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Chen XS, Sher DJ, Sullivan CB, Repka MC, Shen CJ, Chera B. Target Delineation in Postoperative Radiation Therapy for Head and Neck Cancer After Flap Reconstruction. Pract Radiat Oncol 2024:S1879-8500(24)00081-X. [PMID: 38636587 DOI: 10.1016/j.prro.2024.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 04/01/2024] [Accepted: 04/02/2024] [Indexed: 04/20/2024]
Abstract
Delineation of the clinical target volume (CTV) after resection of head and neck cancer can be challenging, especially after flap reconstruction. The main area of contention is whether the entire flap should be included in the CTV. Several case series have reported marginal misses and intraflap failures when the entire flap was not routinely included in the CTV. On the other hand, available data have not convincingly demonstrated a detriment to long-term outcomes using intensity modulated radiotherapy after flap reconstruction. On the contrary, postoperative radiation can facilitate epilation and mucosalization of the flap tissue, reduce flap bulk, and improve long-term esthetic and functional outcomes. Therefore, our standard practice is to include the entire flap in the CTV. In certain scenarios, we may allow for a lower dose to part of flap distant from the resection bed than the flap-tumor bed junction, where recurrences are most likely. We provide three case vignettes describing such scenarios where sparing part of the flap, and more importantly, the nearby uninvolved native tissue, from high-dose radiation may be justified.
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Affiliation(s)
- Xuguang Scott Chen
- Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina.
| | - David J Sher
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Christopher Blake Sullivan
- Department of Otolaryngology-Head and Neck Surgery, University of North Carolina, Chapel Hill, North Carolina
| | - Michael C Repka
- Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina
| | - Colette J Shen
- Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina
| | - Bhisham Chera
- Department of Radiation Oncology, Medical University of South Carolina, Charleston, South Carolina
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Repka MC, Sholklapper T, Zwart AL, Danner M, Ayoob M, Yung T, Lei S, Collins BT, Kumar D, Suy S, Hankins RA, Kishan AU, Collins SP. Prognostic utility of biopsy-based PTEN and ERG status on biochemical progression and overall survival after SBRT for localized prostate cancer. Front Oncol 2024; 14:1381134. [PMID: 38585005 PMCID: PMC10995255 DOI: 10.3389/fonc.2024.1381134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 03/12/2024] [Indexed: 04/09/2024] Open
Abstract
Introduction/background Phosphatase and tensin homolog (PTEN) genomic deletions and transmembrane protease, serine 2/v-ets avian erthyroblastosis virus E26 oncogene homolog (ERG) rearrangements are two of the most common genetic abnormalities associated with prostate cancer. Prior studies have demonstrated these alterations portend worse clinical outcomes. Our objective is to evaluate the impact of biopsy-determined PTEN losses and TMPRSS2-ERG fusion on biochemical progression-free survival (bPFS) and overall survival (OS) in patients who receive SBRT for localized prostate cancer. Methods/materials Patients received SBRT for localized prostate cancer on a prospective quality-of-life (QoL) and cancer outcomes study. For each patient, the single biopsy core with the highest grade/volume of cancer was evaluated for PTEN and ERG abnormalities. Differences in baseline patient and disease characteristics between groups were analyzed using ANOVA for age and χ2 for categorical groupings. bPFS and OS were calculated using the Kaplan Meier (KM) method with Log-Rank test comparison between groups. Predictors of bPFS and OS were identified using the Cox proportional hazards method. For all analyses, p <0.05 was considered statistically significant. Results Ninety-nine consecutive patients were included in the analysis with a median follow-up of 72 months. A statistically significant improvement in bPFS (p = 0.018) was observed for wild type ERG patients with an estimated 5-year bPFS of 94.1% vs. 72.4%. Regarding PTEN mutational status, significant improvements in were observed in both bPFS (p = 0.006) and OS (p < 0.001), with estimated 5-year bPFS rates of 91.0% vs. 67.9% and 5-year OS rates of 96.4% vs. 79.4%. When including both ERG and PTEN mutational status in the analysis, there were statistically significant differences in both bPFS (p = 0.011) and OS (p < 0.001). The estimated 5-year bPFS rates were 100%, 76.6%, 72.9%, and 63.8% for patients with ERG+/PTEN+, ERG-/PTEN+, ERG+/PTEN-, and ERG-/PTEN- phenotypes respectively. The estimated 5-year OS rates were 93.9%, 100%, 80.0%, and 78.7% for patients with ERG+/PTEN+, ERG-/PTEN+, ERG+/PTEN-, and ERG-/PTEN- phenotypes respectively. Conclusion ERG rearrangements and PTEN deletions detected on biopsy samples are associated with poorer oncologic outcomes in prostate cancer patients treated with SBRT and merit further study in a dedicated prospective trial.
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Affiliation(s)
- Michael C. Repka
- Department of Radiation Oncology, University of North Carolina (UNC) School of Medicine, Chapel Hill, NC, United States
| | - Tamir Sholklapper
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Alan L. Zwart
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Malika Danner
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Marilyn Ayoob
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Thomas Yung
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Siyuan Lei
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Brian T. Collins
- Department of Radiation Oncology, Tampa General Hospital, Tampa, FL, United States
| | - Deepak Kumar
- Julius L Chambers Research Institute, North Carolina Central University, Durham, NC, United States
| | - Simeng Suy
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Ryan A. Hankins
- Department of Urology, Georgetown University Hospital, Washington, DC, United States
| | - Amar U. Kishan
- Department of Radiation Oncology, University of California, Los Angeles (UCLA) Health, Los Angeles, CA, United States
| | - Sean P. Collins
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
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Lischalk JW, Akerman M, Repka MC, Sanchez A, Mendez C, Santos VF, Carpenter T, Wise D, Corcoran A, Lepor H, Katz A, Haas JA. High-risk prostate cancer treated with a stereotactic body radiation therapy boost following pelvic nodal irradiation. Front Oncol 2024; 14:1325200. [PMID: 38410097 PMCID: PMC10895712 DOI: 10.3389/fonc.2024.1325200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 01/08/2024] [Indexed: 02/28/2024] Open
Abstract
Purpose Modern literature has demonstrated improvements in long-term biochemical outcomes with the use of prophylactic pelvic nodal irradiation followed by a brachytherapy boost in the management of high-risk prostate cancer. However, this comes at the cost of increased treatment-related toxicity. In this study, we explore the outcomes of the largest cohort to date, which uses a stereotactic body radiation therapy (SBRT) boost following pelvic nodal radiation for exclusively high-risk prostate cancer. Methods and materials A large institutional database was interrogated to identify all patients with high-risk clinical node-negative prostate cancer treated with conventionally fractionated radiotherapy to the pelvis followed by a robotic SBRT boost to the prostate and seminal vesicles. The boost was uniformly delivered over three fractions. Toxicity was measured using the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Oncologic outcomes were assessed using the Kaplan-Meier method. Cox proportional hazard models were created to evaluate associations between pretreatment characteristics and clinical outcomes. Results A total of 440 patients with a median age of 71 years were treated, the majority of whom were diagnosed with a grade group 4 or 5 disease. Pelvic nodal irradiation was delivered at a total dose of 4,500 cGy in 25 fractions, followed by a three-fraction SBRT boost. With an early median follow-up of 2.5 years, the crude incidence of grade 2+ genitourinary (GU) and gastrointestinal (GI) toxicity was 13% and 11%, respectively. Multivariate analysis revealed grade 2+ GU toxicity was associated with older age and a higher American Joint Committee on Cancer (AJCC) stage. Multivariate analysis revealed overall survival was associated with patient age and posttreatment prostate-specific antigen (PSA) nadir. Conclusion Utilization of an SBRT boost following pelvic nodal irradiation in the treatment of high-risk prostate cancer is oncologically effective with early follow-up and yields minimal high-grade toxicity. We demonstrate a 5-year freedom from biochemical recurrence (FFBCR) of over 83% with correspondingly limited grade 3+ GU and GI toxicity measured at 3.6% and 1.6%, respectively. Long-term follow-up is required to evaluate oncologic outcomes and late toxicity.
