Clinical-dosimetric relationship between lacrimal gland dose and ocular toxicity after intensity-modulated radiotherapy for sinonasal tumours

Retinopathy, Optic Neuropathy, and Cataract in Childhood Cancer Survivors Treated With Radiation Therapy: A PENTEC Comprehensive Review

PURPOSE

Few reports describe the risks of late ocular toxicities after radiation therapy (RT) for childhood cancers despite their effect on quality of life. The Pediatric Normal Tissue Effects in the Clinic (PENTEC) ocular task force aims to quantify the radiation dose dependence of select late ocular adverse effects. Here, we report results concerning retinopathy, optic neuropathy, and cataract in childhood cancer survivors who received cranial RT.

METHODS AND MATERIALS

A systematic literature search was performed using the PubMed, MEDLINE, and Cochrane Library databases for peer-reviewed studies published from 1980 to 2021 related to childhood cancer, RT, and ocular endpoints including dry eye, keratitis/corneal injury, conjunctival injury, cataract, retinopathy, and optic neuropathy. This initial search yielded abstracts for 2947 references, 269 of which were selected as potentially having useful outcomes and RT data. Data permitting, treatment and outcome data were used to generate normal tissue complication probability models.

RESULTS

We identified sufficient RT data to generate normal tissue complication probability models for 3 endpoints: retinopathy, optic neuropathy, and cataract formation. Based on limited data, the model for development of retinopathy suggests 5% and 50% risk of toxicity at 42 and 62 Gy, respectively. The model for development of optic neuropathy suggests 5% and 50% risk of toxicity at 57 and 64 Gy, respectively. More extensive data were available to evaluate the risk of cataract, separated into self-reported versus ophthalmologist-diagnosed cataract. The models suggest 5% and 50% risk of self-reported cataract at 12 and >40 Gy, respectively, and 50% risk of ophthalmologist-diagnosed cataract at 9 Gy (>5% long-term risk at 0 Gy in patients treated with chemotherapy only).

CONCLUSIONS

Radiation dose effects in the eye are inadequately studied in the pediatric population. Based on limited published data, this PENTEC comprehensive review establishes relationships between RT dose and subsequent risks of retinopathy, optic neuropathy, and cataract formation.

International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors

BACKGROUND

Sinonasal neoplasms, whether benign and malignant, pose a significant challenge to clinicians and represent a model area for multidisciplinary collaboration in order to optimize patient care. The International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors (ICSNT) aims to summarize the best available evidence and presents 48 thematic and histopathology-based topics spanning the field.

METHODS

In accordance with prior International Consensus Statement on Allergy and Rhinology documents, ICSNT assigned each topic as an Evidence-Based Review with Recommendations, Evidence-Based Review, and Literature Review based on the level of evidence. An international group of multidisciplinary author teams were assembled for the topic reviews using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format, and completed sections underwent a thorough and iterative consensus-building process. The final document underwent rigorous synthesis and review prior to publication.

RESULTS

The ICSNT document consists of four major sections: general principles, benign neoplasms and lesions, malignant neoplasms, and quality of life and surveillance. It covers 48 conceptual and/or histopathology-based topics relevant to sinonasal neoplasms and masses. Topics with a high level of evidence provided specific recommendations, while other areas summarized the current state of evidence. A final section highlights research opportunities and future directions, contributing to advancing knowledge and community intervention.

CONCLUSION

As an embodiment of the multidisciplinary and collaborative model of care in sinonasal neoplasms and masses, ICSNT was designed as a comprehensive, international, and multidisciplinary collaborative endeavor. Its primary objective is to summarize the existing evidence in the field of sinonasal neoplasms and masses.

Proton Therapy for Advanced Juvenile Nasopharyngeal Angiofibroma

PURPOSE

To provide the first report on proton radiotherapy (PRT) in the management of advanced nasopharyngeal angiofibroma (JNA) and evaluate potential benefits compared to conformal photon therapy (XRT).

METHODS

We retrospectively reviewed 10 consecutive patients undergoing PRT for advanced JNA in a definitive or postoperative setting with a relative biological effectiveness weighted dose of 45 Gy in 25 fractions between 2012 and 2022 at the Heidelberg Ion Beam Therapy Center. Furthermore, dosimetric comparisons and risk estimations for short- and long-term radiation-induced complications between PRT plans and helical XRT plans were conducted.

RESULTS

PRT was well tolerated, with only low-grade acute toxicities (CTCAE I-II) being reported. The local control rate was 100% after a median follow-up of 27.0 (interquartile range 13.3-58.0) months. PRT resulted in considerable tumor shrinkage, leading to complete remission in five patients and bearing the potential to provide partial or complete symptom relief. Favorable dosimetric outcomes in critical brain substructures by the use of PRT translated into reduced estimated risks for neurocognitive impairment and radiation-induced CNS malignancies compared to XRT.

