Estimation of effective imaging dose and excess absolute risk of secondary cancer incidence for four-dimensional cone-beam computed tomography acquisition.

This study was conducted to estimate the organ equivalent dose and effective imaging dose for four-dimensional cone-beam computed tomography (4D-CBCT) using a Monte Carlo simulation, and to evaluate the excess absolute risk (EAR) of secondary cancer incidence. The EGSnrc/BEAMnrc were used to simulate the on-board imager (OBI) from the TrueBeam linear accelerator. Specifically, the OBI was modeled based on the percent depth dose and the off-center ratio was measured using a three-dimensional (3D) water phantom. For clinical cases, 15 lung and liver cancer patients were simulated using the EGSnrc/DOSXYZnrc. The mean absorbed doses to the lung, stomach, bone marrow, esophagus, liver, thyroid, bone surface, skin, adrenal glands, gallbladder, heart, intestine, kidney, pancreas and spleen, were quantified using a treatment planning system, and the equivalent doses to each organ were calculated. Subsequently, the effective dose was calculated as the weighted sum of the equivalent dose, and the EAR of the secondary cancer incidence was determined for each organ with the use of the biologic effects of ionizing radiation (BEIR) VII model. The effective doses were 3.9 ± 0.5, 15.7 ± 2.0, and 7.3 ± 0.9 mSv, for the lung, and 4.2 ± 0.6, 16.7 ± 2.4, and 7.8 ± 1.1 mSv, for the liver in the respective cases of the 3D-CBCT (thorax, pelvis) and 4D-CBCT modes. The lung EARs for males and females were 7.3 and 10.7 cases per million person-years, whereas the liver EARs were 9.9 and 4.5 cases per million person-years. The EAR increased with increasing time since radiation exposure. In clinical studies, we should use 4D-CBCT based on consideration of the effective dose and EAR of secondary cancer incidence.

Survival disparities for second primary malignancies diagnosed among childhood cancer survivors: A population-based assessment.

BACKGROUND: Curative therapy places childhood cancer survivors at increased risk for second primary malignancies (SPMs). However, there have been few population-based attempts to characterize differences between outcomes of SPMs in childhood cancer survivors and outcomes of first primary malignancies (FPMs). METHODS: Clinical and demographic information about childhood cancer survivors who developed SPMs and individuals with comparable FPMs was extracted from the Surveillance, Epidemiology, and End Results program. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated with Cox proportional hazards models comparing the overall survival (OS) of individuals with and without a history of childhood cancer. OS was evaluated both overall and for specific cancers diagnosed in 50 or more childhood cancer survivors. Models accounted for potential confounders, including sex, race, age, treatment decade, histology, and disease stage. RESULTS: Compared with individuals with FPMs (n = 1,332,203), childhood cancer survivors (n = 1409) with an SPM experienced poorer OS (HR, 1.86; 95% CI, 1.72-2.02) after the study had accounted for cancer type, age, sex, race, and decade of diagnosis. A history of childhood cancer remained a poor prognostic factor for all specific cancers evaluated, including breast cancer (HR, 2.07; 95% CI, 1.63-2.62), thyroid cancer (HR, 3.59; 95% CI, 2.08-6.19), acute myeloid leukemia (HR, 2.38; 95% CI, 1.87-3.05), brain cancer (HR, 2.09; 95% CI, 1.72-2.55), melanoma (HR, 2.57; 95% CI, 1.55-4.27), bone cancer (HR, 1.88; 95% CI, 1.37-2.57), and soft-tissue sarcoma (HR, 2.44; 95% CI, 1.78-3.33). CONCLUSIONS: Compared with individuals without a prior cancer diagnosis, survivors of childhood cancer with an SPM experienced inferior outcomes. Survival disparities were observed for the most frequent SPMs diagnosed in childhood cancer survivors.

Colorectal cancer surveillance in Hodgkin lymphoma survivors at increased risk of therapy-related colorectal cancer: study design.

