Radiation dose as a risk factor for malignant melanoma following childhood cancer

Malignant melanoma in a 12-year-old boy 17 months after completing hepatoblastoma treatment

BACKGROUND

Melanoma is rare as a secondary malignant neoplasm among childhood cancer survivors.

CASE

We report a case of a 12-year-old boy who developed malignant melanoma with systemic metastases 17 months after completing treatment for hepatoblastoma. The diagnosis was made unexpectedly based on a bone marrow examination. The patient did not respond to immune checkpoint inhibitor therapy and died 6 weeks after being diagnosed with melanoma. Whole-exome sequencing to examine 103 genes associated with cancer predisposition did not identify any germ-line variants.

CONCLUSION

This case study provides a unique example of melanoma in a childhood cancer survivor following hepatoblastoma treatment but does not identify any candidate variant to link hepatoblastoma and melanoma.

Equivalent doses for anticancer agents used in pediatric oncology: A literature review and evaluation of a novel approach for conversion factors

BACKGROUND

Epidemiological research on late effects of therapy shows the necessity to aggregate chemotherapy agents to substance classes. This requires using conversion factors by substance classes.

AIMS

The aim of this study was to identify previously used conversion factors from the literature, to present a novel approach for additional factors, and to compare these approaches.

METHODS AND RESULTS

A literature review was performed, which identified two main principles of deriving conversion factors: effect-equivalence and equimolar. Thirty-five articles presenting effect equivalence-based factors in the widest sense were found in the literature. Ten articles presented the equimolar approach which can be applied to almost all chemotherapy substances. Based on a comprehensive list of treatment protocols used in German pediatric oncology, we derived alternative conversion factors from typical doses. We compared the conversion factors using Pearson correlation coefficients and linear regression. At least two types of conversion factor were available for each of the 49 substances included. The equivalent effect-based and the typical dose-based factors were highly correlated with a regression coefficient close to 1. The equimolar factors are independent.

CONCLUSIONS

For substances for which no conversion factor based on some type of effect equivalence has been published so far, a factor based on a typical doses-approach may be used in epidemiological late effects research. Doses aggregated based on the equimolar approach may not be compatible with doses aggregated based on equivalent effects.

Long-Term Risk of Skin Cancer Among Childhood Cancer Survivors: A DCOG-LATER Cohort Study

BACKGROUND

Skin cancer is common after radiotherapy among childhood cancer survivors (CCSs). We studied risks and risk factors for subsequent skin cancers, with emphasis on radiation dose, exposed skin surface area, and chemotherapeutic agents.

METHODS

The DCOG-LATER cohort study includes 5-year Dutch CCSs diagnosed 1963-2001. Subsequent skin cancers were identified from record linkages with the Netherlands Cancer Registry and Dutch Pathology Registry. Incidence rates were compared with general population rates. Multivariable Cox regression models were used, applying a novel method of case-control sampling enabling use of tumor location in cohort analyses. All statistical tests were two-sided.

RESULTS

Among 5843 CCSs, 259 developed 1061 basal cell carcinomas (BCCs) (standardized incidence ratio [SIR] = 29.8, 95% confidence interval [CI] = 26.3 to 33.6; excess absolute risk per 10 000 person-years (EAR) = 24.6), 20 had melanoma (SIR = 2.3, 95% CI = 1.4 to 3.5; EAR = 1.1), and 10 had squamous cell carcinoma (SIR = 7.5, 95% CI = 3.6 to 13.8; EAR = 0.8). Cumulative incidence of BCC 40 years after childhood cancer was 19.1% (95% CI = 16.6 to 21.8%) after radiotherapy vs 0.6% expected based on general population rates. After a first BCC, 46.7% had more BCCs later. BCC risk was associated with any radiotherapy to the skin compartment of interest (hazard ratio [HR] = 14.32, 95% CI = 10.10 to 20.29) and with estimated percentage in-field skin surface area (26-75%: HR = 1.99, 95% CI = 1.24 to 3.20; 76-100%: HR = 2.16, 95% CI = 1.33 to 3.53, vs 1-25% exposed; Ptrend among exposed = .002), but not with prescribed radiation dose and likelihood of sun-exposed skin-area. Of all chemotherapy groups examined, only vinca alkaloids increased BCC risk (HR = 1.54, 95% CI = 1.04 to 2.27).

