Utility of the ACE Inhibitor Captopril in Mitigating Radiation-associated Pulmonary Toxicity in Lung Cancer: Results From NRG Oncology RTOG 0123

OBJECTIVES

The primary objective of NRG Oncology Radiation Therapy Oncology Group 0123 was to test the ability of the angiotensin-converting enzyme inhibitor captopril to alter the incidence of pulmonary damage after radiation therapy for lung cancer; secondary objectives included analyzing pulmonary cytokine expression, quality of life, and the long-term effects of captopril.

MATERIALS AND METHODS

Eligible patients included stage II-IIIB non-small cell lung cancer, stage I central non-small cell lung cancer, or limited-stage small cell. Patients who met eligibility for randomization at the end of radiotherapy received either captopril or standard care for 1 year. The captopril was to be escalated to 50 mg three times a day. Primary endpoint was incidence of grade 2+ radiation-induced pulmonary toxicity in the first year.

RESULTS

Eighty-one patients were accrued between June 2003 and August 2007. Given the low accrual rate, the study was closed early. No significant safety issues were encountered. Eight patients were ineligible for registration or withdrew consent before randomization and 40 patients were not randomized postradiation. Major reasons for nonrandomization included patients' refusal and physician preference. Of the 33 randomized patients, 20 were analyzable (13 observation, 7 captopril). The incidence of grade 2+ pulmonary toxicity attributable to radiation therapy was 23% (3/13) in the observation arm and 14% (1/7) in the captopril arm.

CONCLUSIONS

Despite significant resources and multiple amendments, NRG Oncology Radiation Therapy Oncology Group 0123 was unable to test the hypothesis that captopril mitigates radiation-induced pulmonary toxicity. It did show the safety of such an approach and the use of newer angiotensin-converting enzyme inhibitors started during radiotherapy may solve the accrual problems.

Randomized phase III trial to evaluate radiopharmaceuticals and zoledronic acid in the palliation of osteoblastic metastases from lung, breast, and prostate cancer: report of the NRG Oncology RTOG 0517 trial

BACKGROUND

Skeletal-related events (SREs), common sequelae of metastatic cancer, are reduced by bisphosphonates. In this study, it was postulated that radiopharmaceuticals, added to bisphosphonates, could further decrease the incidence of SREs.

METHODS

NRG Oncology RTOG 0517 randomized patients with breast, lung, and prostate cancer and blastic bone metastases to either zoledronic acid (ZA) alone or ZA plus radiopharmaceuticals (Sr-89 or Sm-153). The primary endpoint was time to development of SREs. Secondary objectives included quality of life (QOL), pain control, overall survival (OS), and toxicity.

RESULTS

261 patients (median age 68; 62% male; 55% prostate, 35% breast, 10% lung) were accrued between July 2006 and February 2011. The study closed early due to a lower than expected rate of SREs. 52 (42%) patients in the ZA arm and 49 (40%) in the radiopharmaceutical arm experienced an SRE. Median time free of SREs was 29.9 and 27.4 months, respectively (p = 0.84). Median OS in the ZA arm and radiopharmaceutical arms was 32.1 and 26.9 months, respectively (p = 0.37). Cox proportional hazards regression model showed that primary disease site (lung) and number of bone metastases (> 2) had a negative impact on OS (p < 0.0001, p = 0.01, respectively). The addition of radiopharmaceuticals to ZA led to a significant reduction in pain at 1 month based on BPI worst score (p = 0.02). No other group differences were noted for QOL or toxicity.

CONCLUSION

The addition of radiopharmaceuticals to bisphosphonates did not alter time to SREs or OS for patients with breast, lung, prostate cancers and blastic bone metastases, although it was associated with significant pain reduction at 1 month.

CLINICAL TRIAL REGISTRY

This protocol (RTOG 0517) is registered with ClinicalTrials.gov (NCT00365105), and may be viewed online at http://www.clinicaltrials.gov/ct2/show/NCT00365105?term=RTOG+0517&rank=1 .

