Is the Linear No-Threshold Dose-Response Paradigm Still Necessary for the Assessment of Health Effects of Low Dose Radiation?

Inevitable human exposure to ionizing radiation from man-made sources has been increased with the proceeding of human civilization and consequently public concerns focus on the possible risk to human health. Moreover, Fukushima nuclear power plant accidents after the 2011 East-Japan earthquake and tsunami has brought the great fear and anxiety for the exposure of radiation at low levels, even much lower levels similar to natural background. Health effects of low dose radiation less than 100 mSv have been debated whether they are beneficial or detrimental because sample sizes were not large enough to allow epidemiological detection of excess effects and there was lack of consistency among the available experimental data. We have reviewed an extensive literature on the low dose radiation effects in both radiation biology and epidemiology, and highlighted some of the controversies therein. This article could provide a reasonable view of utilizing radiation for human life and responding to the public questions about radiation risk. In addition, it suggests the necessity of integrated studies of radiobiology and epidemiology at the national level in order to collect more systematic and profound information about health effects of low dose radiation.

Diminished Utilization of in Vitro Fertilization Following Ovarian Transposition in Cervical Cancer Patients.

OBJECTIVE: To assess subsequent utilization of fertility treatment in reproductive-age women with cervical cancer (CC) who underwent ovarian transposition (OT) to preserve fertility prior to pelvic radiation. STUDY DESIGN: This is a case series of 216 CC patients seen in a comprehensive cancer center. Sixteen patients underwent OT for fertility preservation prior to pelvic radiation. Patients were assessed for utilization of fertility treatment, follicle-stimulating hormone (FSH) levels as a measure of ovarian reserve, and functional assessment of chronic illness therapy-cervix cancer (FACT-CX) to assess quality of life after OT. RESULTS: Of the patients, 94% of patients [corrected] maintained regular menstrual cycles 3 years after ovarian transposition (OT) [corrected] surgery (15/16). When measured (n = 5), serum FSH was normal at baseline and showed a transient elevation at 3 months following chemoradiation, with a return to normal levels at 6 months (means, 6.33 ± 2.94, 48.44 ± 18.63, and 12.52 ± 8.25 mIU/mL, respectively). Only 1 patient in this series attempted fertility treatment (in vitro fertilization) following OT, and she did not become pregnant. FACT-CX indicated that quality of life did not change significantly over the 6 months' duration following OT and chemoradiation therapy. CONCLUSION: OT preserves menstrual cycle regularity without negatively impacting patients' quality of life. The utility of OT as an effective fertility preservation option is hampered by the low utilization rate of in vitro fertilization and lack of ovarian reserve assessment following OT.

A phase II study of oxaliplatin, 5-fluorouracil, leucovorin, and high-dose capecitabine in patients with metastatic colorectal cancer.

PURPOSE: Capecitabine has shown similar efficacy to 5-fluorouracil (5-FU); a regimen containing 2 weeks of capecitabine/oxaliplatin (CapOx) has demonstrated noninferiority to infusional 5-FU/oxaliplatin/leucovorin (FOLFOX) for the treatment of metastatic colorectal cancer (mCRC). This phase II study explores the efficacy and safety of a 2-day course of oxaliplatin/capecitabine (2DOC), with oxaliplatin given on day 1 and capecitabine given orally every 8 hours in high doses over 6 doses, mimicking FOLFOX6. PATIENTS AND METHODS: This phase II study was conducted by the University of Wisconsin Carbone Cancer Center. Eligible patients with mCRC received oxaliplatin 100 mg/m2 intravenously (I.V.) over 2 hours followed by leucovorin 20 mg/m2 I.V. bolus and 5-FU 400 mg/m2 I.V. bolus on day 1 and day 15. Capecitabine was administered at 1500 mg/m2 orally every 8 hours over 6 doses starting on day 1 and day 15. RESULTS: A total of 45 patients were enrolled; 44 were evaluated for response. Seventeen patients (39%) had objective responses. Median time to progression was 6.8 months, and median overall survival (OS) was 17.5 months. The most common side effects were grade 1/2 neuropathy, fatigue, and nausea. Severe hand-foot syndrome (HFS) was rare. CONCLUSION: The overall response rate with the 2DOC regimen is similar to published CapOx regimens, and time to progression and OS are similar. The incidence of HFS, diarrhea, and mucositis were lower compared with published results of 2-week schedules of capecitabine. The 2DOC regimen merits further study as a more convenient regimen than infusional 5-FU with less HFS when compared with a 2-week administration of capecitabine.

Aggressive surgical management of peritoneal carcinomatosis with low mortality in a high-volume tertiary cancer center.

BACKGROUND: Cytoreductive surgery (CS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) for treatment of peritoneal carcinomatosis (PC) traditionally involves high perioperative morbidity and mortality. We report our experience performing CS-HIPEC in a high-volume regional perfusion program designed to limit morbidity and mortality. METHODS: A total of 122 patients underwent 124 CS-HIPEC procedures. Common tumors treated with CS-HIPEC included appendiceal (38.5%), colorectal (24.6%), and ovarian cancers (13.1%), and peritoneal mesothelioma (12.3%). Complete cytoreduction was performed in all patients, with organ resections performed as necessary. RESULTS: R0 resection was achieved in 28.7% of cases, R1 in 54.9%, and R2 in 16.4%. Median operative time was 460 minutes (range, 250-840 minutes), and median blood loss was 1150 mL (range, 10-14,000 mL). Median hospital and intensive care unit stays were 12 days (range, 6-50 days) and 3 days (range, 0-41 days), respectively. Grade 3 or 4 morbidity by National Cancer Institute criteria (major morbidity) was seen in 29.8% of cases, with overall morbidity 56.5%. Independent prognostic variables for major morbidity included number of anastomoses and degree of cytoreduction. In-hospital and 30-day mortality rates were 0% and 1.6%, respectively. The most favorable diagnosis was appendiceal cancer, for which 2-year survival was 66.7%, with lower-grade histologic subtypes of appendiceal cancer reaching 85.7% 2-year survival. Colorectal cancer had 2-year survival of 36.7%. CONCLUSIONS: In a high-volume center with extensive experience treating peritoneal malignancies, perioperative mortality can be lowered to nearly zero, although morbidity remains high. CS-HIPEC procedures should be studied further in a controlled manner to help define their important role in the care of patients with PC.