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Affiliation(s)
- Jonathan W. Lischalk
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University Langone Hospital - Long Island, New York, NY, United States
| | - Meredith Akerman
- Division of Health Services Research, New York University Long Island School of Medicine, New York University Langone Health, Mineola, NY, United States
| | - Michael C. Repka
- Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC, United States
| | - Astrid Sanchez
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University Langone Hospital - Long Island, New York, NY, United States
| | - Christopher Mendez
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University Langone Hospital - Long Island, New York, NY, United States
| | - Vianca F. Santos
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University Langone Hospital - Long Island, New York, NY, United States
| | - Todd Carpenter
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University Langone Hospital - Long Island, New York, NY, United States
| | - David Wise
- Department of Medical Oncology, Perlmutter Cancer Center at New York University Langone Health - Manhattan, New York, NY, United States
| | - Anthony Corcoran
- Department of Urology, Perlmutter Cancer Center at New York University Langone Hospital - Long Island, New York, NY, United States
| | - Herbert Lepor
- Department of Urology, Perlmutter Cancer Center at New York University Grossman School of Medicine, New York, NY, United States
| | - Aaron Katz
- Department of Urology, Perlmutter Cancer Center at New York University Langone Hospital - Long Island, New York, NY, United States
| | - Jonathan A. Haas
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University Langone Hospital - Long Island, New York, NY, United States
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Morse R, Beaty B, Moon DH, Green R, Xu V, Weiss J, Sheth S, Patel S, Blumberg J, Hackman T, Lumley C, Patel S, Yarbrough W, Huff SB, Repka MC, Dagan R, Amdur RJ, Chera BS, Shen C, Chen X. Long-Term Outcomes of De-Intensified Chemoradiotherapy for Human Papillomavirus-Associated Oropharyngeal Squamous Cell Carcinoma. Int J Radiat Oncol Biol Phys 2023; 117:S123-S124. [PMID: 37784319 DOI: 10.1016/j.ijrobp.2023.06.464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) To report long-term oncologic outcomes among patients with human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) treated with definitive de-intensified chemoradiotherapy. MATERIALS/METHODS Major criteria for de-intensification were (1) AJCC 7th edition T0-T3, N0-N2c, M0 (AJCC 8th edition T0-T3, N0-N2, M0), (2) pathologically confirmed p16 positive, and (3) no or minimal/remote smoking history (non-mutated p53 if ≥30 pack-years). Treatment was 60 Gy intensity-modulated radiotherapy with first-choice concurrent cisplatin 30 mg/m2 once per week (alternative regimens permissible for cisplatin ineligible patients). Patients with T0-T2 N0-1 (AJCC 7th edition) were recommended 60 Gy radiation alone. Systemic therapy received included: cisplatin 30 mg/m2 (n = 122), cetuximab (n = 15), cisplatin 40 mg/m2 (n = 12), carboplatin/paclitaxel (n = 2), and radiation alone (n = 25). Kaplan Meier estimates for overall survival (OS), progression-free survival (PFS), locoregional control (LRC), and freedom from distant metastasis (FFDM) were calculated. Cox regression models were used for comparisons among subgroups. RESULTS A total 176 patients received de-intensified treatment (n = 153 prospective protocol, n = 23 off-protocol). Median follow-up was 52.6 months (range 5.3 - 102.0, 90.8% with minimum 2-year follow-up); 56.8% (n = 100) were never smokers and 43.2% (n = 76) former smokers; former smokers had median 9 pack-years smoking history (range 0.25 - 50) with 46% ≥10 pack-years. Outcomes were as follows: 2-year OS 99.4% and 5-year OS 91.8%; 2-year PFS 94.1% and 5-year PFS 84.3%; 2-year LRC 98.3% and 5-year LRC 95.8%; 2-year FFDM 95.8% and 5-year FFDM 93.2%. Median time to progression events were 21.1 months (range, 7.2 - 54.1) with 37.5% (6 of 16) of recurrences occurring after 24 months. Six total locoregional events occurred (five recurrences and one site of persistent disease), within the 60 Gy planning target volume. Twenty-three patients with T0-T2 N0-1 disease received radiation alone with 2-year PFS 92.9% (5-year 83.8%) and 2-year LRC 100% (5-year 95.2%). Outcomes for former smokers with ≥10 pack-years were comparable to patients with less or no smoking history (2-year PFS 94.1% vs 94.1%; 5-year PFS 90.6% vs 82.7%; HR 0.58, p = 0.38). Early results suggest similar oncologic outcomes among those treated off-protocol (median follow-up 25.6 months) with 1 of 23 patients experiencing locoregional recurrence. CONCLUSION Dose de-intensification of 60 Gy radiotherapy with weekly cisplatin results in favorable long-term tumor control in patients with HPV-associated OPSCC. De-intensified 60 Gy alone may be efficacious in carefully selected patients with T0-T2 N0-1 (AJCC 7th edition) disease. Inclusion of biologically favorable patients with more extensive former smoking history in de-intensification clinical trials may be warranted.