A Randomized Phase 2 Trial of Prophylactic Manuka Honey for the Reduction of Chemoradiation Therapy-Induced Esophagitis During the Treatment of Lung Cancer: Results of NRG Oncology RTOG 1012

PURPOSE

Randomized trials have shown that honey is effective for the prevention of radiation-induced mucositis in head and neck cancer patients. Because there is no efficacious preventative for radiation esophagitis in lung cancer patients, this trial compared liquid honey, honey lozenges, and standard supportive care for radiation esophagitis.

METHODS

The patients were stratified by percentage of esophagus receiving specific radiation dose (V60 Gy esophagus <30% or ≥30%) and were then randomized between supportive care, 10 mL of liquid manuka honey 4 times a day, and 2 lozenges (10 mL of dehydrated manuka honey) 4 times a day during concurrent chemotherapy and radiation therapy. The primary endpoint was patient-reported pain on swallowing, with the use of an 11-point (0-10) scale at 4 weeks (Numerical Rating Pain Scale, NRPS). The study was designed to detect a 15% relative reduction of change in NRPS score. The secondary endpoints were trend of pain over time, opioid use, clinically graded and patient-reported adverse events, weight loss, dysphagia, nutritional status, and quality of life.

RESULTS

53 patients were randomized to supportive care, 54 were randomized to liquid honey, and 56 were randomized to lozenge honey. There was no significant difference in the primary endpoint of change in the NRPS at 4 weeks between arms. There were no differences in any of the secondary endpoints except for opioid use at 4 weeks during treatment between the supportive care and liquid honey arms, which was found to be significant (P=.03), with more patients on the supportive care arm taking opioids.

CONCLUSION

Honey as prescribed within this protocol was not superior to best supportive care in preventing radiation esophagitis. Further testing of other types of honey and research into the mechanisms of action are needed.

Significance of Co-expression of Epidermal Growth Factor Receptor and Ki67 on Clinical Outcome in Patients With Anal Cancer Treated With Chemoradiotherapy: An Analysis of NRG Oncology RTOG 9811

PURPOSE

To measure co-expression of EGFR and Ki67 proteins in pretreatment tumor biopsies of anal cancer patients enrolled on NRG Oncology RTOG 9811, a phase III trial comparing 5-fluorouracil/mitomycin-C/radiation therapy (Arm A) versus 5-fluorouracil/cisplatin/radiation therapy (Arm B), and to correlate expression with clinical outcome.

METHODS AND MATERIALS

EGFR and Ki67 co-expression was measured after constructing a tissue microarray using fluorescence immunohistochemistry and automated quantitative image analysis. The Ki67 score within EGFR high versus low areas (Ki67ratio in EGFR_high:low) in each tumor core was analyzed at the median, quartiles, and as a continuous variable. Associations between the tumor markers and clinical endpoints (overall and disease-free survival, locoregional and colostomy failure, and distant metastases) were explored.

RESULTS

A total of 282 pretreatment tumors were analyzed from NRG Oncology RTOG 9811. Of evaluated specimens, 183 (65%, n=89, Arm A; n=94, Arm B) were eligible and analyzable. There were no significant differences in baseline characteristics or outcomes between analyzable and unanalyzable patient cases. Median follow-up was 6.0 years. On multivariate analysis, after adjusting for gender, patients with Ki67ratio in EGFR_high:low ≥median had worse overall survival (hazard ratio 2.41, 95% confidence interval 1.38-4.19, P=.0019). After adjusting for N stage and largest tumor dimension, patients with Ki67ratio in EGFR_high:low ≥ median had a higher risk of a disease-free failure (hazard ratio 1.85, 95% confidence interval 1.18-2.92, P=.0078). Technical validation with an independent anal cancer patient cohort was performed and shows a very similar biomarker score distribution.

