Skull Involvement Research Articles

Hydrocephalus-Related Dementia in Paget Disease of the Skull.

Paget disease of bone (PDB) is a chronic skeletal disorder caused by abnormal bone remodeling. Although neurological complications are uncommon, they may arise in advanced cases, particularly with skull involvement.

Non-surgical management of severe aplasia cutis congenital accompanied by a bone defect – a case study

Background and objectives. Aplasia cutis congenita (ACC) is a rare developmental disorder that is not fully understood. It is part of a diverse group of conditions characterized by the congenital absence of THE epidermis, dermis, and occasionally subcutaneous tissues or bone, often affecting the crown of the scalp. It frequently presents as an isolated condition but can also be associated with a syndrome. Among patients, scalp involvement is common; however, large scalp defects with skull involvement are uncommon. Materials and methods. We report the case of a newborn delivered at full term by cesarean section, 3200g, in Mangalia Municipal Hospital, later transferred to the Constanta Neonatology Department, Neonatal Intensive Care department, for 3 injuries with lack of substance, both in tegument and bone, of different sizes, at the level of the vertex and the occiput. Results. Given the fragile age, a conservative management approach was chosen. The wound was meticulously cleaned daily using sterile water, and a self-adhesive absorbent dressing with hydrocolloid was applied. This dressing promoted granulation and epithelialization, adjusting dynamically to the lesion size. The newborn remained hospitalized for 35 days until the closure of the most extensive skin lesion at the vertex. Conclusions. Aplasia cutis congenita can be managed using various treatment approaches, but a consensus on the optimal strategy remains elusive. While conservative treatment has been proposed, several authors have highlighted its limitations. The choice between conservative and surgical management should be personalized, considering factors such as lesion size, location, underlying etiology, and related abnormalities.

Nonbacterial osteomyelitis of the vertebral bodies and frontal bone: A description of a rare clinical case and a review of the literature

BACKGROUND: Nonbacterial osteomyelitis is a chronic autoinflammatory skeletal disorder of unknown origin characterized by sterile bone lesions and presenting more frequently in children. Spinal manifestations are often common in nonbacterial osteomyelitis; however, cases with skull involvement, except for the mandible, are generally rare.
 CLINICAL CASE: Herein, we report the case of an 11-year-old girl presenting with multifocal thoracic vertebral and frontal bone lesions, which led to destructive sinusitis. Nonbacterial osteomyelitis was diagnosed after a bone biopsy, which showed no evidence of granuloma, malignancy, or histiocytes. The histopathological findings were nonspecific inflammatory changes. Ibandronic acid was used to treat nonbacterial osteomyelitis. Clinical signs begin to improve after the first infusion. After the fourth infusion of ibandronic acid, the inflammation was reduced and frontal bone structure and thoracic vertebrae were restored.
 DISCUSSION: Bisphosphonate therapy can be used in nonbacterial osteomyelitis when response to nonsteroidal anti-inflammatory drugs is not optimal. The efficacy of bisphosphonate therapy reaches 75%. However, bisphosphonate therapy in nonbacterial osteomyelitis has not been developed. The paper contained literature about rare cases with skull involvement and problems in bisphosphonate therapy in pediatric nonbacterial osteomyelitis.
 CONCLUSIONS: Nonbacterial osteomyelitis is a treatable condition, whose care depends on a referral to a rheumatologist.

Localized Congenital Cutis Verticis Gyrate with Skull Erosion

Localized congenital cutis verticis gyrate (CVG) is very rare and has the potential risk of skull involvement. A 23-year-old female presented with a congenital scalp mass in the occipital region. A local thickening of her left occipital scalp with ridges and furrows was observed on examination. Head CT scan showed a lytic area underneath the same area of the occipital calvarium. The mass was surgically removed due to the skull erosion and cosmetic reasons. Pathological evaluation established CVG. Surgical excision is best for localized congenital CVG with skull erosion due to cosmetic reasons. Surgical excision is rewarding to patient because she is able to style her hair now.