BACKGROUND: Second primary malignancies are a major cause of excess morbidity and mortality in cancer survivors. Hodgkin lymphoma survivors who were treated with infradiaphragmatic radiotherapy and/or high-dose procarbazine have an increased risk to develop colorectal cancer. Colonoscopy surveillance plays an important role in colorectal cancer prevention by removal of the precursor lesions (adenomas) and early detection of cancer, resulting in improved survival rates. Therefore, Hodgkin lymphoma survivors treated with infradiaphragmatic radiotherapy and/or high-dose procarbazine could benefit from colonoscopy, or other surveillance modalities, which are expected to reduce colorectal cancer incidence and mortality. Current knowledge on clinicopathological and molecular characteristics of therapy-related colorectal cancer is limited. The pathogenesis of such colorectal cancers might be different from the pathogenesis in the general population and therefore these patients might require a different clinical approach. We designed a study with the primary aim to assess the diagnostic yield of a first surveillance colonoscopy among Hodgkin lymphoma survivors at increased risk of colorectal cancer and to compare these results with different screening modalities in the general population. Secondary aims include assessment of the test characteristics of stool tests and evaluation of burden, acceptance and satisfaction of CRC surveillance through two questionnaires. METHODS/DESIGN: This prospective multicenter cohort study will include Hodgkin lymphoma survivors who survived ≥8 years after treatment with infradiaphragmatic radiotherapy and/or procarbazine (planned inclusion of 259 participants). Study procedures will consist of a surveillance colonoscopy with removal of precursor lesions (adenomas) and 6-8 normal colonic tissue biopsies, a fecal immunochemical test and a stool DNA test. All neoplastic lesions encountered will be classified using relevant histomorphological, immunohistochemical and molecular analyses in order to obtain more insight into colorectal carcinogenesis in Hodgkin lymphoma survivors. The Miscan-model will be used for cost-effectiveness analyses. DISCUSSION: Evaluation of the diagnostic performance, patient acceptance and burden of colorectal cancer surveillance is necessary for future implementation of an individualized colorectal cancer surveillance program for Hodgkin lymphoma survivors. In addition, more insight into treatment-induced colorectal carcinogenesis will provide the first step towards prevention and personalized treatment. This information may be extrapolated to other groups of cancer survivors. TRIAL REGISTRATION: Registered at the Dutch Trial Registry (NTR): NTR4961 .

Need For Improved Skin Cancer Surveillance in Pediatric Cancer Survivors.

Survivors of pediatric cancer are at increased risk of developing secondary malignancies, with non-melanoma skin cancer being the most common. These patients are also at increased risk of melanoma. Currently, guidelines provided by the National Cancer Institute and Children's Oncology Group emphasize the importance of annual clinical examination for skin cancer screening; however, the literature reports that less than one-third of survivors of pediatric cancer have ever had a clinical skin exam by a physician. In this article, we review the risk factors for skin cancer in survivors of pediatric cancer as well as the current evidence and recommendations for their care. We suggest that dermatologists collectively establish guidelines for skin cancer surveillance in survivors of pediatric cancer.

Cost-effectiveness of alternative colonoscopy surveillance strategies to mitigate metachronous colorectal cancer incidence.

BACKGROUND: The incidence of metachronous colorectal cancer (MCRC) among colorectal cancer (CRC) survivors varies significantly, and the optimal colonoscopy surveillance practice for mitigating MCRC incidence is unknown. METHODS: A cost-effectiveness analysis was used to compare the performances of the US Multi-Society Task Force guideline and all clinically reasonable colonoscopy surveillance strategies for 50- to 79-year-old posttreatment CRC patients with a computer simulation model. RESULTS: The US guideline [(1,3,5)] recommends the first colonoscopy 1 year after treatment, whereas the second and third colonoscopies are to be repeated at 3- and 5-year intervals. Some promising alternative cost-effective strategies were identified. In comparison with the US guideline, under various scenarios for a 20-year period, 1) reducing the surveillance interval of the guideline after the first colonoscopy by 1 year [(1,2,5)] would save up to 78 discounted life-years (LYs) and prevent 23 MCRCs per 1000 patients (incremental cost-effectiveness ratio [ICER] ≤ $23,270/LY), 2) reducing the intervals after the first and second negative colonoscopies by 1 year [(1,2,4)] would save/prevent up to 109 discounted LYs and 36 MCRCs (ICER ≤ $52,155/LY), and 3) reducing the surveillance intervals after the first and second negative colonoscopy by 1 and 2 years [(1,2,3)] would save/prevent up to 141 discounted LYs and 50 MCRCs (ICER ≤ $63,822/LY). These strategies would require up to 1100 additional colonoscopies per 1000 patients. Although the US guideline might not be cost-effective in comparison with a less intensive oncology guideline [(3,3,5); the ICER could be as high as $140,000/LY], the promising strategies would be cost-effective in comparison with such less intensive guidelines unless the cumulative MCRC incidence were very low. CONCLUSIONS: The US guideline might be improved by a slight increase in the surveillance intensity at the expense of moderately increased cost. More research is warranted to explore the benefits/harms of such practices. Cancer 2016;122:2560-70. © 2016 American Cancer Society.