CONCLUSIONS

High Ki67ratio in EGFR_high:low is associated with worse clinical outcome in this subset of patients with anal cancer treated with chemoradiation on NRG Oncology RTOG 9811. Evaluation within a clinical trial will be required to determine whether patients with these tumor characteristics may specifically benefit from an EGFR-targeted therapeutic agent.

The impact of concurrent granulocyte-macrophage colony-stimulating factor on quality of life in head and neck cancer patients: results of the randomized, placebo-controlled Radiation Therapy Oncology Group 9901 trial

PURPOSE

The Radiation Therapy Oncology Group (RTOG) conducted a randomized, placebo-controlled trial evaluating the efficacy of GM-CSF in reducing mucosal injury and symptom burden from curative radiotherapy for head and neck (H&N) cancer.

METHODS

Eligible patients with H&N cancer receiving radiation encompassing ≥50 % of the oral cavity or oropharynx received subcutaneous GM-CSF or placebo. Quality of life (QoL) was assessed using the RTOG-modified University of Washington H&N Symptom Questionnaire at baseline 4, 13, 26, and 48 weeks from radiation initiation.

RESULTS

Of 125 eligible patients, 114 were evaluable for QoL (58 GM-CSF, 56 placebo). Patient demographics, clinical characteristics, and baseline symptom scores were well balanced between the treatment arms. At the end of the acute period (13 weeks), patients in both arms reported negative change in total symptom score indicating increase in symptom burden relative to baseline (mean -18.4 GM-CSF, -20.8 placebo). There was no difference in change in total symptom score (p > 0.05) or change in mucous, pain, eating, or activity domain scores (p > 0.01) between patients in the GM-CSF and placebo arms. Analysis limited to patients treated per protocol or with an acceptable protocol deviation also found no difference in change in total symptom score (p > 0.05) or change in domain scores (p > 0.01) between treatment arms. Provider assessment of acute mucositis during treatment did not correlate with patient-reported mucous domain and total symptom scores (p > 0.05).

CONCLUSION

GM-CSF administered concurrently during head and neck radiation does not appear to significantly improve patient-reported QoL symptom burden.

RTOG 0631 phase 2/3 study of image guided stereotactic radiosurgery for localized (1-3) spine metastases: phase 2 results

PURPOSE

The phase 2 component of Radiation Therapy Oncology Group (RTOG) 0631 assessed the feasibility and safety of spine radiosurgery (SRS) for localized spine metastases in a cooperative group setting.

METHODS AND MATERIALS

Patients with 1-3 spine metastasis with a Numerical Rating Pain Scale (NRPS) score ≥5 received 16 Gy single fraction SRS. The primary endpoint was SRS feasibility: image guidance radiation therapy (IGRT) targeting accuracy ≤2 mm, target volume coverage >90% of prescription dose, maintaining spinal cord dose constraints (10 Gy to ≤10% of the cord volume from 5-6 mm above to 5-6 mm below the target or absolute spinal cord volume <0.35 cc) and other normal tissue dose constraints. A feasibility success rate <70% was considered unacceptable for continuation of the phase 3 component. Based on the 1-sample exact binomial test with α = 0.10 (1-sided), 41 patients were required. Acute toxicity was assessed using the National Cancer Institute Common Toxicity Criteria for Adverse Events, version 3.0.

RESULTS

Sixty-five institutions were credentialed with spine phantom dosimetry and IGRT compliance. Forty-six patients were accrued, and 44 were eligible. There were 4 cervical, 21 thoracic, and 19 lumbar sites. Median NRPS was 7 at presentation. Final pretreatment rapid review was approved in 100%. Accuracy of image guided SRS targeting was in compliance with the protocol in 95%. The target coverage and spinal cord dose constraint were in accordance with the protocol requirements in 100% and 97%. Overall compliance for other normal tissue constraints was per protocol in 74%. There were no cases of grade 4-5 acute treatment-related toxicity.