CONCLUSION

CCSs have a strongly, 30-fold increased BCC risk. BCC risk appears to increase with increasing skin surface area exposed. This knowledge underscores the need for awareness by survivors and their health care providers.

Second malignant neoplasm following childhood cancer: A nested case-control study of a recent cohort (1987-2004) from the Childhood Cancer Registry of the Rhône-Alpes region in France

From a population-based cohort of cases of first cancers diagnosed between 1987 and 2004, before the patient's age of 15 years, the authors conducted a nested case-control study, matching 64 patients who experienced a second malignant neoplasm (SMN) with 190 controls. SMNs comprised 10 leukemia or myelodysplastic syndromes, 5 lymphomas induced by Epstein-Barr virus after allograft, and 49 solid tumors, including mainly 25 carcinomas (17 of the thyroid), 9 bone sarcomas, and 7 central nervous system (CNS) tumors. The median latency occurrence was 6.5 years, and that of thyroid carcinomas induced by 12 Gy fractioned total body irradiation (TBI) was 7.6 years. The relative risk (RR) of an SMN was increased by genetic and family factors and increased 17 to 69 times according to the dose of radiotherapy administered in the region for the first cancer. Age younger than 4 years at the time of radiotherapy increased the risk of SMN. Chemotherapy adjusted according to the dose of radiotherapy administered in the field yielded a greater RR of an SMN only for cumulative doses exceeding 2 g/m² of epipodophyllotoxin but not for alkylating agents or platinum compounds. The RR of secondary leukemia increased 10-fold following high doses of epipodophyllotoxin >2 g/m² but was not affected by alkylating agents or anthracyclines. The crude RR of a solid SMN developing after radiotherapy was very high at 18 and reached 90.7 for thyroid carcinoma after TBI, whereas the authors observed no increased risk associated with chemotherapy. These results confirm the risk of secondary leukemia after epipodophyllotoxin and of solid tumor after radiotherapy.

Surgical Management of Melanoma

The surgical management of melanoma has undergone considerable changes over the past several decades, as new strategies and treatments have become available. Surgeons play a pivotal role in all aspects of melanoma care: diagnostic, curative, and palliative. There is a high potential for cure in patients with early-stage melanoma and the selection of an appropriate operation is very important for this reason. Staging the nodal basin has become widespread since the adoption of sentinel lymph node biopsy (SLNB) for the management of melanoma. This operation provides the best prognostic information that is currently available for patients with melanoma. The surgeon plays a central role in the palliation of symptoms resulting from nodal disease and metastases, as melanoma has a propensity to spread to almost any site in the body.

Development of Malignant Melanoma of the Orbit in Previous Radiation Field

We present a case of a 40-year-old woman with a history of retinoblastoma in the left eye treated with enucleation and radiation therapy as an infant who recently developed worsening pain and exophthalmos in her right eye. Multimodality imaging demonstrated an enhancing, FDG-avid mass in the medial right orbit with associated bone destruction and extension into the ethmoid sinus. Pathologic analysis after excision showed a highly undifferentiated tumor consistent with melanoma. Although development of malignant melanoma in an irradiated field is rare, it should be considered in the differential, especially in childhood cancer survivors at increased risk of second malignant neoplasms.

Survivorship

Significant therapeutic advances for soft tissue sarcomas allow increasing numbers of patients--adult and pediatric--to achieve long term survival. However, the harsh cytotoxic therapies are responsible for adverse physical and psychosocial effects that require long-term follow-up care, specific to survivorship issues. In the adult and pediatric patient population, guidelines for care developed by experts in comprehensive survivorship clinics are evolving to assist the practitioner while on-line supports bring information directly to the survivors.

Genetic variation as a modifier of association between therapeutic exposure and subsequent malignant neoplasms in cancer survivors

Subsequent malignant neoplasms (SMNs) are associated with significant morbidity and are a major cause of premature mortality among cancer survivors. Several large studies have demonstrated a strong association between the radiation and/or chemotherapy used to treat primary cancer and the risk of developing SMNs. However, for any given therapeutic exposure, the risk of developing an SMN varies between individuals. Genomic variation can potentially modify the association between therapeutic exposures and SMN risk and may explain the observed interindividual variability. In this review, the author provides a brief overview of the current knowledge regarding the role of genomic variation in the development of therapy-related SMNs and discusses the methodological challenges in undertaking an endeavor to develop a deeper understanding of the molecular underpinnings of therapy-related SMNs, such as an appropriate study design, the identification of an adequately sized study population together with a reliable plan for collecting and maintaining high-quality DNA, clinical validation of the phenotype, and the selection of an appropriate approach or platform for genotyping. Understanding the factors that can modify the risk of treatment-related SMNs is critical to developing targeted intervention strategies and optimizing risk-based health care for cancer survivors.