CONCLUSIONS

PRT is an effective treatment option for advanced JNA with minimal acute morbidity and the potential for reduced radiation-induced long-term complications.

Simulated Adaptive Radiotherapy for Shrinking Glioblastoma Resection Cavities on a Hybrid MRI-Linear Accelerator

During radiation therapy (RT) of glioblastoma, daily MRI with combination MRI-linear accelerator (MRI-Linac) systems has demonstrated significant anatomic changes, including evolving post-surgical cavity shrinkage. Cognitive function RT for brain tumors is correlated with radiation doses to healthy brain structures, especially the hippocampi. Therefore, this study investigates whether adaptive planning to the shrinking target could reduce normal brain RT dose with the goal of improving post-RT function. We evaluated 10 glioblastoma patients previously treated on a 0.35T MRI-Linac with a prescription of 60 Gy delivered in 30 fractions over six weeks without adaptation ("static plan") with concurrent temozolomide chemotherapy. Six weekly plans were created per patient. Reductions in the radiation dose to uninvolved hippocampi (maximum and mean) and brain (mean) were observed for weekly adaptive plans. The dose (Gy) to the hippocampi for static vs. weekly adaptive plans were, respectively: max 21 ± 13.7 vs. 15.2 ± 8.2 (p = 0.003) and mean 12.5 ± 6.7 vs. 8.4 ± 4.0 (p = 0.036). The mean brain dose was 20.6 ± 6.0 for static planning vs. 18.7 ± 6.8 for weekly adaptive planning (p = 0.005). Weekly adaptive re-planning has the potential to spare the brain and hippocampi from high-dose radiation, possibly reducing the neurocognitive side effects of RT for eligible patients.

Long-term follow-up and health-related quality of life among cancer survivors with stage IEA orbital-type lymphoma after external photon-beam radiotherapy: Results from a longitudinal study

We assessed the long-term outcomes and treatment-related adverse effects of patients with Stage I, "orbital-type" lymphomas that were uniformly treated with photons. All consecutive patients diagnosed with low-grade, Ann Arbor Stage IEA orbital lymphoma treated between 1999 and 2020 at our department were retrospectively reviewed. We excluded patients with exclusive conjunctival involvement, typically treated with en face electrons. In order to quantify radiotherapy related side effects we applied the CTCAE criteria, analyzed changes in visual acuity, quantified dry eye symptoms by use of the Ocular Surface Disease Index (OSDI) score and applied the EORTC QLQ-C30 questionnaire for quality of life (QoL) assessment. In total 66 eyes of 62 patients were irradiated with a median dose of 30.6 Gy. The median follow-up was 43.5 months. The predominant histological subtype were MALT lymphomas. No local failure occurred in this cohort. Of nine outfield relapses, six solely occurred in the contralateral eye. The 5- and 10- years distant progression free survival rates (PFS) were 81.4% and 63.5%. The 5- and 10-years overall survival rates were 85.1% and 71.9% without any tumor related death. Of the acute toxicities none was higher than CTCAE grade 1. The predominant late toxicities were dry eyes (21.2%) of CTCAE Grade <2 and radiation induced cataracts (19.7%). During long-term follow up the average visual acuity did not deteriorate. The global QoL was worst before treatment and improved significantly after 24 months (p = 0.007). External beam radiotherapy of "orbital-type" lymphomas with photons is an effective and gentle treatment option with excellent local control rates. From the high control rates the trend to use slightly lower total doses of 24-27 Gy with conventional fractionation is supported. As non-coplanar radiotherapy techniques improved and total doses can slightly be reduced, the current status of radiotherapy as first line therapy is provided.

A Patient Selection Approach Based on NTCP Models and DVH Parameters for Definitive Proton Therapy in Locally Advanced Sinonasal Cancer Patients

