Cardiotoxicity model-based patient selection for Hodgkin lymphoma proton therapy.

INTRODUCTION: Hodgkin lymphoma (HL) is a highly curable hematological malignancy. Consolidation radiation therapy techniques have made significant progresses to improve organ-at-risk sparing in order to reduce late radiation-induced toxicity. Recent technical breakthroughs notably include intensity modulated proton therapy (IMPT), which has demonstrated a major dosimetric benefit at the cardiac level for mediastinal HL patients. However, its implementation in clinical practice is still challenging, notably due to the limited access to proton therapy facilities. In this context, the purpose of this study was to estimate the benefit of IMPT for HL proton therapy for diverse cardiac adverse events and to propose a general frame for mediastinal HL patient selection strategy for IMPT based on cardiotoxicity reduction, patient clinical factors, and IMPT treatment availability. MATERIAL AND METHODS: This retrospective dosimetric study included 30 mediastinal HL patients treated with VMAT. IMPT plans were generated on the initial simulation scans. Dose to the heart, to the left ventricle and to the valves were retrieved to calculate the relative risk (RR) of ischemic heart disease (IHD), congestive heart failure (CHF) and valvular disease (VD). Composite relative risk reduction (cRRR) of late cardiotoxicity, between VMAT and IMPT, were calculated as the weighted mean of relative risk reduction for IHD, CHF and VD, calculated across a wide range of cardiovascular risk factor combinations. The proportion of mediastinal HL patients who could benefit from IMPT was estimated in European countries, based on the country population and on the number of active gantries, to propose country-specific cRRR thresholds for patient selection. RESULTS: Compared with VMAT, IMPT significantly reduced average mean doses to the heart (2.36 Gy vs 0.99 Gy, p < 0.01), to the left ventricle (0.67 Gy vs 0.03, p < 0.01) and to the valves (1.29 Gy vs. 0.06, p < 0.01). For a HL patient without cardiovascular risk factor other than anthracycline-based chemotherapy, the relative risks of late cardiovascular complications were significantly lower after IMPT compared with VMAT for ischemic heart disease (1.07 vs 1.17, p < 0.01), for congestive heart failure (2.84 vs. 3.00, p < 0.01), and for valvular disease (1.01 vs. 1.06, p < 0.01). The median cRRR of cardiovascular adverse events with IMPT was 4.8%, ranging between 0.1% and 30.5%, depending on the extent of radiation fields and on the considered cardiovascular risk factors. The estimated proportion of HL patients currently treatable with IMPT in European countries with proton therapy facilities ranged between 8.0% and 100% depending on the country, corresponding to cRRR thresholds ranging from 24.0% to 0.0%. CONCLUSION: While a statistically significant clinical benefit is theoretically expected for ischemic heart disease, cardiac heart failure and valvular disease for mediastinal HL patients with IMPT, the overall cardiotoxicity risk reduction is notable only for a minority of patients. In the context of limited IMPT availability, this study proposed a general model-based selection approach for mediastinal HL patient based on calculated cardiotoxicity reduction, taking into consideration patient clinical characteristics and IMPT facility availability.

High-dose proton therapy and tomotherapy for the treatment of sacral chordoma: a retrospective monocentric study.