Methodological extensions of meta-analysis with excess relative risk estimates: application to risk of second malignant neoplasms among childhood cancer survivors treated with radiotherapy

Although radiotherapy is recognized as an established risk factor for second malignant neoplasms (SMNs), the dose response of SMNs following radiotherapy has not been well characterized. In our previous meta-analysis of the risks of SMNs occurring among children who have received radiotherapy, the small number of eligible studies precluded a detailed evaluation. Therefore, to increase the number of eligible studies, we developed a method of calculating excess relative risk (ERR) per Gy estimates from studies for which the relative risk estimates for several dose categories were available. Comparing the calculated ERR with that described in several original papers validated the proposed method. This enabled us to increase the number of studies, which we used to conduct a meta-analysis. The overall ERR per Gy estimate of radiotherapy over 26 relevant studies was 0.60 (95%CI: 0.30-1.20), which is smaller than the corresponding estimate for atomic bomb survivors exposed to radiation as young children (1.7; 95% CI: 1.1-2.5). A significant decrease in ERR per Gy with increase in age at exposure (0.85 times per annual increase) was observed in the meta-regression. Heterogeneity was suggested by Cochran's Q statistic (P < 0.001), which may be partly accounted for by age at exposure.

Second cancers and late mortality in Australian children treated by allogeneic HSCT for haematological malignancy

We examined risk of second cancer and late mortality in a population-based Australian cohort of 717 pediatric allogeneic stem cell transplant (HSCT) recipients treated for a malignant disease during 1982-2007. Record linkage with population-based death and cancer registries identified 17 second cancers at a median of 7.9 years post HSCT; thyroid cancer being the most common malignancy (n=8). The cumulative incidence of second cancer was 8.7% at follow-up, and second cancers occurred 20 times more often than in the general population (standardised incidence ratio 20.3, 95% confidence interval (CI)=12.6-32.7). Transplantation using radiation-based conditioning regimens was associated with increased second cancer risk. A total of 367 patients survived for at least 2 years post HSCT and of these 44 (12%) died at a median of 3.1 years after HSCT. Relapse was the most common cause of late mortality (n=32). The cumulative incidence of late mortality was 14.7%. The observed rate of late mortality was 36 times greater than in the matched general population (standardised mortality ratio 35.9, 95% CI=26.7-48.3). Recipients who relapsed or who had radiation-based conditioning regimens were at higher risk of late mortality. Second cancers and late mortality continue to be a risk for pediatric patients undergoing HSCT, and these results highlight the need for effective screening and survivorship programs.

A large de novo 9p21.3 deletion in a girl affected by astrocytoma and multiple melanoma

Background

Association of melanoma, neural system tumors and germ line mutations at the 9p21 region in the CDKN2A, CDKN2B and CDKN2BAS genes has been reported in a small number of families worldwide and described as a discrete syndrome in melanoma families registered as a rare disease, the melanoma–astrocytoma syndrome.

Case presentation

We here studied two young patients developing melanoma after radiotherapy for astrocytoma, both reporting lack of family history for melanoma or neural system tumors at genetic counselling. Patient A is a girl treated for anaplastic astrocytoma at 10 years and for multiple melanomas on the scalp associated to dysplastic nevi two years later. Her monozygotic twin sister carried dysplastic nevi and a slow growing, untreated cerebral lesion. Direct sequencing analysis showed no alterations in melanoma susceptibility genes including CDKN2A, CDK4, MC1R and MITF or in TP53. By microsatellite analysis, multiplex ligation-dependent probe amplification, and array comparative genomic hybridization a deletion including the CDKN2A, CDKN2B and CDKN2BAS gene cluster was detected in both twin sisters, encompassing a large region at 9p21.3 and occurring de novo after the loss of one paternal allele.