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Affiliation(s)
- R Morse
- Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC
| | - B Beaty
- Albert Einstein College of Medicine, Bronx, NY
| | - D H Moon
- University of Texas Southwestern Department of Radiation Oncology, Dallas, TX
| | - R Green
- University of North Carolina Hospitals, Chapel Hill, NC
| | - V Xu
- University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - J Weiss
- University of North Carolina Lineberger Comprehensive Cancer Center, Chapel Hill, NC
| | - S Sheth
- University of North Carolina Lineberger Comprehensive Cancer Center, Chapel Hill, NC
| | - S Patel
- University of North Carolina Hospitals, Chapel Hill, NC
| | | | - T Hackman
- Department of Otolaryngology, University of North Carolina School of Medicine, Chapel Hill, NC
| | - C Lumley
- UNC School of Medicine, Chapel Hill, NC
| | - S Patel
- UNC School of Medicine, Chapel Hill, NC
| | | | - S B Huff
- University of Carolina, Chapel Hill, NC
| | - M C Repka
- Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC
| | - R Dagan
- University of Florida Health Proton Therapy Institute, Jacksonville, FL
| | - R J Amdur
- University of Florida Hospitals, Gainesville, FL
| | - B S Chera
- Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - C Shen
- Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC
| | - X Chen
- Case Western Reserve University School of Medicine, Cleveland, OH
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Hall J, Dance MJ, Nguyen L, Repka MC, Chen X, Shen C. Hippocampal-Sparing Radiotherapy in Primary Sinonasal and Cutaneous Head and Neck Malignancies: A Feasibility Study. Int J Radiat Oncol Biol Phys 2023; 117:e586-e587. [PMID: 37785776 DOI: 10.1016/j.ijrobp.2023.06.1931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Patients with primary sinonasal and cutaneous head and neck (H&N) malignancies often receive meaningful hippocampal doses, but the hippocampus is not a classic avoidance structure in radiation planning of these primary sites. This series characterizes the feasibility and tradeoffs of hippocampal-sparing radiotherapy (HSRT) for patients with primary sinonasal and cutaneous H&N malignancies. MATERIALS/METHODS We retrospectively identified patients at a single institution treated definitively for primary sinonasal or cutaneous malignancies of the H&N. Each patient received (chemo)radiation and all received clinically-significant radiation dose to one or both hippocampi. We created new HSRT plans for each patient with intensity-modulated radiotherapy using original target and organ-at-risk (OAR) volumes. Hippocampi were contoured based on Radiation Therapy Oncology Group guidelines. Absolute and relative differences in radiation dose to the hippocampi, planning target volumes (PTV), and OARs were recorded. We used paired-samples t-tests to compare hippocampal and PTV dosimetric measures with and without HSRT. RESULTS Thirty-seven patients were included (22 sinonasal, 11 cutaneous H&N, and 4 parotid primary tumors). Median prescription dose was 6600cGy (range: 5000-7440cGy). The most common fractionation regimens were 200cGy/fraction daily (51%, 19/37 patients) and 120cGy/fraction twice daily (41%, 15/37 patients). There were significant decreases in hippocampal Dmax and D100% using HSRT without compromising PTV coverage (Table 1). HSRT resulted in a relative increase of mean lacrimal gland dose by an average of 3.8%, optic chiasm Dmax by 1.3%, and whole brain Dmax of 1.2%. However, other OAR doses were lower with HSRT, including parotid gland mean dose, lens Dmax, optic nerve Dmax, cochlea mean dose, brainstem Dmax, and whole brain mean dose. CONCLUSION HSRT is feasible and results in meaningful radiation dose reduction to the hippocampi without reducing PTV coverage or increasing dose to other OARs. The hippocampi should be regularly included as avoidance structures when treating primary sinonasal and cutaneous H&N tumors with radiation. We suggest target hippocampal constraints of Dmax < 1600cGy and D100% < 500cGy when feasible (without compromising PTV coverage). The clinical significance of HSRT in patients with primary H&N tumors should be investigated prospectively.
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Affiliation(s)
- J Hall
- Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC
| | - M J Dance
- Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC
| | - L Nguyen
- North Carolina School of Science and Mathematics, Durham, NC
| | - M C Repka
- Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC
| | - X Chen
- Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC
| | - C Shen
- Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC
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Leu J, Akerman M, Mendez C, Lischalk JW, Carpenter T, Ebling D, Haas JA, Witten M, Barbaro M, Duic P, Tessler L, Repka MC. Corrigendum: Time interval from diagnosis to treatment of brain metastases with stereotactic radiosurgery is not associated with radionecrosis or local failure. Front Oncol 2023; 13:1192726. [PMID: 37093946 PMCID: PMC10113650 DOI: 10.3389/fonc.2023.1192726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 03/29/2023] [Indexed: 04/08/2023] Open
Abstract
[This corrects the article DOI: 10.3389/fonc.2023.1132777.].
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Affiliation(s)
- Justin Leu
- Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, United States
| | - Meredith Akerman
- Division of Health Services Research, New York University (NYU) Long Island School of Medicine, Mineola, NY, United States
| | - Christopher Mendez
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
| | - Jonathan W. Lischalk
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
- NYCyberKnife at Perlmutter Cancer Center – Manhattan, New York, NY, United States
| | - Todd Carpenter
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
| | - David Ebling
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
| | - Jonathan A. Haas
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
- NYCyberKnife at Perlmutter Cancer Center – Manhattan, New York, NY, United States
| | - Matthew Witten
- Department of Medical Physics, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
| | - Marissa Barbaro
- Department of Neurology, New York University (NYU) Long Island School of Medicine, Mineola, NY, United States
| | - Paul Duic
- Department of Neurology, New York University (NYU) Long Island School of Medicine, Mineola, NY, United States
| | - Lee Tessler
- Department of Neurosurgery, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
| | - Michael C. Repka
- Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC, United States
- *Correspondence: Michael C. Repka,
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Leu J, Akerman M, Mendez C, Lischalk JW, Carpenter T, Ebling D, Haas JA, Witten M, Barbaro M, Duic P, Tessler L, Repka MC. Time interval from diagnosis to treatment of brain metastases with stereotactic radiosurgery is not associated with radionecrosis or local failure. Front Oncol 2023; 13:1132777. [PMID: 37091181 PMCID: PMC10113671 DOI: 10.3389/fonc.2023.1132777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 03/07/2023] [Indexed: 04/09/2023] Open
Abstract
IntroductionBrain metastases are the most common intracranial tumor diagnosed in adults. In patients treated with stereotactic radiosurgery, the incidence of post-treatment radionecrosis appears to be rising, which has been attributed to improved patient survival as well as novel systemic treatments. The impacts of concomitant immunotherapy and the interval between diagnosis and treatment on patient outcomes are unclear.MethodsThis single institution, retrospective study consisted of patients who received single or multi-fraction stereotactic radiosurgery for intact brain metastases. Exclusion criteria included neurosurgical resection prior to treatment and treatment of non-malignant histologies or primary central nervous system malignancies. A univariate screen was implemented to determine which factors were associated with radionecrosis. The chi-square test or Fisher’s exact test was used to compare the two groups for categorical variables, and the two-sample t-test or Mann-Whitney test was used for continuous data. Those factors that appeared to be associated with radionecrosis on univariate analyses were included in a multivariable model. Univariable and multivariable Cox proportional hazards models were used to assess potential predictors of time to local failure and time to regional failure.ResultsA total of 107 evaluable patients with a total of 256 individual brain metastases were identified. The majority of metastases were non-small cell lung cancer (58.98%), followed by breast cancer (16.02%). Multivariable analyses demonstrated increased risk of radionecrosis with increasing MRI maximum axial dimension (OR 1.10, p=0.0123) and a history of previous whole brain radiation therapy (OR 3.48, p=0.0243). Receipt of stereotactic radiosurgery with concurrent immunotherapy was associated with a decreased risk of local failure (HR 0.31, p=0.0159). Time interval between diagnostic MRI and first treatment, time interval between CT simulation and first treatment, and concurrent immunotherapy had no impact on incidence of radionecrosis or regional failure.DiscussionAn optimal time interval between diagnosis and treatment for intact brain metastases that minimizes radionecrosis and maximizes local and regional control could not be identified. Concurrent immunotherapy does not appear to increase the risk of radionecrosis and may improve local control. These data further support the safety and synergistic efficacy of stereotactic radiosurgery with concurrent immunotherapy.