CONCLUSIONS

The phase 2 results demonstrate the feasibility and accurate use of SRS to treat spinal metastases, with rigorous quality control, in a cooperative group setting. The planned RTOG 0631 phase 3 component will proceed to compare pain relief and quality of life between SRS and external beam radiation therapy.

Single-fraction radiotherapy versus multifraction radiotherapy for palliation of painful vertebral bone metastases-equivalent efficacy, less toxicity, more convenient: a subset analysis of Radiation Therapy Oncology Group trial 97-14

BACKGROUND

The Radiation Therapy Oncology Group (RTOG) trial 97-14 revealed no difference between radiation delivered for painful bone metastases at a dose of 8 gray (Gy) in 1 fraction (single-fraction radiotherapy [SFRT]) and 30 Gy in 10 fractions (multifraction radiotherapy [MFRT]) in pain relief or narcotic use 3 months after randomization. SFRT for painful vertebral bone metastases (PVBM) has not been well accepted, possibly because of concerns about efficacy and toxicity. In the current study, the authors evaluated the subset of patients that was treated specifically for patients with PVBM.

METHODS

PVBM included the cervical, thoracic, and/or lumbar spine regions. Among patients with PVBM, differences in retreatment rates and in pain relief, narcotic use, and toxicity 3 months after randomization were evaluated.

RESULTS

Of 909 eligible patients, 235 (26%) had PVBM. Patients with and without PVBM differed in terms of the percentage of men (55% vs 47%, respectively; P = .03) and the proportion of patients with multiple painful sites (57% vs 38%, respectively; P < .01). Among those with PVBM, more patients who received MFRT had multiple sites treated (65% vs 49% for MFRT vs SFRT, respectively; P = .02). There were no statistically significant treatment differences in terms of pain relief (62% vs 70% for MFRT vs SFRT, respectively; P = .59) or freedom from narcotic use (24% vs 27%, respectively; P = .76) at 3 months. Significant differences in acute grade 2 through 4 toxicity (20% vs 10% for MFRT vs SFRT, respectively; P = .01) and acute grade 2 through 4 gastrointestinal toxicity (14% vs 6%, respectively; P = .01) were observed at 3 months, with lower toxicities seen in the patients treated with SFRT. Late toxicity was rare. No myelopathy was recorded. SFRT produced higher 3-year retreatment rates (5% vs 15%; P = .01).

CONCLUSIONS

Results for the subset of patients with PVBM in the RTOG 94-17 randomized controlled trial were comparable to those for the entire population. SFRT produced less acute toxicity and a higher rate of retreatment than MFRT. SFRT and MFRT resulted in comparable pain relief and narcotic use at 3 months.

Impact of sildenafil on marital and sexual adjustment in patients and their wives after radiotherapy and short-term androgen suppression for prostate cancer: analysis of RTOG 0215

PURPOSE

The Radiation Therapy Oncology Group (RTOG) 0215 investigated the efficacy of sildenafil in improving erectile dysfunction following radiotherapy and neoadjuvant/concurrent androgen deprivation therapy among prostate cancer patients and found a significant improvement on drug but only in 21% of study participants. This paper reports on a secondary aim to investigate the effect of sildenafil on overall sexual and marital adjustment among both patients and their wives.

METHODS

RTOG 0215 was a placebo-controlled, double-blind, crossover trial of sildenafil. Participation of wives was optional. Twenty-four married heterosexual couples (33% of heterosexual couples in study) completed the Sexual Adjustment Questionnaire and Locke's Marital Adjustment Test. Treatment differences in mean change scores were evaluated by paired t-tests, and the proportion of patients achieving a clinically meaningful change was evaluated using chi-square tests. Spearman's correlation coefficients were used to determine the association of adjustment between patients and wives.

RESULTS

There was no significant change in either sexual or marital adjustment for patients. For wives, there was a trend for improvement in sexual adjustment but no significant change in marital adjustment. Change in marital adjustment between patients and wives was weakly related (r(s) = 0.15, p = 0.48), and for sexual adjustment, there was a moderate, but nonsignificant relationship (r(s) = 0.40, p = 0.09).

