Basal Cell and Squamous Cell Skin Cancers Guidelines

Basal cell and squamous cell skin cancers, collectively known as non-melanoma skin cancers (NMSCS), are the most common skin cancers. More than 1 million cases of NMSC are estimated to be diagnosed each year in the United States and their incidence is rising rapidly. Although rarely metastatic, basal cell and squamous cell cancers can produce substantial local destruction and disfigurement and may involve extensive areas of soft tissue, cartilage, and bone. Updates in the 2007 guidelines include changes to the principles of treatment for both basal cell and squamous cell skin cancers and changes in the consideration of radiotherapy.

For the most recent version of the guidelines, please visit NCCN.org

Arc welding and the risk of cancer

CASE STUDY

Mrs LF, 71 years of age, presents with numerous squamous cell carcinomas (SCCs) on her hands (Figure 1). She comments that she had 'perfect' hands until recent years and had never been an 'outdoors person'. On questioning her about trauma or exposure to her hands she commented that she had frequently experienced 'sunburn' on her hands after assisting her son with his welding business.

Risk Factors for Histological Types and Anatomic Sites of Cutaneous Basal-Cell Carcinoma: An Italian Case–Control Study

Different clinico-pathologic subtypes and anatomic sites of basal-cell carcinoma (BCC) may display distinct characteristics and mechanisms of development. However, scanty information exists on potential differences in etiological factors for BCC according to histotype and anatomic location. Thus, we analyzed data from an Italian case-control study, including 528 subjects with newly diagnosed, histologically confirmed BCC and 512 controls admitted to the same hospitals with acute conditions. The multivariate odds ratio (OR) of nodular (OR=1.53) but not superficial (OR=0.71) BCC was increased for occupational exposure to sunlight. Considering the anatomic site of BCC, the corresponding values were 1.46 for head/neck and 0.74 for truncal location. Direct associations were observed with recreational sunlight exposure, eye color, red hair, and number and early age of severe sunburn episodes, along with some differences in risk between histotypes and anatomic sites. This study confirmed the role of (intermittent) sun exposure and phenotypic characteristics as risk factors for BCC, and suggested etiological differences between nodular and superficial histotypes and between head/neck and truncal locations.

Treatment of a patient with epidermodysplasia verruciformis carrying a novel EVER2 mutation with imiquimod

Epidermodysplasia verruciformis (EV) is a rare disorder characterized by widespread human papillomavirus infection and malignant transformation. EV may be caused by mutations of the genes EVER1 or EVER2, which are located on the EV1 locus, 17q25. We describe a patient with EV and a novel homozygous gene mutation of EVER2 gene who was treated successfully with topical imiquimod.

Basal cell carcinoma on the trunk is associated with excessive sun exposure

BACKGROUND AND OBJECTIVE

Basal cell carcinoma (BCC) is the most common of all cancers. Ultraviolet radiation is the major etiologic agent in the pathogenesis of BCC, but there is not a straightforward relationship between cumulative exposure and risk. A high proportion of lesions arise on the trunk, which is generally much less exposed to the sun than the head, the major site affected. We tested the hypothesis that the phenotypic determinants and patterns of sun exposure that give rise to BCC on the head and trunk vary in a way that explains the anomalous site distribution.

METHODS

The study was set in the context of the Nambour Skin Cancer Study, a community-based follow-up study among 1621 participants with virtually complete ascertainment of BCCs between 1992 and 2004. We compared phenotypic and sun exposure characteristics of participants who developed a first BCC of the head or trunk with those of participants who had no diagnosis of BCC.

RESULTS

BCCs of the trunk were more likely to occur in men; they also occurred at a younger age than BCCs of the head. There was a positive association between sun sensitivity and BCC of the head that was absent for BCC of the trunk. A high number of solar keratoses conferred a greater than 3-fold risk for BCCs of both the head and the trunk. BCCs of the trunk had a particularly strong association with the number of reported sunburns and solar lentigines on the trunk, whereas many lentigines conferred a greater than 3-fold risk of truncal BCC compared with a 50% increased risk of BCC of the head.

LIMITATIONS

The relatively small numbers of tumors may have limited our ability to detect statistically significant differences.

CONCLUSIONS

BCCs of the trunk are the result of overexposure of the sensitive basal cells of the epidermis to ultraviolet radiation. This may result from acute intense exposures sufficient to cause sunburn among people whose ability to tan makes the skin of their face generally less susceptible to the carcinogenic effects of ultraviolet radiation.

A comparison of sunlight exposure in men with prostate cancer and basal cell carcinoma

Ultraviolet radiation exposure increases basal cell carcinoma (BCC) risk, but may be protective against prostate cancer. We attempted to identify exposure patterns that confer reduced prostate cancer risk without increasing that of BCC. We used a questionnaire to assess exposure in 528 prostate cancer patients and 442 men with basal cell carcinoma, using 365 benign prostatic hypertrophy patients as controls. Skin type 1 (odds ratio (OR)=0.47, 95% CI=0.26–0.86), childhood sunburning (OR=0.38, 95% CI=0.26–0.57), occasional/frequent sunbathing (OR=0.21, 95% CI=0.14–0.31), lifetime weekday (OR=0.85, 95% CI=0.80–0.91) and weekend exposure (OR=0.79, 95% CI=0.73–0.86) were associated with reduced prostate cancer risk. Skin type 1 (OR=4.00, 95% CI=2.16–7.41), childhood sunburning (OR=1.91, 95% CI=1.36–2.68), regular foreign holidays (OR=6.91, 95% CI=5.00-9.55) and weekend (OR=1.17, 95% CI=1.08–1.27) but not weekday exposure were linked with increased BCC risk. Combinations of one or two parameters were associated with a progressive decrease in the ORs for prostate cancer risk (OR=0.54–0.25) with correspondingly increased BCC risk (OR=1.60–2.54). Our data do not define exposure patterns that reduce prostate cancer risk without increasing BCC risk.