Myelodysplastic syndromes following therapy with hypomethylating agents (HMAs): development of acute erythroleukemia may not influence assessment of treatment response.

This study followed 28 patients with myelodysplastic syndromes (MDS) who showed a rise of bone marrow (BM) erythroids to ≥ 50% following three cycles (1-60) of hypomethylating agent (HMA) therapy. If BM blasts were calculated as a percentage of non-erythroids, 12 (42.9%) patients met the diagnostic criteria for acute erythroleukemia, erythroid/myeloid (AEL). However, none of the patients showed clonal cytogenetic evolution or new mutations. When compared to 47 de novo AEL patients, these 12 patients were less anemic and thrombocytopenic, had less complex karyotypes (p = 0.044) and showed a longer survival, either calculated from diagnosis (p < 0.001) or from the time of AEL (p = 0.005). These findings illustrate that ≥ 50% erythroids may appear in BM post-HMA therapy, likely a combination of reduction of BM granulocytes (p < 0.001) and promotion of normal or abnormal erythroid proliferation. Enumeration of blasts as a percentage of non-erythroid cells may lead to a diagnosis of AEL and mis-interpretation as disease progression.

Risk Factors for Melanoma Among Survivors of Non-Hodgkin Lymphoma.

PURPOSE: Previous studies have reported that survivors of non-Hodgkin lymphoma (NHL) have an increased risk of developing cutaneous melanoma; however, risks associated with specific treatments and immune-related risk factors have not been quantified. PATIENTS AND METHODS: We evaluated second melanoma risk among 44,870 1-year survivors of first primary NHL diagnosed at age 66 to 83 years from 1992 to 2009 and included in the Surveillance, Epidemiology, and End Results-Medicare database. Information on NHL treatments, autoimmune diseases, and infections was derived from Medicare claims. RESULTS: A total of 202 second melanoma cases occurred among survivors of NHL, including 91 after chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and 111 after other NHL subtypes (cumulative incidence by age 85 years: CLL/SLL, 1.37%; other NHL subtypes, 0.78%). Melanoma risk after CLL/SLL was significantly increased among patients who received infused fludarabine-containing chemotherapy with or without rituximab (n=18: hazard ratio [HR], 1.92; 95% CI, 1.09 to 3.40; n=10: HR, 2.92; 95% CI, 1.42 to 6.01, respectively). Significantly elevated risks also were associated with T-cell activating autoimmune diseases diagnosed before CLL/SLL (n=36: HR, 2.27; 95% CI, 1.34 to 3.84) or after CLL/SLL (n=49: HR, 2.92; 95% CI, 1.66 to 5.12). In contrast, among patients with other NHL subtypes, melanoma risk was not associated with specific treatments or with T-cell/B-cell immune conditions. Generally, infections were not associated with melanoma risk, except for urinary tract infections (CLL/SLL), localized scleroderma, pneumonia, and gastrohepatic infections (other NHLs). CONCLUSION: Our findings suggest immune perturbation may contribute to the development of melanoma after CLL/SLL. Increased vigilance is warranted among survivors of NHL to maximize opportunities for early detection of melanoma.

Role of imaging in testicular cancer: current and future practice.

The article provides a summary of the epidemiologic and clinical aspects of testicular malignancy. Current standard imaging and novel techniques are reviewed. Present data and clinical treatment trends have favored surveillance protocols over adjuvant radiation or chemotherapy for low-stage testicular malignancy. This has resulted in increasing numbers of imaging studies and the potential for increased long-term exposure risks. Understanding imaging associated risks as well as strategies to minimize these risks is of increasing importance. The development, validation and incorporation of alternative lower risk highly efficacious and cost-effective imaging techniques is essential.

Correlation between mutational status and survival and second cancer risk assessment in patients with gastrointestinal stromal tumors: a population-based study.