Patient B is a boy of 7 years when treated for astrocytoma then developing melanoma associated to congenital nevi on the head 10 years later: sequencing and multiplex ligation-dependent probe amplification revealed a normal profile of the CDKN2A/CDKN2B/CDKN2BAS region. Array comparative genomic hybridization confirmed the absence of deletions at 9p21.3 and failed to reveal known pathogenic copy number variations.

Conclusions

By comparison with the other germ line deletions at the CDKN2A, CDKN2B and CDKN2BAS gene cluster reported in melanoma susceptible families, the deletion detected in the two sisters is peculiar for its de novo origin and for its extension, as it represents the largest constitutive deletion at 9p21.3 region identified so far.

In addition, the two studied cases add to other evidence indicating association of melanoma with exposure to ionizing radiation and with second neoplasm after childhood cancer. Melanoma should be considered in the monitoring of pigmented lesions in young cancer patients.

Design and validation of a questionnaire for measuring perceived risk of skin cancer

INTRODUCTION

A perceived risk of cancer encourages preventive behavior while the lack of such a perception is a barrier to risk reduction. There are no instruments in Spanish to measure this perceived risk and thus quantify response to interventions for preventing this disease at a population level. The aim of this study was to design and validate a self-administered questionnaire for measuring the perceived risk of skin cancer.

MATERIAL AND METHODS

A self-administered questionnaire with a visual Likert-type scale was designed based on the results of the analysis of the content of a survey performed in 100 patients in the Dr. Ladislao de la Pascua Skin Clinic, Distrito Federal México, Mexico. Subsequently, the questionnaire was administered to a sample of 359 adult patients who attended the clinic for the first time. As no gold standard exists for measuring the perceived risk of skin cancer, the construct was validated through factor analysis.

RESULTS

The final questionnaire had 18 items. The internal consistency measured with Cronbach α was 0.824 overall. In the factor analysis, 4 factors (denoted as affective, behavioral, severity, and susceptibility) and an indicator of risk accounted for 65.133% of the variance.

CONCLUSIONS

The psychometric properties of the scale were appropriate for measuring the perception of risk in adult patients (aged 18 years or more) who attended the dermatology clinic.

Melanoma as a subsequent neoplasm in adult survivors of childhood cancer: a report from the childhood cancer survivor study

BACKGROUND

Childhood cancer survivors have a sixfold increased risk of developing subsequent neoplasms when compared to the general population. We sought to describe the occurrence of melanoma as a subsequent neoplasm among adult survivors of childhood cancer.

PATIENTS AND METHODS

Among 14,358 5-year survivors of childhood cancer diagnosed between 1970 and 1986, we calculated the cumulative incidence, standardized incidence ratio (SIR), and absolute excess risk (AER) of subsequent melanoma. Potential risk factors were assessed using a cause-specific hazards model.

RESULTS

Fifty-seven melanomas (46 invasive, 2 ocular, and 9 in situ) occurred in 51 survivors. The median time to the development of melanoma was 21.0 years (range: 5.6-35.4 years) and the median age at melanoma was 32.3 years (range: 10.9-49.0 years). Initial cancer diagnoses included soft tissue and bone sarcoma (n = 15), leukemia (13), lymphoma (14), central nervous system malignancy (5), Wilms tumor (3), and neuroblastoma (1). The cumulative incidence of first subsequent melanoma at 35 years from initial cancer diagnosis was 0.55% [95% confidence interval (CI): 0.37-0.73]. The SIR of subsequent invasive malignant melanoma of the skin was 2.42 (95% CI: 1.77-3.23), and the AER was 0.10 (95% CI: 0.05-0.15) per 1,000 person-years. No statistically significant associations were found between melanoma risk and family history of cancer, demographic, or treatment-related factors.

CONCLUSION

Survivors of childhood cancer have an approximate 2.5-fold increased risk of melanoma. Early screening and prevention strategies are warranted.