Impact of some constitutional characteristics on the development of basal cell carcinoma

Background/Aim. Basal cell carcinoma (BCC) is the most common form of skin cancer in the white population. Increasing incidence of BCC imposes the requirement to identify the risk factors due to eventual preventive action. The aim of this study was to assess the role of some constitutional characteristics in development of BCC among the Montenegrin population. Methods. A case-control study was conducted at the Dermatology Department of Clinical Center of Montenegro in Podgorica from 2002?2003. The study group included 100 histopatologically confirmed BCC cases, while the control group consisted of 100 patients from the same department, who did not present skin cancer and who were individually matched to the cases by sex and age (?5 years). All participants were interviewed using an epidemiological questionnaire. For statistical analysis t test and McNemar ?2 test for matched pairs and multivariate logistic regression analyses were used. Results. The risk for development of BCC was increased among the persons with lighter hair color (t = 4.63; df = 99; p < 0.001), fair skin (t = 2.37; df = 99; p = 0.020), lighter eyes color (t = 2.86; df = 99; p = 0.005), with nevuses (OR = 13.13; p = 0.025; 95% IP = 1.39-12.03), and among those whose skin tone after sun exposure remained light (OR = 3.14; p = 0.001; 95%IP = 1.59-6.18). Conclusion. Our study confirmed the significance of constitutional characteristics such as lighter hair color, fair skin, lighter eyes color, and the presence of nevuses in the development of BCC. .

Epidermal malignant tumors: pathogenesis, influence of UV light and apoptosis

Basal cell carcinoma and squamous cell carcinoma, collectively termed non-melanoma skin cancers are the most common malignant tumors in humans. Basal cell carcinoma grows slowly and metastatic spread is very rare. Squamous cell carcinoma is characterized by infiltrative, destructive growth and metastasis. Long-term exposure of skin to UV light has a great impact on development of these epidermal malignancies. UV light induces cascade of events like well known DNA damage of keratinocytes as well as still completely undetermined influence on apoptotic process through expression of proapoptotic and antiapoptotic molecules. The major role in development of skin cancer is given to proapoptotic p53 molecule or tumor suppressor gene which mutation due to UV exposure leads to resistance of DNA-damaged cell to apoptosis. Other proapoptotic molecules such as Fas ligand (FasL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) are strongly expressed in basal cell carcinoma and squamous cell carcinoma that could be explained by the ability of tumor to escape the attack of immune system.

Genetic factors in the pathogenesis of UV-induced skin cancer1

UV light exposure has been incriminated for the steady rise in skin cancer incidence observed during the last years. However, individual responses to the oncogenic effects of UV light are greatly variable. Among the many factors modulating the response to UV light, genetic variations play a pivotal role. This review examines major progress in our understanding of major hereditary and nonhereditary genetic modifiers involved in the pathogenesis of UV-induced skin cancer.

Cutaneous manifestations in renal failure patients: A case series

Cutaneous involvement in renal disease is due to a host of factors ranging from metabolic disturbances to immunosuppressive drugs. Herein we report a series of six cases of renal failure with varied cutaneous manifestations ranging from infections to neoplasms due to prolonged immunosuppression. Our first case had cutaneous cryptococcosis where skin lesions gave a clue to the diagnosis of altered sensorium and underlying meningitis. The second case initially presented with florid warts and was treated successfully but later presented with an explosive recurrence of skin lesions due to malignant transformation. Our third case had basal cell carcinoma over the presternal region that was successfully treated with liquid nitrogen cryotherapy. Our fourth case had diabetic nephropathy that presented with septicemia and purpura fulminans. The last case had cutaneous manifestations of drug therapy because of heparin infusion. To conclude, cutaneous manifestations in patients with renal failure are varied and a high degree of suspicion is needed for early diagnosis and aggressive treatment to effectively combat mortality and morbidity.

The Australian Mohs database: short-term recipient-site complications in full-thickness skin grafts

BACKGROUND

There are only a few reports on the outcome with full-thickness skin grafts (FTSG) in defect reconstruction after Mohs micrographic surgery (MMS).

OBJECTIVES

The objective was to evaluate the complications with FTSG in patients treated with MMS for cutaneous tumors.

METHODS

This study is based on a prospective data collection of all patients in Australia treated with MMS and monitored by the Skin and Cancer Foundation, between 1993 and 2002. Primary outcome measures were FTSG recipient-site complications (partial/complete graft failure, graft infection, acute bleeding/hematoma, graft hypertrophy, and graft contracture).

RESULTS

The study group included 2,673 patients (50.2% men) with a mean age of 64+/-14 years. Most tumors were basal call carcinoma (90.9%) and were located on the nose (63.8%), periocular area (14.8%), or auricular area (8.1%). A total of 11.7% of cases had recipient-site complications (graft hypertrophy, 42.3%; partial graft failure, 27.2%; graft contraction, 15.3%). Only 45.2% of complicated cases required treatment.

CONCLUSION

Short-term recipient-site complications occurred in less than 12% of reconstructions with FTSG. Graft hypertrophy and partial graft failure accounted for most cases of complications. The authors have indicated no significant interest with commercial supporters.