THU454 Paget’s Disease Of Bone As An Atypical Cause Of Headaches

Abstract Disclosure: A.N. Delgado Nieves: None. C. Gomez Hernandez: None. R. Nassar: None. P.A. Goulden: None. Background: Worsening Paget’s disease of bone (PDB) typically manifests as pelvic or spine bone pain. Headache as a primary presenting symptom of PDB is uncommon. Case Presentation: A 54-year-old female with Paget’s disease on alendronate presented at our institution with progressively worsening headaches, frontal bossing, alkaline phosphatase (ALP) of 1,668 U/L, and serum C-telopeptide of 986 pg/mL, indicating active disease. Subsequently, a bone scan confirmed active PDB, and zoledronic acid injection was administered in clinic. When re-evaluated, repeat laboratory values showed an ALP of 191 U/L, serum C-telopeptide of 511 pg/mL, PTH of 103 pg/mL, and vitamin D of 25.6 ng/mL, consistent with improved yet persistently active disease. Likewise, the patient complained of ongoing headaches, dizziness, hearing loss, and jaw pain. An X-ray of the skull showed diffuse expansile mixed Paget's disease, predominantly sclerotic, involving the calvarium with some basilar invagination noted. Subsequent whole-body bone scan showed intensely increased uptake in the skull. Audiology evaluation revealed slight to mild sensorineural hearing loss in bilateral ears. A second dose of zoledronic acid infusion was administered, and the patient’s ALP and C-telopeptide decreased to normal levels. Conclusion: We describe a case of advanced Paget’s disease presenting with persistent headaches. Clinicians should identify Paget’s disease as an atypical cause of headaches to provide appropriate treatment and prevent complications of skull involvement such as hearing loss. Presentation: Thursday, June 15, 2023

The magnetic resonance characteristics of sinonasal rhabdomyosarcoma in adults: analysis of 27 cases and comparison with pathological subtypes

BackgroundSinonasal rhabdomyosarcoma (RMS) in adults is extremely rare, and early diagnosis and treatment are crucial to improve the patient’s prognosis. The purpose of this study was to evaluate the magnetic resonance imaging (MRI) findings of sinonasal RMS in adults and analyze the correlations between the imaging features and pathological subtypes.MethodsWe reviewed 27 patients with pathologically proven RMS of the nasal cavity and paranasal sinuses, including embryonal RMS (ERMS) in 14 patients, alveolar RMS (ARMS) in seven patients, and mixed-type RMS in six patients. Conventional MRI was performed in all 27 patients, and high-resolution diffusion-weighted imaging was conducted in 25 patients. The tumor location, size, morphological features, signal intensity, texture, contrast enhancement characteristics, lymph node metastases, apparent diffusion coefficients (ADCs), and involvement of local soft tissues were independently assessed by two authors.ResultsOn MR imaging, sinonasal RMS appeared isointense on T1-weighted imaging in 21 cases (77.8%) and heterogeneously hyperintense on T2-weighted imaging in 18 patients (66.7%). After enhancement, the tumors were heterogeneously enhanced in 24 cases (88.9%). Botryoid enhancement with multiple small rings resembling bunches of grapes was found in 15 cases (55.6%). Mucosal invasion of the maxillary sinus was identified in 51.9% patients. Skull and orbit involvement were found in 55.6% and 81.5% patients, respectively. Lymph node metastasis was seen in 18 cases (66.7%). There were significant differences in botryoid enhancement (P = 0.044) and skull involvement (P = 0.044) among different histological subtypes. The mean ADC value of RMS was 0.73 ± 0.082 × 10–3 mm2/s, and there was no significant difference among different histological subtypes.ConclusionsSome characteristic MRI findings such as botryoid enhancement in the ethmoid sinus, involvement of the orbit and skull, and a lower ADC value can provide important clues for preoperative diagnosis of sinonasal RMS in adults. Further, botryoid enhancement was more common in ERMS, while skull involvement was more common in ARMS.

"Star of Bethlehem sign" in the analysis of the evolution of brain lesions during and after treatment for neuroparacoccidioidomycosis.

To describe the clinical and radiological evolution of lesions during and after treatment in patients diagnosed with neuroparacoccidioidomycosis (NPCM). This was a retrospective study of the medical records, computed tomography scans, and magnetic resonance imaging (MRI) scans of patients with NPCM treated between September 2013 and January 2022. Of 36 cases of NPCM, eight were included in the study. One patient presented only with pachymeningeal and skull involvement, and seven presented with pseudotumors in the brain. Collectively, the eight patients presented with 52 lesions, of which 46 (88.5%) were supratentorial. There were 32 lesions with a diameter ≤ 1.2 cm, of which 27 (84.4%) disappeared during the treatment. In three cases, there were lesions > 1.2 cm that showed a characteristic pattern of evolution on MRI: an eccentric gadolinium contrast-enhanced nodule, with a subsequent decreased in the size and degree of contrast enhancement of the lesions. In NPCM, supratentorial lesions seem to predominate. Lesions ≤ 1.2 cm tend to disappear completely during treatment. Lesions > 1.2 cm tend to present with a similar pattern, designated the "Star of Bethlehem sign", throughout treatment.