Radiotherapy as a risk factor for malignant melanoma after childhood skin hemangioma

The aim of this study was to determine therapy-related risk factors for the development of melanoma after hemangioma. A cohort study was conducted among 4620 patients treated before 16 years of age for skin hemangioma in France. A nested case-control study was also conducted on 13 patients who developed a melanoma (cases) matched with five controls in cohort according to sex, age at the hemangioma diagnostic, the calendar year of occurrence of the hemangioma, and follow-up. The radiation dose received at the site of the melanoma and at the same site in controls was estimated, and named 'local dose'. A total of 13 melanomas were registered during an average follow-up of overall 35 years, the risk of developing melanoma after a hemangioma treatment was 2.5-fold higher [95% confidence interval (CI): 1.4-4.1] compared with that of the general population, this ratio being only 0.8 (95% CI: 0.05-3.6) in 896 patients who did not receive radiotherapy, but 3.0 (95% CI: 1.6-5.1) after radiotherapy. When adjusting on sex, age, and year of the treatment and follow-up duration, melanoma risk was 11.9 (95% CI: 1.4-123) times higher in patients treated with ytrium 90 than in the ones who did not received radiotherapy. In the case-control study, the risk of melanoma was not linked to the local radiation dose. Indeed, the increase in melanoma risk was observed even for very low local doses. Compared with the corresponding skin areas in patients who did not receive radiotherapy, the ones having received less than 0.001 Gy had a melanoma risk of 3.9 (95% CI: 0.5-32) and those who received more than 0.01 Gy had a risk of 6.9 (0.5-99). This study suggests that radiation therapy of skin hemangioma increases the risk of further melanoma, but we were not able to evidence a relation with the local dose. Nevertheless, childhood treated for hemangioma should be considered at risk for developing melanoma and suspicious pigmented lesions should be carefully evaluated even far from treated areas.

Malignant melanoma as second malignant neoplasm in long-term childhood cancer survivors: a systematic review

This systematic review provides information on malignant melanoma as second malignant neoplasm (SMN) after childhood cancer and evaluates its risk factors. Study reports describing incidences of SMN and malignant melanoma as SMN in a population of childhood cancer survivors (CCS) were included. Of 151,575 CCS, 4,010 (2.6%) children developed an SMN, 212 of which were melanoma (5.3% or 0.14% of all CCS). The following risk factors for malignant melanoma as SMN were identified: radiotherapy, or the combination alkylating agents and anti-mitotic drugs. Melanomas are most frequently observed after Hodgkin disease, hereditary retinoblastoma, soft tissue sarcoma, and gonadal tumors.

Meta-analysis of second cancer risk after radiotherapy among childhood cancer survivors

Cancer risks among childhood cancer survivors following radiotherapy have not yet been well characterised in terms of radiation dose. A meta-analysis of studies on the excess relative risk per gray (ERR) of second cancer was conducted previously; unfortunately, the small number of eligible studies restricted quantitative evaluations. To solve this problem, a statistical method to calculate ERR estimates from other estimates was developed, and a meta-analysis was conducted again. The PubMed database was searched and 26 relevant studies were identified. ERR estimates were available in 15 studies, and for the other 11 studies, the regression-based model was used to calculate ERR estimates from other estimates. The overall ERR estimate was 0.40, which was much lower than that of atomic bomb survivors exposed as young children. Heterogeneity of the risk among studies was suggested, and a further study is needed to explore the heterogeneity among studies.

Two patients with Hailey-Hailey disease, multiple primary melanomas, and other cancers

BACKGROUND

Hailey-Hailey Disease (HHD) is an autosomal dominant skin disorder that is characterized by erythematous and sometimes vesicular, weeping plaques of intertriginous regions. Squamous cell carcinoma and basal cell carcinoma arising in lesions of HHD have been described in the literature. To our knowledge, there are no reports of melanoma or noncutaneous malignant neoplasms associated with HHD.

OBSERVATIONS

We discuss the mechanisms of oncogenicity, including genetic, environmental, and iatrogenic factors, in 2 patients with HHD, multiple primary melanomas, and other cancers. Patient 1 had a mucoepidermoid carcinoma of the parotid gland. Patient 2 had a history of acute monoblastic leukemia and malignant peripheral nerve sheath tumor as well as radiologic evidence of an acoustic neurilemmoma.

CONCLUSIONS

The cause of the cancers in these 2 patients is likely multifactorial. We describe the patients to draw attention to the possible association between HHD and cancer. Additional research should be performed to determine whether patients with HHD have an increased incidence of cancer.