Scalp tumors treated with Mohs micrographic surgery: clinical features and surgical outcome

BACKGROUND

There are only a small number of reports on the outcome of scalp tumors treated with Mohs micrographic surgery (MMS).

OBJECTIVE

The objective was to present a large series of patients with scalp tumors treated with MMS in Australia between 1993 and 2002.

METHODS

This prospective, multicenter study included all patients with scalp tumors who were monitored by the Skin and Cancer Foundation Australia. The variables analyzed were patient demographics, reason for referral, preoperative tumor size and postoperative defect size, recurrences before MMS, histologic subtypes, perineural invasion, and 5-year recurrence.

RESULTS

The study included 316 patients (68% men) with a mean age of 65+/-15 years. The most common tumors were basal cell carcinoma (BCC), 57.9%; squamous cell carcinoma (SCC), 35.8%; Bowen's disease (BD), 4.1%; and atypical fibroxanthoma (AFX), 1.6%. Recurrent tumors comprised 37% of cases. The recurrence rate for 70 BCC patients who completed the 5-year follow-up was 5.7%, and for 31 SCC cases it was 3.2%. No cases of recurrence were noted in the patients with BD and AFX.

CONCLUSION

BCC was the most common scalp tumor managed by MMS. The low 5-year recurrence rate emphasizes the importance of margin controlled excision of scalp tumors.

[The relationship between the ozone layer and skin cancer]

In the recent decades, a sustained increase in the worldwide incidence of skin cancer has been observed and Chile is not the exception. The most important risk factor is the exaggerated and repeated exposure to ultraviolet radiation coming from the sun. The ozone layer restricts the transmission of type B and C ultraviolet light. Since 1980, a sustained depletion of stratospheric ozone levels is occurring, specially in middle latitudes (-30 to -60). Along with this depletion, the amount of ultraviolet light that reaches the earth surface is increasing. This article reviews some basic concepts about the ozone layer and the association between its depletion and skin cancer. The general population should be informed about the risks of inadequate and exaggerated exposure to sunlight.

Estimation of cancer risks from radiotherapy of benign diseases

BACKGROUND

The effective-dose method which was proposed by the ICRP (International Commission of Radiation Protection) for the estimation of risk to the general population from occupational or environmental, low-dose radiation exposure is not adequate for estimating the risk of cancer induction by radiotherapy of malignant or nonmalignant diseases.

METHODS

The risk of cancer induction by radiotherapy of benign diseases should be based on epidemiologic data directly derived from follow-up studies of patients who had been given radiotherapy for nonmalignant diseases in the past.

RESULTS

Risk factors were derived from epidemiologic studies of patients treated with irradiation for nonmalignant diseases to be used for selecting treatment options and optimizing treatment procedures.

CONCLUSION

In most cases, cancer risks estimated by the effective-dose method may overestimate the true risks by one order of magnitude, yet in other cases even may underestimate it. The proposed method using organ-specific risk factors may be more suitable for treatment planning.

Difference between pigmented and nonpigmented basal cell carcinoma treated with Mohs micrographic surgery

BACKGROUND

There have been several articles characterizing cases of pigmented basal cell carcinomas (PBCC). Previous studies have also evaluated the relationship between histologic pattern and frequency of basal cell carcinoma (BCC) associated with pigment formation. No specific studies, however, have examined the subclinical extension and surgical margins of PBCC tumors.

OBJECTIVE

A prospective study of 345 Mohs micrographic BCC surgical cases revealed 67 PBCC cases. Analysis of patient details included patient age and sex, the lesional site, histologic subtype, tumor size, final surgical margin, and the number of stages required to achieve tumor-free margins together with the presence or absence of pigment.

METHODS

This study was performed between May 2004 and January 2005 at the Department of Dermatology and Cutaneous Surgery, University of Miami, Mohs Surgery Center.

RESULTS

Total mean surgical margin was smaller in the PBCC than the nonpigmented BCC (NPBCC) group (3.89 mm vs. 5.85 mm; p<0.05). In lesions less than 2 cm in size, there were even more significant differences between the two groups (3.32 mm vs. 5.33 mm; p<0.05), and also between the aggressive and nonaggressive histologically diagnosed groups (3.13 mm vs. 5.01 mm; p<0.05).

CONCLUSIONS

We have demonstrated that PBCC requires a smaller surgical margin for complete tumor excision than NPBCC, especially in smaller tumors and in the nonaggressive histologic subtype group. Treatment within the early growth stages also involves less subclinical microscopic invasion and a smaller surgical margin in PBCC.

Basal cell carcinoma of the nose requiring amputation arising after irradiation for childhood hemangioma

A 49-year-old female, who had undergone irradiation at six years of age as a treatment for a cutaneous nasal hemangioma, developed later a devastating basal cell carcinoma requiring sub-amputation of the nose and subsequent reconstruction with a pre-expanded forehead flap. Basal cell carcinomas are now frequently reported as late sequelae of previous low-dose irradiations after 10-20 years, and patients should be aware of this possible evolution.

Characteristics of basal cell carcinoma amongst Asians in Singapore and a comparison between completely and incompletely excised tumors

BACKGROUND

Most published series of basal cell carcinomas (BCCs) are based on Caucasian populations. Very little is known about the characteristics of incompletely excised BCCs in Asians.

OBJECTIVES

This study examines the characteristics of BCCs in Asian residents in Singapore, and compares incompletely with completely excised tumors after conventional surgical excision.

PATIENTS AND METHODS

A retrospective study was conducted using the case records of patients who had a primary BCC excised at the National Skin Centre between 1991 and 1995.