OBJECTIVE: Radiation therapy (RT) is used for the treatment of sacral chordoma, in combination with surgery or alone for unresected tumours, to improve local control (LC) and potentially overall survival (OS). The purpose of the present study was to evaluate efficacy and toxicity of proton therapy (PT), and/or intensity modulated radiation therapy (IMRT), particularly Tomotherapy, for sacral chordoma treatment. Material: Between November 2005 and June 2018, 41 consecutive patients who were not included in clinical trials, received sacral chordoma radiation treatment in Institut Curie with Tomotherapy alone in 13 patients, and combined PT and Tomotherapy boost (Proton - Tomo) in 28 patients. RT was delivered as the exclusive local treatment in 11 patients, and as a post-operative complementary treatment in 30 patients. RESULTS: After a median follow-up of 46 months (range, 0-125 months), eight local relapses were observed, and seven patients developed distant metastasis (particularly bone and lung). The 2- and 5- year local relapse rates were 11.4% CI (0.65-22.2%) and 29% (10.5-47.4%), respectively. Over the follow-up period, ten patients died (24.4%). The estimated 2- and 5-year OS rates were 91.4% CI (82.5-100%) and 74.5% (59.4-93.5%), respectively. Fibrosis, cauda equina syndrome, and pain were the most common late toxicities. The comparison between Tomotherapy alone and Proton - Tomo revealed that acute and late cystitis were significantly more frequent in the Tomotherapy group: SHR = 0.12 IC95% (0.01-0.90 [p = .04]), as well as late proctitis. A dosimetric comparison confirmed the interest of PT to spare rectum and bladder in this context. CONCLUSION: RT remains essential to improve local control in sacral chordoma. The combination of proton and photon seems to improve organ at risk sparing, resulting in a decreased rate of reported late toxicities.

Craniofacial second primary tumors in patients with germline retinoblastoma previously treated with external beam radiotherapy: A retrospective institutional analysis.

BACKGROUND: The long-term survival of germline retinoblastoma patients is decreased due to the risk of second primary tumors (SPTs) that occur years after the diagnosis of retinoblastoma. This risk is related to genetic predisposition and other factors, such as the treatment of retinoblastoma by external beam radiotherapy (EBRT). PROCEDURE: We studied the incidence, risk factors, and prognosis of specific craniofacial SPTs developed within the margins of radiation field in a cohort of 209 patients with germline retinoblastoma treated with EBRT at our institution between 1977 and 2010. Clinical characteristics, survival, incidence, and histology of craniofacial SPTs were recorded. RESULTS: Fifty-three of the 209 patients developed 60 distinct craniofacial SPTs in irradiated field with a median time from EBRT of 16.9 years (4-35) and a median follow-up of 24.8 years (5.3-40). Osteosarcoma (33.3%) and undifferentiated sarcoma (23.3%) were the more prevalent histological entities. Benign tumors (16.7%) also occurred. The cumulative incidence of craniofacial SPTs reached 32.6% at 35 years after EBRT, and the median survival after diagnosis was five years. In our series, irradiation under 12 months of age, bilateral EBRT, or previous treatment of retinoblastoma with chemotherapy did not significantly increase the risk of craniofacial SPTs. CONCLUSIONS: This work presents a strong argument to avoid EBRT in the management of retinoblastoma and emphasizes the high risk and poor prognosis of specific craniofacial SPTs. This study also points to the question of the need and benefits of special programs for early detection of craniofacial SPTs in survivors of irradiated germline retinoblastoma.

Management of advanced uni- or bilateral retinoblastoma with macroscopic optic nerve invasion.

BACKGROUND: Retinoblastoma with macroscopic optic nerve (ON) invasion depicted by imaging at diagnosis remains a major problem and carries a poor prognosis. We sought to describe the treatment and outcome of these high-risk patients. METHODS: Retrospective mono-institutional clinical, radiological, and histological review of patients with uni- or bilateral retinoblastoma with obvious ON invasion, defined by radiological optic nerve enlargement (RONE) depicted by computed tomography scan or magnetic resonance imaging (MRI), was performed. RESULTS: Between 1997 and 2014, among the 936 patients with retinoblastoma treated at Institut Curie, 11 had detectable RONE. Retinoblastoma was unilateral in 10 and bilateral in one. Median age at diagnosis was 28 months (range, 11-96). ON enlargement extended to the orbital portion in three patients, to the optic canal in five, to the prechiasmatic portion in two, and to the optic chiasm in one. Nine patients received neoadjuvant chemotherapy and partial response was obtained in all. Enucleation was performed in 10/11 patients-by an anterior approach in three and by anterior and subfrontal approaches in seven. Three patients had a positive ON resection margin (2/3 after primary enucleation). All enucleated patients received adjuvant treatment (conventional chemotherapy: 10, high-dose chemotherapy: seven, radiotherapy: five). Leptomeningeal progression occurred in four patients. Seven are in first complete remission (median follow up: 8 years [3.5-19.4]). CONCLUSION: Neoadjuvant chemotherapy and microscopic complete resection have a pivotal role in the management of retinoblastoma with RONE. MRI is recommended for initial and pre-operative accurate staging. Surgery should be performed by neurosurgeons in case of posterior nerve invasion. Radiotherapy is required in case of incomplete resection.