Relationship between radiation exposure and risk of second primary cancers among atomic bomb survivors

Radiation exposure is related to risk of numerous types of cancer, but relatively little is known about its effect on risk of multiple primary cancers. Using follow-up data through 2002 from 77,752 Japanese atomic bomb survivors, we identified 14,048 participants diagnosed with a first primary cancer, of whom 1,088 were diagnosed with a second primary cancer. Relationships between radiation exposure and risks of first and second primary cancers were quantified using Poisson regression. There was a similar linear dose-response relationship between radiation exposure and risks of both first and second primary solid tumors [excess relative risk (ERR)/Gy = 0.65; 95% confidence interval (CI), 0.57-0.74 and ERR/Gy = 0.56; 95% CI, 0.33-0.80, respectively] and risk of both first and second primary leukemias (ERR/Gy = 2.65; 95% CI, 1.78-3.78 and ERR/Gy = 3.65; 95% CI, 0.96-10.70, respectively). Background incidence rates were higher for second solid cancers, compared with first solid cancers, until about age 70 years for men and 80 years for women (P < 0.0001), but radiation-related ERRs did not differ between first and second primary solid cancers (P = 0.70). Radiation dose was most strongly related to risk of solid tumors that are radiation-sensitive including second primary lung, colon, female breast, thyroid, and bladder cancers. Radiation exposure confers equally high relative risks of second primary cancers as first primary cancers. Radiation is a potent carcinogen and those with substantial exposures who are diagnosed with a first primary cancer should be carefully screened for second primary cancers, particularly for cancers that are radiation-sensitive.

Can we reduce the incidence of second primary malignancies occurring after radiotherapy? A critical review

Second primary malignancies (SPMs) occurring after oncological treatment have become a major concern during the past decade. Their incidence has long been underestimated because most patients had a short life expectancy after treatment or their follow-up was shorter than 15 years. With major improvement of long-term survival, longer follow-up, cancer registries and end-result programs, it was found that the cumulative incidence of SPM could be as high as 20% of patients treated by radiotherapy. This cumulative proportion varies with several factors, which ought to be studied more accurately. The delay between irradiation and solid tumor emergence is seldom shorter than 10 years and can be as long as half a century. Thus, inclusion in a cohort of patients with a short follow-up leads to an underestimation of the proportion of SPM caused by treatment, unless actuarial cumulative incidence is computed. The incidence varies with the tissue and organs, the age of the patient at treatment, hereditary factors, but also, and probably mainly, with dose distribution, size of the irradiated volume, dose, and dose-rate. An effort toward a reduction in their incidence is mandatory. Preliminary data suggest that SPMs are mainly observed in tissues having absorbed doses above 2 Gy (fractionated irradiation) and that their incidence increases with the dose. However, in children thyroid and breast cancers are observed following doses as low as 100 mGy, and in adults lung cancers have been reported for doses of 500 mGy, possibly due to interaction with tobacco. The dose distribution and the dose per fraction have a major impact. However, the preliminary data regarding these factors need confirmation. Dose-rates appear to be another important factor. Some data suggest that certain patients, who could be identified, have a high susceptibility to radiocancer induction. Efforts should be made to base SPM reduction on solid data and not on speculation or models built on debatable hypotheses regarding the dose-carcinogenic effect relationship. In parallel, radiation therapy philosophy must evolve, and the aim of treatment should be to deliver the minimal effective radiation therapy rather than the maximal tolerable dose.

A review of dosimetry studies on external-beam radiation treatment with respect to second cancer induction

It has been long known that patients treated with ionizing radiation carry a risk of developing a second cancer in their lifetimes. Factors contributing to the recently renewed concern about the second cancer include improved cancer survival rate, younger patient population as well as emerging treatment modalities such as intensity-modulated radiation treatment (IMRT) and proton therapy that can potentially elevate secondary exposures to healthy tissues distant from the target volume. In the past 30 years, external-beam treatment technologies have evolved significantly, and a large amount of data exist but appear to be difficult to comprehend and compare. This review article aims to provide readers with an understanding of the principles and methods related to scattered doses in radiation therapy by summarizing a large collection of dosimetry and clinical studies. Basic concepts and terminology are introduced at the beginning. That is followed by a comprehensive review of dosimetry studies for external-beam treatment modalities including classical radiation therapy, 3D-conformal x-ray therapy, intensity-modulated x-ray therapy (IMRT and tomotherapy) and proton therapy. Selected clinical data on second cancer induction among radiotherapy patients are also covered. Problems in past studies and controversial issues are discussed. The needs for future studies are presented at the end.