RESULTS

A total of 185 histologically confirmed BCCs were recorded in 166 patients (male to female ratio, 0.95; mean age, 70.9 years). The highest proportion (27.1%) was in the 81-90-year age group. Compared with census data, a significantly higher proportion of patients with BCCs were Chinese (P < 0.001). The tumors averaged 12.0 mm in diameter and the majority (84.3%) were located on the head and neck. In 28 lesions (15.1%), the tumors were incompletely excised, with those on the nose and nasolabial folds being most frequent. Incompletely excised BCCs were more likely than completely excised lesions to be located on the mid-face and trunk (P = 0.003), but there was no significant correlation with tumor size, tumor duration, or patient age, race, and gender. The overall recurrence rate was 1.6% over a mean follow-up time of 74 months.

CONCLUSIONS

BCCs are more common amongst Chinese in Singapore and occur chiefly in the elderly. Conventional surgical excision with margin control achieves a satisfactory tumor clearance rate of 84.9%. Incomplete excision is associated with tumor location on the mid-face and trunk rather than tumor size or duration.

Hedgehog signalling in skin development and cancer

Basal cell carcinoma (BCC) is the most common human malignancy, affecting 750,000 Americans each year. The understanding of mutations that are known to activate hedgehog (Hh) signalling pathway genes, including PATCHED (PTCH), sonic hedgehog (Shh) and smoothened (Smo), has substantially expanded our current understanding of the genetic basis of BCC development. The Hh signalling pathway is one of the most fundamental signal transduction pathways in embryonic development. In skin, the Shh pathway is crucial for maintaining stem cell population, and for regulating hair follicle and sebaceous gland development. This pathway plays a minimal role in adult tissues, but is known to be activated in many neoplasms, including those arising in the skin. In this review, we attempt to summarize the results of published studies on some important aspects of the Shh pathway and its involvement in skin development and carcinogenesis. We also provide a description of various animal models that have been developed, based on our knowledge of the Shh pathway in human skin cancers. Additionally, we include a brief description of studies conducted in our laboratory and by others on the chemoprevention of BCCs. This review therefore provides a current understanding of the role of the Shh pathway in skin development and neoplasia. It also provides a basis for the molecular target-based chemoprevention and therapeutic management of skin cancer.

Dermoscopy Patterns of Fibroepithelioma of Pinkus

BACKGROUND

Fibroepithelioma of Pinkus (FeP) is a rare variant of basal cell carcinoma that may clinically mimic a number of benign skin tumors. While the dermoscopic features of basal cell carcinoma have been studied extensively, little is known about the dermoscopic features of FeP.

OBSERVATIONS

Retrospective evaluation of clinical records and digital clinical dermoscopic images of 10 histopathologically proved FePs (6 nonpigmented and 4 pigmented) was performed. Clinically, no FeP was correctly identified and, in half of all patients, a clinical differential diagnosis of purely benign skin lesions was made. Dermoscopy enabled the correct diagnosis in 9 of 10 FePs, based on the presence of fine arborizing vessels, either alone or associated with dotted vessels, and white streaks (in 100%, 70%, and 90% of lesions, respectively). In the 4 pigmented FePs, a structureless gray-brown area of pigmentation and variable numbers of gray-blue dots were observed, in addition.

CONCLUSIONS

Dermoscopy is helpful in diagnosing FeP and in differentiating this variant of basal cell carcinoma from other benign skin tumors commonly included in the clinical differential diagnosis. This presumes, however, that dermoscopy is used as a first-line examination for all skin lesions, not only for those that are clinically suspect.

[Profile of basal cell carcinomas of the scalp after radiotherapy for tinea capitis (about 63 cases)]

The induction of basal cell carcinoma (BCC) of the scalp by X-ray therapy for tinea capitis is well known. The aim of the study was to specify the epidemiological, clinical and histological characteristics of this disease. In a retrospective study, we collected data from the files of 63 patients, with a history of radiotherapy for tinea capitis, followed between January 1995 and December 2004. Fifty one men and 12 women with a total of 108 BCC of the scalp are reported (1.76 lesion per patient and 1.13 cm on average of diameter). The mean age at the occurrence of the BCC was 45.5 years. Thirty seven percent of BCC occurred on the occipital area; 28.7% were in the parietal site. The most frequent clinical aspect was the nodular BCC (51%) and the cicatricial BCC (35%). Histological study showed a nodular aspect in 74 % and pigmentation in 62% of cases. It is concluded that BCC of the scalp following X-ray therapy for tinea capitis have some clinical and histological particularities. It represents the most frequent tumour developing on irradiated scalp.

[Reasons for the increased incidence of skin cancer]

The cutaneous malignancies with an increasing incidence in Japan are squamous cell carcinoma, basal cell carcinoma, and malignant melanoma. As a precancerous state or early lesion, actinic keratoses also deserve attention. According to a nationwide questionnaire survey (responses from 94 centers), basal cell carcinoma has the highest incidence and accounts for nearly 50% of all skin malignancies, followed by squamous cell carcinoma (31%) and malignant melanoma (21%). The number of cases of each tumor has grown annually, and comparison of the percent increases between 1987 and 2001 shows an increase of about 1.5-fold for basal cell carcinoma or 1.7-fold for squamous cell carcinoma or malignant melanoma. Supported by a Grant-in-Aid for Cancer Research from the Ministry of Health, Labor and Welfare, the Malignant Skin Tumor Research Group has been investigating the factors behind these increases by detailed statistical analysis of data obtained from 1987 onwards from designated centers (19-22 centers). Numerous factors have been suggested by this research, but the most important was concluded to be ultraviolet radiation.