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Affiliation(s)
- Justin Leu
- Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, United States
| | - Meredith Akerman
- Division of Health Services Research, New York University (NYU) Long Island School of Medicine, Mineola, NY, United States
| | - Christopher Mendez
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
| | - Jonathan W. Lischalk
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
- NYCyberKnife at Perlmutter Cancer Center – Manhattan, New York, NY, United States
| | - Todd Carpenter
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
| | - David Ebling
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
| | - Jonathan A. Haas
- Department of Radiation Oncology, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
- NYCyberKnife at Perlmutter Cancer Center – Manhattan, New York, NY, United States
| | - Matthew Witten
- Department of Medical Physics, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
| | - Marissa Barbaro
- Department of Neurology, New York University (NYU) Long Island School of Medicine, Mineola, NY, United States
| | - Paul Duic
- Department of Neurology, New York University (NYU) Long Island School of Medicine, Mineola, NY, United States
| | - Lee Tessler
- Department of Neurosurgery, Perlmutter Cancer Center at New York University (NYU) Long Island, Mineola, NY, United States
| | - Michael C. Repka
- Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC, United States
- *Correspondence: Michael C. Repka,
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Repka MC, Carrasquilla M, Paydar I, Wu B, Lei S, Suy S, Collins SP, Kole TP. Dosimetric predictors of acute bowel toxicity after Stereotactic Body Radiotherapy (SBRT) in the definitive treatment of localized prostate cancer. Acta Oncol 2023; 62:174-179. [PMID: 36826994 DOI: 10.1080/0284186x.2023.2180661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
INTRODUCTION SBRT is an increasingly popular treatment for localized prostate cancer, though considerable variation in technical approach is common and optimal dose constraints are uncertain. In this study, we sought to identify dosimetric and patient-related predictors of acute rectal toxicity. METHODS Patients included in this study were treated with prostate SBRT on a prospective institutional protocol. Physician-graded toxicity and patient-reported outcomes were captured at one week, one month, and three months following SBRT. DVH data were extracted and converted into relative volume differential DVHs for NTCP modeling. Patient- and disease-related covariates along with NTCP model predictions were independently tested for significant association with physician-graded toxicity or a decline in bowel-related QoL. A multivariate model was constructed using forward selection, and significant parameter cutoff values were obtained with Fischer's exact test to group patients by risk of developing physician-graded toxicity or detriments in patient-reported QoL. RESULTS One hundred and three patients treated for localized prostate cancer with SBRT were included in our analysis. 52% of patients experienced a clinically significant decline in bowel-related QOL within 1 week of completion of treatment, while only 27.5% of patients developed grade 2+ physician-graded rectal toxicity. Sequential feature selection multivariate logistic regression identified rectal V22.5 Gy (p = 0.001) and D19% (p = 0.001) as independent predictors of clinically significant toxicity, while rectal V20Gy (p = 0.004) and D25.3% (p = 0.007) were independently correlated with physician-graded toxicity. Global multivariate step-wise logistic regression identified only D19% (p = 0.001) and V20Gy (p = 0.004) as independent predictors of acute bowel bother or physician-graded rectal toxicity respectively. CONCLUSIONS Moderate doses to large rectal volumes, D19% and V20Gy, were associated with an increased incidence of a clinically significant decrease in patient-reported bowel QOL and physician-scored grade 2+ rectal toxicity, respectively. These dosimetric parameters may help practitioners mitigate acute toxicity in patients treated with prostate SBRT.
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Affiliation(s)
- Michael C Repka
- Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - Michael Carrasquilla
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | | | - Binbin Wu
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - Siyuan Lei
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Simeng Suy
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Sean P Collins
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Thomas P Kole
- Department of Radiation Oncology, Valley Mount Sinai Comprehensive Cancer Care, Paramus, NJ, USA
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9
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DiBartolo D, Carpenter T, Santoro JP, Lischalk JW, Ebling D, Haas JA, Witten M, Rybstein M, Vaezi A, Repka MC. Novel VMAT planning technique improves dosimetry for head and neck cancer patients undergoing definitive chemoradiotherapy. Acta Oncol 2023; 62:189-193. [PMID: 36790072 DOI: 10.1080/0284186x.2023.2177973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Affiliation(s)
- David DiBartolo
- Department of Medical Physics, Perlmutter Cancer Center at NYU Long Island, Mineola, NY
| | - Todd Carpenter
- Department of Radiation Oncology, Perlmutter Cancer Center at NYU Long Island, Mineola, NY
| | - Joseph P Santoro
- Department of Medical Physics, Perlmutter Cancer Center at NYU Long Island, Mineola, NY
| | - Jonathan W Lischalk
- Department of Radiation Oncology, Perlmutter Cancer Center at NYU Long Island, Mineola, NY.,NYCyberKnife at Perlmutter Cancer Center Manhattan, New York, NY, USA
| | - David Ebling
- Department of Radiation Oncology, Perlmutter Cancer Center at NYU Long Island, Mineola, NY
| | - Jonathan A Haas
- Department of Radiation Oncology, Perlmutter Cancer Center at NYU Long Island, Mineola, NY.,NYCyberKnife at Perlmutter Cancer Center Manhattan, New York, NY, USA
| | - Matthew Witten
- Department of Medical Physics, Perlmutter Cancer Center at NYU Long Island, Mineola, NY
| | - Marissa Rybstein
- Division of Hematology/Oncology, Perlmutter Cancer Center at NYU Long Island, Mineola, NY, USA
| | - Alec Vaezi
- Department of Otolaryngology-Head and Neck Surgery, Perlmutter Cancer Center at NYU Long Island, Mineola, NY, USA
| | - Michael C Repka
- Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC, USA
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10
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Repka MC, Creswell M, Lischalk JW, Carrasquilla M, Forsthoefel M, Lee J, Lei S, Aghdam N, Kataria S, Obayomi-Davies O, Collins BT, Suy S, Hankins RA, Collins SP. Rationale for Utilization of Hydrogel Rectal Spacers in Dose Escalated SBRT for the Treatment of Unfavorable Risk Prostate Cancer. Front Oncol 2022; 12:860848. [PMID: 35433457 PMCID: PMC9008358 DOI: 10.3389/fonc.2022.860848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 03/14/2022] [Indexed: 11/13/2022] Open
Abstract
In this review we outline the current evidence for the use of hydrogel rectal spacers in the treatment paradigm for prostate cancer with external beam radiation therapy. We review their development, summarize clinical evidence, risk of adverse events, best practices for placement, treatment planning considerations and finally we outline a framework and rationale for the utilization of rectal spacers when treating unfavorable risk prostate cancer with dose escalated Stereotactic Body Radiation Therapy (SBRT).
