Notably, the growing use of radionuclear technology, especially in diagnostic and therapeutic procedures involving radiation exposure, raises concerns about the health effects of radiation. Although epidemiological studies have provided strong evidence for elevated thyroid cancer risk after radiation exposure in childhood, the risk of thyroid cancer associated with adult exposure remains to be investigated. We conducted a systematic review and meta-analysis of relevant studies on the risk of developing thyroid cancer after radiation exposure in adulthood. The PubMed and Web of Science databases were used to select eligible articles. After screening, a total of 15 studies were identified in which estimates of the standardized incidence ratio (SIR) and the relative risk (RR) of thyroid cancer were available in 8 and 11 studies, respectively. The overall SIR estimated by the random effects model was 2.19 [95% confidence interval (CI), 1.54, 3.10]. Cochran\'s Q test showed significant heterogeneity in the SIRs (Q = 178, P < 0.0001). The overall RR at 10 mGy was 1.0038 (95% CI, 0.9991, 1.0085), with no significant heterogeneity (Q = 9.30, P = 0.5041). The total SIR, as well as that from each study, indicated a statistically significant excess, which could be related to screening bias. Radiation-related thyroid cancer risk was elevated in a few studies; however, the overall estimate of the RR at 10 mGy was not significant. This study demonstrates no strong epidemiological evidence for the risk of thyroid cancer in radiation exposure during adulthood; however, further research is needed.

OBJECTIVE: A Pediatric Normal Tissue Effects in the Clinic (PENTEC) analysis of published investigations of central nervous system (CNS) subsequent neoplasms (SNs), subsequent sarcomas, and subsequent lung cancers in childhood cancer survivors who received radiation therapy (RT) was performed to estimate the effect of RT dose on the risk of SNs and the modification of this risk by host and treatment factors.
METHODS: A systematic literature review was performed to identify data published from 1975 to 2022 on SNs after prior RT in childhood cancer survivors. After abstract review, usable quantitative and qualitative data were extracted from 83 studies for CNS SNs, 118 for subsequent sarcomas, and 10 for lung SNs with 4 additional studies (3 for CNS SNs and 1 for lung SNs) later added. The incidences of SNs, RT dose, age, sex, primary cancer diagnosis, chemotherapy exposure, and latent time from primary diagnosis to SNs were extracted to assess the factors influencing risk for SNs. The excess relative ratio (ERR) for developing SNs as a function of dose was analyzed using inverse-variance weighted linear regression, and the ERR/Gy was estimated. Excess absolute risks were also calculated.
RESULTS: The ERR/Gy for subsequent meningiomas was estimated at 0.44 (95% CI, 0.19-0.68); for malignant CNS neoplasms, 0.15 (95% CI, 0.11-0.18); for sarcomas, 0.045 (95% CI, 0.023-0.067); and for lung cancer, 0.068 (95% CI, 0.03-0.11). Younger age at time of primary diagnosis was associated with higher risk of subsequent meningioma and sarcoma, whereas no significant effect was observed for age at exposure for risk of malignant CNS neoplasm, and insufficient data were available regarding age for lung cancer. Females had a higher risk of subsequent meningioma (odds ratio, 1.46; 95% CI, 1.22-1.76; P < .0001) relative to males, whereas no statistically significant sex difference was seen in risk of malignant CNS neoplasms, sarcoma SNs, or lung SNs. There was an association between chemotherapy receipt (specifically alkylating agents and anthracyclines) and subsequent sarcoma risk, whereas there was no clear association between specific chemotherapeutic agents and risk of CNS SNs and lung SNs.
CONCLUSIONS: This PENTEC systematic review shows a significant radiation dose-response relationship for CNS SNs, sarcomas, and lung SNs. Given the linear dose response, improved conformality around the target volume that limits the high dose volume might be a promising strategy for reducing the risk of SNs after RT. Other host- and treatment-related factors such as age and chemotherapy play a significant contributory role in the development of SNs and should be considered when estimating the risk of SNs after RT among childhood cancer survivors.