Hair cycle-dependent basal cell carcinoma tumorigenesis in Ptc1neo67/+ mice exposed to radiation

We examined the effects of hair cycle phase on basal cell carcinoma (BCC) tumorigenesis induced by radiation in mice lacking one Patched allele (Ptc1(neo67/+)). Our results show that Ptc1(neo67/+) mouse skin irradiated in early anagen is highly susceptible to tumor induction, as a 3.2-fold incidence of visible BCC-like tumors was observed in anagen-irradiated compared with telogen-irradiated mice. Microscopic nodular BCC-like tumors were also enhanced by irradiation during active hair-follicle growth phases. Interestingly, histologic examination of the tumors revealed a qualitative difference in BCC tumorigenesis depending on hair growth phase at the time of exposure. In fact, in addition to typical BCC-like tumors, we observed development of a distinct basal cell tumor subtype characterized by anti-cytokeratin 14 and anti-smooth muscle actin reactivity. These tumors showed relatively short latency and rapid growth and were strictly dependent on age at irradiation, as they occurred only in mice irradiated in early anagen phase. Examination of anatomic and immunohistochemical relationships revealed a close relation of these tumors with the follicular outer root sheath of anagen skin. In contrast, there are strong indications for the derivation of typical, smooth muscle actin-negative BCC-like tumors from cell progenitors of interfollicular epidermis. These results underscore the role of follicular bulge stem cells and their progeny with high self-renewal capacity in the formation of basal cell tumors and contribute to clarify the relationship between target cell and tumor phenotype in BCC tumorigenesis induced by radiation.

Skin lesions in adult liver transplant recipients: a study of 100 consecutive patients

BACKGROUND

The surgical advances made in the area of organ transplantation along with the use of more efficacious immunosuppression have meant an increase in patient survival. This longer-living transplant population has started to exhibit cutaneous problems, some of which lead to an increased mortality while others lead to a decline in the quality of life.

OBJECTIVES

The primary objective was to determine the different types of cutaneous lesions encountered in the adult liver transplant population. Secondary objectives were to determine the impact, if any, of the duration of transplant, the type of immunosuppression involved and the degree of sun exposure and skin phototype, on the skin cancers encountered in this transplanted population.

METHODS

Two dermatologists examined 100 consecutive liver transplant recipients (LTRs) attending the transplant outpatient department. Skin examination included the face and whole body and lesions found were categorized into the following groups: cutaneous malignancies, squamoproliferative lesions, cutaneous infections and others that did not fall into any of these categories.

RESULTS

The reasons for organ transplantation were numerous. The mean age at transplantation was 42.5 years. The average time since transplantation was 5.5 (range 0.75-16 years). Four patients developed skin cancers; among them there were a total of seven skin cancers (one squamous cell carcinoma, six basal cell carcinomas). Fungal infections accounted for 19% of all cutaneous infections seen, viral infections 2% and bacterial infections 5%. Triple-drug immunosuppressive therapy (ciclosporin A, azathioprine and prednisolone) was used in 35% of LTR patients, while dual therapy (tacrolimus and prednisolone) was used in 48% and monotherapy (tacrolimus) was used in 17% of LTRs.

CONCLUSIONS

Immunosuppressive therapy is believed to be one of the most important risk factors in the development of skin cancer in solid organ transplant recipients. The relatively low prevalence of skin cancer in our liver transplant population may in part be explained by the relatively high percentage of recipients on dual and monotherapy (48% and 17% respectively), and the shorter duration of therapy. Our study suggests that although LTRs are at higher risk of developing nonmelanoma skin cancer than the general population, the risk is comparable with other solid organ transplant recipients.

Risk factors for skin cancers: a nested case–control study within the Nurses’ Health Study

BACKGROUND

Constitutional factors and sun exposure are associated with skin cancer risk. However, these relations are complex and differ according to skin cancer type.

METHODS

We examined the associations of constitutional risk factors and sun exposure with the risks of three types of skin cancer simultaneously and evaluated the interaction between constitutional susceptibility and sun exposure in a nested case-control study within the Nurses' Health Study [200 melanoma, 275 squamous cell carcinoma (SCC), and 283 basal cell carcinoma (BCC) cases, and 804 controls]. Information regarding skin cancer risk factors was obtained from the retrospective supplementary questionnaire.

RESULTS

Constitutional susceptibility was an independent risk factor for all three types of skin cancer. Sunlamp usage or tanning salon attendance was a risk factor for melanoma after adjusting for potential confounding variables (OR for ever vs never usage, 2.06, 95% CI 1.30-3.26). Higher sun exposure while wearing a bathing suit was an independent risk factor for all three types of skin cancer. We observed a significant interaction between constitutional susceptibility and sun exposure while wearing a bathing suit on melanoma risk (P, interaction, 0.03); women with the highest susceptibility and highest exposure had an OR of 8.37 (95% CI 3.07-22.84). This interaction was weaker and non-significant for SCC and BCC.

CONCLUSIONS

These data largely confirm past studies on risk factors for skin cancer but provide evidence of difference on the strength of these risk factors for melanoma compared with SCC and BCC.

Multiple large surface photodynamic therapy sessions with topical methylaminolaevulinate in PTCH heterozygous mice

BACKGROUND

Photodynamic therapy (PDT) combines the administration of a photosensitizer with its subsequent activation by light of the appropriate wavelength. Methylaminolaevulinate (MAL) is a photosensitizer precursor, transformed by cells into protoporphyrin IX. The PTCH gene plays a central role in the genesis of basal cell carcinoma (BCC). The PTCH transgenic mouse develops microscopic BCCs when chronically exposed to ultraviolet (UV) or ionizing radiation.