Treatment-specific risks of second malignancies and cardiovascular disease in 5-year survivors of testicular cancer

PURPOSE

To compare radiotherapy and chemotherapy effects on long-term risks of second malignant neoplasms (SMNs) and cardiovascular diseases (CVDs) in testicular cancer (TC) survivors.

PATIENTS AND METHODS

In our nationwide cohort comprising 2,707 5-year TC survivors, incidences of SMNs and CVDs were compared with general-population rates by calculating standardized incidence ratios (SIRs) and absolute excess risks (AERs). Treatment effects on risks of SMN and CVD were quantified in multivariable Cox regression and competing risks analyses.

RESULTS

After a median follow-up time of 17.6 years, 270 TC survivors developed SMNs. The SIR of SMN overall was 1.7 (95% CI, 1.5 to 1.9), with an AER of 32.3 excess occurrences per 10,000 person-years. SMN risk was 2.6-fold (95% CI, 1.7- to 4.0-fold) increased after subdiaphragmatic radiotherapy and 2.1-fold (95% CI, 1.4- to 3.1-fold) increased after chemotherapy, compared with surgery only. Subdiaphragmatic radiotherapy increased the risk of a major late complication (SMN or CVD) 1.8-fold (95% CI, 1.3- to 2.4-fold), chemotherapy increased the risk of a major late complication 1.9-fold (95% CI, 1.4- to 2.5-fold), and smoking increased the risk of a major late complication 1.7-fold (95% CI, 1.4- to 2.1-fold), compared with surgery only. The median survival time was 1.4 years after SMN and 4.7 years after CVD.

CONCLUSION

Radiotherapy and chemotherapy increased the risk of developing SMN or CVD to a similar extent as smoking. Subdiaphragmatic radiotherapy strongly increases the risk of SMNs but not of CVD, whereas chemotherapy increases the risks of both SMNs and CVDs. Prolonged follow-up after chemotherapy is needed to reliably compare the late complications of radiotherapy and chemotherapy after 20 years.

Treatment-Adjusted Predisposition to Second Malignant Neoplasms After a Solid Cancer in Childhood: A Case-Control Study

Purpose

Previous therapy, genetic susceptibility, and the type of first malignant neoplasm (FMN) are known to be associated with the risk of second malignant neoplasm (SMN) among patients treated for a childhood cancer. The aim of this study was to investigate the independent role of the FMN in the onset of any SMN.

Patients and Methods

A case-control study nested in a European cohort of 4,581 patients treated for a solid cancer during childhood was conducted. One hundred forty-six patients with an SMN and 417 controls were matched for sex, age at FMN, chemotherapy, radiotherapy, the local radiation dose received at the site of SMN for patient cases and at the same site for the matched controls, and follow-up.

Results

A significantly increased risk of developing any SMN was observed after Hodgkin's lymphoma, retinoblastoma, malignant bone tumor, soft tissue sarcoma (STS), and germ cell tumor as FMN, after adjustment for chemotherapy and family cancer syndrome. No significant risk of developing a carcinoma was observed among patients who had developed Hodgkin's lymphoma as FMN. A significantly increased risk of developing a sarcoma was observed among patients who had developed a retinoblastoma (adjusted odds ratio [ORa] = 7.5; 95% CI, 1.2 to 46), a malignant bone tumor (ORa = 13.3; 95% CI, 1.5 to 117), an STS (ORa = 4.8; 95% CI, 1.3 to 18), or a carcinoma (ORa = 9.4; 95% CI, 1.1 to 82) as FMN.

Conclusion

Survivors of Hodgkin's lymphoma, retinoblastoma, malignant bone tumor, STS, and germ cell tumor should receive close surveillance because they are at increased risk of developing any SMN.

Radiotherapy and wound healing

Radiotherapy is an invaluable weapon when treating cancer. However, the deleterious effects of radiation, both immediate and long-term, may have a significant effect on local tissues. Problematic wound healing in radiation-damaged tissue constitutes a major problem that is frequently overlooked during the management of patients who require radiotherapy, or have had radiotherapy in the past. Poor wound healing may lead to chronic ulceration, pain, secondary infection and psychological distress and compromise the outcome of general or reconstructive surgery. We discuss the pathophysiology of poor wound healing following radiotherapy, specific problems for radiation-damaged tissue and potential treatments to improve wound healing of irradiated tissues.

