Adverse effects: a Pandora's box for oncology

ACR-ARS Practice Parameter on Informed Consent Radiation Oncology

OBJECTIVES

Consent is a communication process between the patient and a health care provider, in which both parties have the opportunity to ask questions and exchange information relevant to the patient's diagnosis and treatment. The process of informed consent is designed to protect a patient's autonomy in their medical decision-making in the context of an asymmetric relationship with the health care system. A proper consent process assures a patient's individual autonomy, reduces the opportunity for abusive conduct or conflicts of interest, and raises trust levels among participants. This document was developed as an educational tool to facilitate these goals.

METHODS

This practice parameter was produced according to the process described under the heading "The Process for Developing ACR Practice Parameters and Technical Standards" on the ACR website ( https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards ) by the Committee on Practice Parameters-Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with the ARS. Committee members were charged with reviewing the prior version of the informed consent practice parameter published in 2017 and recommending additions, modifications, or deletions. The committee met through remote access and subsequently through an online exchange to facilitate the development of the revised document. Focus was given on identifying new considerations and challenges with informed consent given the evolution of the practice of radiation oncology in part driven by the COVID-19 pandemic and other external factors.

RESULTS

A review of the practice parameter published in 2017 confirmed the ongoing relevance of recommendations made at that time. In addition, the evolution of the practice of radiation oncology since the publication of the prior document resulted in the need for new topics to be addressed. These topics include remote consent either through telehealth or telephone and with the patient or their health care proxy.

CONCLUSIONS

Informed consent is an essential process in the care of radiation oncology patients. This practice parameter serves as an educational tool designed to assist practitioners in optimizing this process for the benefit of all involved parties.

Radiation Recall Pneumonitis COVID-19 Infection Induced After Adjuvant Breast Cancer Radiotherapy. A Known Phenomenon in an Unknown Pandemic Disease: A Case Report

The COVID-19 pandemic has opened several new disease scenarios, yielding novel syndromes that have never been seen before and resurrecting old inflammatory phenomena that are no longer recorded, such as radiation recall (RR) syndromes. Radiation recall syndrome is a limited field inflammatory reaction that occurs in a volume that was irradiated several months or years previously before being induced by a triggering factor. The most frequently reported phenomena are skin reactions; however, other organs could be involved, such as the lungs in radiation recall pneumonitis (RRP). It is a well-described inflammatory reaction that occurs within a pulmonary volume that was irradiated several months or years previously via radiotherapy (RT), triggered by factors such as drugs, including chemotherapy agents, immunotherapy, or vaccination. Indeed, during the COVID-19 pandemic, RRP following anti-COVID-19 vaccination or SARS-CoV2 infection was recently reported. ACE receptor-rich tissues such as lung or skin tissues were mainly involved. Herein, we present a case of RRP triggered by COVID-19 pulmonary infection in a woman who previously underwent adjuvant breast cancer radiotherapy. Although symptoms were typical, pulmonary CT findings depicted a unique distribution of ground-glass opacities (GGOs) throughout the previous radiation portals and mirror-like the radiation fields. Anamnesis and radiation plan evaluation were crucial in the diagnosis of RRP.

Informed consent in radiation oncology: is consenting easier than informing?

The patient's right to be informed has been universally recognized and reflected in the legal system of many countries. This right to correct and complete information on behalf of the patient and his admission to proceed with the recommended diagnostic or therapeutic procedure is formalized in the document commonly known as informed consent. Although the legal and bioethical considerations regarding this document have been exhaustively discussed and consensuated, its content continues to create certain doubts and uncertainties. The formal content and the manner in which the consent is obtained are the most difficult aspects. In this article, we analyze what should be included in the written informed consent, with regard to the totality of the information which the patient receives, who should inform, and how the consent should be obtained, as well as how to reflect the different aspects of the variety of radiotherapeutic procedures in the informed consent.

Radiation recall: A well recognized but neglected phenomenon

INTRODUCTION

Radiation recall is an inflammatory skin reaction at a previously irradiated field subsequent to the administration of a variety of pharmacologic agents. Although skin has been the major site of radiation recall toxicity, instances involving other organ have been reported.