OBJECTIVES

The aim of this study was to explore the ability of multiple large surface MAL-PDT to prevent BCC, using the PTCH heterozygous mouse as a model.

METHODS

Thirty-five mice were exposed to UV radiation for a total of 20 weeks. Group 1 (20 mice) was exposed only to UV whereas group 2 (15 mice) was exposed to UV and weekly to MAL-PDT. At 28 weeks the mice were killed and the skin of the back processed for standard histopathology. Assessment was blind and any slide showing the presence of BCC was counted as a single BCC. The number of mice in groups 1 and 2 showing BCC were compared using Fisher's exact test.

RESULTS

Nineteen BCCs in nine mice from group 1 were found, but no BCCs in mice from group 2. The difference was statistically significant (P = 0.001).

CONCLUSIONS

Weekly suberythematous PDT sessions with topical MAL were able to delay the development of microscopic BCCs in PTCH mice chronically exposed to UV radiation.

[Exposure to sun radiation as a risk factor for the occurrence of basal cell carcinoma in the Montenegrian population]

BACKGROUND/AIM

[corrected] Basal cell carcinoma (BCC) is the most frequent form of carcinomas in the whites. Among the environmental factors, the most important risk factor for its occurrence is the expasure to sun radiation. The aim of this study was to assess the role of the sun radiation in the development of basal cell carcinoma BCC in the Montenegrian population.

METHODS

A case-control study was conducted in a period from 2002-2003. The study group included 100 histopatologically confirmed cases with BCC, while the control group included 100 patients from the same population, who did not present skin cancer and who were individually matched with the cases from the study group by sex and age (+/- 5 years). All the participants were interviewed using an epidemiological questionnaire. For statistical analysis, the chi-squared test and univariate logistic regression analysis were used.

RESULTS

The risk for development of BCC was increased in the persons: that always had burns with no tan during the exposure to sunlight (OR = 1.75; 95% CI = 1.20-2.55; p = 0.003); that developed sunburns after two hours of the exposure to sunlight (OR = 3.72; 95% CI = 2.39-5.79; p < 0.001) that kept light tan or remained without changes in childhood and adolescence after the repeated exposures to sunlight (OR = 2.92; 95% CI = 1.89-4.52; p < 0.001) that often had severe and painful sunburns (OR = 4.48; 95% CI = 2.74-7.33; p < 0.001).

CONCLUSION

Our study confirmed the significance of sunlight exposure for the development of BCC.

4-Nitroquinoline-1-oxide-induced mutagen sensitivity and risk of nonmelanoma skin cancer: a case-control analysis

The UV radiation-mimetic chemical 4-nitroquinoline-1-oxide (4-NQO) is thought to induce squamous cell carcinoma (SCC) similar to those induced by UV radiation in animals. Therefore, we tested the hypothesis that cellular sensitivity to 4-NQO is associated with risk of developing skin cancer in a case-control study of 191 patients with nonmelanoma skin cancer (NMSC; 81 SCC and 110 basal cell carcinoma (BCC)) and 176 cancer-free controls. Short-term blood cultures were treated with 4-NQO at a final concentration of 10 microM for 24 hours and scored for chromatid breaks in 50 well-spread metaphases. We found that the mean frequency of chromatid breaks per cell (b/c) was significantly higher in the cases (mean+/-SD, 0.46+/-0.43 for SCC and 0.43+/-0.38 for BCC) than in the controls (0.25+/-0.25; P<0.001 for both comparisons) and were associated with more-than-twofold increased risk for both SCC and BCC after adjustment for known risk factors. Therefore, our findings support the notion that sensitivity to 4-NQO reflects susceptibility to UV-induced NMSC. However, there is a lack of correlation between UVB-induced b/c and 4-NQO-induced b/c in this study population. Therefore, these findings need to be verified by additional studies.

Seborrhoeic keratosis and malignancy: collision tumour or malignant transformation?

A retrospective study of 813 histological specimens reported as seborrhoeic keratoses included 43 (5.3%) associated with non-melanoma skin cancer. Intraepidermal carcinoma (squamous cell carcinoma in situ) was the most common of these (36). There were five basal cell carcinomas (one with intraepidermal carcinoma also) and two invasive squamous cell carcinomas. No melanomas were reported. Twenty-seven of the intraepidermal carcinomas appeared to arise within the seborrhoeic keratosis as did one of the invasive squamous cell carcinomas. Of these 28 lesions, the head was the most common site. Fourteen were clinically diagnosed as a non-melanoma skin cancer with only nine clinically felt to be a seborrhoeic keratosis. These lesions may represent malignant transformation within the seborrhoeic keratosis. Twelve specimens reported adjacent dual pathologies, with the trunk and limbs the most common sites. Seven were diagnosed clinically as a skin malignancy, whereas three were thought to be solar keratoses. Clinically, the remaining two were seborrhoeic keratoses. The origin of the malignancy in these cases is less obvious and may represent collision tumours. Three curette specimens could not be assessed for architecture.