(1) Background: In this work, we aim to provide selection criteria based on normal tissue complication probability (NTCP) models and additional explanatory dose-volume histogram parameters suitable for identifying locally advanced sinonasal cancer patients with orbital invasion benefitting from proton therapy. (2) Methods: Twenty-two patients were enrolled, and two advanced radiation techniques were compared: intensity modulated proton therapy (IMPT) and photon volumetric modulated arc therapy (VMAT). Plans were optimized with a simultaneous integrated boost modality: 70 and 56 Gy(RBE) in 35 fractions were prescribed to the high risk/low risk CTV. Several endpoints were investigated, classified for their severity and used as discriminating paradigms. In particular, when NTCP models were already available, a first selection criterion based on the delta-NTCP was adopted. Additionally, an overall analysis in terms of DVH parameters was performed. Furthermore, a second selection criterion based on a weighted sum of the ΔNTCP and ΔDVH was adopted. (3) Results: Four patients out of 22 (18.2%) were suitable for IMPT due to ΔNTCP > 3% for at least one severe toxicity, 4 (18.2%) due to ΔNTCP > 20% for at least three concurrent intermediate toxicities and 16 (72.7%) due to the mixed sum of ΔNTCP and ΔDVH criterion. Since, for some cases, both criteria were contemporary fulfilled, globally 17/22 patients (77.3%) would benefit from IMPT. (4) Conclusions: For this rare clinical scenario, the use of a strategy including DVH parameters and NTCPs when comparing VMAT and IMPT is feasible. We showed that patients affected by sinonasal cancer could profit from IMPT compared to VMAT in terms of optical and central nervous system organs at risk sparing.

Management of sinonasal cancers: Survey of UK practice and literature overview

INTRODUCTION

Sinonasal malignancy is a rare and heterogenous disease, with limited evidence to guide management. This report summarises the findings of a UK survey and expert workshop discussion which took place to inform design of a proposed UK trial to assess proton beam therapy versus intensity-modulated radiation therapy.

METHOD

A multidisciplinary working group constructed an online survey to assess current approaches within the UK to surgical and non-surgical practice. Head and neck clinical oncologists, ear nose and throat (ENT) and oral-maxillofacial (OMF) surgeons were invited to participate in the 42-question survey in September 2020. The Royal College of Radiologists Consensus model was adopted in establishing categories to indicate strength of response. An expert panel conducted a virtual workshop in November 2020 to discuss areas of disagreement.

RESULTS

A survey was sent to 140 UK-based clinicians with 63 responses (45% response rate) from 30 centres, representing a broad geographical spread. Participants comprised 35 clinical oncologists (56%) and 29 surgeons (44%; 20 ENT and 9 OMF surgeons). There were variations in preferred sequence and combination of treatment modalities for locally advanced maxillary squamous cell carcinoma and sinonasal undifferentiated carcinoma. There was discordant surgical management of the orbit, dura, and neck. There was lack of consensus for radiotherapy in post-operative dose fractionation, target volume delineation, use of multiple dose levels and treatment planning approach to organs-at-risk.

CONCLUSION

There was wide variation across UK centres in the management of sinonasal carcinomas. There is need to standardise UK practice and develop an evidence base for treatment.

Precision Postoperative Radiotherapy in Sinonasal Carcinomas after Endonasal Endoscopic Surgery

Simple Summary

Sinonasal cancers are rare and heterogeneous tumors, mainly carcinomas, with essentially local evolution and a severe vital and functional prognosis. These tumors are more and more being treated in first intent by a mini-morbid endoscopic approach rather than open surgery as the cornerstone of curative treatment. Adjuvant radiotherapy remains necessary owing to non-optimal local control. This article describes the requirements of radiotherapy to ensure adequate delays, the potential of postoperative radiotherapy to increase local and distant disease control and to decrease morbidity further after mini morbid surgery and dose painting techniques, and reviews the criteria that lead to the choice of one technique over another.

Abstract

Radiotherapy plays an important role in the treatment of sinonasal cancer, mainly in the adjuvant setting after surgical resection. Many technological approaches have been described, including intensity-modulated radiotherapy, concomitant chemoradiotherapy, charged particle therapy or combined approaches. The choice is based on general criteria related to the oncological results and morbidity of each technique and their availability, as well as specific criteria related to the tumor (tumor extensions, pathology and quality of margins). The aims of this review are: (i) to provide an overview of the radiotherapy techniques available for the management of sinonasal malignant tumors and (ii) to describe the constraints and opportunities of radiotherapy owing to the recent developments of endonasal endoscopic surgery. The indication and morbidity of the different techniques will be discussed based on a critical literature review.

Supportive care for toxicities in children undergoing radiation therapy

Radiation therapy (RT) is an integral part of the management of many pediatric tumors; however, it is associated with both acute and permanent adverse events that can significantly impact a child's quality of life, lead to treatment delays, and potentially affect outcomes of cancer therapy. Prevention, early detection, and optimal management of these adverse effects will help reduce their impact on the patients' quality of life and overall well-being. Unfortunately, there has not been a coordinated effort to study the etiology, evaluate risk factors, and explore novel treatments for these conditions. Studies of supportive care for children undergoing RT are often small and uncontrolled. This review will focus on the impact of irradiation on the different organ systems and their current management. Further studies are required to improve our understanding of the contributing factors and explore novel treatment options for these adverse effects and to enable children and their families to better cope with some of the unavoidable toxicities following multimodality therapy.

