National survey on prophylactic cranial irradiation: differences in practice patterns between medical and radiation oncologists

Limited-stage small cell lung cancer: Outcomes associated with prophylactic cranial irradiation over a 20-year period at the Princess Margaret Cancer Centre

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Prophylactic cranial irradiation (PCI) was more commonly used in younger patients.

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PCI utilization rates did not change throughout our 20-year institutional experience.

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PCI was associated with improved OS and lower brain metastasis risk, independent of MRI follow-up or era of treatment.

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For LS-SCLC patients with good thoracic response, PCI remains the standard-of-care.

Background & purpose

Prophylactic cranial irradiation (PCI) is recommended for limited-stage small-cell lung cancer (LS-SCLC) patients with good response to concurrent chemoradiation. We report our institution’s 20-year experience with this patient population and associated clinical outcomes.

Materials & methods

A retrospective cohort of consecutive LS-SCLC patients treated with curative intent chemoradiation at our institution (1997–2018) was reviewed. Overall survival (OS) was calculated using the Kaplan-Meier method, and significant covariates determined by the Cox proportional hazards model. Covariates predictive of PCI were determined using Fisher's exact test and the Mann-Whitney test. Brain failure risk (BFR) was calculated using the cumulative incidence method treating death as a competing event. Treatment cohorts (historic vs. contemporary) were stratified by the median year of diagnosis (2005).

Results

A total of 369 patients with LS-SCLC were identified, of which 278 patients were notionally PCI eligible. PCI was given to 196 patients (71%). Younger age was associated with PCI utilization (p < 0.001). PCI utilization rates did not change between the historic and contemporary treatment era (p = 0.11), whereas magnetic resonance imaging (MRI) use at baseline and follow-up became more prevalent in the contemporary era (p = <0.001). On multivariable analysis, PCI utilization was associated with improved OS (HR 1.88, 95% CI 1.32–2.69) and decreased BFR (HR 4.66, 95% CI 2.58–8.40). Patients who had MRI follow-up had a higher incidence of BFR (HR 0.35, 95% CI 0.18–0.66) in multivariable analyses.

Conclusions

For LS-SCLC patients at our institution, PCI is more frequently utilized in younger patients, and the utilization rate did not change significantly over the past 20 years. PCI was independently associated with improved OS and lower BFR. Omission of PCI in LS-SCLC patients should not be routinely practiced in the absence of further prospective data.

Physician Bias in Prophylactic Cranial Irradiation Decision Making-An Opportunity for a Patient Decision Aid

INTRODUCTION

Guidelines have recommended prophylactic cranial irradiation (PCI) for patients with limited-stage small-cell lung cancer with at least a partial response after thoracic chemoradiation. However, the survival advantage has been small and was observed in an era before magnetic resonance imaging and surveillance. Neurotoxicity also remains a concern, especially in older adults. Thus, patients have a complex value-laden decision to make. We sought to better understand the role physicians play in patient decision making and introduce a patient decision aid (PDA) to potentially facilitate these discussions.

MATERIALS AND METHODS

An e-mail survey was sent to International Association for the Study of Lung Cancer members querying their personal perspectives and professional recommendations regarding PCI for limited-stage small-cell lung cancer.

RESULTS

We received 295 responses. Most were from the United States (35%) and Europe (35%) and were radiation (45%) or medical (43%) oncologists. Of those responding, 88% and 50% reported they would recommend PCI to a 50- and 70-year-old patient, respectively. Also, 79% reported that they would wish to receive PCI if faced with this decision. The physicians who would have chosen PCI if faced with the decision were 27.6 and 12.9 times more likely to recommend PCI to a 50- and 70-year-old patient, respectively, than were physicians who would not undergo PCI themselves. Most of the respondents had positive responses to the proposed PDA.

CONCLUSION

Physician bias appears to play a role in PCI counseling, and most physicians reported that the provided PDA was better than their present method for discussing PCI and would help patients make such value-laden choices.

Cost-effectiveness of prophylactic cranial irradiation with hippocampal avoidance in limited stage small cell lung cancer

BACKGROUND AND PURPOSE

Prophylactic cranial irradiation (PCI) in limited stage small cell lung cancer (LS-SCLC) prevents brain metastases and improves survival, with the potential for neurocognitive toxicity. RTOG0933 demonstrated that hippocampal avoidance (HA) during whole brain radiotherapy preserves neurocognition. This study's objective was to evaluate the cost-effectiveness of HA-PCI in LS-SCLC through decision analysis.

MATERIALS AND METHODS

A Markov model was developed to simulate the clinical course of LS-SCLC who received HA-PCI or conventional PCI (C-PCI). A willingness-to-pay threshold of $100,000/QALY was used. Incremental cost effectiveness ratio was calculated (ICER). Sensitivity analyses were performed to determine the parameter thresholds and to assess the robustness of the model.

RESULTS

In the base case scenario, HA-PCI is more cost-effective than C-PCI, with an ICER of $47,107/QALY. HA-PCI was preferred over C-PCI provided that the risk of developing brain metastases was not increased by at least 14%, or if neurocognitive dysfunction rates were reduced by at least 40%. HA-PCI was the cost-effective strategy in 68% of tested iterations in probabilistic sensitivity analysis.