Seborrhoeic keratoses with associated lesions: a retrospective analysis of 85 lesions

Seborrhoeic keratoses are benign epidermal neoplasms that are rarely associated with other skin lesions especially malignancies. In this study, the aim was to assess the incidence of associated lesions occurring either adjacent to or contiguous with a seborrhoeic keratosis. A retrospective case series over a 12-month period was carried out. In total, 639 consecutive histologically diagnosed seborrhoeic keratoses were identified, of which 85 (9%) were found to be associated with other lesions. Of these associated lesions, 44 (7%) were malignant, with four of these found to be arising within the seborrhoeic keratosis. These associated lesions included premalignant lesions, malignancies, melanocytic lesions and miscellaneous lesions. Men (59%) were affected more commonly than women. The average age was 74 years (range 33-98 years). Seborrhoeic keratoses associated with other lesions were found most commonly on the head and neck. The incidence of associated lesions, in particular malignancy arising within seborrhoeic keratoses may be higher than previously thought. This may be an incidental phenomenon, or seborrhoeic keratosis could represent a precursor lesion. Therefore, seborrhoeic keratoses that have undergone recent clinical change should be considered for biopsy and histological examination.

Immune protection, natural products, and skin cancer: is there anything new under the sun?

Non-melanoma skin cancers such as squamous cell carcinoma and basal cell carcinoma are the most common types of human neoplasms, representing one third of all new malignancies diagnosed in the US. The number of new cases diagnosed per year in the US alone is approaching one million and continues to rise. Ultraviolet (UV) radiation from the sun is a major cause of non-melanoma skin cancer in humans. Aside from the mutagenic effects of UV radiation, there are suggestions from clinical studies and evidence in animal models that the immune system plays an important role in preventing skin cancer development and progression, and is suppressed by cutaneous exposure to UV radiation. In this article, we review the research on new and existing agents that are being developed to protect the skin immune response from suppression by UV radiation. We also discuss the current state of knowledge regarding their mechanism of action in humans as well as animal models of photosuppression, and their efficacy in cancer prevention.

Cyclooxygenase-2 overexpression in human basal cell carcinoma cell line increases antiapoptosis, angiogenesis, and tumorigenesis

Cyclooxygenase-2 (COX-2) is critical for tumor formation, angiogenesis, metastasis, and prognosis. In this study, the role of COX-2 in antiapoptosis, tumorigenesis, and angiogenesis of human basal cell carcinoma (BCC) cells was investigated. Transfection of COX-2 constitutive expression vector into a BCC cell line yielded several overexpressing clones. All transfectants demonstrated remarkable resistance to ultraviolet B-induced apoptosis (confirmed by flow cytometry analysis, morphological change, and DNA fragmentation). Immunoblot analysis revealed marked increases in apoptosis-regulated genes Mcl-1 and Bcl-2. A 10-fold concentrated conditioned medium from COX-2-overexpressing BCC cells exhibited higher angiogenic activity in Matrigel plug and human umbilical vein endothelial cell tube formation assay. Cells exhibited increased levels of vascular endothelial growth factor-A (VEGF-A) mRNA and protein, and secreted VEGF-A and basic fibroblast growth factor (bFGF). COX-2-specific small interfering RNA markedly reduced the secreted species. After 7 weeks of inoculation, the tumor volume of COX-2-overexpressing cells in severe combined immunodeficient mice was significantly greater than that of vector control cells. Immunohistochemical analysis of CD31-positive vessels revealed a two-fold increase in microvessel density in COX-2 tumors, compared to control vector tumors. Our data indicate that Mcl-1 and Bcl-2, as well as VEGF-A and bFGF, are downstream effectors of COX-2-induced antiapoptosis and angiogenesis, respectively.

Infliximab for severe, treatment-resistant psoriasis: a prospective, open-label study

BACKGROUND

Infliximab, a mouse-human chimeric monoclonal antibody directed against tumour necrosis factor-alpha, has been shown to be effective for moderate to severe psoriasis, but there are few data published on its use in recalcitrant, treatment-resistant disease or in combination with other antipsoriatic therapies.

OBJECTIVES

To report our experience with infliximab in the treatment of patients attending a tertiary referral service with severe recalcitrant disease.

METHODS

All patients attending a tertiary referral service for severe psoriasis who were treated with infliximab between 2002 and July 2005 were entered into a prospective, open-label study. Details on disease phenotype, clinical course and adverse events were recorded together with measures of disease severity [Psoriasis Area and Severity Index (PASI), Dermatology Life Quality Index, clinical photography] at baseline, weeks 2 and 6, and then at 2-monthly intervals throughout the treatment period.

RESULTS

Twenty-three patients were treated with infliximab during the study; one patient had pustular psoriasis and was therefore excluded from statistical analysis. All had severe disease (baseline PASI 26.5+/-6.7, mean+/-SD, n=22) and had received at least two systemic therapies for psoriasis in the past; 16 were taking one or more concomitant therapies at the time of treatment initiation. At week 10, 95% had achieved a 50% or greater improvement in baseline PASI (PASI 50), and 77% had achieved a 75% or greater improvement (PASI 75). Efficacy was sustained in the longer term, with eight of 10 patients on treatment for more than 11 months maintaining at least a PASI 50. Only one patient had treatment withdrawn due to lack of efficacy, two suffered severe systemic infections including extrapulmonary tuberculosis (splenic abscess) and cellulitis, and six have discontinued due to adverse effects including infusion reactions (two), severe thrombocytopenia (one), hepatitis (one) and malignancy (two).

CONCLUSIONS

Data from this open-label study suggest that infliximab is a rapidly effective treatment for patients with severe, treatment-resistant disease, although approximately 25% of patients had to discontinue therapy due to the development of serious adverse effects. Long-term follow-up, continued pharmacovigilance, and further controlled comparative studies will be required to evaluate fully the risks associated with infliximab in the context of this already difficult to treat population.