Identification of patient benefit from proton beam therapy in brain tumour patients based on dosimetric and NTCP analyses

BACKGROUND

The limited availability of proton beam therapy (PBT) requires individual treatment selection strategies, such as the model-based approach. In this study, we assessed the dosimetric benefit of PBT compared to photon therapy (XRT), analysed the corresponding changes in normal tissue complication probability (NTCP) on a variety of available models, and illustrated model-based patient selection in an in-silico study for patients with brain tumours.

METHODS

For 92 patients treated at two PBT centres, volumetric modulated arc therapy treatment plans were retrospectively created for comparison with the clinically applied PBT plans. Several dosimetric parameters for the brain excluding tumour and margins, cerebellum, brain stem, frontal and temporal lobes, hippocampi, cochleae, chiasm, optic nerves, lacrimal glands, lenses, pituitary gland, and skin were compared between both modalities using Wilcoxon signed-rank tests. NTCP differences (ΔNTCP) were calculated for 11 models predicting brain necrosis, delayed recall, temporal lobe injury, hearing loss, tinnitus, blindness, ocular toxicity, cataract, endocrine dysfunction, alopecia, and erythema. A patient was assumed to be selected for PBT if ΔNTCP exceeded a threshold of 10 percentage points for at least one of the side-effects.

RESULTS

PBT substantially reduced the dose in almost all investigated OARs, especially in the low and intermediate dose ranges and for contralateral organs. In general, NTCP predictions were significantly lower for PBT compared to XRT, in particular in ipsilateral organs. Considering ΔNTCP of all models, 80 patients (87.0%) would have been selected for PBT in this in-silico study, mainly due to predictions of a model on delayed recall (51 patients).

CONCLUSION

In this study, substantial dose reductions for PBT were observed, mainly in contralateral organs. However, due to the sigmoidal dose response, NTCP was particularly reduced in ipsilateral organs. This underlines that physical dose-volume parameters alone may not be sufficient to describe the clinical relevance between different treatment techniques and highlights potential benefits of NTCP models. Further NTCP models for different modern treatment techniques are mandatory and existing models have to be externally validated in order to implement the model-based approach in clinical practice for cranial radiotherapy.

Using patient-specific bolus for pencil beam scanning proton treatment of periorbital disease

Purpose

A unique mantle cell lymphoma case with bilateral periorbital disease unresponsive to chemotherapy and with dosimetry not conducive to electron therapy was treated with pencil beam scanning (PBS) proton therapy. This patient presented treatment planning challenges due to the thin target, immediately adjacent organs at risk (OAR), and nonconformal orbital surface anatomy. Therefore, we developed a patient‐specific bolus and hypothesized that it would provide superior setup robustness, dose uniformity and dose conformity.

Materials/Methods

A blue‐wax patient‐specific bolus was generated from the patient's face contour to conform to his face and eliminate air gaps. A relative stopping power ratio (RSP) of 0.972 was measured for the blue‐wax, and the HUs were overridden accordingly in the treatment planning system (TPS). Orthogonal kV images were used for bony alignment and then to ensure positioning of the bolus through fiducial markers attached to the bolus and their contours in TPS. Daily CBCT was used to confirm the position of the bolus in relation to the patient's surface. Dosimetric characteristics were compared between (a) nonbolus, (b) conventional gel bolus and (c) patient‐specific bolus plans. An in‐house developed workflow for assessment of daily treatment dose based on CBCT images was used to evaluate inter‐fraction dose accumulation.

Results

The patient was treated to 24 cobalt gray equivalent (CGE) in 2 CGE daily fractions to the bilateral periorbital skin, constraining at least 50% of each lacrimal gland to under 20 Gy. The bolus increased proton beam range by adding 2–3 energy layers of different fields to help achieve better dose uniformity and adequate dose coverage. In contrast to the plan with conventional gel bolus, dose uniformity was significantly improved with patient‐specific bolus. The global maximum dose was reduced by 7% (from 116% to 109%). The max and mean doses were reduced by 6.0% and 7.7%, respectively, for bilateral retinas, and 3.0% and 13.9% for bilateral lacrimal glands. The max dose of the lens was reduced by 2.1%. The rigid shape, along with lightweight, and smooth fit to the patient face was well tolerated and reported as “very comfortable” by the patient. The daily position accuracy of the bolus was within 1 mm based on IGRT marker alignment. The daily dose accumulation indicates that the target coverage and OAR doses were highly consistent with the planning intention.

Conclusion

Our patient‐specific blue‐wax bolus significantly increased dose uniformity, reduced OAR doses, and maintained consistent setup accuracy compared to conventional bolus. Quality PBS proton treatment for periorbital tumors and similar challenging thin and shallow targets can be achieved using such patient‐specific bolus with robustness on both setup and dosimetry.