TREATMENT OF EXUDATIVE CIRCUMSCRIBED CHOROIDAL HEMANGIOMA: Efficacy of Fractionated Proton Therapy (20 Gray Relative Biological Effectiveness in 8 Fractions).

PURPOSE: To evaluate treatment of circumscribed choroidal hemangioma by hyperfractionated proton beam therapy protocol (20 gray relative biological effectiveness in 8 fractions) on tumor control, attachment of retina and visual function. METHODS: Retrospective review of patients treated between January 2010 and April 2015 with at least 6 months of follow-up. RESULTS: Forty-three patients with exudative and symptomatic circumscribed choroidal hemangioma were included. Before treatment, 41 (95%) presented an exudative retinal detachment, median visual acuity was 20/63 and median tumor thickness was 3.3 mm. Mean follow-up was 26 months (7-62). At last follow-up, all patients presented regression of ultrasound tumor thickness and 23/43 (53.5%) a totally flat scar. The mean time to achieve a flat scar was 20 months. Retina was reattached in all patients except one with 9 months of follow-up. Visual acuity was improved or stabilized in 37 patients (86%) and final median visual acuity was 20/25. No patient presented radiation maculopathy or papillopathy. CONCLUSION: Proton beam therapy with a dose of 20 gray relative biological effectiveness delivered in 8 fractions provides excellent anatomical and functional results and are comparable with those obtained with the same dose delivered in 4 fractions. Longer follow-up is required to determine the long-term radiation sequelae.

Intravitreal bevacizumab for neovascular glaucoma in uveal melanoma treated by proton beam therapy.

BACKGROUND: To evaluate the efficacy of bevacizumab on reduction of the enucleation rate and control of intraocular pressure (IOP) in neovascular glaucoma (NVG)-complicating proton beam therapy for UM and to identify the determinants of the efficacy of bevacizumab. METHODS: Retrospective comparative study of patients with rubeosis following proton therapy for uveal melanoma. Patients were divided into two groups: a bevacizumab group and a control group which comprised two subgroups: panretinal photocoagulation (PRP)/cryotherapy and observation subgroups. Bevacizumab was administered by three intravitreal injections at 1-month intervals. A second series of injections was administered when necessary. Data concerning IOP and the secondary enucleation rate were collected and compared between the two groups. Univariate and multivariate analyses were performed to determine predictive factors of response to bevacizumab. RESULTS: A total of 169 patients who developed rubeosis following proton therapy between 2006 and 2016 were included: 44 patients in the bevacizumab group and 125 in the control group (38 in the PRP/cryotherapy subgroup and 87 in the observation subgroup). The two groups presented the same baseline characteristics apart from hypertension, retro-equatorial site, and proximity of the optic disk, which were more frequent in the control group, while initial retinal detachment and larger tumor volume were more frequent in the bevacizumab group. After a mean follow-up of 31 months, IOP was less than 21 mmHg in 54.54% of patients after IVB versus 72.7% before treatment (p = 0.06). Statistical analysis did not reveal any statistically significant reduction of the enucleation rate in the bevacizumab group compared to the observational group, whereas the PRP/cryotherapy group showed better eye retention rate (p = 0.15). No enucleation was performed when IOP was < 21 mmHg before IVB. Multivariate analysis identified initial IOP < 21 mmHg and UM situated away from the macula as predictive factors of good response to bevacizumab. CONCLUSION: Despite the improvement of IOP level, intravitreal bevacizumab (IVB) did not reduce the overall enucleation rate in NVG following proton beam therapy. Nevertheless, this treatment was effective in the early phases of NVG or as preventive treatment. PRP remains a valid treatment for NVG.