Skull involvement of SAPHO syndrome.

Skull involvement of SAPHO syndrome.

Central Nervous System Metastasis in Neuroblastoma: From Three Decades Clinical Experience to New Considerations in the Immunotherapy Era.

Central nervous system (CNS) metastatic spread in neuroblastoma (NB) is rare and occurs more often at relapse/progression. We report on CNS involvement in high risk (HR) NB over 25 years. For this retrospective study, we reviewed the CNS imaging of all the patients treated at Bambino Gesù Children Hospital from 1 July 1996 to 30 June 2022. A total of 128 patients with HR NB were diagnosed over 26 years. Out of 128 patients, CNS metastatic spread occurred in 6 patients: 3 patients presented a metastatic spread at diagnosis, while in 3 patients, CNS was involved at relapse. Overall, the rate of occurrence of CNS spread is 4.7% with the same distribution at diagnosis and at relapse, namely 2.3%. Interestingly, CNS spread at diagnosis was observed only before 2012, whereas CNS was observed at relapse only after 2012, in the immunotherapy era. CNS metastases presented similar imaging features at diagnosis and at relapse, with a peculiar hemorrhagic aspect and mainly hemispheric localization in patients with bone skull involvement at the time of diagnosis. The outcome is dismal, and 3 out of 6 patients died for progressive disease.

Disseminated paracoccidioidomycosis with skull and mandible involvement in a heart transplant recipient.

Disseminated paracoccidioidomycosis with skull and mandible involvement in a heart transplant recipient.

Clinical and demographic aspects of Paget disease of bone: A multicentric study from Turkey.

Paget disease of bone (PDB) is a metabolic bone disease that has been rarely reported in the Eastern countries. This study aimed to evaluate the clinical and demographic characteristics of patients with PDB followed up at endocrinology clinics in Turkey. An invitation was sent to tertiary endocrinology clinics to complete a survey on the demographic, clinical, radiological, and laboratory parameters, as well as treatment modalities of patients with PDB. This study enrolled clinically and radiologically proven 185 patients with PDB from 18 endocrinology centers based in 10 cities of Turkey. This cohort of PDB had female preponderance (women/men: 105/80) with a mean age, during diagnosis, of 57±10 years. Most of the patients (59.6%) were symptomatic at diagnosis. Bone pain and headache were the predominant clinical symptoms. Polyostotic disease was observed in 67.5% (n=125) of patients. Frequently affected bones were skull (41.6%), pelvis (53.5%), spine (41%), and femur (25.4%). Moreover, 17 patients with skull involvement had hearing loss. Mean serum alkaline phosphatase (ALP) level (552±652 IU/L; range: 280-5762 IU/L) was over the normal reference cutoff with normal serum calcium levels. Intravenous bisphosphonates (zoledronic acid, 5 mg; pamidronate, 60-90 mg) were the most used drugs (75%) for the treatment of PDB. Most of the patients (87.1%) treated with intravenous bisphosphonates responded well, with a decrease in serum ALP level (117±114 IU/L) in the 12th month of therapy. Furthermore, 16 patients relapsed after the second year of therapy; 3 patients did not respond to the initial intravenous bisphosphonate treatment. The patients with PDB followed up by endocrinology clinics of Turkey exhibited polyostotic disease with classical clinical, radiological, and biochemical features and women's predominance with good response to intravenous bisphosphonate therapy.

Imaging Spectrum of Calvarial Abnormalities.

Calvarial abnormalities are usually discovered incidentally on radiologic studies or less commonly manifest with symptoms. This narrative review describes the imaging spectrum of the abnormal calvaria. The extent, multiplicity, and other imaging features of calvarial abnormalities can be combined with the clinical information to establish a final diagnosis or at least narrow the differential considerations. Prior trauma (congenital depression, leptomeningeal cysts, posttraumatic osteolysis), surgical intervention (flap osteonecrosis and burr holes), infection, and inflammatory processes (sarcoidosis) can result in focal bone loss, which may also be seen with idiopathic disorders without (bilateral parietal thinning and Gorham disease) or with (Parry-Romberg syndrome) atrophy of the overlying soft tissues. Anatomic variants (arachnoid granulations, venous lakes, parietal foramina) and certain congenital lesions (epidermoid and dermoid cysts, atretic encephalocele, sinus pericranii, and aplasia cutis congenita) manifest as solitary lytic lesions. Other congenital entities (lacunar skull and dysplasia) display a diffuse pattern of skull involvement. Several benign and malignant primary bone tumors involve the calvaria and manifest as lytic, sclerotic, mixed lytic and sclerotic, or thinning lesions, whereas multifocal disease is mainly due to hematologic or secondary malignancies. Metabolic disorders such as rickets, hyperparathyroidism, renal osteodystrophy, acromegaly, and Paget disease involve the calvaria in a more diffuse pattern. Online supplemental material is available for this article. ©RSNA, 2021.

