Risk Factors Associated with Development of Peritumoral Edema Following Stereotactic Radiosurgery and Radiotherapy for Intracranial Meningioma

PURPOSE/OBJECTIVE(S)

Peritumoral edema (PTE) is a potential adverse effect following radiotherapy for intracranial meningioma. The purpose of this study is to identify which baseline factors may increase risk for PTE.

MATERIALS/METHODS

A retrospective chart review was conducted of 431 patients who underwent primary radiotherapy to 480 radiographically-defined intracranial meningiomas between January 2008 and December 2021 within an integrated health care system. Patients with prior surgical management were excluded. Patients were treated with frameless LINAC-based image-guided single fraction stereotactic radiosurgery (SRS) (32.9%), 5 fraction SRS (FSRS) (30.8%), or fractionated stereotactic radiotherapy (FSRT) (36.3%). Pre- and post-radiotherapy MRI studies were reviewed to evaluate for PTE following treatment. An event was defined as new or worsening PTE compared to pre-radiotherapy imaging or development of new symptoms post-radiotherapy. Univariate and stepwise logistics regression analyses were performed to compare the risk of PTE between groups.

RESULTS

Median follow-up was 85.8 months (IQR: 49.4-125.4). Median patient age was 66 years (IQR: 56-73). Patients treated with SRS (median age: 61 years) were younger than those treated with FSRS/FSRT (median age: 68 years) (p<0.001). Lesions treated with SRS (median volume: 1.33cc) were smaller than those treated with FSRS/FSRT (median volume: 6.36cc) (p<0.001). For all-comers, 68 (14.2%) lesions developed any PTE, and 27 (5.6%) developed symptomatic PTE (SPTE). Of these, 4 patients developed symptoms post-treatment without radiographic evidence of new or worsening PTE. Incidence of PTE/SPTE by site was as follows: base of skull (BOS): 10.3%/6.1%, convexity: 22.7%/7.6%, falcine: 17.6%/4.1%, parasagittal: 27.8%/8.3%, posterior fossa/tentorium 7.0%/0.0%. Incidence of PTE/SPTE by technique was as follows: SRS: 6.3%/3.8%, FSRS: 20.9%/7.4%, FSRT: 15.5%/5.7%. On univariate analysis, age >65 (OR = 2.17 (95% CI: 1.26-3.77) p = 0.006), tumor volume (OR = 1.05 (1.02-1.08), p = 0.003), pre-treatment PTE (OR = 6.82 (95% CI: 3.59-12.94) p<0.001), and convexity/falcine/parasagittal (CFPS) location (OR = 2.52 (95% CI: 1.49-4.23) p<0.001) were associated with increased incidence of PTE. On multivariate analysis, age >65 (OR = 1.91 (95% CI: 1.05-3.45) p<0.03), tumor volume (OR = 1.04 (95% CI: 1.00-1.08) p = 0.03), pre-treatment PTE (OR = 4.64 (95% CI: 2.33-9.24) p<0.001), and CFPS location (OR = 2.53 (95% CI: 1.41-4.52) p = 0.002) were associated with increased incidence of PTE. Two patients with PTE underwent resection for local failure which revealed atypical meningioma.

CONCLUSION

Age >65, larger tumor volume, presence of pre-treatment PTE, and CFPS location were associated with increased incidence of PTE following radiotherapy. Patients with these risk factors should be counseled regarding post-treatment effects. Infrequently, PTE following treatment may be an indicator of higher-grade meningioma.

Impact of Concurrent Targeted Therapy and Immunotherapy on the Incidence of Radiation Necrosis Following Stereotactic Radiosurgery for Brain Metastases

PURPOSE/OBJECTIVE(S)

The management of metastatic disease has evolved with the advent of immunotherapy (IT) and targeted therapies (TT). Yet, there is limited understanding of the toxicity associated with combining these agents with stereotactic radiosurgery (SRS). We retrospectively evaluated the impact of concurrent systemic therapy (ST) on the risk of radiation necrosis (RN) following LINAC-based SRS for brain metastases (BM).

MATERIALS/METHODS

A retrospective study was conducted within an integrated health care system from March 2017 to December 2021 of 313 patients who underwent SRS or fractionated SRS in 3 or 5 treatments to a total of 1,644 intact BM. Post-operative cavity SRS and re-irradiated lesions were excluded. RN was diagnosed using perfusion MRI, contrast clearance MRI, or serial standard MRI and graded using CTCAE (v.5). Concurrent ST was defined as administration within 1 month preceding or following SRS. Overall survival (OS) and risk of RN were estimated by the Kaplan-Meier method. Logistics regression analyses were performed to compare risk of RN in patients who received concurrent systemic therapy to those who did not, adjusted for PTV volume and receipt of whole brain radiotherapy (WBRT).