CONCLUSION

This study demonstrates that HA-PCI is more cost-effective than C-PCI in LS-SCLC. Our results support the use of HA-PCI in this patient population, should results from RTOG0933 be confirmed by the ongoing NRGCC003 trial.

Has the practice of radiation oncology for locally advanced and metastatic non-small-cell lung cancer changed in Canada?

Aim

Previous surveys have revealed wide variations in the management by radiation oncologists of non-small-cell lung cancer (nsclc) in Canada. The aim of the present study was to determine the current patterns of practice for locally advanced and metastatic nsclc among Canadian radiation oncologists.

Materials and Methods

An online survey was distributed electronically to all members of the Canadian Association of Radiation Oncologists. Those who treat lung cancer were invited to participate. The survey consisted of three scenarios focusing on areas of nsclc treatment in which the radiotherapy (rt) regimen that provides the best therapeutic ratio is unclear.

Results

Replies from 41 respondents were analyzed. For an asymptomatic patient with stage iiib nsclc unsuitable for radical treatment, 22% recommended immediate rt, and 78% recommended rt only if the patient were to become symptomatic. Those who believed that immediate rt prolongs survival were more likely to recommend it (p = 0.028). For a patient with a bulky stage iiib tumour and good performance status, 39% recommended palliative treatment, and 61% recommended radical treatment (84% concurrent vs. 16% sequential chemoradiation at 60–66 Gy in 30–33 fractions). Those who believed that chemoradiation has a greater impact on survival were more likely to recommend it (p < 0.001). For a symptomatic patient with stage iv nsclc, 54% recommended external-beam rt (ebrt) alone, 41% recommended other modalities (brachytherapy, endobronchial therapy, or chemotherapy) with or without ebrt, and 5% recommended best supportive care. A majority (76%) prescribed 20 Gy in 5 fractions for ebrt.

Conclusions

Compared with previous surveys, more radiation oncologists now offer radical treatment for locally advanced nsclc. Management of nsclc in Canada may be evidence-based, but perception by radiation oncologists of the treatment’s impact on survival also influences treatment decisions.

Donepezil and vitamin E for preventing cognitive dysfunction in small cell lung cancer patients: preliminary results and suggestions for future study designs

BACKGROUND

Up to 90% of small cell lung cancer (SCLC) patients suffer cognitive dysfunction. Since donepezil and vitamin E have been somewhat successful in treating other dementias, this study tested the hypothesis that these agents can prevent cognitive decline in SCLC patients. Because accrual was poor, this trial also offered opportunities for suggesting other study designs for future clinical trials on cognitive dysfunction in this group of patients.

METHODS

This double blind, placebo controlled trial tested oral donepezil 5 mg/day (with dose escalation to 10 mg after 1 month) and oral vitamin E 1,000 IU/day in SCLC patients after completion of all cancer therapy, including prophylactic cranial irradiation (PCI). Cognition, adverse events, and quality of life were assessed throughout the study period.

RESULTS

Only nine of 104 patients enrolled over 15 months (four donepezil and vitamin E-treated versus five placebo-exposed), and thus no definitive conclusions could be drawn. Nonetheless, the only patient who manifested a precipitous decline in cognition was taking donepezil and vitamin E. There was also a slight trend of increased gastrointestinal side effects among donepezil and vitamin E-treated patients. There were no notable differences in cognitive stability, adverse events, or quality of life between treatment arms.

CONCLUSION

These preliminary findings do not provide enthusiasm for testing donepezil and vitamin E in the manner undertaken here for preventing cognitive dysfunction in SCLC patients. Eligibility criteria and timing of trial intervention are discussed as potential impediments to successful trial completion.

Radiation treatment of lung cancer—Patterns of Practice in Canada

BACKGROUND AND PURPOSE

To assess the patterns of practice among Canadian radiation oncologists who treat lung cancers.

PATIENTS AND METHODS

A questionnaire detailing different aspects of radiation treatment of lung cancer was mailed to all radiation oncologists treating lung cancer in Canada. Seventy-two percent (74/103) of radiation oncologists who treat lung cancer from all 34 Canadian cancer centres replied to the questionnaire.

RESULTS

(a) Radiotherapy regimens in Canadian cancer centres are in accordance with several major randomised studies. There is still some variation in treatment practice that may be due to unresolved controversies or limited resources. The most frequently used prescription dose was 40Gy/15f/3w (where f stands for fractions and w stands for weeks) for small cell lung cancer (SCLC) and 60Gy/30f/6w for non-small cell lung cancer (NSCLC). If there were no resource constraints, 30% (22/74) and 20% (15/74) would prefer to use a different dose-fractionation scheme for SCLC and NSCLC, respectively; 95% (70/74) would prefer to use 3D-conformal or intensity-modulated radiotherapy. (b) Among the various modern technologies assessed by respondents, CT (computed tomography) simulator, multi-leaf collimator, on-line electronic portal imaging and PET (positron-emission tomography) scanning were rated the highest in terms of potential patient benefit. Discrepancy between demand and availability of technology was greatest for PET scanning.