CONCLUSIONS

Larger studies are warranted to further examine possible differences in sexual experiences and treatment needs between prostate cancer patients and their wives, as well as to assess predictors of sildenafil response.

Randomized phase III trial to evaluate radiopharmaceuticals and zoledronic acid in the palliation of osteoblastic metastases from lung, breast, and prostate cancer: Report of RTOG 0517

TPS9150

Background: Skeletal related events (SREs) diminish quality of life (QOL) as well as overall survival (OS) in patients with bone metastases, a common event in breast, lung and prostate cancer. SREs can be reduced or delayed by the use of bisphosphonates. It is postulated that the radiopharmaceuticals, Strontium-89 (Sr89) and Samarium-153 (Sm153), when added to a bisphosphonate can decrease the incidence of SREs. Methods: RTOG 0517 randomized patients with breast, lung and prostate cancer and blastic bone metastases to either Zoledronic acid (ZA) alone or ZA plus a single standard dose of either Sr89 or Sm153. No limitations were placed on additional therapy such as chemotherapy or hormonal treatment. The projected median time to SRE [pathological bone fracture, spinal cord compression, surgery to bone, or radiation to bone] for the ZA arm was 10.4 months requiring 257 SRE events to detect a 33% relative reduction for the radiopharmaceutical arm in the time to development of an SRE with 90% power. Other study objectives included quality of life, pain control, OS and toxicity. Results: 261 patients (median age 68; 62% male; 55% prostate, 35% breast, 10% lung) were accrued from July 2006 through February 2011 (4.6 patients/month). Due to a lower than expected rate of SREs in the control (ZA) arm, the study was closed early and therefore did not reach the targeted accrual. 28 (17.4%) patients in the ZA arm and 27 (16.8%) in the radiopharmaceutical arm experienced an SRE. Median time to development of an SRE in the ZA and radiopharmaceutical arms was 11.60 and 16.74 months, respectively (p=.47). Median OS in the ZA arm and radiopharmaceutical arm was 15.95 and 11.18 months, respectively (p=0.12). Cox proportional hazards regression model showed that baseline characteristics, including gender, race, ethnicity, primary disease site or number of bone metastases, had no significant impact on OS. There was no difference in QOL parameters or toxicities between the two arms. Conclusion: Patients receiving ZA only experienced a much lower SRE rate than was hypothesized. The addition of Sr89 or Sm153 did not result in a difference in SREs, OS, or QOL

Systemic therapy for advanced hepatocellular carcinoma: past, present, and future

BACKGROUND

Although approximately 80% of hepatocellular carcinoma (HCC) cases occur in developing countries, the incidence of HCC in Western countries is on the rise due to the impact of hepatitis C. Challenges in developing effective therapies include the inherent chemoresistance of HCC, the pharmacologic challenges presented by a diseased liver, the presentation of most patients at advanced stages, and the difficulty in adequately measuring radiological response. While responses to traditional chemotherapeutic agents have been documented, significant survival benefit is debatable.

METHODS

The authors review the results of published clinical trials of systemic therapy and immunotherapy that have impacted the present treatment of HCC.

RESULTS

With recent progress in the elucidation of HCC molecular pathways, targeted agents show promise. The multikinase inhibitor sorafenib has provided survival benefit in patients with advanced HCC and well-preserved liver function. Sunitinib, bevacizumab, epidermal growth factor receptor inhibitors, and mammalian target of rapamycin (mTOR) inhibitors have shown activity in small patient cohorts. Immunotherapy appears to be a promising approach that can result in the regression of bulky, invasive cancer in some patients.

CONCLUSIONS

New agents with a variety of mechanisms of activity offer promising therapeutic options for patients with advanced HCC.