BACKGROUND: Gastrointestinal stromal tumors are sarcomas of the digestive tract characterized by mutations mainly located in the c-KIT or in the platelet-derived growth factor receptor (PDGFR)-alpha genes. Mutations in the BRAF gene have also been described. Our purpose is to define the distribution of c-KIT, PDGFR and BRAF mutations in a population-based cohort of gastrointestinal stromal tumors (GIST) patients and correlate them with anatomical site, risk classification and survival. In addition, as most of the GIST patients have a long survival, second cancers are frequently diagnosed in them. We performed a second primary cancer risk assessment. METHODS: Our analysis was based on data from Tarragona and Girona Cancer Registries. We identified all GIST diagnosed from 1996 to 2006 and performed a mutational analysis of those in which paraffin-embedded tissue was obtained. Observed (OS) and relative survival (RS) were calculated according to risk classifications and mutational status. Multivariate analysis of variables for observed survival and was also done. RESULTS: A total of 132 GIST cases were found and we analyzed mutations in 108 cases. We obtained 53.7% of mutations in exon 11 and 7.4% in exon 9 of c-KIT gene; 12% in exon 18 and 1.9% in exon 12 of PDGFR gene and 25% of cases were wild type GIST. Patients with mutations in exon 11 of the c-KIT gene had a 5-year OS and RS of 59.6% and 66.3%, respectively. Patients with mutations in exon 18 of the PDGFR gene had a 5-year OS and RS of 84.6% and 89.7%. In multivariate analysis, only age and risk group achieved statistical significance for observed survival. GIST patients had an increased risk of second cancer with a hazard ratio of 2.47. CONCLUSIONS: This population-based study shows a spectrum of mutations in the c-KIT and PDGFR genes in GIST patients similar to that previously published. The OS and RS of GIST with the exon 18 PDGFR gene mutation could indicate that this subgroup of patients may be less aggressive and have a good prognosis, although less sensitive to treatment at recurrence. In our study, GIST patients have an increased risk of developing a second neoplasm.

Childhood Cancer Survivor Study participants' perceptions and understanding of the Affordable Care Act.

PURPOSE: The Patient Protection and Affordable Care Act (ACA) established provisions intended to increase access to affordable health insurance and thus increase access to medical care and long-term surveillance for populations with pre-existing conditions. However, childhood cancer survivors' coverage priorities and familiarity with the ACA are unknown. METHODS: Between May 2011 and April 2012, we surveyed a randomly selected, age-stratified sample of 698 survivors and 210 siblings from the Childhood Cancer Survivor Study. RESULTS: Overall, 89.8% of survivors and 92.1% of siblings were insured. Many features of insurance coverage that survivors considered "very important" are addressed by the ACA, including increased availability of primary care (94.6%), no waiting period before coverage initiation (79.0%), and affordable premiums (88.1%). Survivors were more likely than siblings to deem primary care physician coverage and choice, protections from costs due to pre-existing conditions, and no start-up period as "very important" (P < .05 for all). Only 27.3% of survivors and 26.2% of siblings reported familiarity with the ACA (12.1% of uninsured v 29.0% of insured survivors; odds ratio, 2.86; 95% CI, 1.28 to 6.36). Only 21.3% of survivors and 18.9% of siblings believed the ACA would make it more likely that they would get quality coverage. Survivors' and siblings' concerns about the ACA included increased costs, decreased access to and quality of care, and negative impact on employers and employees. CONCLUSION: Although survivors' coverage preferences match many ACA provisions, survivors, particularly uninsured survivors, were not familiar with the ACA. Education and assistance, perhaps through cancer survivor navigation, are critically needed to ensure that survivors access coverage and benefits.

Risk assessment of second primary cancer according to histological subtype of non-Hodgkin lymphoma.

Non-Hodgkin lymphoma (NHL) represents a heterogeneous group of diseases that are known to carry a considerable risk of second primary cancer (SPC). However, little attention has been paid to SPC risk assessment according to NHL subtypes. Data from 10 French population-based cancer registries were used to establish a cohort of 7546 patients with a first diagnosis of NHL (eight subtypes) between 1989 and 2004. Standardized incidence ratios (SIRs) of metachronous SPC were estimated. Among the 7546 patients diagnosed with a NHL, the overall SPC risk was 25% higher than that in the reference population (SIR = 1.25, 95% confidence interval 1.15-1.36). In univariate analysis, the SPC risk differed by lymphoma subtype. Interestingly, multivariate analysis showed that SPC risk did not differ significantly across NHL subtypes after adjustment for the other covariates (p = 0.786). Patients with NHL have an increased risk of SPC that is not influenced by the histological NHL subtype.