A multidimensional cohort study of late toxicity after intensity modulated radiotherapy for sinonasal cancer

PURPOSE

To evaluate the occurrence of late toxicity after curatively intended intensity modulated radiotherapy (IMRT) for sinonasal cancer and assess dose-response associations.

METHODS

Patients treated with IMRT in 2008-2016 were included. Cross sectional examinations of toxicity from the optic pathway, the brain, the pituitary gland and the nose were performed along with quality of life - (QoL) and dose-response analyses.

RESULTS

Twenty-seven patients were enrolled; median age was 67 years (range 47-83). Five patients (19%) had radiation-related ocular toxicity. The risk of visual acuity impairment increased with increasing dose (grade 2 odds ration (OR) 1.12, p = 0.01; grade 3 OR 1.14, p = 0.02) and dose constraint violations (grade 2, OR = 21, p < 0.01; grade 3, OR = 41, p < 0.01). Six patients (22%) exhibited evidence of radiation-related hypopituitarism, but no dose-response association was detected. Seventeen patients (63%) had impaired olfactory function. The risk of olfactory impairment increased with higher stage (OR = 3.32, p = 0.03). Three patients (11%) had structural abnormalities in irradiated areas of the brain, and impaired cognitive function was present in 17 patients (63%). Cognitive, physical, role functioning as well as fatigue and insomnia were affected the most in QOL analyses. Fifteen patients (56%) had grade 2 radiation-related impairment in at least one organ. Grade 3 toxicity was only present in patients with toxicities in >3 organs and in patients initially treated for T4 tumours. Three patients (11%) had radiation-related impaired function in all examined OARs.

CONCLUSION

Late toxicity after radiotherapy was substantial in all examined organs, with dose-response associations between visual acuity impairment and the optic nerve. The results have led to changed praxis for follow-up examinations in Denmark.

Ocular and periocular radiation toxicity in dogs treated for sinonasal tumors: A critical review

Visual impairment from radiation‐induced damage can be painful, disabling, and reduces the patient's quality of life. Ocular tissue damage can result from the proximity of ocular organs at risk to irradiated sinonasal target volumes. As toxicity depends on the radiation dose delivered to a certain volume, dose‐volume constraints for organs at risk should ideally be known during treatment planning in order to reduce toxicity. Herein, we summarize published ocular toxicity data of dogs irradiated for sinonasal tumors from 36 publications (1976‐2018). In particular, we tried to extract a dose guideline for a clinically acceptable rate of ocular toxicity. The side effects to ocular and periocular tissues were reported in 26/36 studies (72%) and graded according to scoring systems (10/26; 39%). With most scoring systems, however, toxicities of different ocular and periocular tissues are summed into one score. Further, the scores were mostly applied in retrospect and lack volume‐ and dose‐data. This incomplete information reflects the crux of the matter for radiation dose tolerance in canine ocular tissues: The published information of the last three decades does not allow formulating dose‐volume guidelines. As a start, we can only state that a mean dose of 39 Gy (given in 10 x 4.2 Gy fractions) will lead to loss of vision by one or both eyes, while mean doses of <30 Gy seem to preserve functionality. With a future goal to define tolerated doses and volumes of ocular and periocular tissues at risk, we propose the use of combined ocular toxicity scoring systems.

Clinical-dosimetric relationship between lacrimal gland dose and keratoconjunctivitis sicca in dogs with sinonasal tumors treated with radiation therapy

Background

Dogs with sinonasal tumor can develop keratoconjunctivitis sicca (KCS) after radiation therapy (RT). In humans, the incidence of xerophtalmia is associated with the mean radiation dose received by the ipsilateral lacrimal gland (LG).

Hypothesis/Objectives

The eyes receiving a higher mean LG dose are more likely to develop KCS. The aim of the study was to determine a starting threshold dose to use as dose constraint for intensity‐modulated radiation therapy (IMRT).

Animals

Dogs with nasal tumors treated with RT between August 2013 and December 2016.

Methods

Case control retrospective study of dogs with sinonasal tumor treated with 42 Gray (Gy) in 10 fractions using IMRT. Dogs were included if development of KCS after RT was documented (cases) or adequate follow‐up information with Schirmer tear test (STT) result for ≥6 months after RT was available (controls). Lacrimal glands were contoured and dose distribution was calculated using the original treatment plan to determine prescribed doses to LGs.

Results

Twenty‐five dogs were treated with RT and 5 dogs (20%) developed KCS. Fifteen dogs met the inclusion criteria including 5 unilateral KCS and 10 control dogs, resulting in 5 KCS eyes and 25 control eyes. KCS developed at a median of 111 days (84‐122) after 1st RT. The mean LG dose reached using a 4.2 Gy per fraction was 33.08 Gy (range: 23.75‐42.33) for KCS eyes and 10.33 Gy (1.8‐24.77) for control eyes (P < .001). The minimum LG mean dose for developing KCS was 23.75 Gy. No eyes that received a mean LG dose <20 Gy developed KCS versus 5/7 (71%) developed with >20 Gy.