Retinal cavernous haemangioma treated by proton beam therapy.

As one of intraocular tumours, retinal cavernous haemangioma is a benign vascular lesion that is mostly unilateral. Very few cases about cavernous haemangioma treatment are reported, and there is currently no consensus on the most effective treatment. This clinical case reports on a 40-year-old male, presenting a peripheral retinal cavernous haemangioma, complicated with a repetitive vitreous haemorrhage causing bad vision. Several therapeutic methods were unsuccessfully attempted to stop haemorrhagic recurrences. Thanks to proton beam irradiation, a good collapse of aneurismal dilatations was obtained, with no recurrence of bleeding. This case study confirms that proton beam therapy is a good alternative in treating cavernous haemangiomas, leading to a total tumour regression without complications.

The biological and prognostic significance of angiotropism in uveal melanoma.

Angiotropism is a marker of extravascular migration of melanoma cells along vascular and other structures and a prognostic factor in cutaneous melanoma. Because of this biological and prognostic importance in cutaneous melanoma, angiotropism was studied in uveal melanoma (UM). This retrospective study performed at a single ocular oncology referral center included 89 patients from the study period 2006-2008. All patients were diagnosed with UM from the choroid and/or ciliary body. All patients underwent enucleation for prognostic purposes and definitive therapy. Clinical, histopathological, and molecular variables included patient age, gender, extraocular extension, tumor location (ciliary body or not), optic nerve invasion, angiotropism, neurotropism, melanoma cell type, BAP1 mutation, and monosomy 3. Angiotropism was defined as melanoma cells arrayed along the abluminal vascular surfaces without intravasation in the sclera and/or episcleral tissue. The study included 51 women (57.3%) and 38 men with mean and median age: 63 years (range: 25-92). Mean follow-up was 4.4 years (range: 0.2 to 11). Fifty-three (59.6%) patients developed metastases and 48 (53.9%) were dead from metastases at last follow-up. Other principal variables recorded were angiotropism in 43.8%, extraocular extension in 7.9%, epithelioid/mixed cell type in 73.1%, BAP1 mutation in 41.3%, and monosomy 3 in 53.6% of cases. On multivariate analysis, extraocular extension, angiotropism, and monosomy 3 were predictive of metastasis, whereas tumor diameter, epithelioid cell type, angiotropism, and monosomy 3 were predictive of death. Chi-square test confirmed an association between angiotropism and metastasis and death but none with BAP1 mutation and monosomy 3. In conclusion, angiotropism and monosomy 3 were independent prognostic factors for both metastases and death in UM. However, irrespective of any prognostic value, the true importance of angiotropism is its biological significance as a marker of an alternative metastatic pathway.Laboratory Investigation advance online publication, 27 February 2017; doi:10.1038/labinvest.2017.16.

Chordoma in children: Case-report and review of literature.

We report an exceptional case of a very late local failure in a 9-year-old boy presenting with a chordoma of the cranio-cervical junction. The child was initially treated with a combination of surgical resection followed by high dose photon-proton radiation therapy. This aggressive therapy allowed a 9-year remission with minimal side-effects. Unfortunately, he subsequently presented with a local failure managed with a second full-dose course of protons. The child died one year later from local bleeding of unclear etiology.

Reprint of "Chordoma in children: Case-report and review of literature".

We report an exceptional case of a very late local failure in a 9-year-old boy presenting with a chordoma of the cranio-cervical junction. The child was initially treated with a combination of surgical resection followed by high dose photon-proton radiation therapy. This aggressive therapy allowed a 9-year remission with minimal side-effects. Unfortunately, he subsequently presented with a local failure managed with a second full-dose course of protons. The child died one year later from local bleeding of unclear etiology.