Impact of incidental findings on integrated 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography in patients with gastric cancer.

AIM: Since positron emission tomography/computed tomography (PET/CT) has been introduced, many incidental findings have been identified. The aim of this study was to assess the clinical significance of incidental findings on PET/CT in patients with gastric cancer. METHODS: A total of 421 patients with gastric cancer underwent PET/CT for initial staging. Incidental findings on PET/CT were classified into five categories according to clinical significance--normal variant, benign, probably benign, probably malignant, and definitely malignant. We obtained information regarding follow-up examinations, additional visits, final diagnosis of incidental findings and short-term medical costs for further evaluation. RESULTS: Eight hundred eighty-two incidental findings were detected in 386 (91.7%) patients. Of 274 incidental findings classified as probably benign, probably malignant or definitely malignant, 130 required one or more additional investigations. Finally, 12 (9.2%) were proved to be associated with second primary malignancy or metastasis of gastric cancer. One hundred twenty-nine additional outpatient visits and 10 additional hospitalizations were needed for evaluating the incidental findings. The treatment strategy for gastric cancer was changed in one patient. The estimated cost of additional investigations was $US283 (95% CI: $US248-$US311) per patient. CONCLUSION: Incidental findings on PET/CT were common. Although the incidental findings were suspicious of malignancy, most were benign with high costs for additional investigations.

Treatment strategy for main duct intraductal papillary mucinous neoplasms of the pancreas based on the assessment of recurrence in the remnant pancreas after resection: a retrospective review.

OBJECTIVES: To clarify the recurrence pattern after resection of main duct intraductal papillary mucinous neoplasms (MD-IPMNs) using molecular analyses and determine the most adequate treatment strategy. BACKGROUND: The most appropriate resection line for MD-IPMNs remains an unresolved issue. METHODS: Medical records of 56 patients with pancreatectomy were retrospectively reviewed. Histological subtypes and Kras/GNAS mutations were assessed in patients with recurrence in the remnant pancreas. RESULTS: Forty-nine patients underwent partial pancreatectomy and 7 underwent total pancreatectomy. Thirty-six patients (64%) had malignant MD-IPMNs. Recurrence was observed in 7 of 49 patients (14%), including 6 with malignant IPMNs and 1 with pancreatic ductal adenocarcinoma, all of whom underwent remnant pancreatectomy. The cumulative disease-specific survival rate of patients with pancreatic recurrence was greater than that of patients with extrapancreatic recurrence (P < 0.001). Although the pancreatic margin status at the initial operation did not affect the pancreatic recurrence rate, all 4 recurrent IPMNs examined had histological subtypes and Kras/GNAS mutations identical to those of the initial lesions. Four patients experienced recurrence in the remnant pancreas or systemic recurrence after resection of high-grade dysplasia of MD-IPMN. Three of the 56 patients had concomitant pancreatic ductal adenocarcinomas and MD-IPMNs. CONCLUSIONS: One-step total pancreatectomy can be avoided, and remnant total pancreatectomy would lead to favorable outcomes even in patients with pancreatic recurrence, some cases of which seem to involve residual lesions. Postoperative surveillance of high-grade dysplasia should be performed as if malignant, and close attention should be paid to the occurrence of concomitant pancreatic ductal adenocarcinomas in patients with MD-IPMNs.

Changing trends in the presentation of colorectal liver metastases in a single hepatobiliary tertiary referral centre over fourteen years.

AIM: National Institute for Clinical Excellence guidelines suggest that patients who have undergone potentially curative treatment for colorectal cancer (CRC) should be followed up for 3 years. The aim of this study was to investigate whether the time to presentation with colorectal liver metastases (CRLM) has changed over time. This information, which is currently unknown, may inform future decisions regarding follow-up. METHODS: Patients presenting with metachronous isolated liver metastases between 1997 and 2011 were included. Timings of presentation with CRLM, rates of liver resection, survival data and factors associated with delayed presentation were investigated. RESULTS: 269 patients were included in the study. Those having their primary CRC resection between 1997 and 2007 presented earlier with liver metastases over time (r = -0.33, 95% CI -0.45 to -0.20). However, 26% of patients who developed CRLM did so beyond 3 years. There was no significant difference in rates of liver resections for those presenting within, or beyond, 3 years (p = 0.21). There was no significant difference in survival for those presenting with resectable CRLM within, or beyond, 3 years (Exp(b) = 0.60, 95% CI 0.28-1.28). No factors associated with late presentation were identified. CONCLUSIONS: These results suggest that CRC follow-up should be extended to 5 years. Follow-up interventions should be more frequent in the early stages reflecting the trend towards earlier presentation with CRLM. The economic implications of extending follow-up compare favourably to other NHS funded initiatives.