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Affiliation(s)
- Michael C Repka
- Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, NC, United States
| | - Michael Creswell
- Georgetown University School of Medicine, Washington, DC, United States
| | - Jonathan W Lischalk
- Department of Radiation Oncology at New York University (NYU) Long Island School of Medicine, Perlmutter Cancer Center at NYCyberKnife, New York, NY, United States
| | - Michael Carrasquilla
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Matthew Forsthoefel
- Department of Radiation Oncology, Radiotherapy Centers of Kentuckiana, Louisville, KY, United States
| | - Jacqueline Lee
- Georgetown University School of Medicine, Washington, DC, United States
| | - Siyuan Lei
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Nima Aghdam
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Boston, MA, United States
| | - Shaan Kataria
- Department of Radiation Oncology, Arlington & Reston Radiation Oncology, Arlington, VA, United States
| | - Olusola Obayomi-Davies
- Department of Radiation Oncology, Wellstar Kennestone Hospital, Marietta, GA, United States
| | - Brian T Collins
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Simeng Suy
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Ryan A Hankins
- Department of Urology, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Sean P Collins
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
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11
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Aghdam N, Repka MC, McGunigal M, Pepin A, Paydar I, Rudra S, Paudel N, Pernia Marin M, Suy S, Collins SP, Barnes W, Collins BT. Stereotactic Body Radiation Therapy: A Versatile, Well-Tolerated, and Effective Treatment Option for Extracranial Metastases From Primary Ovarian and Uterine Cancer. Front Oncol 2020; 10:572564. [PMID: 33425723 PMCID: PMC7793788 DOI: 10.3389/fonc.2020.572564] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 09/23/2020] [Indexed: 12/25/2022] Open
Abstract
Purpose Single extracranial metastases from ovarian and uterine malignancies have historically been treated with surgery or conventional radiation. We report mature local control (LC), overall survival (OS), progression free survival (PFS), and toxicity for patients who completed 5-fraction stereotactic body radiation therapy (SBRT). Methods Patients with biopsy-proven, single extracranial metastases from primary ovarian and uterine malignancies treated with 5-fraction SBRT were included. Patients were stratified based on tumor volume (small < 50 cc or large ≥ 50 cc) and dose (low dose < 35 Gy or high ≥ 35 Gy). Kaplan–Meier method was used to estimate LC, OS, and PFS. Results Between July 2007 and July 2012, 20 patients underwent SBRT to a single extracranial metastasis. Primary site was divided evenly between ovarian and uterine (n = 10 each). Metastases involved the liver (30%), abdominal lymph nodes (25%), lung (20%), pelvic lymph nodes (10%), spine (10%), and extremity (5%). The median gross tumor volume (GTV) was 42.5 cc (range, 5–273 cc) and the median dose to the GTV was 35 Gy (range, 30–50 Gy). At a median follow-up of 56 months, the 5-year LC and OS estimates were 73 and 46%. When stratified by tumor volume, the 5-year LC and OS for small tumors were significantly better at 100% (p < 0.01) and 65% (p < 0.02). When stratified by dose, the 5-year LC was 87.5% with high dose and 53.6% with low dose (p = 0.035). The 5-year PFS for the entire cohort was 20%. Four patients with small metastases who had complete response remained disease free at study completion and were considered cured (median PFS > 10 years). Treatment was generally well tolerated, and only one patient experienced a late grade III musculoskeletal SBRT related toxicity. Conclusions SBRT is a versatile, well-tolerated, and effective treatment option for single extracranial metastases from ovarian and uterine primary tumors. 35 Gy in five fractions appears to be a practical minimum effective dose. Four patients with small metastases were disease free at the study completion and considered cured. However, patients with larger metastases (≥50 cc) may require higher SBRT dosing or alternative treatments.
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Affiliation(s)
- Nima Aghdam
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States.,Department of Radiation Oncology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States
| | - Michael C Repka
- Department of Radiation Oncology, New York University Winthrop Hospital, Mineola, NY, United States
| | - Mary McGunigal
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Abby Pepin
- School of Medicine and Health Sciences, George Washington University, Washington, DC, United States
| | - Ima Paydar
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, United States
| | - Sonali Rudra
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Nitika Paudel
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Monica Pernia Marin
- Geriatric and Palliative Medicine Division, George Washington University Hospital, Washington, DC, United States
| | - Simeng Suy
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Sean P Collins
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
| | - Willard Barnes
- Division of Gynecologic Oncology, Georgetown University Hospital, Washington, DC, United States
| | - Brian T Collins
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, United States
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12
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Aghdam N, McGunigal M, Wang H, Repka MC, Mete M, Fernandez S, Dash C, Al-Refaie WB, Unger KR. Ethnicity and insurance status predict metastatic disease presentation in prostate, breast, and non-small cell lung cancer. Cancer Med 2020; 9:5362-5380. [PMID: 32511873 PMCID: PMC7402826 DOI: 10.1002/cam4.3109] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 04/03/2020] [Accepted: 04/08/2020] [Indexed: 01/10/2023] Open
Abstract
Background Ethnicity and insurance status have been shown to impact odds of presenting with metastatic cancer, however, the interaction of these two predictors is not well understood. We evaluate the difference in odds of presenting with metastatic disease in minorities compared to white patients despite access to the same insurance across three common cancer types. Methods Using the National Cancer Database, a multilevel logistic regression model that estimated the odds of metastatic disease was fit, adjusting for covariates including year of diagnosis, ethnicity, insurance, income, and region. We included adults diagnosed with metastatic prostate, non–small cell lung cancer (NSCLC), and breast cancer from 2004 to 2015. Results The study cohort consisted of 1 191 241 prostate cancer (PCa), 1 310 986 breast cancer (BCa), and 1 183 029 NSCLC patients. Private insurance was the most protective factor against metastatic presentation. Odds of presenting with metastatic disease were 0.190 [95% CI, 0.182‐0.198], 0.616 [95% CI, 0.602‐0.630], and 0.270 [95% CI, 0.260‐0.279] for PCa, NSCLC, and BCa compared to uninsured patients, respectively. Private insurance provided the most significant benefit to non‐Hispanic White PCa patients with 81% reduction in odds of metastatic presentation and conferred the least benefit to African‐American NSCLC patients at 30.4% reduction in odds of metastatic presentation. Conclusions Insurance status provided the single most protective effect against metastatic presentation. This benefit varied for minorities despite similar insurance. Reducing metastatic disease presentation rates requires addressing social barriers to care independent of insurance.
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Affiliation(s)
- Nima Aghdam
- Department of Radiation Medicine, MedStar-Georgetown Hospital, Washington, DC, USA
| | - Mary McGunigal
- Department of Radiation Medicine, MedStar-Georgetown Hospital, Washington, DC, USA
| | - Haijun Wang
- MedStar Health Research Institute, Hyattsville, MD, USA
| | | | - Mihriye Mete
- MedStar Health Research Institute, Hyattsville, MD, USA
| | | | - Chiranjeev Dash
- Georgetown Lombardi Comprehensive Cancer Center, Office of Minority Health & Health Disparities Research, Washington, DC, USA
| | - Waddah B Al-Refaie
- MedStar-Georgetown Surgical Outcomes Research Center, Washington, DC, USA.,MedStar-Georgetown University Hospital, Washington, DC, USA
| | - Keith R Unger
- Department of Radiation Medicine, MedStar-Georgetown Hospital, Washington, DC, USA
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13
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Repka MC, Lei S, Campbell L, Suy S, Voyadzis JM, Kalhorn C, McGrail K, Jean W, Subramaniam DS, Lischalk JW, Collins SP, Collins BT. Long-Term Outcomes Following Conventionally Fractionated Stereotactic Boost for High-Grade Gliomas in Close Proximity to Critical Organs at Risk. Front Oncol 2018; 8:373. [PMID: 30254985 PMCID: PMC6141832 DOI: 10.3389/fonc.2018.00373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 08/21/2018] [Indexed: 11/18/2022] Open
Abstract
Purpose/Objective: High-grade glioma is the most common primary malignant tumor of the CNS, with death often resulting from uncontrollable intracranial disease. Radiation dose may be limited by the tolerance of critical structures, such as the brainstem and optic apparatus. In this report, long-term outcomes in patients treated with conventionally fractionated stereotactic boost for tumors in close proximity to critical structures are presented. Materials/Methods: Patients eligible for inclusion in this single institution retrospective review had a pathologically confirmed high-grade glioma status post-surgical resection. Inclusion criteria required tumor location within one centimeter of a critical structure, including the optic chiasm, optic nerve, and brainstem. Radiation therapy consisted of external beam radiation followed by a conventionally fractionated stereotactic boost. Oncologic outcomes and toxicity were assessed. Results: Thirty patients eligible for study inclusion underwent resection of a high-grade glioma. The median initial adjuvant EBRT dose was 50 Gy with a median conventionally fractionated stereotactic boost of 10 Gy. All stereotactic treatments were given in 2 Gy daily fractions. Median follow-up time for the entire cohort was 38 months with a median overall survival of 45 months and 5-year overall survival of 32.5%. The median freedom from local progression was 45 months, and the 5-year freedom from local progression was 29.7%. Two cases of radiation retinopathy were identified following treatment. No patient experienced toxicity attributable to the optic chiasm, optic nerve, or brainstem and no grade 3+ radionecrosis was observed. Conclusions: Oncologic and toxicity outcomes in high-grade glioma patients with tumors in unfavorable locations treated with conventionally fractionated stereotactic boost are comparable to those reported in the literature. This treatment strategy is appropriate for those patients with resected high-grade glioma in close proximity to critical structures.