Primary ophthalmic natural killer/T-cell lymphoma: A population-based study.

BACKGROUND: Ophthalmic lymphomas, a subgroup of extra-nodal lymphomas, have seen an increase in incidence in recent decades. Of these, the NK/T-cell lymphoma (NKTL) subtype is particularly aggressive. Though prevalent mostly in Asian patients, data on ophthalmic NKTL is still limited, especially in the western population. This study aimed to provide an additional analysis of primary ophthalmic NKTL using the Surveillance, Epidemiology, and End Results (SEER) database. METHODS: A retrospective analysis was performed on the SEER database covering records from 2000 to 2020. Patients diagnosed with extranodal NKTL originating primarily from an ophthalmic structure were identified. RESULTS: Out of 4540 ophthalmic lymphomas registered in the SEER database between 2000 and 2020, 9 cases (0.2%) corresponded to ophthalmic NKTL, occurring in patients with a median age of 67 years. The majority of these patients underwent chemotherapy (88.8%) and radiotherapy (66.6%). The 6-month overall survival (OS) and cancer-specific survival (CSS) were both at 50.8%, dropping significantly at the 2-year follow-up. CONCLUSION: Primary orbital NKTL has a notably severe prognosis. An early diagnosis is important due to the aggressive nature of NKTL.

Intraocular Invasion by Conjunctival Squamous Cell Carcinoma: Clinical Presentation, Histopathological Findings, and Outcome.

Introduction: Intraocular localization of conjunctival squamous cell carcinoma (SCC) is due to scleral or corneal invasion. Herein, we describe the clinical and histopathological findings in four cases of SCC complicated by intraocular invasion, and we review cases reported in the literature and their management. We retrospectively collected and analyzed clinical characteristics, histopathology, management, and follow-up data from 4 patients with conjunctival SCC complicated by intraocular invasion. We reviewed the literature and summarized cases of intraocular invasion by conjunctival SCC reported over the last 30 years. Case Presentations: Two patients presented with intraocular invasion by conjunctival SCC at diagnosis. The two others developed intraocular invasion as recurrence of conjunctival SCC, previously treated with excisional biopsy and adjuvant radiotherapy. All 4 cases had a previous history of conjunctival surgery, but no history of intraocular surgery. Three patients were managed with modified enucleation, including one that required adjuvant orbital radiotherapy. One patient required orbital exenteration. Histopathology analysis showed a well-differentiated conjunctival SCC in all cases. None developed distant localization after at least 2.5-year follow-up. Discussion/Conclusion: Intraocular invasion is a rare complication of conjunctival SCC. Appropriate treatment in a tertiary center and long-term follow-up are highly recommended.

Curative high-dose reirradiation for patients with recurrent head and neck adenoid cystic carcinomas: outcomes and analysis of patterns of failure.

BACKGROUND: To investigate the outcomes of patients who underwent curative reirradiation (reRT), with intensity-modulated radiation therapy (IMRT) or proton therapy (PT) for unresectable recurrent or second primary head and neck adenoid cystic carcinoma (HNACC). METHODS: Ten patients, mostly KPS 90%, were reirradiated (3/10 with IMRT and 7/10 with PT) at a median maximum dose to the CTV of 64.2 Gy from July 2011 to November 2021. Locations at the time of reRT were mainly the sinus (4/10) and the salivary glands (including the parotid and submandibular gland, 3/10). CTCAEv5 was used to assess acute and late toxicities. Follow-up was the time between the end of reRT and the date of last news. RESULTS: The median time between the two irradiations was 53.5 months (IQR: 18-84). After a median follow-up of 26 months (range, 12.5-51.8 months), six patients had developed a locoregional recurrence (LR), of which four occurred within the previously irradiated volume. Two and three-year locoregional failure-free survival (LFFS) and overall survival (OS) were 55.6% [95%CI: 31-99.7%], and 41% [18.5-94%] and 66.7% [42-100%] and 44.4% [21.4-92.3%], respectively. LFFS and OS were significantly better in the subgroup of sinus tumors (p = .013) and the subgroup of patients re-irradiated more than two years after the first course of irradiation (p = .01). Seven patients had impairments before the start of reRT, including hearing impairment (3/10) and facial nerve impairment (3/10). The most severe late toxicities were brain necrosis (2/10), osteoradionecrosis (1/10) and vision decreased (1/10). CONCLUSION: Curative reRT for HNACC is possible for selected cases, but the LR rate in the irradiated field and the risk of severe toxicity remain high. Improved selection criteria and more carefully defined target volumes may improve outcome in these patients. A further study including larger cohort of patients would be useful to confirm these results.