Conclusion and Clinical Importance

Contouring and applying a dose constraint on LGs should be performed when using IMRT in dogs with sinonasal tumors to reduce the risk of KCS.

Alpha-Lipoic Acid Ameliorates Radiation-Induced Lacrimal Gland Injury through NFAT5-Dependent Signaling

Dry eye syndrome related to radiation therapy is relatively common and can severely impair a patient’s daily life. The nuclear factor of activated T cells 5(NFAT5) is well known for its osmoprotective effect under hyperosmolar conditions, and it also has immune-modulating functions. We investigated the role of NFAT5 and the protective effect of α-lipoic acid(ALA) on radiation-induced lacrimal gland (LG) injuries. Rats were assigned to control, ALA only, radiation only, and ALA administered prior to irradiation groups. The head and neck area, including the LG, was evenly irradiated with 2 Gy/minute using a photon 6-MV linear accelerator. NFAT5 expression was enhanced and localized in the LG tissue after irradiation and was related to cellular apoptosis. ALA had a protective effect on radiation-induced LG injury through the inhibition of NFAT5 expression and NFAT5-dependent signaling pathways. Functional radiation–induced damage of the LG and cornea was also restored with ALA treatment. NFAT5 expression and its dependent signaling pathways were deeply related to radiation-induced dry eye, and the condition was improved by ALA treatment. Our results suggest a potential role of NFAT5 and NF-κB in the proinflammatory effect in LGs and cornea, which offers a target for new therapies to treat dry eye syndrome.

Outcomes of orbital malignancies treated with eye-sparing surgery and adjuvant particle radiotherapy: a retrospective study

Background

To report the clinical experience of eye sparing surgery (ESS) and adjuvant carbon-ion or proton radiotherapy (CIRT or PRT) for orbital malignancies.

Methods

An analysis of the retrospective data registry from the Shanghai Proton and Heavy Ion Center for patients with orbital tumors was conducted. The 2-year local progression-free, regional recurrence-free, distant metastasis-free, progression-free, and overall survival (LPFS, RRFS, DMFS, PFS, OS) rates as well as associated prognostic indicators were analyzed. Radiotherapy-induced acute and late toxicities were summarized.

Results

Between 7/2014 to 5/2018, 22 patients with orbital malignancies of various pathologies received ESS followed by CIRT (18), PRT (1), or PRT + CIRT boost (3). With a median follow-up of 20.25 (range 3.8–38.8) months, the 2-year OS, PFS, LPFS, RRFS, and DMFS rates were 100, 57.9, 92.9, 93.3, and 72.8%, respectively. No acute severe (i.e., ≥grade 3) toxicity was observed. Two patients experienced severe visual impairment as late toxicities.

Conclusion

With few observed acute and late toxicities, particle radiotherapy following ESS provided effective local control with infrequent severe toxicities for patients with orbital malignancies.

Prospective Assessment of Patient-Reported Dry Eye Syndrome After Whole Brain Radiation

PURPOSE

Dry eye is not typically considered a toxicity of whole brain radiation therapy (WBRT). We analyzed dry eye syndrome as part of a prospective study of patient-reported outcomes after WBRT.

METHODS AND MATERIALS

Patients receiving WBRT to 25 to 40 Gy were enrolled on a study with dry mouth as the primary endpoint and dry eye syndrome as a secondary endpoint. Patients received 3-dimensional WBRT using opposed lateral fields. Per standard practice, lacrimal glands were not prospectively delineated. Patients completed the Subjective Evaluation of Symptom of Dryness (SESoD, scored 0-4, with higher scores representing worse dry eye symptoms) at baseline, immediately after WBRT (EndRT), and at 1 month (1M), 3 months, and 6 months. Patients with baseline SESoD ≥3 (moderate dry eye) were excluded. The endpoints analyzed were ≥1-point and ≥2-point increase in SESoD score at 1M. Lacrimal glands were retrospectively delineated with fused magnetic resonance imaging scans.

RESULTS

One hundred patients were enrolled, 70 were eligible for analysis, and 54 were evaluable at 1M. Median bilateral lacrimal V20Gy was 79%. At 1M, 17 patients (32%) had a ≥1-point increase in SESoD score, and 13 (24%) a ≥2-point increase. Lacrimal doses appeared to be associated with an increase in SESoD score of both ≥1 point (V10Gy: P = .042, odds ratio [OR] 1.09/%; V20Gy: P = .071, OR 1.03/%) and ≥2 points (V10Gy: P = .038, OR 1.15/%; V20Gy: P = .063, OR 1.04/%). The proportion with increase in dry eye symptoms at 1M for lacrimal V20Gy ≥79% versus <79% was 46% versus 15%, respectively, for ≥1 point SESoD increase (P = .02) and 36% versus 12%, respectively, for ≥2 point SESoD increase (P = .056).