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Affiliation(s)
- Michael C Repka
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Siyuan Lei
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Lloyd Campbell
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Simeng Suy
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Jean-Marc Voyadzis
- Department of Neurosurgery, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Christopher Kalhorn
- Department of Neurosurgery, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Kevin McGrail
- Department of Neurosurgery, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Walter Jean
- Department of Neurological Surgery, George Washington University Hospital, Washington, DC, United States
| | - Deepa S Subramaniam
- Division of Hematology and Oncology, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Jonathan W Lischalk
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Sean P Collins
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
| | - Brian T Collins
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, United States
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14
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Lischalk JW, Chen H, Repka MC, Campbell LD, Obayomi-Davies O, Kataria S, Kole TP, Rudra S, Collins BT. Definitive hypofractionated radiation therapy for early stage breast cancer: Dosimetric feasibility of stereotactic ablative radiotherapy and proton beam therapy for intact breast tumors. Adv Radiat Oncol 2018; 3:447-457. [PMID: 30202812 PMCID: PMC6128030 DOI: 10.1016/j.adro.2018.05.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/18/2018] [Accepted: 05/10/2018] [Indexed: 12/31/2022] Open
Abstract
Purpose Few definitive treatment options exist for elderly patients diagnosed with early stage breast cancer who are medically inoperable or refuse surgery. Historical data suggest very poor local control with hormone therapy alone. We examined the dosimetric feasibility of hypofractionated radiation therapy using stereotactic ablative radiotherapy (SABR) and proton beam therapy (PBT) as a means of definitive treatment for early stage breast cancer. Methods and Materials Fifteen patients with biopsy-proven early stage breast cancer with a clinically visible tumor on preoperative computed tomography scans were identified. Gross tumor volumes were contoured and correlated with known biopsy-proven malignancy on prior imaging. Treatment margins were created on the basis of set-up uncertainty and image guidance capabilities of the three radiation modalities analyzed (3-dimensional conformal radiation therapy [3D-CRT], SABR, and PBT) to deliver a total dose of 50 Gy in 5 fractions. Dose volume histograms were analyzed and compared between treatment techniques. Results The median planning target volume (PTV) for SABR, PBT, and 3-dimensional CRT was 11.91, 21.03, and 45.08 cm3, respectively, and were significantly different (P < .0001) between treatment modalities. Overall target coverage of gross tumor and clinical target volumes was excellent with all three modalities. Both SABR and PBT demonstrated significant dosimetric improvements, each in its own unique manner, relative to 3D-CRT. Dose constraints to normal structures including ipsilateral/contralateral breast, bilateral lungs, and heart were all consistently achieved using SABR and PBT. However, skin or chest wall dose constraints were exceeded in some cases for both SABR and PBT plans and was dictated by the anatomic location of the tumor. Conclusions Definitive hypofractionated radiation therapy using SABR and PBT appears to be dosimetrically feasible for the treatment of early stage breast cancer. The anatomical location of the tumor relative to the skin and chest wall appears to be the primary limiting dosimetric factor.
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Affiliation(s)
- Jonathan W Lischalk
- Department of Radiation Medicine, Georgetown University Hospital, Washington, District of Columbia
| | - Hao Chen
- Department of Radiation Medicine, Georgetown University Hospital, Washington, District of Columbia
| | - Michael C Repka
- Department of Radiation Medicine, Georgetown University Hospital, Washington, District of Columbia
| | - Lloyd D Campbell
- Department of Radiation Medicine, Georgetown University Hospital, Washington, District of Columbia
| | - Olusola Obayomi-Davies
- Department of Radiation Medicine, Georgetown University Hospital, Washington, District of Columbia
| | - Shaan Kataria
- Department of Radiation Medicine, Georgetown University Hospital, Washington, District of Columbia
| | - Thomas P Kole
- Department of Radiation Medicine, Georgetown University Hospital, Washington, District of Columbia
| | - Sonali Rudra
- Department of Radiation Medicine, Georgetown University Hospital, Washington, District of Columbia
| | - Brian T Collins
- Department of Radiation Medicine, Georgetown University Hospital, Washington, District of Columbia
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15
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Repka MC, Aghdam N, Karlin AW, Unger KR. Social determinants of stage IV anal cancer and the impact of pelvic radiotherapy in the metastatic setting. Cancer Med 2017; 6:2497-2506. [PMID: 28980407 PMCID: PMC5673908 DOI: 10.1002/cam4.1203] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 07/19/2017] [Accepted: 07/20/2017] [Indexed: 11/19/2022] Open
Abstract
Anal cancer is a relatively rare malignancy, and a minority of patients present with metastatic disease in the United States. The National Cancer Database (NCDB) was used to identify factors associated with metastatic disease at presentation and evaluate the role of pelvic radiotherapy in these patients. The NCDB was queried for patients with squamous cell cancer of the anus diagnosed between 2004 and 2013. Patients were stratified by clinical stage at diagnosis, and a binary logistic regression model was created to identify factors associated with metastatic disease at diagnosis. A secondary metastatic cohort was generated and a multivariable Cox proportional hazards model was created to identify factors associated with improved survival. To validate findings, propensity-score matching was performed to generate a 1:1 paired dataset stratified by receipt of pelvic radiotherapy. The primary analysis cohort consisted of 28,500 patients. Facility location, male gender, and lack of insurance were confirmed as independent risk factors for metastatic disease. The metastatic cohort consisted of 1264 patients. Multivariable analysis confirmed female sex, possession of a private or Medicare insurance plan, pelvic radiotherapy, and chemotherapy as independent predictors of improved survival. A propensity-score matched cohort of 730 patients was generated. The median survival was 17.6 months in patients who received radiotherapy versus 14.5 months in those who did not (P < 0.01). In this cohort, male gender and lack of insurance were associated with metastatic disease at presentation. Furthermore, a significant benefit was associated with the use of pelvic radiotherapy. Future prospective research is warranted to confirm these findings.