Choroidal melanoma: does endoresection prevent neovascular glaucoma in patient treated with proton beam irradiation?

PURPOSE: To evaluate the efficacy of endoresection after proton beam radiotherapy to prevent neovascular glaucoma (NVG) in patients treated for choroidal melanoma. METHODS: From a series of 4,867 patients treated for choroidal melanoma were prospectively recorded in the database (Macro Infermed 3.075). One hundred and seventy-one patients presenting a tumor diameter >10 mm and thickness >5 mm treated with proton beam (PB) radiotherapy were selected. One group of 63 patients was treated with PB therapy followed by endoresection (PE) of the scar. This group was compared with 2 historical matched controlled groups: 57 patients treated with PB therapy alone (P) and 51 patients treated with PB therapy followed by transpupillary thermotherapy of the scar (PTTT). Main outcome measures are as follows: age, gender, tumor diameter, tumor thickness, pre- and posttreatment visual acuity, NVG rate, secondary enucleation rate, and 5-year survival. Statistical analysis was performed using R version 2.5.1 software. RESULTS: Correlations between the 3 groups were P = 0.29 for age, P = 4.7×10 for tumor diameter, and P = 6.44×10 for tumor thickness. Comparison between the 3 groups showed that 2-year survival without secondary enucleation was 96.2% for PE, 88.8% for P, and 98% for PTTT (P = 0.203) (95% confidence interval). Two-year survival without NVG (95% confidence interval) was 92.7% (85.1-1.00) for PE, 54.6% for P, and 62.1% for PTTT (P = 0.0001). The difference between the endoresection (PE) group and the PB radiotherapy (P) and PB radiotherapy + TTT (PTTT) groups in terms of reduction of the NVG rate was statistically significant. Relative risk of developing NVG was calculated with the P group as reference, relative risk = 1. The relative risk of the PTTT group was 0.79 (20% reduction of the risk), and the relative risk of the PE group was 0.18 (82% reduction of the risk of developing NVG). CONCLUSION: This study shows that endoresection of the necrotic scar after PB radiotherapy reduces the risk of NVG and secondary enucleation for selected choroidal melanoma patients.

Tolerance and Oncological Outcomes of In-Field Reirradiation for Locally Recurrent Breast Cancer: A Long-Term Single-Center Experience.