RESULTS

Median follow-up was 12.2 months. Median age was 64 years (range: 24-92). Primary sites per patient included lung (48.9%), breast (18.2%), melanoma (11.5%), kidney (6.1%), and other (15.3%). Median total lesions treated was 3 (range: 1-44); 65.9% of patients underwent 1 course of SRS, 23.4% underwent 2 courses, 6.2% underwent 3 courses, 4.5% underwent >4 courses. Seventy-six (24.2%) patients received WBRT. Overall, 70.6% of lesions received concurrent ST including chemotherapy (CT) (32.5%), IT (26.8%), and TT (27.6%); 16.4% received a combination of ST. Median OS was 12.9 months (95% CI: 10.4-15.5). RN was observed in 50 (3.0%) lesions in 42 (13.4%) patients. The 1-year risk of RN was 4.0% per lesion and 15.4% per patient. Symptomatic RN (SRN) was observed in 31 (1.9%) lesions in 24 (7.7%) patients. The 1-year risk of SRN was 2.7% per lesion and 10.1% per patient. When compared to lesions treated without concurrent systemic therapy, there was no increased risk of RN observed in lesions treated with concurrent CT (adjusted OR = 0.86 (95% CI: 0.43-1.73) p = 0.68), concurrent IT (adjusted OR = 0.84 (95% CI: 0.41-1.71) p = 0.84), or concurrent TT (adjusted OR = 0.57 (95% CI: 0.25-1.30) p = 0.18). Treatments of SRN included dexamethasone (96.8%), bevacizumab (22.6%), and laser interstitial thermal therapy (6.5%).

CONCLUSION

Concurrent IT and TT appears well-tolerated in patients who undergo SRS for treatment of BM. No increased risk of RN was observed in lesions treated with concurrent IT or TT compared to lesions treated in the absence of concurrent ST. Further prospective and agent-specific evaluation is necessary to confirm these findings.

Adaptive Dose-Staged Stereotactic Ablative Body Radiotherapy for Treatment of Large Central NSCLC Lung Tumors: A Dosimetric Simulation Study

PURPOSE/OBJECTIVE(S)

Adaptive dose-staged Stereotactic Radiosurgery (SRS) treatment of cranial AVM and personalized ultrafractionated stereotactic ablative radiotherapy (PULSAR) proposed by Timmerman et al. for lung cancer has been shown to be an effective technique with lower toxicities in the management of large lesions. The PULSAR technique requires periodic functional PET imaging or tumor biopsy more than one week apart post stereotactic ablative body radiotherapy (SABR) PULSE to utilize the tumor biological response feedback to delineate the residual active disease for subsequent (SABR) PULSES' adaptive treatment planning. The purpose of this study is to explore dosimetrically the benefit of SABR PULSES for the treatment of large central lungs tumors.

MATERIALS/METHODS

A retrospective simulation study of five anonymized patients with large NSCLC was performed. Tumors were located centrally in left (N = 3) and right (N = 2) lungs. The PTVs generated by 5mm symmetric margin to the ITV, the ITV and PTV volumes were 30.0±21.4cc (10.6-64.5cc) and 65.4±35.2cc (30.7-121.0cc), respectively. Depending on the total PTV volume, 4 other adaptive PTVs were simulated by generating a symmetric reduction of the PTV volumes by 2 or 3mm assuming given enough time shrinking the original volume after each PULSE due to biological response during the time between the initial and subsequent SABR PULSES. The organs-at-risk (OARs) were contoured and 3 VMAT arcs plans were generated and optimized for each PTV with the same VMAT objective functions. The original PTV plan with 50 Gy in 5 consecutive fractions was compared with the sum of the 5 PULSES in 10 Gy per PULSE with adaptive volumes. A statistical analysis and a paired t-test of the 50 Gy plan in 5 consecutive fractions were compared with the 5 PULSES summed dose for the ITV, PTV, and the OARs.

RESULTS

The t-test showed the 5 PULSES plans significantly lowered the doses to the ipsilateral, and contralateral lungs and heart when compared to 5 consecutive 10 Gy/fraction plans (p-Values, 0.031, 0.01, 0.02, respectively). The 11 Gy ipsilateral lung volume, a precursor for developing normal lung tissue fibrosis about one-year post SABR was significantly lower for the 5 PULSES (136±44cc Vs. 241±83cc) (p-Value, 0.01). The mean and maximum dose to the original PTV was significantly lower in 5 PULSES technique (p-Value, 0.0001, 0.046). The dose to the spinal canal was not statistically different between the two techniques (p-Value, 0.12).