CONCLUSIONS

Dry eye appears to be a relatively common, dose/volume-dependent acute toxicity of WBRT. Minimization of lacrimal gland dose may reduce this toxicity, and patients should be counseled regarding the existence of this potential side effect and treatments for dry eye.

Intensity-modulated radiotherapy for paranasal sinuses and base of skull tumors

Paranasal sinus and skull base tumors are rare aggressive head and neck cancers, and typically present in the locally advanced stages. As a result, achieving wide surgical resection with clear margins is a challenge for these tumors, and radiotherapy is thus usually indicated as an adjuvant modality following surgery to optimize local control. Given the integral role of radiotherapy in the management of this subgroup of head and neck tumors, the advent of intensity-modulated radiotherapy (IMRT) has led to substantial improvement of clinical outcomes for these patients. This is primarily driven by the improvement in radiation dosimetry with IMRT compared to conventional two dimensional (2D)- and 3D-techniques, in terms of ensuring dose intensity to the tumor target coupled with minimizing dose exposure to critical organs. Consequently, the evident clinical benefits of IMRT have been in reduction of normal tissue toxicities, ranging from critical neurological symptoms to less debilitating but bothersome symptoms of eye infections and radiation-induced skin changes. Another domain where IMRT has potential clinical utility is in the management of a subset of non-resectable T4 paranasal sinus and skull base tumors. For these inoperable lesions, the steep dose-gradient between tumor and normal tissue is even more advantageous, given the crucial need to maintain dose intensity to the tumor. Innovative strategies in this space also include the use of induction chemotherapy for patient selection. In this review, we summarized the data for the aforementioned topics, including specific discussions on the different histologic subtypes of paranasal sinus and skull base tumors.

Radiation dose constraints for organs at risk in neuro-oncology; the European Particle Therapy Network consensus

PURPOSE

For unbiased comparison of different radiation modalities and techniques, consensus on delineation of radiation sensitive organs at risk (OARs) and on their dose constraints is warranted. Following the publication of a digital, online atlas for OAR delineation in neuro-oncology by the same group, we assessed the brain OAR-dose constraints in a follow-up study.

METHODS

We performed a comprehensive search to identify the current papers on OAR dose constraints for normofractionated photon and particle therapy in PubMed, Ovid Medline, Cochrane Library, Embase and Web of Science. Moreover, the included articles' reference lists were cross-checked for potential studies that met the inclusion criteria. Consensus was reached among 20 radiation oncology experts in the field of neuro-oncology.

RESULTS

For the OARs published in the neuro-oncology literature, we summarized the available literature and recommended dose constraints associated with certain levels of normal tissue complication probability (NTCP) according to the recent ICRU recommendations. For those OARs with lacking or insufficient NTCP data, a proposal for effective and efficient data collection is given.

CONCLUSION

The use of the European Particle Therapy Network-consensus OAR dose constraints summarized in this article is recommended for the model-based approach comparing photon and proton beam irradiation as well as for prospective clinical trials including novel radiation techniques and/or modalities.

Head and Neck Cancer Survivorship Care Guideline: American Society of Clinical Oncology Clinical Practice Guideline Endorsement of the American Cancer Society Guideline

Purpose This guideline provides recommendations on the management of adults after head and neck cancer (HNC) treatment, focusing on surveillance and screening for recurrence or second primary cancers, assessment and management of long-term and late effects, health promotion, care coordination, and practice implications. Methods ASCO has a policy and set of procedures for endorsing clinical practice guidelines that have been developed by other professional organizations. The American Cancer Society (ACS) HNC Survivorship Care Guideline was reviewed for developmental rigor by methodologists. An ASCO Expert Panel reviewed the content and recommendations, offering modifications and/or qualifying statements when deemed necessary. Results The ASCO Expert Panel determined that the ACS HNC Survivorship Care Guideline, published in 2016, is clear, thorough, clinically practical, and helpful, despite the limited availability of high-quality evidence to support many of the recommendations. ASCO endorsed the ACS HNC Survivorship Care Guideline, adding qualifying statements aimed at promoting team-based, multispecialty, multidisciplinary, collaborative head and neck survivorship care. Recommendations The ASCO Expert Panel emphasized that caring for HNC survivors requires a team-based approach that includes primary care clinicians, oncology specialists, otolaryngologists, dentists, and other allied professionals. The HNC treatment team should educate the primary care clinicians and patients about the type(s) of treatment received, the likelihood of potential recurrence, and the potential late and long-term complications. Primary care clinicians should recognize symptoms of recurrence and coordinate a prompt evaluation. They should also be prepared to manage late effects either directly or by referral to appropriate specialists. Health promotion is critical, particularly regarding tobacco cessation and dental care. Additional information is available at www.asco.org/HNC-Survivorship-endorsement and www.asco.org/guidelineswiki .

