Solid cancer incidence among Chinese medical diagnostic x‐ray workers, 1950–1995: Estimation of radiation‐related risks

The objective of this study was to estimate solid cancer risk attributable to long‐term, fractionated occupational exposure to low doses of ionizing radiation. Based on cancer incidence for the period 1950–1995 in a cohort of 27,011 Chinese medical diagnostic X‐ray workers and a comparison cohort of 25,782 Chinese physicians who did not use X‐ray equipment in their work, we used Poisson regression to fit excess relative risk (ERR) and excess absolute risk (EAR) dose–response models for incidence of all solid cancers combined. Radiation dose reconstruction was based on a previously published method that relied on simulating measurements for multiple X‐ray machines, workplaces and working conditions, information about protective measures, including use of lead aprons, and work histories. The resulting model was used to estimate calendar year‐specific badge dose calibrated as personal dose equivalent (Sv). To obtain calendar year‐specific colon doses (Gy), we applied a standard organ conversion factor. A total of 1,643 cases of solid cancer were identified in 1.45 million person‐years of follow‐up. In both ERR and EAR models, a statistically significant radiation dose–response relationship was observed for solid cancers as a group. Averaged over both sexes, and using colon dose as the dose metric, the estimated ERR/Gy was 0.87 (95% CI: 0.48, 1.45), and the EAR was 22 per 10⁴PY‐Gy (95% CI: 14, 32) at age 50. We obtained estimates of the ERR and EAR of solid cancers per unit dose that are compatible with those derived from other populations chronically exposed to low dose‐rate occupational or environmental radiation.     

Intrathoracic extensive-stage small cell lung cancer: assessment of the benefit of thoracic and brain radiotherapy using the SEER database

Background

Extensive-stage small cell lung cancer (ESCLC) includes metastatic disease and locally advanced disease confined to the thorax that cannot be encompassed in a typical radiation portal. We assessed and then compared the benefits of thoracic radiotherapy (TRT) and/or brain radiotherapy (BRT) on overall survival (OS) between the intrathoracic (T-ESCLC) and metastatic (M-ESCLC) groups using the Surveillance Epidemiology and End Results database.

Methods

TRT and BRT data were available for 10150 patients treated from 1988?1997. The T-ESCLC group included 1774 patients. The Kaplan–Meier method was used to estimate OS and the proportional hazards model was used to estimate OS hazard ratios for prognostic factors including age, gender, race, tumor size, T/N stage, TRT, and BRT.

Results

The 2-year OS for T-ESCLC was 7.8 % compared to 3 % in the M-ESCLC group (p < 0.001). In the T-ESCLC group, TRT and BRT were delivered to 750 and 102 patients, respectively. The 2-year OS was 13 % in the TRT group compared to 4.1 % in the no-TRT group (p ≤ 0.001) and 22.5 % in the BRT group compared to 7 % in the no-BRT group (p < 0.001). In the M-ESCLC group, TRT and BRT were delivered to 3093 and 1887 patients, respectively. The 2-year OS was 4.4 % in the TRT group compared to 2.8 % in the no-TRT group (p < 0.001) and 4.3 % in the BRT compared to 2.6 % in the no-BRT group (p < 0.001). Age, gender, TRT and BRT were significant OS prognostic factors in both groups.

Conclusions

Our study suggests that T-ESCLC is a disease entity distinct from M-ESCLC. Prospective studies to determine whether TRT should be recommended for the thoracic-only subgroup are warranted.

     

Erratum to: Unresectable Hepatocellular Carcinoma: Radioembolization Versus Chemoembolization: A Systematic Review and Meta-analysis

CardioVascular and Interventional Radiology -     

Unresectable Hepatocellular Carcinoma: Radioembolization Versus Chemoembolization: A Systematic Review and Meta-analysis

Background

Transarterial radioembolization (TARE) has emerged as a newer regional therapy to transarterial chemoembolization (TACE) for treatment of unresectable hepatocellular carcinoma (HCC). The aim of this study is to compare clinical outcomes of both the techniques.

Methods

Online search for studies comparing TARE to TACE from 2005 to present was performed. Primary outcome was overall survival rate for up to 4 years. Secondary outcomes included post-treatment complications and treatment response. Quality of included studies was evaluated by STrengthening the Reporting of OBservational studies in Epidemiology criteria. Relative risk (RR) and 95 % confidence intervals (CI) were calculated from pooled data.

Results

The search strategy yielded 172 studies, five met selection criteria and included 553 patients with unresectable HCC, 284 underwent TACE and 269 underwent TARE. Median ages were 63 and 64 years for TACE and TARE, respectively. Meta-analysis showed no statistically significant difference in survival for up to 4 years between the two groups (HR = 1.06; 95 % CI 0.81–1.46, p = 0.567). TACE required at least one day of hospital stay compared to TARE which was mostly an outpatient procedure. TACE had more post-treatment pain than TARE (RR = 0.51, 95 % CI 0.36–0.72, p < 0.01), but less subjective fatigue (RR = 1.68, 95 % CI 1.08–2.62, p < 0.01). There was no difference between the two groups in the incidence of post-treatment nausea, vomiting, fever, or other complications. In addition, there was no difference in partial or complete response rates between the two groups.

Conclusion

TARE appears to be a safe alternative treatment to TACE with comparable complication profile and survival rates. Larger prospective randomized trials, focusing on patient-reported outcomes and cost–benefit analysis are required to consolidate these results.

     

Dosimetric Benefits and Practical Pitfalls of Daily Online Adaptive MRI-Guided Stereotactic Radiation Therapy for Pancreatic Cancer

Purpose

Magnetic resonance imaging guided (MRI-g) radiation therapy provides visualization of the target and organs at risk (OARs), allowing for daily online adaptive radiation therapy (OART). We hypothesized that MRI-g OART would improve OAR sparing and target coverage in patients with pancreatic cancer treated with stereotactic body radiation therapy (SBRT).

Impact of genomic assays on treatment and outcomes in locally advanced breast cancer

Breast Cancer Research and Treatment - Genomic profiling in early-stage breast cancer provides prognostic and predictive information. Genomic profiling assays have not been validated in locally...