Schmid Type Metaphyseal Chondrodysplasia in a Large Single Genetic Lineage

Several subtypes of metaphyseal chondrodysplasia exist, of which the Schmid type is the most common. Characteristics include short limbed dwarfism, coxa vara, genu vara, and waddling gait. Skull, spine, and upper extremity involvement is minimal and often nonexistent. The primary defect involves a mutation affecting the metaphyseal portion of the growth plate, while the epiphysis is normal. A large single lineage family with metaphyseal chondrodysplasia, Schmid type (MCDS) was investigated. A genetic pedigree of 135 members of this family showed autosomal dominant inheritance between all 42 affected members. The large sample size allowed for the characterization of a broad range of features present in cases of MCDS. The majority of affected patients exhibited coxa vara with an average neck/shaft angle of 105 degrees. Despite coxa vara, premature osteoarthritis of the hip is not a feature of MCDS. Genu varum is the most prevalent knee disorder in this group, but greater than 30% of patients may exhibit genu valgum. This manuscript highlights MCDS background information, differential diagnoses, treatment options, and prognosis to aid in clinical decision-making.

Osteoblastoma in the parietal bone in elderly: rare tumor in the calvarium.

Osteoblastomas are rare bone-forming tumors that may be locally aggressive, they account for 1-3% of all primary bone tumors with the majority presenting in young adults between their second and third decades of life. This tumor predominantly affects the vertebral column and long tubular bones. Skull involvement is markedly less frequent, and particularly parietal bone involvement is extremely rare, osteoblastoma is a rare tumor older than 50 years of age.

Inion Bony Solitary Plasmocytoma: A Case Report

ackground and Importance: Plasma Cell Dyscrasias (PCD) are a heterogeneous group of diseases having a spectrum from multiple myeloma to solitary plasmacytoma, a rare subtype, which constitutes 2 to 5% of all PCD. It typically involves axial bones but the involvement of skull bone is very rare. Case Presentation: We are reporting a case of inion bony lesion with venous sinus infiltration in a 55-year-old male patient, presented with pain, imbalance in walking, and swelling in the occipital region. Brain MRI suggested an extra-axial lesion with skull involvement and venous sinus infiltration. The tumor was infiltrating into the sinus with patent torcular venous confluence. Tumor decompression followed by radiosurgery of residual lesion was considered in pre-operative surgical planning. It was diagnosed as a case of myeloma cell disease on histopathology. Postoperative myeloma work-up confirmed the absence of any systemic involvement. The patient was given a course of radiotherapy. Conclusion: One-year follow-up with repeated MRI and myeloma investigations in the 3rd month, 6th months, and 1 year did not show any finding suggestive of progression to multiple myeloma. The follow-up of brain MRI showed a complete resolution of the residual tumor.

Radiation Associated Brain Necrosis following Proton Therapy for Head and Neck Skull Base and Intracranial Tumors