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Affiliation(s)
- Michael C. Repka
- Department of Radiation MedicineGeorgetown University HospitalWashingtonWashington DC
| | - Nima Aghdam
- Department of Radiation MedicineGeorgetown University HospitalWashingtonWashington DC
| | - Andrew W. Karlin
- Department of Radiation MedicineGeorgetown University HospitalWashingtonWashington DC
| | - Keith R. Unger
- Department of Radiation MedicineGeorgetown University HospitalWashingtonWashington DC
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16
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Repka MC, Kole TP, Lee J, Wu B, Lei S, Yung T, Collins BT, Suy S, Dritschilo A, Lynch JH, Collins SP. Predictors of acute urinary symptom flare following stereotactic body radiation therapy (SBRT) in the definitive treatment of localized prostate cancer. Acta Oncol 2017; 56:1136-1138. [PMID: 28270015 DOI: 10.1080/0284186x.2017.1299221] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Michael C. Repka
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
| | - Thomas P. Kole
- Department of Radiation Oncology, The Valley Health Hospital, Ridgewood, NJ, USA
| | - Jacqueline Lee
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
| | - Binbin Wu
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Siyuan Lei
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
| | - Thomas Yung
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
| | - Brian T. Collins
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
| | - Simeng Suy
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
| | - Anatoly Dritschilo
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
| | - John H. Lynch
- Department of Urology, Georgetown University Hospital, Washington, DC, USA
| | - Sean P. Collins
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
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17
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Abstract
Hepatobiliary malignancies represent a heterogeneous group of diseases, which often arise in a background of underlying hepatic dysfunction complicating their local management. Surgical resection continues to be the standard of care for hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC); unfortunately the majority of patients are inoperable at presentation. The aggressiveness of these lesions makes locoregional control of particular importance. Historical experience with less sophisticated radiotherapy resulted in underwhelming efficacy and oftentimes prohibitive liver toxicity. However, with the advent of extremely conformal and precise radiotherapy delivery, dose escalation to the tumor with sparing of surrounding normal tissue has yielded notable improvements in efficacy for this modality of treatment. Dose escalation has come in a variety of forms most notably as stereotactic body radiation therapy (SBRT) and hypofractionated proton therapy. As radiation techniques continue to improve, their proper incorporation into the local management of hepatobiliary malignancies will be paramount in improving the prognosis of what is a grave diagnosis.
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Affiliation(s)
- Jonathan W Lischalk
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
| | - Michael C Repka
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
| | - Keith Unger
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC, USA
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18
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Bernhardt D, Adeberg S, Bozorgmehr F, Opfermann N, Hoerner-Rieber J, Repka MC, Kappes J, Thomas M, Bischoff H, Herth F, Heußel CP, Debus J, Steins M, Rieken S. Nine-year Experience: Prophylactic Cranial Irradiation in Extensive Disease Small-cell Lung Cancer. Clin Lung Cancer 2016; 18:e267-e271. [PMID: 28027850 DOI: 10.1016/j.cllc.2016.11.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 11/15/2016] [Accepted: 11/22/2016] [Indexed: 10/20/2022]
Abstract
BACKGROUND In 2007, the European Organization for Research and Treatment of Cancer (EORTC) study (ClinicalTrials.gov identifier, NCT00016211) demonstrated a beneficial effect on overall survival (OS) with the use of prophylactic cranial irradiation (PCI) for extensive disease (ED) small-cell lung cancer (SCLC). Nevertheless, debate is ongoing regarding the role of PCI, because the patients in that trial did not undergo magnetic resonance imaging (MRI) of the brain before treatment. Also, a recent Japanese randomized trial showed a detrimental effect of PCI on OS in patients with negative pretreatment brain MRI findings. MATERIALS AND METHODS We examined the medical records of 136 patients with ED SCLC who had initially responded to chemotherapy and undergone PCI from 2007 to 2015. The outcomes, radiation toxicity, neurologic progression-free survival, and OS after PCI were analyzed. Survival and correlations were calculated using log-rank and univariate Cox proportional hazard ratio analyses. RESULTS The median OS and the median neurologic progression-free survival after PCI was 12 and 19 months, respectively. No significant survival difference was seen for patients who had undergone MRI before PCI compared with patients who had undergone contrast-enhanced computed tomography (P = .20). Univariate analysis for OS did not show a statistically significant effect for known cofactors. CONCLUSION In the present cohort, PCI was associated with improved survival compared with the PCI arm of the EORTC trial, with a nearly doubled median OS period. Also, the median OS was prolonged by 2 months compared with the irradiation arm of the Japanese trial.
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Affiliation(s)
- Denise Bernhardt
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Heidelberg, Germany; Heidelberg Ion-Beam Therapy Center, Heidelberg, Germany.
| | - Sebastian Adeberg
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Heidelberg, Germany; Heidelberg Ion-Beam Therapy Center, Heidelberg, Germany; Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center, Heidelberg, Germany
| | - Farastuk Bozorgmehr
- Department of Thoracic Oncology, Thoraxklinik, Heidelberg University, Heidelberg Translational Lung Research Centre, Heidelberg, Germany; German Centre for Lung Research, Heidelberg, Germany
| | - Nils Opfermann
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Heidelberg, Germany
| | - Juliane Hoerner-Rieber
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Heidelberg, Germany
| | - Michael C Repka
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC
| | - Jutta Kappes
- Department of Pneumology, Thoraxklinik, Heidelberg University, Heidelberg, Germany
| | - Michael Thomas
- Department of Thoracic Oncology, Thoraxklinik, Heidelberg University, Heidelberg Translational Lung Research Centre, Heidelberg, Germany; German Centre for Lung Research, Heidelberg, Germany
| | - Helge Bischoff
- Department of Thoracic Oncology, Thoraxklinik, Heidelberg University, Heidelberg Translational Lung Research Centre, Heidelberg, Germany; German Centre for Lung Research, Heidelberg, Germany
| | - Felix Herth
- German Centre for Lung Research, Heidelberg, Germany; Department of Pneumology, Thoraxklinik, Heidelberg University, Heidelberg, Germany
| | - Claus Peter Heußel
- German Centre for Lung Research, Heidelberg, Germany; Diagnostic and Interventional Radiology With Nuclear Medicine, Thoraxklinik, University of Heidelberg, Heidelberg, Germany; Department of Diagnostic and Interventional Radiology, University of Heidelberg, Heidelberg, Germany
| | - Jürgen Debus
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Heidelberg, Germany; Heidelberg Ion-Beam Therapy Center, Heidelberg, Germany; Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center, Heidelberg, Germany
| | - Martin Steins
- Department of Thoracic Oncology, Thoraxklinik, Heidelberg University, Heidelberg Translational Lung Research Centre, Heidelberg, Germany; German Centre for Lung Research, Heidelberg, Germany
| | - Stefan Rieken
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany; Heidelberg Institute of Radiation Oncology, Heidelberg, Germany
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Lischalk JW, König L, Repka MC, Uhl M, Dritschilo A, Herfarth K, Debus J. From Röntgen Rays to Carbon Ion Therapy: The Evolution of Modern Radiation Oncology in Germany. Int J Radiat Oncol Biol Phys 2016; 96:729-735. [PMID: 27788946 DOI: 10.1016/j.ijrobp.2016.08.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 08/22/2016] [Indexed: 10/21/2022]
Affiliation(s)
- Jonathan W Lischalk
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC.