Sociooccupational and physical outcomes more than 20 years after the diagnosis of osteosarcoma in children and adolescents: limb salvage versus amputation.

BACKGROUND: To the best of the authors' knowledge, there has been relatively little research published to date regarding very long-term survivors of childhood and adolescent osteosarcoma. In the current study, the authors compared the very long-term survival outcomes of patients with osteosarcoma who were treated with either limb salvage procedures or amputation. METHODS: A total of 38 patients with osteosarcoma who survived ≥ 20 years from the time of diagnosis were divided into 2 groups according to whether they underwent amputation or limb salvage. Participants were asked to complete a questionnaire concerning their education, employment, annual income, marital status, health insurance, lifestyle, siblings, and all current and past health issues. RESULTS: Education, employment, marital status, and health insurance were not found to differ significantly between the 2 groups of survivors, who described themselves as being similar to their siblings. Eight percent of survivors underwent secondary amputation because of complications with an endoprosthesis. The cumulative incidence of second primary neoplasms was 13%, and this finding was significantly higher in females and in survivors who underwent radiotherapy and had a genetic predisposition. The second primary malignancies were breast cancer (ductal invasive carcinoma, ductal in situ carcinoma, and leiomyosarcoma), mediastinal leiomyosarcoma, and squamocellular carcinoma of the oral cavity and the uterine cervix. Amputees required more assistive walking support than survivors who received limb salvage treatment (P<.05, chi-square test). CONCLUSIONS: Despite the many challenges that osteosarcoma survivors face, patients who survived ≥ 20 years after their initial diagnosis reported having overall adjusted well to their physical limitations and were productive individuals.

What is the most practical, optimal, and cost effective method for performing follow-up after lung cancer surgery, and by whom should it be done?

Surgery is the treatment of choice for early stage non-small cell lung cancer. In this context, postoperative follow-up is important to diagnose late postoperative complications, as well as to detect recurring cancer or new primaries as early as possible. There is, however, no high-quality evidence regarding the benefits of monitoring programs on survival and quality of life. Most studies recommend clinical and radiological follow-up (radiograph or chest computed tomography) performed more intensively during the first two years and annually thereafter. The physician doing the follow-up can be the thoracic surgeon, the diagnosing physician, or the family physician.

Time trend of multiple myeloma and associated secondary primary malignancies in Asian patients: a Taiwan population-based study.

Studies involving second malignancies in patients with multiple myeloma are limited for the Asian population. Using data from population-based insurance claims, we assessed the risk of developing secondary malignancies after multiple myeloma, in particular hematologic malignancies. A retrospective cohort study was conducted in 3970 patients with newly diagnosed multiple myeloma from the registry of catastrophic illnesses between 1997 and 2009. A total of 15880 subjects without multiple myeloma were randomly selected as comparisons from the insured population, frequency-matched based on gender, age, and the date of diagnosis. The incidence of secondary malignancies was ascertained through cross-referencing with the National Cancer Registry System. The Cox proportional hazards model was used for analyses. The incidence of multiple myeloma in the insured population increased annually. The overall incidence of secondary malignancy was lower in the multiple myeloma cohort than in the comparison cohort (93.6 vs. 104.5 per 10,000 person-years, IRR = 0.90, 95% CI = 0.78-1.04). The incidence of hematologic malignancies was 11-fold greater for multiple myeloma patients (47.2 vs. 4.09 per 10,000 person-years) with an adjusted HR of 13.0 (95% CI = 7.79-21.6) compared with the comparison cohort. The relative risk of secondary malignancy was also strong for myeloid leukemia (21.2 vs. 1.36 per 10,000 person-years). Gender- and age-specific analysis for secondary hematologic malignancies showed that males and patients with multiple myeloma <60 years of age had a higher risk of secondary malignancy than females and patients with multiple myeloma >60 years of age. In conclusion, patients with multiple myeloma, especially younger patients, are at a high risk of hematologic malignancies.

Assessment of recurrence of non-small cell lung cancer after therapy using CT and Integrated PET/CT.