To characterize the patterns and outcomes of radiation associated brain necrosis (RABN) after proton therapy (PT) for selected head and neck cancers (HNCs) with base of skull and/or intracranial involvement. Outcomes of patients with HNC treated with PT between 2010 and 2018 participating in a prospective clinical study who had one or more follow-up MRIs (≥ 6 months after treatment) and who had received at least 40 Gy(RBE) to brain were analyzed. Those who received re-irradiation were excluded. Diagnostic radiology reports and available images were reviewed for RABN defined as contrast enhanced lesions on T1- and/or edema on T2-weighted sequences. MRIs showing the RABN lesions were co-registered (rigid) with initial treatment planning CT and lesions manually contoured and volume and spatial location determined. Time to RABN was calculated from end of PT to first imaging occurrence using Kaplan-Meier method. 105 patients formed the cohort; 53 (50%) were male. Regarding disease site, 23 (22%) were nasopharynx, 19 (18%) were paranasal sinus, and 17 (16%) were peri-orbital. 62% had also received concurrent chemotherapy. Median follow-up time (from end of PT to latest MRI) was 33 months (range: 6-92). Overall, 18 patients (17.1%) developed RABN after a median latency of 24 months (range: 9-33). Actuarial RABN-free rate was 98.9%, 89.4 %, and 80.9% at 1, 2 and 3 years, respectively. All lesions were incidentally discovered on surveillance imaging and asymptomatic (grade 1) and initially observed. All lesions had a contrast enhancing component on T1 MRI. Location of lesions were temporal lobe in 12, frontal lobe in 4 and cerebellum in 2 patients. Of those with RABN, 13 (72%) had been treated for T4 or unresectable disease and 14 (78%) had intracranial tumor extension and the remainder skull base involvement. Median prescription dose to the most cranial/proximal extent of disease was 69 Gy(RBE) (range: 60-70). Median RABN lesion size (T1) was 0.2cc (range: 0.0 [punctate] to 1cc), and 12 (67%) were inside or overlapping with the high dose target volume (TV). In 5 patients (28%) RABN proved to be transient and completely resolved w/o therapy over a median time of 33 months from onset (range: 8-42), 4 (22%) show regression (2 w/ and 2 w/o medical therapy), and 3 (17%) stability (1 w/ and 2 w/o medical therapy). Three patients (17%) had progression on latest imaging, yet remain asymptomatic; each had received 70 Gy(RBE) to the most cranial TV with concurrent chemotherapy. RABN lesions following PT for skull base/intracranial disease were small, asymptomatic and regressed or completely resolved in half of the patients affected. Observation with surveillance imaging without surgical intervention is recommended for these asymptomatic radiographic lesions.

Langerhans cell histiocytosis: An enigmatic disease

Background:Langerhans cell histiocytosis (LCH) is a poorly understood disease with heterogeneous clinical presentation ranging from unifocal bony involvement to disseminated disease with life-threatening complications.Materials and Methods:The clinical profile, laboratory findings, treatment, and long-term outcome were retrieved from maintained medical records from January 2006 to January 2016 and were retrospectively analyzed. The extent of the disease was classified as per the LCH-III trial of “The Histiocyte Society.” The assessment and categorization of treatment response followed LCH III trial definitions.Results:A total of 28 children with LCH were diagnosed. The age ranged between 5 months and 9 years, with a mean of 3½ years. The M: F ratio was 3:1. Single system, unifocal and multifocal bone diseases were seen in nine (32.1%) and two (7.1%) cases, respectively. Disseminated disease without risk organ involvement was seen in six (21.1%), whereas disseminated disease with risk organ involvement was seen in 11 (39.3%) cases. The most common presentation was bony involvement (19 [67.8%]), out of which 16 (88.8%) had skull involvement. During follow-up, 17 (60.7%) were in complete remission though five (17.8%) of them relapsed, but achieved second remission. Two (7.1%) were lost to follow-up. Six (21.4%) had progressive disease of which four expired and two abandoned treatment. Two (10.7%) refused the initiation of treatment.Conclusion:A better understanding of the disease, early suspicion, and diagnosis can improve the outcome of patients with LCH.

Unusual neurosurgical emergency in Paget\u2019s disease of the skull: a case report and review of the literature

IntroductionPaget’s disease of bone is usually asymptomatic in most cases. The neurosurgeon should be familiar with the common presentation and complications. The rare presentation of this case of Paget’s disease of the skull raised our attention to report it.Case descriptionA Paget’s disease patient presented in the emergency department with a disturbed conscious level (GCS 8) without any history of trauma or seizures. CT showed severe hypertrophied left frontal, temporal, and parietal bones with midline shift. The patient underwent an emergency left decompressive craniectomy. Postoperative CT scan was done and showed frontoparietal epidural hematoma on the opposite side which was evacuated immediately. The patient started to improve and became fully conscious in few days with marked improvement of the motor power of her right side.Discussion and evaluationSevere skull involvement and impending brain herniation may occur in Paget’s disease of the skull which needs urgent decompressive surgery. Contralateral epidural hematoma after decompressive surgery may rarely occur and should be suspected in case of intraoperative brain swelling and postoperative failure of improvement. Neurosurgeons and radiologists should recognize the rare phenomenon of periosteal bone formation in the pagetic bone and its extension into surrounding tissues.ConclusionsIn our case, we faced an unusual life-threatening condition in a patient of Paget’s disease with severe skull involvement leading to rapid deterioration of consciousness and impending brain herniation. The neurosurgeon should be aware of this rare emergency condition.

