, Westmead Hospital, Sydney. Twenty patients were identified; 12 women and 8 men. The majority (15/20) had T1 lesions of the upper lip (17/20). Eleven patients were referred for radiotherapy alone and nine for adjuvant radiotherapy following either incomplete excision or local recurrence. With a mean follow up of 36 months no patient has recurred following either definitive or adjuvant radiotherapy. Despite the majority of BCCs of the lip being amenable to surgery fractionated external beam radiotherapy remains an option especially when functional and/or cosmetic concerns are an issue. We present the findings from this small case series and use our findings to illustrate the role of radiotherapy in treating BCC of the lip.

Non-melanoma skin cancers and glucocorticoid therapy

Non-melanoma skin cancer (NMSC) is an important cause of morbidity and long-term mortality in organ transplant recipients receiving immunosuppressive drugs such as azathioprine and cyclosporin, often combined with adrenocortical steroids (glucocorticoids). At lower doses, glucocorticoids alone are prescribed for other conditions including musculoskeletal, connective tissue and respiratory disorders. Presently, it is unknown whether patients taking glucocorticoids are at an increased risk of skin malignancies. In a population-based case-control study in New Hampshire, USA, we compared use of glucocorticoids in 592 basal cell carcinoma (BCC) and 281 squamous cell carcinoma (SCC) cases and in 532 age and gender matched controls; neither cases nor controls had a history of organ transplantation. Participants underwent a structured personal interview regarding history of medication use and skin cancer risk factors. We used unconditional logistic regression analysis to compute odds ratios associated with glucocorticoid use for 1 month or longer while controlling for potential confounding factors. Risk of SCC was increased among users of oral glucocorticoids (adjusted odds ratio = 2.31; 95% CI = 1.27, 4.18), and risk of BCC was elevated modestly (adjusted odds ratio = 1.49; 95% CI = 0.90, 2.47). In contrast, risk of both SCC and BCC were unrelated to use of inhaled steroids. Our data suggest that use of oral glucocorticoids may increase risk of NMSC, and SCC in particular, among patients other than organ transplant recipients. We hypothesize that immunosuppression induced by oral glucocorticoids may allow these cancers to emerge from immunosurveillance.

Descriptive epidemiology of skin cancer on Aruba: 1980-1995

BACKGROUND

An epidemiology unit was established in Aruba in 1994. The primary focus was the development of an infrastructure for both surveillance and health information data systems. This effort resulted in the first analysis of available skin cancer data.

METHODS

A retrospective study of cancer and particularly skin cancer cases at the local histopathology laboratory for the period 1980-1995 was performed. All available records with a cancer diagnosis were evaluated.

RESULTS

During the study period, an increase in age-adjusted rates for both men and women was observed for basal cell carcinomas and squamous cell carcinomas. No temporal trend was discerned for malignant melanoma or other skin cancers because the numbers of cases were small. Lesions were most often seen on the nose, face, and arm. Dermatologists provided the majority of skin cancer diagnoses and demonstrated the greatest diagnostic accuracy.

CONCLUSIONS

The presence of a central histopathology laboratory may provide small island states, like Aruba, with important public health data. This first description of Aruba's skin cancer epidemiology provides information that may be utilized for future public health action.

Changing trends in non-melanoma skin cancer in South Wales, 1988-98

BACKGROUND

In 1988 our department carried out a population-based epidemiological study of non-melanoma skin cancer (NMSC) incidence, over a 6-month period, in West Glamorgan, South Wales. Objectives To reassess the incidence of NMSC in this defined population over a similar 6-month period 10 years after the initial study.

METHODS

All cases of basal cell carcinoma and squamous cell carcinoma diagnosed in West Glamorgan are recorded by the local skin cancer registry. All cases for the relevant 6-month period were analysed.

RESULTS

Using these figures, we have identified a significant rise in the crude incidence of NMSC from 173.5 10 years ago to 265.4 per 100,000 population per annum. We also applied the world standard population for age to our crude figures, demonstrating a combined male and female world population-corrected rate of 129.9 per 100,000 population.

CONCLUSIONS

In our population the crude incidence of NMSC has risen significantly over 10 years. Additionally, the combined male and female world population-corrected rate appears to be the highest published standardized incidence of NMSC to date from any European country.

Sunscreens and cutaneous malignant melanoma: an Italian case-control study

The possible relation between use of sunscreens and the risk of cutaneous malignant melanoma (CMM) was investigated in a case-control study conducted in 27 Italian centres on 542 incident, histologically confirmed cases and 538 controls admitted for acute, other than neoplastic or dermatologic conditions. Compared with subjects reporting never sunscreen use, the multivariate odds ratios (OR), after allowance for age, sex, geographic area, education, skin, eye and hair colour, freckles, number of naevi, history of sunburns, tanning pattern and duration of sunny vacations, were 0.97 (95% confidence interval [CI] 0.69 to 1.35) for those reporting "sometimes" and 0.80 (95% CI 0.54 to 1.17) for those reporting "often " sunscreen use. With reference to type of product most frequently used, the ORs were 0.96 (95% CI 0.52 to 1.77) for minimal, 0.90 (95% CI 0.63 to 1.28) for moderate and 1.41 (95% CI 0.85 to 2. 35) for high sunburn protection factor. With reference to duration of use, the OR was 0.86 (95% CI 0.58 to 1.29) for use started since >/=20 years. None of the corresponding trends in risks were significant. The ORs for sunscreen use were similar across strata of major identified covariates and, if anything, tended to decline after multivariate analysis. The present findings confirm that sunscreen use, as currently adopted in Italy, is not appreciably related to subsequent CMM risk.