Radiation Therapy as Primary and Adjuvant Treatment for Local and Regional Melanoma

Background

The role of radiation therapy as primary and adjuvant therapy for localized or locally advanced melanoma is controversial.

Methods

To develop evidence-based guidelines, PubMed was searched using the keywords melanoma AND (radiation OR radiotherapy). These references were reviewed and the relevant articles selected. The articles were then reviewed for further references. Because of the paucity of prospective or randomized trials, no attempt was made to classify the quality of the results.

Results

No phase III trials of nodal irradiation for prevention of regional recurrence are available. A phase III trial is being completed by the Tasman Radiation Oncology Group. A phase II trial has been completed by the group. Multiple retrospective series have been published. The available data appear to confirm that nodal radiation therapy is effective in preventing nodal recurrence. No dose response or fraction size response was found. According to generally accepted guidelines, radiation therapy should be offered for patients who have nodes greater than 3 cm, more than 3 involved nodes, or extracapsular extension. For radiation therapy for the treatment of metastatic disease, a phase III trial showed that 50 Gy in 2.5-Gy fractions was as effective as 32 Gy in 8-Gy fractions, with 25% complete remission and 35% partial remission. In contrast, the retrospective studies support that larger fraction sizes, at least 4 Gy, are more effective.

Conclusions

Adjuvant nodal irradiation appears to be effective for the prevention of nodal recurrence. Radiation therapy can also be effective for treatment of local disease, if surgery is not an option.

Treatment Options for Limited or Symptomatic Metastatic Melanoma

Background

Patients who develop metastatic melanoma often have limited effective treatment options. However, a select group of patients will benefit from aggressive surgery or a multidisciplinary approach, depending on the site of metastasis.

Methods

The current literature was reviewed and summarized regarding the collective recommendations for staging and treating patients with metastatic melanoma.

Results

A thorough preoperative staging includes positron-emission tomography, MRI of the brain, and CT of the chest, abdomen, and pelvis. Tumor biology ultimately determines the success of intervention. A long disease-free interval is a good indicator of potential benefit from resection of metastatic disease. If surgery is performed, no less than a complete resection will affect the overall survival of the patient. Surgery and other multimodality treatment options can be used for symptomatic palliation but will not affect survival. Chemotherapy and radiation are often used to control the symptoms of brain and bony metastases but have limited if any impact on survival.

Conclusions

A select group of patients with metastatic melanoma will benefit from aggressive surgery. Identifying which patients will benefit from treatment requires good clinical judgment and a thorough radiologic evaluation to identify the true extent of disease.

Primer on integrative oncology

At the present time, there is no obvious answer for many of these design difficulties. This problem will continue to constrain ability to determine the efficacy of integrative medical techniques for patients who have cancer. Patients, however, will continue to gravitate toward alternative treatments, especially when standard cancer treatments fail. Therefore oncologists must be aware of alternative medical agents and techniques, and be able to guide their patients, rather than simply being dismissive.

Pathophysiology and management of radiation-induced xerostomia

Radiotherapeutic treatment of head and neck cancer patients often causes long-term dysfunction involving their salivary function, swallowing capabilities, and taste. Salivary gland dysfunction from radiation therapy is often the most unpleasant side effect of treatment. This article will review current knowledge concerning the anatomy and function of glands involved with salivation, measurement of salivary gland function, surgical and pharmacologic prevention and treatment of xerostomia, and methods to administer radiation while causing the least amount of damage to salivary glands.

Assessment of quality of life and oral function of patients participating in a phase II study of radioprotection of oral and pharyngeal mucosa by the prostaglandin E(1) analog misoprostol (RTOG 96-07)

PURPOSE

The oral complications associated with radiotherapy to the head and neck are a significant dose-limiting factor. The goals of this study were to determine whether oropharyngeal rinsing and ingestion of misoprostol protect mucous membranes from the acute effects of irradiation, and to evaluate the quality-of-life (QOL) outcomes of patients receiving misoprostol. We report the results of the QOL outcomes of patients in this study.