CONCLUSION

The current management of large central lung tumors is conventional fractionation with chemotherapy or delivering lower fractional SABR dose to meet the OAR dose constraints that may hinder the successful radioablation and local control. The PULSAR treatments using SABR dosimetrically provides significant sparing of normal tissue. Dose escalation for larger central lung tumors may be possible using this technique for effective local control and better overall survivorship.

Clinical Outcomes Following Postoperative Cavity Stereotactic Radiosurgery for Brain Metastases

PURPOSE/OBJECTIVE(S)

We evaluated outcomes of patients with brain metastases (BM) treated with surgical resection and postoperative cavity stereotactic radiosurgery (SRS) to identify which baseline characteristics and treatment factors may increase risk for local recurrence (LR).

MATERIALS/METHODS

From June 2017 to December 2021, 68 patients underwent surgical resection for BM followed by single-fraction SRS (n = 15) or fractionated SRS (FSRS) in 3 (n = 24) or 5 (n = 29) fractions to the postoperative cavity using frameless LINAC-based technique. Patients treated with surgery alone or surgery with postoperative whole brain radiotherapy (WBRT) were excluded. Median prescription doses were 1600 cGy (range: 1440-1875) in 1 fraction, 2400 cGy (range: 2100-2700) in 3 fractions, and 3000 cGy (range: 2500-3000) in 5 fractions. Local control (LC) and overall survival (OS) were estimated by the Kaplan-Meier method. Cox proportional hazards models were used to compare groups.

RESULTS

Median follow-up was 19.5 months (IQR: 9.0-34.7). Median patient age was 62.5 years (range: 24-80), and 38 (55.9%) patients were male. Primary tumors were lung (n = 29), including NSCLC (n = 28) and SCLC (n = 1), melanoma (n = 12), breast (n = 11), and other (n = 16). Median preoperative tumor maximal dimension was 3.5cm (range: 1.1-6.3). Median planning treatment volume (PTV) was larger in the FSRS group (26.2cc (range: 6.5-151.8)) than in the SRS group (7.7cc (range: 1.1-11.5)) (p<0.001). Median number of concurrently treated intact lesions was 0 (range: 0-13). Median time from surgery to SRS was 32 days (range: 14-77). Forty-eight (70.6%) patients were treated with immunotherapy or targeted therapy. Median OS was 22.3 months (95% CI: 14.4-30.9). The 1-year and 2-year OS rates were 70% and 48%, respectively. The 1-year and 2-year LC rates were 86% and 73%, respectively. Median time to LR was 8.4 months (95% CI: 4.4-11.0). Among the 14 patients with LR, 11 had undergone salvage therapy at last follow-up which included repeat SRS (n = 4), WBRT (n = 3), palliative local radiotherapy (n = 2), surgery followed by repeat SRS (n = 1), and systemic therapy (n = 1). Eleven (16.2%) patients ultimately underwent WBRT post-SRS for local and/or distant failure. No difference in LC was observed based on primary tumor, time interval between resection and SRS, PTV volume, prescription dose, or fractionation regimen (SRS v. FSRS). However, all LR in the 3-fraction group occurred in patients who received less than 2700 cGy.

CONCLUSION

Favorable LC and OS outcomes were observed following postoperative cavity SRS for resected BM in a modern cohort with a large percentage of patients receiving immunotherapy or targeted therapy. No prognostic factors were identified for LC which may be attributable to the cohort size and small number of events observed. However, our findings suggest that patients who undergo 3-fraction FSRS should be treated to a total dose of 2700 cGy to maximize LC.

Clinical outcomes after IL-6 blockade in patients with COVID-19 and HIV: a case series

BACKGROUND

In hospitalized people with HIV (PWH) there is an increased risk of mortality from COVID-19 among hospitalized PWH as compared to HIV-negative individuals. Evidence suggests that tocilizumab-a humanized monoclonal interleukin (IL)-6 receptor inhibitor (IL-6ri) antibody-has a modest mortality benefit when combined with corticosteroids in select hospitalized COVID-19 patients who are severely ill. Data on clinical outcomes after tocilizumab use in PWH with severe COVID-19 are lacking.