Histologic subtyping and malignancy assessment of cutaneous squamous cell carcinoma

BACKGROUND

Squamous cell carcinomas (SCCs) of the skin have a wide range of histologic subtypes and there are indications of differences in prognosis.

OBJECTIVE

The morphologic variety of SCCs with respect to its biological behavior and the further course of disease is analyzed, with emphasis on histopathologic criteria, briefly quoting the main clinical and pathogenetic aspects.

METHODS

Referring to the international tumor classification of the World Health Organization, histologically different carcinoma variants are presented and discussed, based on a review of the literature regarding each subtype, and also including the desmoplastic SCC type.

RESULTS

Histologically, common invasive SCCs are most frequently found, while metastases mainly occur in tumors of high thickness and poor differentiation. The immature spindle cell carcinoma type resembles sarcoma and may grow rapidly with an aggressive clinical course. Lymphoepithelioma-like carcinoma of the skin is extremely rare and its histogenesis remains to be elucidated. Thus far, one case with metastasis and lethal outcome has been reported. As details determining the progression ability have so far only been scanty and partially contradictory, more investigations are necessary, especially for acantholytic SCCs and invasive SCCs developing from Bowen's disease, whereas verrucous carcinomas can be categorized as low malignancy neoplasms. Desmoplastic SCCs, especially with large tumor thickness, should be separated from other SCC subtypes due to their high risk of local recurrence and metastatic spread.

CONCLUSION

The future outcome of SCCs of the skin is significantly influenced by their histologic grade and tumor thickness. In addition, subtyping represents another valuable histopathologic tool for improving the assessment of malignancy.

Trends for invasive squamous cell neoplasia of the skin in Norway

Over the period 1966-1995, based on 11,662 patients, the incidence of squamous cell carcinoma of the skin increased three to four times in Norway mainly as a result of an increased number of localized tumours. In men, cancer of the auricle was the second most common site; in women the incidence was low.

Increase in incidence rates of basal cell and squamous cell skin cancer in New Hampshire, USA. New Hampshire Skin Cancer Study Group

We conducted a study to estimate the current incidence rates of basal-cell carcinoma (BCC) and squamous-cell carcinoma (SCC) of the skin in the population of New Hampshire (NH), USA, and to quantify recent changes in the incidence rates of these malignancies. BCCs and SCCs diagnosed among NH residents were identified through physician practices and central pathology laboratories in NH and bordering regions from June 1979 through May 1980 and from July 1993 through June 1994. For each diagnosis period, we estimated the age-adjusted incidence rates for both BCC and SCC among both men and women and for separate anatomic sites. Between 1979-1980 and 1993-1994, incidence rates of SCC increased by 235% in men and by 350% in women. Incidence rates of BCC increased by more than 80% in both men and women. While the absolute increase was greatest for tumors of the head and neck, the relative change was most pronounced for tumors on the trunk in men and on the lower limb in women. Thus, there has been a marked rise in the incidence rates of BCC and SCC skin cancers in NH in recent years. The anatomic pattern of increase in BCC and SCC incidence is consistent with an effect of greater sunlight exposure. Studies of BCC and SCC occurrence are needed to identify possible behavioral and environmental factors and to assess possible changes in diagnostic practices that might account for the rise in incidence of these common malignancies.

Incidence rates of skin cancer in Townsville, Australia

Worldwide, incidence rates of skin cancer are increasing alarmingly in populations of predominantly Caucasian origin. A prospective population-based survey, set up to collect epidemiological information on all excised and histologically confirmed skin cancers, started in Townsville, Australia (population of 127,000) in December 1996. Data on the anatomical distribution of skin cancer has been collected using a detailed body map. Estimations of type-specific and site-specific incidence rates were age-standardized according to world standard population. Site-specific incidence rates were adjusted for surface proportion of the body site and are given per 100,000 body units. Between December 1996 and December 1997, a total of 3,536 patients with 5,945 histologically confirmed skin cancer lesions were recorded. Age-standardized incidence rates of basal cell carcinoma were 2,058.3 for men and 1,194.5 for women, 1,332.3 for men and 754.8 for women for squamous cell carcinoma, and 49.1 for men and 41.7 for women for cutaneous melanoma (CM). Site-specific incidence rates of non-melanocytic skin cancer were extreme on sun-exposed areas of the face, whereas site-specific incidence rates of CM were highest for neck, posterior trunk and face. Less exposed body sites, such as unexposed upper limbs or thighs, showed reduced incidence rates for all types of skin cancer. Tropical North Queensland has the world's highest incidence rates of skin cancer of all types. Site-specific incidence rates demonstrate that highly sun-exposed body sites are at high risk of developing skin cancer and provide, therefore, strong indirect evidence for the causal relationship between sun exposure and skin cancer.

Assessing incidence rates and secular trends in nonmelanocytic skin cancer: which method is best?

BACKGROUND

Evaluating the incidence of nonmelanocytic skin cancers in white populations and assessing the direction and strength of secular trends in these cancers have become important issues to dermatologists, oncologists, health policy analysts, and health care funders.

OBJECTIVE

The objective of this paper is to evaluate the three principal methods used to assess incidence rates and secular trends.

CONCLUSIONS

Each of the three methods has strengths and weaknesses. An understanding of these will enable proper assessment of the value and significance of findings presented in the literature.