METHODS AND MATERIALS

A total of 33 patients with resected or intact cancer of the oral cavity, oropharynx, supraglottic larynx, or hypopharynx were registered to receive postoperative radiotherapy plus misoprostol or primary radiotherapy plus misoprostol. All patients were scheduled to receive 60-70 Gy at 2 Gy/d within 6-7 weeks. QOL and function were evaluated.

RESULTS

A decrease in the QOL and function occurred in all areas covered by the questionnaire at the 6-week interval. This decrease was significant for eating, saliva, taste, and mucous. Of these significant factors, taste, saliva, and mucous consistency had not resolved by 12 weeks.

CONCLUSION

Increased understanding of the impact of treatment on QOL and symptoms will formulate the rational design of toxicity interventions and enhance the multidisciplinary care of head-and-neck patients.

Roentgen therapy for infections: an historical review

Radiation was used extensively for the treatment of all types of infections before the advent of antibiotics. Although this mode of therapy is now in disrepute, radiation therapists of that era were firm believers in the ability of radiation to cure infections. A review of the literature suggests, but certainly does not prove, that low-dose local radiation, in the range of 75 to 300 roentgens, is an effective treatment modality for a wide variety of infections. Two then-prevailing rationales held that the effect was due either to radiation damage to the immune cells, causing stimulation of the immune response, or to the increase in local inflammation with resultant increased blood flow. Modern research has been limited but provides support for both arguments. Although there are no present indications for using radiation as therapy for infectious disease, a reasonable argument can be made from the available data that radiation is effective for the treatment of localized infections. The mechanisms of low-dose radiation as a treatment for infections remain unclear. The known and probable long-term sequelae of low-dose local irradiation preclude its common use for this condition. Nevertheless, it is hoped that this review will stimulate investigations into this relatively unexplored area of radiobiology.

16,16-Dimethyl prostaglandin E2 and/or syngeneic bone marrow transplantation increase mouse survival after supra-lethal total body irradiation

We evaluated the effects of 16,16-dimethyl prostaglandin E2 (dm-PGE2), with and without syngeneic bone marrow transplantation (BMT) on the survival and hematopoietic recovery of mice given 14-20 Gy total body irradiation (TBI). Survival of mice given combined dm-PGE2 and BMT was improved significantly over that of mice given either treatment alone. The 30-day survival after 14, 15, 16 or 18 Gy TBI for combined treatment was 97, 90, 20 or 10 percent, respectively. The corresponding 30-day survival rates for mice given BMT alone were 69, 60, 7 or 0 percent, respectively. For dm-PGE2 alone, 30-day survival was 63, 20, 10 or 0 percent, respectively. Deaths in both dm-PGE2 treated groups generally occurred after day 10 whereas deaths in the BMT group occurred before day 10. All irradiated controls were dead on or before day 10; after larger doses, deaths clustered around day 5. After 20 Gy TBI, all mice in all groups were dead by day 7. Studies of white blood cell recovery 1-9 days after 14 Gy TBI showed improvement with BMT, whereas dm-PGE2 did not enhance recovery. Nucleated cells per humerus, spleen weight, and spleen iron uptake (erythropoiesis) were also improved by BMT but not dm-PGE2.

Epidemiologic aspects of toilet training

Toilet training is becoming an increasingly important child care issue as child raising becomes an institutional enterprise. This paper reviews the literature of the last 40 years, focusing on the epidemiology of the development of day and night bladder control. The studies indicate that bladder control is usually obtained between 24 months and 48 months of age. Many variations exist between studies, especially the endpoint used to indicate completion of training. Modifying the endpoint used and the related training practices could decrease the age at which children are trained.

Population frequencies of carbonic anhydrase II and esterase D in the Pittsburgh metropolitan area

Population frequencies of the genetic markers esterase D and carbonic anhydrase were determined in blacks and whites using starch gel electrophoresis. Previously published data are compared.