| | - Laila König
- Department of Radiation Oncology, University Hospital of Heidelberg, Heidelberg, Germany
| | - Michael C Repka
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC
| | - Matthias Uhl
- Department of Radiation Oncology, University Hospital of Heidelberg, Heidelberg, Germany
| | - Anatoly Dritschilo
- Department of Radiation Medicine, Georgetown University Hospital, Washington, DC
| | - Klaus Herfarth
- Department of Radiation Oncology, University Hospital of Heidelberg, Heidelberg, Germany
| | - Jürgen Debus
- Department of Radiation Oncology, University Hospital of Heidelberg, Heidelberg, Germany
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20
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Lischalk JW, Woo SM, Kataria S, Aghdam N, Paydar I, Repka MC, Anderson ED, Collins BT. Long-term outcomes of stereotactic body radiation therapy (SBRT) with fiducial tracking for inoperable stage I non-small cell lung cancer (NSCLC). ACTA ACUST UNITED AC 2016; 5:379-387. [PMID: 28018523 PMCID: PMC5149392 DOI: 10.1007/s13566-016-0273-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 08/10/2016] [Indexed: 12/25/2022]
Abstract
Background Stereotactic body radiation therapy (SBRT) for stage I non-small cell lung cancer (NSCLC) is considered standard of care in the medically inoperable patient population. Multiple methods of SBRT delivery exist including fiducial-based tumor tracking, which allows for smaller treatment margins and avoidance of patient immobilization devices. We explore the long-term clinical outcomes of this novel fiducial-based SBRT method. Methods In this single institutional retrospective review, we detail the outcomes of medically inoperable pathologically confirmed stage I NSCLC. Patients were treated with the Cyberknife SBRT system using a planning target volume (PTV) defined as a 5-mm expansion from gross tumor volume (GTV) without creation of an internal target volume (ITV). Dose was delivered in three or five equal fractions of 10 to 20 Gy. Pretreatment and posttreatment pulmonary function test (PFT) changes and evidence of late radiological rib fractures were analyzed for the majority of patients. Actuarial local control, locoregional control, distant control, and overall survival were calculated using the Kaplan-Meier method. Results Sixty-one patients with a median age of 75 years were available for analysis. The majority (80 %) of patients were deemed to be medically inoperable due to underlying pulmonary dysfunction. Eleven patients (18 %) developed symptomatic pneumothoraces secondary to fiducial placement under CT guidance, which precipitously dropped to 0 % following transition to bronchoscopic fiducial placement. The 2-year rib fracture risk was 21.4 % with a median time to rib fracture of 2.9 years. PFTs averaged over all patients and parameters demonstrated small absolute declines, 5.7 % averaged PFT decline, at approximately 1 year of follow-up, but only the diffusing capacity of lung for carbon monoxide (DLCO) demonstrated a statistically significant decline (10.29 vs. 9.01 mL/min/mmHg, p = 0.01). Five-year local control, locoregional control, and overall survival were 87.6, 71.8, and 39.3 %, respectively. Conclusions Despite reduced treatment margins and lack of patient immobilization, SBRT with fiducial-based tumor tracking achieves clinically comparable long-term outcomes to other linac-based SBRT approaches.
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Affiliation(s)
- Jonathan W Lischalk
- Department of Radiation Medicine, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, N.W, Washington, DC 20007 USA
| | - Stephanie M Woo
- Department of Radiation Medicine, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, N.W, Washington, DC 20007 USA
| | - Shaan Kataria
- Department of Radiation Medicine, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, N.W, Washington, DC 20007 USA
| | - Nima Aghdam
- Department of Radiation Medicine, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, N.W, Washington, DC 20007 USA
| | - Ima Paydar
- Department of Radiation Medicine, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, N.W, Washington, DC 20007 USA
| | - Michael C Repka
- Department of Radiation Medicine, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, N.W, Washington, DC 20007 USA
| | - Eric D Anderson
- Division of Pulmonary, Critical Care, and Sleep Medicine, Georgetown University Hospital, Pasquerilla Healthcare Center, 5th floor, 3800 Reservoir Road, N.W., Washington, DC 20007 USA
| | - Brian T Collins
- Department of Radiation Medicine, Georgetown University Hospital, Lower Level Bles, 3800 Reservoir Road, N.W, Washington, DC 20007 USA
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21
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Repka MC, Guleria S, Cyr RA, Yung TM, Koneru H, Chen LN, Lei S, Collins BT, Krishnan P, Suy S, Dritschilo A, Lynch J, Collins SP. Acute Urinary Morbidity Following Stereotactic Body Radiation Therapy for Prostate Cancer with Prophylactic Alpha-Adrenergic Antagonist and Urethral Dose Reduction. Front Oncol 2016; 6:122. [PMID: 27242962 PMCID: PMC4870496 DOI: 10.3389/fonc.2016.00122] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 05/02/2016] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Stereotactic body radiation therapy (SBRT) delivers high doses of radiation to the prostate while minimizing radiation to the adjacent critical organs. Large fraction sizes may increase urinary morbidity due to unavoidable treatment of the prostatic urethra. This study reports rates of acute urinary morbidity following SBRT for localized prostate cancer with prophylactic alpha-adrenergic antagonist utilization and urethral dose reduction (UDR). METHODS From April 2013 to September 2014, 102 patients with clinically localized prostate cancer were treated with robotic SBRT to a total dose of 35-36.25 Gy in five fractions. UDR was employed to limit the maximum point dose of the prostatic urethra to 40 Gy. Prophylactic alpha-adrenergic antagonists were initiated 5 days prior to SBRT and continued until resolution of urinary symptoms. Quality of life (QoL) was assessed before and after treatment using the American Urological Association Symptom Score (AUA) and the Expanded Prostate Cancer Index Composite-26 (EPIC-26). Clinical significance was assessed using a minimally important difference (MID) of one half SD change from baseline. RESULTS One hundred two patients underwent definitive prostate SBRT with UDR and were followed for 3 months. No patient experienced acute urinary retention requiring catheterization. A mean baseline AUA symptom score of 9.06 significantly increased to 11.83 1-week post-SBRT (p = 0.0024) and 11.84 1-month post-SBRT (p = 0.0023) but returned to baseline by 3 months. A mean baseline EPIC-26 irritative/obstructive score of 87.7 decreased to 74.1 1-week post-SBRT (p < 0.0001) and 77.8 1-month post-SBRT (p < 0.0001) but returned to baseline at 3 months. EPIC-26 irritative/obstructive score changes were clinically significant, exceeding the MID of 6.0. At baseline, 8.9% of men described their urinary function as a moderate to big problem, and that proportion increased to 37.6% 1 week following completion of SBRT before returning to baseline by 3 months. CONCLUSION Stereotactic body radiation therapy for localized prostate cancer with utilization of prophylactic alpha-adrenergic antagonist and UDR was well tolerated as determined by acute urinary function and bother, and symptoms were comparable to those observed following conventionally fractionated external beam radiation therapy (EBRT). Longer follow-up is required to assess long-term toxicity and efficacy following SBRT with UDR.
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Affiliation(s)
- Michael C. Repka
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Shan Guleria
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Robyn A. Cyr
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Thomas M. Yung
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Harsha Koneru
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Leonard N. Chen
- Department of Pathology, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Siyuan Lei
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Brian T. Collins
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Pranay Krishnan
- Department of Radiology, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Simeng Suy
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Anatoly Dritschilo
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
| | - John Lynch
- Department of Urology, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Sean P. Collins
- Department of Radiation Medicine, MedStar Georgetown University Hospital, Washington, DC, USA
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