CONCLUSIONS

Canadian practice in the treatment of lung cancers shows some variations although it is consistent with the trends in the literature. The lack of some modern technologies and human resources is an ongoing concern, especially the lack of PET imaging equipment.

Skin-sparing mastectomy

BACKGROUND

Skin-sparing mastectomy (SSM) is a variation of modified radical mastectomy (MRM) optimized for reconstruction. The authors attempted to determine SSM attitudes and biases within different specialties and countries throughout the world.

METHODS

The authors polled 11,485 individuals via e-mail, including members of surgical, medical, and breast oncology societies, about SSM. Respondents were directed to a survey website where data were directly entered into a database.

RESULTS

Among 1027 respondents, 19 said their knowledge was insufficient to attempt the survey. Surveys were completed by 1008 respondents (8.8%) from 52 countries, comprising 436 (43.3%) surgeons, 376 (37.3%) medical oncologists, 146 (14.5%) radiation oncologists, and 50 (5.0%) individuals from other fields. Of the respondents, 61.9% stated that SSMs are performed at their institution. However 19.1% of these believed that SSM leaves the nipple and areola intact. This perception was higher outside the U.S. (P < 0.0001). Despite knowledge by 77.8% that SSM does not have a higher local disease recurrence rate than MRM, 25.3% of these individuals did not believe the literature. This was most prevalent among radiation oncologists (48.5%), as was the belief that SSM is contraindicated in patients with ductal carcinoma in situ and invasive breast carcinoma (23.3%).

CONCLUSIONS

Despite a developing body of literature, there was variation in opinion among specialties and a lack of understanding of SSM. Many physicians were not familiar with the literature. Among those who were, skepticism was highest among radiation oncologists. Although these results were indicative of only those responding, education about SSM is needed across specialties and in other countries if the procedure is to be widely accepted.

Prophylactic cranial irradiation in small cell lung cancer

Prophylatic cranial irradiation (PCI) in patients with small cell lung cancer (SCLC) is a treatment under evaluation for about 30 years. Since the first randomized trials, it was clear that its use significantly decreased the brain metastasis rate. However, its effect on overall survival was not demonstrated. Retrospective reviews suggested that PCI could induce late neurologic damage. In recent years, two large randomized trials did not confirm this deleterious effect and even suggested a beneficial effect on survival. A recent meta-analysis including almost 1,000 randomized patients confirmed an improvement in overall survival. We discuss here the different aspects of this preventive treatment in a potentially curable disease.

Radiotherapy-related fatigue

Radiotherapy-induced fatigue is a common early and chronic side-effect of irradiation, reported in up to 80 and 30% of patients during radiation therapy and at follow-up visits, respectively. It is frequently underestimated by medical and nursing staff, only about 50% of patients discuss it with a physician and in one fourth of cases any intervention is proposed to the patient. The patients rarely expect fatigue to be a side-effect of treatment. The etiology of this common symptom, its correlates and prevalence are poorly understood. In numerous studies the level and time course of fatigue was demonstrated to depend on the site of tumor and treatment modalities. For example, psychological mechanisms have been proposed to explain fatigue in women receiving irradiation for early breast cancer, whereas decline in neuromuscular efficiency rather than psychological reasons can lead to the fatigue observed in patients undergoing radiotherapy for prostate cancer. Fatigue can affect global quality of life more than pain, sexual dysfunction and other cancer- or treatment-related symptoms. Several interventions have been tested in the management of radiotherapy-related fatigue and some randomized studies have been recently published. Although an optimal method has not yet been established, some promising results have been reported with relaxation therapy, group psychotherapy, physical exercise and sleep. Further methodologically correct studies are warranted to define better the causes, optimal prevention and management of this symptom.

Breast radiotherapy: an Australasian survey of current treatment techniques

Prior to the dissemination of evidence-based quality assurance guidelines, the Australian National Breast Cancer Centre Radiation Oncology Group conducted a process survey of breast radiotherapy treatment delivery throughout Australia. A process survey was conducted in August/September 1998. This survey comprised questions enquiring about treatment positioning, immobilization devices used, planning strategies, simulation and dose computation methods, treatment prescribing and quality assurance. The survey was sent to 123 Australian fellows of the Royal Australian and New Zealand College of Radiologists (RANZCR) and to the six directors of New Zealand radiation oncology departments. Fifty-eight questionnaires were returned of which 38 were received from individuals and 20 represented a reply from a department with a routine breast radiotherapy protocol (representing an average of 4.5 radiation oncologists per reply). The study identified great consistency between departments with respect to dose and fractionation for breast tangents. The study also identified some areas of treatment planning and delivery that varied between individuals or departments. These mainly reflected a lack of evidence in some areas of radiotherapy treatment delivery. The circulation of quality assurance guidelines will perhaps improve consistency of radiotherapy techniques in which studies have identified that technique changes improve outcome. This study identified that these areas include the taking of simulation and port films and the use of off-axis dosimetry. Further studies are required for areas of radiotherapy treatment delivery that have little evidence for or against their implementation.