Radiation therapy (RT) is a mainstay for the treatment of head and neck (HN) cancers, with 80% of patients receiving such treatment. Radiation-induced malignancies represent a life-threatening long-term effect of RT, with an incidence of 0.5% to 15%.
After 13 years, a 33-year-old woman treated with chemo-radiotherapy for nasopharyngeal carcinoma developed a locally advanced, radiation-induced, p16-negative oropharyngeal squamous cell carcinoma (SCC) at the base of the tongue. Chemo/immunotherapy was administered as a first-line treatment. Given the optimal response and the feasibility of surgery, after three cycles, the patient underwent a total glossectomy, bilateral neck dissection, and reconstruction with a thoraco-dorsal free flap. A histological examination found SCC with a residual cancer burden of 70% and free margins.
The mechanisms responsible for carcinogenesis after RT are still not completely clear. Diagnosis may be challenging due to the previous treatment; growth patterns are unusual, and lymphotropism is lower. Prognosis is usually poor since surgical resectability is often not achievable.
Radiation-induced malignancies are difficult to treat. Patient management should always be discussed at a multidisciplinary level. Future research is needed to assess whether the promising results of clinical studies with pre-operative immunotherapy in locally advanced HN SCC patients may be translated into radiation-induced cancers.

Angiosarcoma (AS) of the breast is very rare, accounting for 1% of all soft tissue breast tumors. AS may present as primary tumors of the breast or as secondary lesions usually associated with previous radiotherapy. Commonly, secondary AS affects older women (median age 67-71 years) with a clinical history of breast cancer. The preferred site of onset of RIAS is the edge of radiation fields, where radiation doses and tumor necrosis may be heterogeneous, resulting in a DNA damage and instability. Radical surgery is the treatment of choice, but no clear consensus exists on surgical management of breast AS.
We describe an atypical case of relapsed RIAS after radical mastectomy, treated with new surgery and, considering the higher risk of recurrence, subsequent adjuvant chemotherapy with weekly paclitaxel.
The frequency of radiation-induced angiosarcomas (RIAS) after breast-conserving surgery and radiotherapy has been increased to 0.14-0.5% among long survivors. Nevertheless, even if RIAS continues to be prognostically an extremely unfavorable cancer due to a high rate of recurrence, distant spread, and median overall survival (OS) of about 60 months, the benefits of loco-regional breast radiotherapy are clearly higher than the risk in developing angiosarcoma.

Solar ultraviolet radiation (UVR) is the most significant occupational carcinogenic exposure in terms of the number of workers exposed (i.e., outdoor workers). Consequently, solar UVR-induced skin cancers are among the most common forms of occupational malignancies that are potentially expected globally. This systematic review is registered in PROSPERO (CRD42021295221) and aims to assess the risk of cutaneous squamous cell carcinoma (cSCC) associated to occupational solar UVR exposure. Systematic searches will be performed in three electronic literature databases (PubMed/Medline, EMBASE, and Scopus). Further references will be retrieved by a manual search (e.g., in grey literature databases, internet search engines, and organizational websites). We will include cohort studies and case-control studies. Risk of Bias assessment will be conducted separately for case-control and cohort studies. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) will be used for the certainty of assessment. In case quantitative pooling is not feasible, a narrative synthesis of results will be performed.

After smoking, residential radon is the second risk factor of lung cancer in general population and the first in never-smokers. Previous studies have analyzed radon attributable lung cancer mortality for some countries. We aim to identify, summarize, and critically analyze the available data regarding the mortality burden of lung cancer due to radon, performing a quality assessment of the papers included, and comparing the results from different countries. We performed a systematic scoping review using the main biomedical databases. We included original studies with attributable mortality data related to radon exposure. We selected studies according to specific inclusion and exclusion criteria. PRISMA 2020 methodology and PRISMA Extension for Scoping Reviews requirements were followed. Data were abstracted using a standardized data sheet and a tailored scale was used to assess quality. We selected 24 studies describing radon attributable mortality derived from 14 different countries. Overall, 13 studies used risk models based on cohorts of miners, 8 used risks from residential radon case-control studies and 3 used both risk model options. Radon geometric mean concentration ranged from 11 to 83 Becquerels per cubic meter (Bq/m3) and the population attributable fraction (PAF) ranged from 0.2 to 26%. Studies performed in radon prone areas obtained the highest attributable mortality. High-quality publications reported PAF ranging from 3 to 12% for residential risk sources and from 7 to 25% for miner risk sources. Radon PAF for lung cancer mortality varies widely between studies. A large part of the variation is due to differences in the risk source used and the conceptual description of radon exposure assumed. A common methodology should be described and used from now on to improve the communication of these results.