Concomitant chemo-radiotherapy and local dose of radiation as risk factors for second malignant neoplasms after solid cancer in childhood: A case–control study

Radiotherapy and chemotherapy are associated with an increased risk of a second malignant neoplasm (SMN) after a cancer during childhood. This study specified the dose-effect relationship between radiotherapy, chemotherapy and the risk of a SMN, and investigated the effect of chemo-radiotherapy on the risk of SMN. A case-control study nested in a European cohort of 4,581 patients treated for a solid cancer during childhood was conducted. One hundred and fifty three cases with a SMN and 442 controls were matched according to sex, age at first cancer, calendar year, type of first cancer and follow-up. The local radiation dose was estimated at the site of the SMN, for each case and at the same site, for the matched controls. The local dose of radiation significantly increased the risk of a SMN. The best model was linear with an excess relative risk per Gray equal to 0.13 (95% CI, 0.06; 0.26). Any chemotherapy significantly increased the risk of a SMN, odd ratio(adjusted) (OR(adjusted)) = 2.4 (95% confidence interval (95% CI), 1.4-4.1), but no dose-effect relationship was observed between any drug category and the risk of a SMN. Patients who had received concomitant chemo-radiotherapy were significantly more at risk of developing a SMN than patients who had been treated with sequential chemo-radiotherapy, even after adjustment for the local dose of radiation and the 6 most frequently administered drugs, OR(adjusted) = 2.3 (95%CI, 1.1-4.8). Radiation was found to be the foremost treatment-related risk factor for the occurrence of a SMN. Compared to sequential treatment, concomitant chemo-radiotherapy may lead to a higher risk of a SMN.

Risk of melanoma following adulthood cancer: A case-control study

Melanoma is a severe skin cancer related to sun exposure. Whether this malignancy is linked to exposure to ionising radiation during adulthood is still controversial. This case-control study examined the risk of melanoma following treatment for an adulthood first malignant neoplasm (FMN). Cases were patients who presented with cutaneous melanoma after a first cancer in adulthood. Controls (3 per case) were patients free of melanoma, matched for age, duration of follow-up since the FMN, type of FMN, and followed in the same institution. A total of 57 cases and 171 controls were included. In the final multivariate analysis, no risk of melanoma was associated with radiotherapy (odds ratio (OR) for 1 Gy = 1.01, 95% confidence interval (95%CI) 0.96-1.07) nor hormonotherapy, whereas chemotherapy use (OR = 2.3, 95%CI 0.93-5.6) and having a history of familial cancer (OR = 2.8, 95%CI 1.3-5.9) exhibited a nearly significant risk. In conclusion, unlike the evidence for risk of exposure to ionising radiation during childhood, we did not substantiate a risk for association of melanoma with exposure to ionising radiation during adulthood. The risk associated with chemotherapy should justify the implementation of skin surveillance for early detection of melanoma in these patients.

Comparisons of Estimated Economic Burdens due to Insufficient Solar Ultraviolet Irradiance and Vitamin D and Excess Solar UV Irradiance for the United States

Vitamin D sufficiency is required for optimal health, and solar ultraviolet B (UVB) irradiance is an important source of vitamin D. UVB and/or vitamin D have been found in observational studies to be associated with reduced risk for over a dozen forms of cancer, multiple sclerosis, osteoporotic fractures, and several other diseases. On the other hand, excess UV irradiance is associated with adverse health outcomes such as cataracts, melanoma, and nonmelanoma skin cancer. Ecologic analyses are used to estimate the fraction of cancer mortality, multiple sclerosis prevalence, and cataract formation that can be prevented or delayed. Estimates from the literature are used for other diseases attributed to excess UV irradiation, additional cancer estimates, and osteoporotic fractures. These results are used to estimate the economic burdens of insufficient UVB irradiation and vitamin D insufficiency as well as excess UV irradiation in the United States for these diseases and conditions. We estimate that 50,000-63,000 individuals in the United States and 19,000-25,000 in the UK die prematurely from cancer annually due to insufficient vitamin D. The U.S. economic burden due to vitamin D insufficiency from inadequate exposure to solar UVB irradiance, diet, and supplements was estimated at $40-56 billion in 2004, whereas the economic burden for excess UV irradiance was estimated at $6-7 billion. These results suggest that increased vitamin D through UVB irradiance, fortification of food, and supplementation could reduce the health care burden in the United States, UK, and elsewhere. Further research is required to confirm these estimates.