CASE PRESENTATION

We present a multinational case series of 18 PWH with COVID-19 who were treated with IL-6ri's during the period from April to June 2020. Four patients received tocilizumab, six sarilumab, and eight received an undocumented IL-6ri. Of the 18 patients in the series, 4 (22%) had CD4 counts < 200 cells/mm³; 14 (82%) had a suppressed HIV viral load. Eight patients (44%), all admitted to ICU, were treated for secondary infection; 5 had a confirmed organism. Of the four patients with CD4 counts < 200 cells/mm³, three were treated for secondary infection, with 2 confirmed organisms. Overall outcomes were poor-12 patients (67%) were admitted to the ICU, 11 (61%) required mechanical ventilation, and 7 (39%) died.

CONCLUSIONS

In this case series of hospitalized PWH with COVID-19 and given IL-6ri prior to the common use of corticosteroids, there are reports of secondary or co-infection in severely ill patients. Comprehensive studies in PWH, particularly with CD4 counts < 200 cells, are warranted to assess infectious and other outcomes after IL-6ri use, particularly in the context of co-administered corticosteroids.

Zinc sulfate in combination with a zinc ionophore may improve outcomes in hospitalized COVID-19 patients

Introduction. COVID-19 has rapidly emerged as a pandemic infection that has caused significant mortality and economic losses. Potential therapies and prophylaxis against COVID-19 are urgently needed to combat this novel infection. As a result of in vitro evidence suggesting zinc sulphate may be efficacious against COVID-19, our hospitals began using zinc sulphate as add-on therapy to hydroxychloroquine and azithromycin.Aim. To compare outcomes among hospitalized COVID-19 patients ordered to receive hydroxychloroquine and azithromycin plus zinc sulphate versus hydroxychloroquine and azithromycin alone.Methodology. This was a retrospective observational study. Data was collected from medical records for all patients with admission dates ranging from 2 March 2020 through to 11 April 2020. Initial clinical characteristics on presentation, medications given during the hospitalization, and hospital outcomes were recorded. The study included patients admitted to any of four acute care NYU Langone Health Hospitals in New York City. Patients included were admitted to the hospital with at least one positive COVID-19 test and had completed their hospitalization. Patients were excluded from the study if they were never admitted to the hospital or if there was an order for other investigational therapies for COVID-19.Results. Patients taking zinc sulphate in addition to hydroxychloroquine and azithromycin (n=411) and patients taking hydroxychloroquine and azithromycin alone (n=521) did not differ in age, race, sex, tobacco use or relevant comorbidities. The addition of zinc sulphate did not impact the length of hospitalization, duration of ventilation or intensive care unit (ICU) duration. In univariate analyses, zinc sulphate increased the frequency of patients being discharged home, and decreased the need for ventilation, admission to the ICU and mortality or transfer to hospice for patients who were never admitted to the ICU. After adjusting for the time at which zinc sulphate was added to our protocol, an increased frequency of being discharged home (OR 1.53, 95 % CI 1.12-2.09) and reduction in mortality or transfer to hospice among patients who did not require ICU level of care remained significant (OR 0.449, 95 % CI 0.271-0.744).Conclusion. This study provides the first in vivo evidence that zinc sulphate may play a role in therapeutic management for COVID-19.

Characteristics, Comorbidities, and Outcomes in a Multicenter Registry of Patients with HIV and Coronavirus Disease-19

Background

People with HIV (PWH) may have numerous risk factors for acquiring Coronavirus disease-19 (COVID-19) and developing severe outcomes, but current data are conflicting.

Methods

Healthcare providers enrolled consecutively by non-random sampling PWH with lab-confirmed COVID-19, diagnosed at their facilities between April 1st and July 1st, 2020. De-identified data were entered into an electronic Research Electronic Data Capture (REDCap). The primary endpoint was severe outcome, defined as a composite endpoint of intensive care unit (ICU) admission, mechanical ventilation, or death. The secondary outcome was the need for hospitalization.

Results

286 patients were included; the mean age was 51.4 years (SD, 14.4), 25.9% were female, and 75.4% were African-American or Hispanic. Most patients (94.3%) were on antiretroviral therapy (ART), 88.7% had HIV virologic suppression, and 80.8% had comorbidities. Within 30 days of positive SARS-CoV-2 testing, 164 (57.3%) patients were hospitalized, and 47 (16.5%) required ICU admission. Mortality rates were 9.4% (27/286) overall, 16.5% (27/164) among those hospitalized, and 51.5% (24/47) among those admitted to an ICU. The primary composite endpoint occurred in 17.5% (50/286) of all patients and 30.5% (50/164) of hospitalized patients. Older age, chronic lung disease, and hypertension were associated with severe outcomes. A lower CD4 count (<200 cells/mm³) was associated with the primary and secondary endpoints. There was no association between the antiretroviral regimen or lack of viral suppression and predefined outcomes.