BACKGROUND: Secondary meningioma after cranial irradiation, so-called radiation-induced meningioma, is one of the important late effects after cranial radiation therapy. In this report, we analyzed our case series of secondary meningioma after cranial irradiation and conducted a critical review of literature to reveal the characteristics of secondary meningioma.
METHODS: We performed a comprehensive literature review by using Pubmed, MEDLINE and Google scholar databases and investigated pathologically confirmed individual cases. In our institute, we found pathologically diagnosed seven cases with secondary meningioma between 2000 and 2018. Totally, 364 cases were analyzed based on gender, WHO grade, radiation dose, chemotherapy. The latency years from irradiation to development of secondary meningioma were analyzed with Kaplan-Meier analysis. Spearman\'s correlation test was used to determine the relationship between age at irradiation and the latency years.
RESULTS: The mean age at secondary meningioma development was 35.6 ± 15.7 years and the mean latency periods were 22.6 ± 12.1 years. The latency periods from irradiation to the development of secondary meningioma are significantly shorter in higher WHO grade group (P = 0.0026, generalized Wilcoxon test), higher radiation dose group (P < 0.0001) and concomitant systemic chemotherapy group (P = 0.0003). Age at irradiation was negatively associated with the latency periods (r = -0.23231, P < 0.0001, Spearman\'s correlation test).
CONCLUSIONS: Cranial irradiation at older ages, at higher doses and concomitant chemotherapy was associated with a shorter latency period to develop secondary meningiomas. However, even low-dose irradiation can cause secondary meningiomas after a long latency period. Long-term follow-up is necessary to minimize the morbidity and mortality caused by secondary meningioma after cranial irradiation.

BACKGROUND: The so-called radiation-induced glioma (RIG, a secondary glioma after cranial irradiation), is a serious late effect after cranial radiation therapy. The clinical characteristics of and ideal treatment for these tumors are unclear. We analyzed our case series and conducted a comprehensive literature review to reveal the precise characteristics of RIGs.
METHODS: We analyzed the cases of six patients with RIGs treated at our institution and 354 patients with RIGs from the literature. The latency period from irradiation to the development of each RIG and the median overall survival of the patients were subjected to Kaplan-Meier analyses. Spearman\'s correlation test was used to determine the relationship between age at irradiation and the latency period.
RESULTS: The mean age of the 360 patients at the development of RIG was 27.42 ± 17.87 years. The mean latency period was 11.35 ± 8.58 years. Multiple gliomas were observed in 28.4%. WHO grade 3 and 4 RIGs accounted for 93.3%. The latency periods were significant shorter in the higher WHO grade group (p = 0.0366) and the concomitant systemic chemotherapy group (p < 0.0001). Age at irradiation was negatively associated with the latency period (r =- 0.2287, p = 0.0219). The patients treated with radiotherapy achieved significantly longer survival compared to those treated without radiotherapy (p = 0.0011).
CONCLUSIONS: Development in younger age, multiplicity, and high incidence of grade 3 and 4 are the clinical characteristics of RIGs. Cranial irradiation at older ages and concomitant chemotherapy were associated with shorter latency for the development of RIG. Radiation therapy may be the feasible treatment option despite radiation-induced gliomas.

Moderate to high doses of ionizing radiation (IR) are known to increase the risk of cancer, particularly following childhood exposure. Concerns remain regarding risks from lower doses and the role of cancer-predisposing factors (CPF; genetic disorders, immunodeficiency, mutations/variants in DNA damage detection or repair genes) on radiation-induced cancer (RIC) risk. We conducted a systematic review of evidence that CPFs modify RIC risk in young people. Searches were performed in PubMed, Scopus, Web of Science, and EMBASE for epidemiologic studies of cancer risk in humans (<25 years) with a CPF, exposed to low-moderate IR. Risk of bias was considered. Fifteen articles focusing on leukemia, lymphoma, breast, brain, and thyroid cancers were included. We found inadequate evidence that CPFs modify the risk of radiation-induced leukemia, lymphoma, brain/central nervous system, and thyroid cancers and limited evidence that BRCA mutations modify radiation-induced breast cancer risk. Heterogeneity was observed across studies regarding exposure measures, and the numbers of subjects with CPFs other than BRCA mutations were very small. Further studies with more appropriate study designs are needed to elucidate the impact of CPFs on RIC. They should focus either on populations of carriers of specific gene mutations or on common susceptible variants using polygenic risk scores.

Outer space is an extremely hostile environment for human life, with ionizing radiation from galactic cosmic rays and microgravity posing the most significant hazards to the health of astronauts. Spaceflight has also been shown to have an impact on established cancer hallmarks, possibly increasing carcinogenic risk. Terrestrially, women have a higher incidence of radiation-induced cancers, largely driven by lung, thyroid, breast, and ovarian cancers, and therefore, historically, they have been permitted to spend significantly less time in space than men. In the present review, we focus on the effects of microgravity and radiation on the female reproductive system, particularly gynecological cancer. The aim is to provide a summary of the research that has been carried out related to the risk of gynecological cancer, highlighting what further studies are needed to pave the way for safer exploration class missions, as well as postflight screening and management of women astronauts following long-duration spaceflight.