INTRODUCTION: Non-small cell lung cancer (NSCLC) has become the leading cause of cancer-related deaths in Poland. Follow-up of patients with NSCLC is aimed at early detection of local recurrence, metastatic process, treatment-related complications or second primary lung cancer. We investigated the diagnostic accuracy of FDG-PET-CT in the detection of recurrence of NSCLC after treatment. MATERIAL AND METHODS: Seventy-two NSCLC patients (19 females, 56 males), stage I to IV, who had undergone surgery and/ /or radiation therapy, occasionally associated with chemotherapy, were retrospectively included in our study. Chest radiographs and thoracic computed tomography (CT) were performed to localize the abnormality prior to PET-CT. All the patients underwent CT and PET-CT in the period from January 2008 until January 2012. All PET images were interpreted in conjunction with thoracic CT. PET-CT and CT diagnoses were correlated with pathological diagnoses. RESULTS: Forty-five patients had recurrent tumour. Tumour recurrence was observed more often in men than in women and also in case of neoplastic cell emboli in lymphatic or blood vessels. In three patients second primary lung cancer was diagnosed. False positive diagnosis of relapse based on PET-CT was obtained in 4 patients, mainly due to inflammatory lesions. The accuracy of PET-CT for diagnosis of recurrence was 94.4% (95% CI 91; 100). CONCLUSIONS: FDG PET-CT was the best method to differentiate recurrent bronchogenic carcinoma from inflammatory lesions, especially at post-therapeutic sites. It has been shown that PET-CT is more accurate method than CT in recurrent NSCLC. PET-CT results had a further impact on the clinical management and treatment planning.

Imaging doses and secondary cancer risk from kilovoltage cone-beam CT in radiation therapy.

The authors assessed the radiation-induced cancer risk due to organ doses from kilovoltage (kV) cone beam computed tomography (CBCT), a verification technique in image-guided radiotherapy (IGRT). CBCTs were performed for three different treatment sites: the head and neck, chest, and pelvis. Using a glass dosimeter, primary doses versus depth were measured inside a homemade phantom, and organ doses were measured at various locations inside an anthropomorphic phantom. The excess relative risk (ERR), excess absolute risk (EAR), and lifetime attributable risk (LAR) for cancer induction were estimated using the BEIR VII models based on dose measurement. The average primary (i.e., in-field) doses at the center of the phantom for standard imaging options were 1.9, 5.1, and 16.7 cGy for the head and neck, chest, and pelvis, respectively. The average secondary dose per scan for the pelvis measured 20-50 cm from the isocenter and ranged from 0.67-0.02 cGy, whereas the secondary dose per scan for the head and neck ranged from 0.07-0.003 cGy, indicating that CBCT for treatment of the head and neck is associated with a smaller secondary radiation dose than CBCT for treatment of the pelvis. The estimation of LAR from CBCT in IGRT indicated that the lifetime cancer risk for major organs can reach approximately 400 per 10,000 persons if 30 CBCT scans are performed to position a patient during radiation treatment of the pelvis site.

Comparison of risk of radiogenic second cancer following photon and proton craniospinal irradiation for a pediatric medulloblastoma patient.

Pediatric patients who received radiation therapy are at risk of developing side effects such as radiogenic second cancer. We compared proton and photon therapies in terms of the predicted risk of second cancers for a 4 year old medulloblastoma patient receiving craniospinal irradiation (CSI). Two CSI treatment plans with 23.4 Gy or Gy (RBE) prescribed dose were computed: a three-field 6 MV photon therapy plan and a four-field proton therapy plan. The primary doses for both plans were determined using a commercial treatment planning system. Stray radiation doses for proton therapy were determined from Monte Carlo simulations, and stray radiation doses for photon therapy were determined from measured data. Dose-risk models based on the Biological Effects of Ionization Radiation VII report were used to estimate the risk of second cancer in eight tissues/organs. Baseline predictions of the relative risk for each organ were always less for proton CSI than for photon CSI at all attained ages. The total lifetime attributable risk of the incidence of second cancer considered after proton CSI was much lower than that after photon CSI, and the ratio of lifetime risk was 0.18. Uncertainty analysis revealed that the qualitative findings of this study were insensitive to any plausible changes of dose-risk models and mean radiation weighting factor for neutrons. Proton therapy confers lower predicted risk of second cancer than photon therapy for the pediatric medulloblastoma patient.