Conclusion

Severe clinical outcomes occurred commonly in PWH and COVID-19. The risk for poor outcomes was higher in those with comorbidities and lower CD4 cell counts, despite HIV viral suppression.

Does Nasal Colonization or Mupirocin Treatment Affect Recurrence of Methicillin-Resistant Staphylococcus aureus Skin and Skin Structure Infections?

Some patients with community-associated methicillin-resistant Staphylococcus aureus skin and skin structure infections have experienced frequent recurrences. We performed a retrospective study and determined that the presence of nasal colonization did not affect recurrence and nasal mupirocin treatment marginally decreased recurrence

Evaluation of Treatment Courses When Vancomycin Is Given Every 8 Hours in Adult Patients

BACKGROUND

Several nomograms include recommendations to give intravenous (IV) vancomycin at 8-hour dosing intervals (Q8H). However, there is a lack of detailed data regarding this dosing recommendation.

METHODS

A retrospective chart review of 100 patients who received 107 treatment courses of vancomycin Q8H for at least 5 days was performed. Distribution of vancomycin trough levels and rate of nephrotoxicity were evaluated.

RESULTS

Median patient age was 38 years (interquartile range [IQR] 27-50 years), median weight was 67 kg (IQR 55-79 kg), and median creatinine clearance was 124 mL/min (IQR 101-147 mL/min). Median duration of Q8H dosing was 9 days (IQR 7-12 days). Within the initial 96 hours, only 7% (7 of 104) of maximum trough concentrations were >20 mg/L (median dose 15 mg/kg [IQR 15-18 mg/kg]). After 96 hours of Q8H dosing, 34% (30 of 89) of maximum troughs were >20 mg/L (median dose 17 mg/kg [IQR 15-20 mg/kg]), P = .0005. The rate of nephrotoxicity was 4%.

CONCLUSION

We observed an increase in the percentage of trough levels >20 mg/L later during treatment courses of vancomycin IV Q8H with a relatively small corresponding increase in vancomycin dose. Close monitoring of trough levels (eg, every 3 days) with prolonged courses of vancomycin IV Q8H is warranted.

Infection with panresistant Klebsiella pneumoniae: a report of 2 cases and a brief review of the literature

Infections caused by carbapenemase-producing Klebsiella pneumoniae have been reported with increasing frequency, thereby limiting the choice of effective antimicrobial agents available to clinicians. This has prompted the increased use of polymyxins and tigecycline, but resistance to these agents is already emerging. We report 2 cases of infection with panresistant K. pneumoniae.

Identification of novel hsp65 RFLPs for Mycobacterium leprae

Leprosy or Hansen's disease is a chronic infectious disease caused by an acid-fast bacillus, Mycobacterium leprae (M. leprae). The bacilli proliferate in macrophages infiltrating the skin and gain entry to the dermal nerves via the laminar surface of Schwann cells where they replicate. After entry, the Schwann cells proliferate and then die. Conclusive identification of M. leprae DNA in a sample can be obtained by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for the heat shock 65 gene (hsp65). Molecular epidemiology will make it possible to study the global distributions of M. leprae, explore the relationship between genotypes-incidence rates, mode of transmission, and the type of disease (tuberculoid vs. lepromatous). We amplified DNA using PCR for the hsp65 gene from 24 skin lesions from patients diagnosed with various types of leprosy. Fifteen out of 24 were positive for the hsp65 gene. Digestion with HaeIII-PAGE for the RFLP confirmation of the presence of M. leprae DNA showed the typical pattern in 5 out of 24 and 2 novel patterns in 10 out of 24 patients. We confirmed the presence of M. leprae DNA by sequencing the genes for gyraseA or B and folP, which contained only M. leprae specific single nucleotide polymorphisms (SNPs). Thus, we describe novel hsp65 RFLPs for M. leprae found in a high frequency making them ideal for future epidemiology and transmission studies.

Bartonella quintana endocarditis with positive serology for Coxiella burnetii

Both Bartonella quintana and Coxiella burnetii are known to cause of blood culture negative endocarditis. In such case, the diagnosis is usually established by serology. A case of Bartonella quintana endocarditis is described where the serology was falsely positive for Coxiella burnetii. This case demonstrates the difficulty in distinguishing these two etiologic agents by routine serologic testing.