BACKGROUND: The management of cancer relapse in previously irradiated tissues is a challenging therapeutic issue. The aim of this work was to report our experience with breast reirradiation for locoregionally recurrent breast cancer. METHODS: All patients who underwent breast or chest wall in-field reirradiation at the Institut Curie, Paris, France, between 2003 and 2019, were identified. Efficacy outcomes and physician-reported toxicities were retrospectively assessed. RESULTS: A total of 21,372 patients underwent breast irradiation in our institution. Of these, 28 received a second course of radiotherapy to the homolateral breast/chest wall. A total of 18 (64%) patients were treated with a curative intent, and 10 (36%) were treated for palliative purposes. Only one acute and one late grade 3 adverse events were reported. One patient with major cardiovascular risk factors died of myocardial infarction 13 months after left breast reirradiation. The 2-year LRFS, OS, DSS, PFS and MFS were 59%, 79%, 82%, 46% and 75%, respectively, in the whole cohort. The 2-year LRFS (72% vs. 31%, p = 0.02), OS (94% vs. 50%, p < 0.01), DSS (94% vs. 56%, p < 0.01) and PFS (61% vs. 20%, p = 0.02) differed significantly between patients treated with curative or palliative intent but not the MFS (78% vs. 69%, p = 0.77). Among the patients, eight (29%) remained relapse-free 5 years after reirradiation. CONCLUSION: Breast/chest wall reirradiation appears to be feasible with good disease control, especially in patients treated with a curative intent, and presents acceptable toxicity rates.

Proton therapy for adult craniopharyngioma: Experience of a single institution in 91 consecutive patients.

BACKGROUND: Craniopharyngioma (CP) in adults is a rare benign tumor associated with many morbidities, with limited contemporary studies to define treatment, and follow-up guidelines. METHODS: A single-center retrospective study was conducted on patients aged ≥ 18 years from 2006-2018 with CP and who were treated with proton therapy (PT). Late toxicity was defined as a minimum of 18 months from diagnosis. Overall survival (OS), local recurrence-free survival (LRFS), and toxicity were characterized using Kaplan-Meier and Cox regression analyses. RESULTS: Ninety-one patients met the criteria, with a median age of 37 years (range 18-82 years). PT was conducted after tumor resection in 88 patients (97%), in 64 patients (70.3%) as an adjuvant strategy and in 27 (29.7%) after recurrent disease. Three patients received exclusive PT. A median MRI follow-up of 39 months revealed 35.2% complete response, 49.5% partial response, and 9.9% stable disease. Five patients developed local recurrence (LR). The pattern of failure study showed that these five LR were within the GTV volume. The 5-year LRFS was 92.0% [CI 95% 84.90-99.60]. All the patients were alive at the end of the follow-up. Patients requiring treatment adaptation during PT tend to have a higher risk of LR (P = .084). Endocrinopathy was the most frequent grade ≥ 2 late toxicity. Among patients who were symptom-free before the start of treatment, none developed hearing toxicity but four (9.8%) developed visual disorders and 10 (11.3%) symptomatic memory impairment. Patients with large tumors had a higher risk of developing symptomatic memory impairment (P = .029). CONCLUSION: Adults with CP treated with PT have favorable survival outcomes, with acceptable late toxicity. Prospective quality-of-life and neurocognitive studies are needed to define late adverse effects better.

Proton therapy and/or helical tomotherapy for locally advanced sinonasal skull base adenoid cystic carcinoma: Focus on experience of the Institut Curie and review of literature.

BACKGROUND: Sinonasal adenoid cystic carcinomas (SNACC) have high propensity for skull base (SB) infiltration. Unresectability or incomplete surgical resection in such cases make radiotherapy treatment paramount. Curative dose escalation is challenging because of adjacent organs at risk, especially in locally advanced cases. METHODS: Eighteen patients that had locally advanced SB SNACC with unresectable or incomplete surgical resection treated by proton therapy and/or helical tomotherapy at Institut Curie between 3/2010 and 8/2020 were retrospectively included. RESULTS: After median follow-up of 52 months, 5-year OS, LRRFS, DMFS, DFS rates were, respectively, 47% (95%CI: 26-83), 50% (95%CI: 36-88), 39% (95%CI: 26-81), 33% (95%CI: 22-73). One patient had grade 4 late optic nerve disorder. Eight patients had grade 3 late toxicity including mainly hearing impairments. CONCLUSION: Proton therapy and helical tomotherapy are effective and safe methods for curative dose escalation of locally advanced SB SNACC, which are a poor prognosis subgroup. Available literature suggests carbon-ion therapy could be an efficient alternative.