Dry Eye Syndrome After Proton Therapy of Ocular Melanomas

PURPOSE

To investigate whether proton therapy (PT) performs safely in superotemporal melanomas, in terms of risk of dry-eye syndrome (DES).

METHODS AND MATERIALS

Tumor location, DES grade, and dose to ocular structures were analyzed in patients undergoing PT (2005-2015) with 52 Gy (prescribed dose, not accounting for biologic effectiveness correction of 1.1). Prognostic factors of DES and severe DES (sDES, grades 2-3) were determined with Cox proportional hazard models. Visual acuity deterioration and enucleation rates were compared by sDES and tumor locations.

RESULTS

Median follow-up was 44 months (interquartile range, 18-60 months). Of 853 patients (mean age, 64 years), 30.5% had temporal and 11.4% superotemporal tumors. Five-year incidence of DES and sDES was 23.0% (95% confidence interval [CI] 19.0%-27.7%) and 10.9% (95% CI 8.2%-14.4%), respectively. Multivariable analysis showed a higher risk for sDES in superotemporal (hazard ratio [HR] 5.82, 95% CI 2.72-12.45) and temporal tumors (HR 2.63, 95% CI 1.28-5.42), age ≥70 years (HR 1.90, 95% CI 1.09-3.32), distance to optic disk ≥5 mm (HR 2.71, 95% CI 1.52-4.84), ≥35% of retina receiving 12 Gy (HR 2.98, 95% CI 1.54-5.77), and eyelid rim irradiation (HR 2.68, 95% CI 1.49-4.80). The same risk factors were found for DES. Visual acuity deteriorated more in patients with sDES (0.86 ± 1.10 vs 0.64 ± 0.98 logMAR, P=.034) but not between superotemporal/temporal and other locations (P=.890). Enucleation rates were independent of sDES (P=.707) and tumor locations (P=.729).

CONCLUSIONS

Severe DES was more frequent in superotemporal/temporal melanomas. Incidence of vision deterioration and enucleation was no higher in patients with superotemporal melanoma than in patients with tumors in other locations. Tumor location should not contraindicate PT.

A Multidisciplinary Orbit-Sparing Treatment Approach That Includes Proton Therapy for Epithelial Tumors of the Orbit and Ocular Adnexa

PURPOSE

Postoperative radiation is often indicated in the treatment of malignant epithelial tumors of the orbit and ocular adnexa. We present details of radiation technique and toxicity data after orbit-sparing surgery followed by adjuvant proton radiation therapy.

METHODS AND MATERIALS

Twenty patients underwent orbit-sparing surgery followed by proton therapy for newly diagnosed malignant epithelial tumors of the lacrimal gland (n=7), lacrimal sac/nasolacrimal duct (n=10), or eyelid (n=3). Tumor characteristics, treatment details, and visual outcomes were obtained from medical records. Acute and chronic toxicity were prospectively scored using Common Terminology Criteria for Adverse Events version 4.0.

RESULTS

The median radiation dose was 60 Gy(RBE) (relative biological effectiveness; [range 50-70 Gy]); 11 patients received concurrent chemotherapy. Dose to ipsilateral anterior optic structures was reduced in 13 patients by having them gaze away from the target during treatment. At a median follow-up time of 27.1 months (range 2.6-77.2 months), no patient had experienced local recurrence; 1 had regional and 1 had distant recurrence. Three patients developed chronic grade 3 epiphora, and 3 developed grade 3 exposure keratopathy. Four patients experienced a decrease in visual acuity from baseline but maintained vision sufficient to perform all activities of daily living without difficulty. Patients with grade ≥3 chronic ocular toxicity had higher maximum dose to the ipsilateral cornea (median 46.3 Gy[RBE], range 36.6-52.7 Gy[RBE] vs median 37.4 Gy[RBE], range 9.0-47.3 Gy(RBE); P=.017).

CONCLUSIONS

Orbit-sparing surgery for epithelial tumors of the orbit and ocular adnexa followed by proton therapy successfully achieved disease control and was well tolerated. No patient required orbital exenteration or enucleation. Chronic grade 3 toxicity was associated with high maximum dose to the cornea. An eye-deviation technique can be used to limit the maximum corneal dose to <35 Gy(RBE).