Hearing in Paget's Disease of Bone

Introduction and objectivesPaget's disease of bone (PDB) may lead to hearing loss. The present study was conducted with the aim of measuring, characterising and determining the risk factors for hearing loss in a group of subjects with PDB. MethodsAn observational, transversal, case–control study was conducted, a cohort of 76 subjects diagnosed with PDB in the case group and a control group of 134 subjects were included. Clinical, demographic and audiometric data were analysed. ResultsThe comparative analysis between the subjects in the PDB group and the control group found that the case group showed higher hearing thresholds (39.51dB) compared with the control group (37.28dB) (P=.069) and presented a greater rate of conductive hearing loss (22.76%) than the control group (12.05%) (P=.0062). The study of risk factors for hearing loss found that skull involvement in bone scintigraphy, age and high blood pressure were risk factors for higher impairment in PDB. ConclusionsThe subjects with PDB showed more profound and a higher proportion of conductive hearing loss than the control group. The patients with PDB and skull involvement presented a more severe hearing loss compared with the subjects without skull involvement. Skull involvement and age were found to be risk factors for hearing loss.

Similar Local Control Rates for Patients with Meningiomas Treated with Proton Therapy vs. IMRT

To characterize the outcomes associated with fractionated proton or photon therapy for the treatment of meningiomas. We reviewed the records of 136 patients treated with RT at our institution between 2000 and 2014. Seventy-five (55%) patients received IMRT and 61 (45%) received PBT. The median age of patients was 54 years (57 years IMRT vs. 49 years PBT, P=0.003), while the majority were female (66%) and White (71%). Eighty seven (64%) had base of skull involvement with no differences between PBT and IMRT (P=0.29). Initial treatment for the majority of patients was surgical resection (n=93, 68%) with about half receiving postop RT (45%). Forty three (32%) patients received definitive RT without resection and 51 patients (38%) were treated at the time of recurrence to gross disease. RT was delivered to a median tumor size of 3.0 cm (range, 0.7-11.6) for patients with measurable disease. The median dose was 50.4 GyRBE in 28 fractions. Median follow-up time was 67 mon (range, 0-190; IMRT 91 mon vs. 54 mon, P<0.001) with a 5y OS of 79%. Sixteen (12%) patients developed a LF at a median time of 35 mon (range, 1-63), of which 10 (63%) were in-field, 3 (19%) marginal, and 3 (19%) out-of-field. There was no difference in the actuarial LF rate between PBT and IMRT when stratified by tumor grade (Grade 1: 5y LF 4% [PBT] vs. 6% [IMRT], P=0.35; Grade 2: 5y LF 43% [PBT] vs. 42% [IMRT], P=0.55; Grade 3: 3y LF 0% [PBT] vs. 25% [IMRT], P=0.48), or the median time to recurrence (31 mon [PBT] vs. 48 mon [IMRT], P=0.23) between modalities. As is apparent based on actuarial LF rates, grade 2 (n=11, 52%) and grade 3 (n=1, 13%) had a higher incidence of LF than grade 1 tumors (n=4, 4%; P<0.001). Interestingly, no patients that received definitive RT in the absence of resection (either biopsy only or no tissue acquired) recurred locally, compared with 10 patients receiving postop RT and 6 receiving RT for a gross recurrence (P<0.001). RT modality was not significantly associated with LF on multivariate analysis; the only factors associated with a higher LF rate on multivariate analysis included: grade 2 (HR 14, P<0.001, 95% CI 3.7-49.8) and grade 3 tumors (HR 184.0, P<0.001, 95% CI 11.8-2864.1), as well as larger tumor size (continuous variable, HR 1.43, P=0.003, 95% CI 1.13-1.82). Thirty seven (27%) patients had at least one late toxicity, the majority of which were grade 1-2 (n=24, 65%); there were no grade 5 toxicities. There was no difference between PBT and IMRT in the incidence of grade 1-2 late toxicities (68% vs. 58%) versus higher grade toxicities (32% vs. 42%, P=0.72). Our study demonstrates equivalency in local control for patients receiving PBT compared to IMRT with no significant difference in higher grade toxicities. Furthermore, no patients receiving definitive RT (either biopsy proven grade I or un-biopsied tumors) developed local recurrence.