One-fifth of basal cell carcinomas have a morphoeic or partly morphoeic histology: Implications for treatment

A retrospective analysis of the histopathology reports for all first or single basal cell carcinomas (1567) surgically treated over a 13-year period, was undertaken. Basal cell carcinomas classified by standard skin pathology nomenclature were divided into three groups: purely morphoeic basal cell carcinomas, partly morphoeic basal cell carcinomas and non-morphoeic basal cell carcinomas. A morphoeic or partly morphoeic histology was reported in 21.8% of basal cell carcinomas, particularly on the head and neck and in those over the age of 64 years. This percentage may increase further as patients live longer, and has important implications for treatment selection.

Controversies in the public health approach to keratinocyte carcinomas

Keratinocyte carcinomas are very common cancers in fair-skinned populations throughout the world. The term 'keratinocyte carcinoma' includes basal and squamous cell carcinoma of the skin, but not other cancers that may be included under the more ambiguous term 'nonmelanoma skin cancer'. Incidence and mortality are important for assessing impact and recent research suggests that these cancers are increasing in incidence in young adults. There is evidence to suggest that this trend may be due, in part, to the popularity of ultraviolet exposures in commercial tanning facilities. Mortality from keratinocyte carcinoma reveals distinct patterns suggestive of an important role of human papilloma virus infection. Ultimately, our aim is to reduce mortality and morbidity from these cancers, and to that end several large-scale trials of public health interventions have been conducted that may help point the way forward.

Genetics and risk factors for basal cell carcinoma

Nonmelanoma skin cancer (NMSC) is the commonest cancer in whites and its incidence is increasing worldwide. The prevalence of this cancer is predicted to equal that of all others combined and it was estimated that there were over 2 million cases diagnosed in the U.S.A. in 2004. Patients exhibit marked differences in clinical phenotype with variations in tumour numbers, rate of tumour accrual, site and histological subtype. Furthermore, patients are at increased risk of other cutaneous and noncutaneous cancers. The factors accounting for this variation are complex and still not completely understood. Clearly, ultraviolet light (UV) exposure is a major influence but its relationship to clinical phenotype is not yet clear. In addition, immunosuppression is a significant risk factor. Our group has identified high-risk groups for the development of further basal cell carcinoma (BCC), namely patients with truncal BCC and those presenting with tumour clusters. This presentation will concentrate on these clinical subgroups as well as immunosuppressed patients. These groups represent significant management challenges and are areas where novel, nonsurgical treatment options may make a significant clinical impact in patient care. The risk factors predisposing to these clinical phenotypes will be discussed, including genetic factors and UV exposure. Potential clinical applications, including predictive indices, will be considered.

Comparison of risk patterns in carcinoma and melanoma of the skin in men: a multi-centre case-case-control study

We directly compared risk factors between 214 histologically confirmed melanomas (CMM), 215 basal-cell carcinomas (BCC) and 139 squamous-cell carcinomas (SCC) in a multiple case–case–control study with 349 controls from patients without dermatological disease admitted to the same hospitals. Subjects with fair hair had a significant risk increase for all types of tumours at a comparable level (OR_adj for blonde hair: CMM 2.3; SCC 2.4; BCC 2.3). The effect of pale eyes was significant and similar for CMM and BCC (OR_adj 2.6). Intermittent sun exposure measured in hours spent at beach during holidays was significant for both CMM (OR_adj 2.6 for more than 7000 lifelong hours) and BCC (OR_adj 2.1 for more than 7000 lifelong hours), while SCC exhibited a significant risk increase for chronic exposure to sunlight measured in hours of outdoor work (OR_adj 2.2 for more than 6000 lifelong hours). In the case–case comparison using a multinomial logistic regression model, we found a statistically significant risk difference for pale eyes, and number of naevi in the CMM group, compared to other skin cancers. For intermittent sun exposure, there was a significant risk difference of BCC when compared to the risk of SCC. Factors influencing risk of SCC are different, with chronic exposure to sun playing a major role in causing this type of carcinoma.

Role of apoptosis stimulus factor and its ligand in the induction of apoptosis in some ultraviolet induced diseases

BACKGROUND

Fas (factor of apoptosis stimulus) is one of the death receptors belonging to the tumor necrosis factor superfamily of receptors. When bound to its ligand, Fas-ligand (Fas-L), it triggers apoptosis. Ultraviolet (UV) rays can induce keratinocyte apoptosis by Fas/Fas-L interaction.

AIM

The aim of the study was to evaluate the role of Fas and Fas-L in basal cell carcinoma (BCC) as an example of malignant neoplasm and discoid lupus erythematosus (DLE) as a benign skin disease, which are both induced by UV.

SUBJECTS AND METHODS

The study included 20 cases of BCC, 20 cases of DLE and ten control cases. All biopsies of BCC and DLE were examined histopathologically. They were also examined for Fas and Fas-L by PCR.

RESULTS

In BCC, apoptosis was detected in 60 percent of cases. Fas was found to be positive in only one case and it was found to be negative in the other 19 cases (95 %). Fas-L was found to be positive in 100 percent of cases. In DLE, apoptosis was detected in 90 percent of cases. Fas was positive in 80 percent of cases, Fas-L was positive in 90% of cases.

CONCLUSION

Over-expression of Fas-L and lack of expression of Fas by tumor cells together with other factors act in favor of BCC by helping its survival and progression. Also, it seems that Fas/Fas-L interaction plays a critical role in the apoptosis seen in cases of DLE and hence in the pathogenesis of DLE.