MATERIALS AND METHODS

Data for this review were identified by searches of Medline and Cancerlit. The search terms "radiation", "recall", and "toxicity" were used. References identified from within retrieved articles were also used. There was no limitation on year of publication and no abstract forms were included. Only articles published in English were taken into consideration.

RESULTS

Idiosyncratic drug hypersensitivity phenomenon is a recent hypothesis which correlates best with the available facts at this moment. The phenomenon may occur days to years after radiotherapy has been completed. The majority of the drugs commonly used in cancer therapy have been involved in the radiation recall phenomenon. A mixed non-specific inflammatory infiltrate seems to be the common histopathologic criteria in previous published reports. Universally, corticosteroids or the use of non-steroidal anti-inflammatory agents, in conjunction with withdrawal of the offending agent, produce prompt improvement.

CONCLUSION

We propose to collect all future radiation recall phenomenon in a Rare Cancer Network database in order to augment our understanding of this rare reaction.

Systematic review of the effect of radiation dose on tumor control and morbidity in the treatment of prostate cancer by 3D-CRT

PURPOSE

A higher radiation dose is believed to result in a larger probability of tumor control and a higher risk of side effects. To make an evidence-based choice of dose, the relation between dose and outcome needs to be known. This study focuses on the dose-response relation for prostate cancer.

METHODS AND MATERIALS

A systematic review was carried out on the literature from 1990 to 2003. From the selected studies, the radiation dose, the associated 5-year survival, 5-year bNED (biochemical no evidence of disease), acute and late gastrointestinal (GI) and genitourinary (GU) morbidity Grade 2 or more, and sexual dysfunction were extracted. With logistic regression models, the relation between dose and outcome was described.

RESULTS

Thirty-eight studies met our criteria, describing 87 subgroups and involving up to 3000 patients per outcome measure. Between the (equivalent) dose of 70 and 80 Gy, various models estimated an increase in 5-year survival (ranging from 10% to 11%), 5-year bNED for low-risk patients (5-7%), late GI complications (12-16%), late GU complications (8-10%), and erectile dysfunction (19-24%). Only for the overall 5-year bNED, results were inconclusive (range, 0-18%).

CONCLUSIONS

The data suggest a relationship between dose and outcome measures, including survival. However, the strength of these conclusions is limited by the sometimes small number of studies, the incompleteness of the data, and above all, the correlational nature of the data. Unambiguous proof for the dose-response relationships can, therefore, only be obtained by conducting randomized trials.

Treatment with a belly-board device significantly reduces the volume of small bowel irradiated and results in low acute toxicity in adjuvant radiotherapy for gynecologic cancer: results of a prospective study

BACKGROUND AND PURPOSE

To determine whether treatment prone on a belly-board significantly reduces the volume of small bowel irradiated in women receiving adjuvant radiotherapy for gynecologic cancer, and to prospectively study acute small bowel toxicity using an accepted recording instrument.

MATERIAL AND METHODS

Thirty-two gynecologic patients underwent simulation with CT scanning supine and prone. Small bowel was delineated on every CT slice, and treatment was prone on the belly-board using 3-5 fields-typically Anterior, Right and Left Lateral, plus or minus Lateral Boosts. Median prescribed dose was 50.4 Gy and all treatments were delivered in 1.8 Gy fractions. Concomitant Cisplatin was administered in 13 patients with cervical carcinoma. Comparison of small bowel dose-volumes was made between supine and prone, with each subject acting as their own matched pair. Acute small bowel toxicity was prospectively measured using the Common Toxicity Criteria: Version 2.0.

RESULTS

Treatment prone on the belly-board significantly reduced the volume of small bowel receiving > or = 100; > or = 95; > or = 90; and > or = 80% of the prescribed dose, but not > or = 50%. This was found whether volume was defined in cubic centimeters or % of total small bowel volume. Of 29 evaluable subjects, 2 (7%) experienced 1 episode each of grade 3 diarrhoea. All other toxicity events were grade 2 or less and comprised diarrhoea (59%), abdominal pain or cramping (48%), nausea (38%), anorexia (17%), vomiting (10%). There were no Grade 4 events and no treatment days were lost due to toxicity.

CONCLUSIONS

Treatment prone on a belly-board device results in significant small bowel sparing, during adjuvant radiotherapy for gynecologic cancer. The absence of Grade 4 events or Treatment Days Lost compares favorably with the published literature.