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Lo, Simon S.

https://orcid.org/0000-0002-3744-4065

Mayo Clinic

University of Washington

Citations 8

ACR–ARS Practice Parameter for Image-Guided Radiation Therapy (IGRT)
Garsa, Adam , Buckey, C, Freedman, Laura , Gros, Sebastien , Hallemeier, Christopher L. , Lo, Simon S. , Milano, Michael T. , Saeed, Hina , Ye, Jason C. , Schechter, Naomi R., Buckey, Courtney R, Davis, Brian J. , Hallemeier, Christopher Leigh , Small, William

American Journal of Clinical Oncology | June 20, 2025 | Volume: 48 | Issue: 11 | Pages: 529-539

10.1097/coc.0000000000001220 Get It

Objectives: This practice parameter was revised collaboratively by the American College of Radiology (ACR), and American Radium Society (ARS). Image-guided radiation therapy (IGRT) uses various imaging modalities to maximize the accuracy and precision of radiation treatment delivery. Methods: This practice parameter was developed according to the process described under the heading The Process for Developing ACR Practice Parameters and Technical Standards on the ACR website (https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards) by the Committee on Practice Parameters–Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with the ARS. Results: This practice parameter for IGRT addresses qualifications and responsibilities of personnel, clinical IGRT implementation, documentation, quality control and improvement, safety, and patient education. Since the publication of the ACR–ASTRO Practice Parameter in 2019, there is now more clarity as to what criteria and parameters need to be documented in the medical record, a better appreciation of the large amount of imaging data, how to interpret such data, as well as the complex interactions of multiple systems in the implementation of IGRT. Conclusions: This practice parameter assists practitioners in the clinical use of IGRT. IGRT should complement and be used in combination with other quality assurance processes. IGRT is a rapidly evolving field, and practitioners should have a thorough understanding of its strengths and potential limitations.
Immune Subtyping Identifies Patients With Hormone Receptor–Positive Early-Stage Breast Cancer Who Respond to Neoadjuvant Immunotherapy (IO): Results From Five IO Arms of the I-SPY2 Trial
Wolf, Denise M. , Yau, Christina , Glas, Annuska M. , Barcaru, Andrei, Kuilman, Midas M. , Swigart, Lamorna Brown , Hirst, Gillian L. , Basu, A. , Magbanua, Mark Jesus M. , Sayaman, Rosalyn W. , Huppert, Laura A. , Investigators, I-SPY2, Borowsky, Alexander D. , Pohlmann, Paula R. , Clark, Amy S. , Yee, Douglas , Perlmutter, Jane , Petricoin, Emanuel F. , Chien, A. Jo , Stringer-Reasor, Erica , Liu, Minetta C. , Nanda, Rita , Veer, Laura van ‘t , Melisko, Michelle , Albain, Kathy S. , Robinson, Patricia A. , Lo, Simon S. , Potter, David J. , Beckwith, Heather , Haddad, Tufia C. , Kemmer, Kathleen, Lu, Janice , Williams, Nicole , Ellis, Erin D. , Sanford, Amy, Sanft, Tara, Viscusi, Rebecca K., Arora, Mili, Northfelt, Donald W. , Haley, Barbara , Yung, Rachel L. , Mayer, Ingrid, Khan, Qamar J. , Edmiston, Kirsten K., Glas, Annuska , Mittempergher, Lorenza , Brown-Swigart, Lamorna , Hirst, Gillian L , Basu, Amrita , Magbanua, Mark J M , Sayaman, Rosalyn , Huppert, Laura , Delson, Amy , Symmans, W Fraser , Pohlmann, Paula , Rugo, Hope S , Clark, Amy S , Yee, Douglas , DeMichele, Angela , Petricoin, Emmanuel F , Chien, Jo , Stringer-Reasor, Erica , Shatsky, Rebecca , Liu, Minetta , Soliman, Hatem Hussein , Isaacs, Claudine , Nanda, Rita , Hylton, Nola M. , Pusztai, Lajos , Esserman, Laura J , Veer, Laura J. van’t , Campbell, Michael, Investigators, I-SPY2, Symmans, W. Fraser , Rugo, Hope S. , DeMichele, Angela , Shatsky, Rebecca , Han, Hyo S , Isaacs, Claudine , Pusztai, Lajos , Esserman, Laura J. , Mukhtar, Rita A. , Wallace, Anne M. , Yeung, Kay T. , Olopade, Olufunmilayo I. , Potter, David, Blaes, Anne , Boughey, Judy C. , Elias, Anthony , Mitri, Zahi Ibrahim , Lang, Julie E. , Thomas, Alexandra , Trivedi, Meghna S. , Hershman, Dawn L. , Meisel, Jane Lowe , Kalinsky, Kevin M. , Vaklavas, Christos , Sanft, Tara , Arora, Mili, Falkson, Carla I. , Murthy, Rashmi Krishna

JCO Precision Oncology | June 17, 2025 | Volume: No volume available | Issue: 9 | Pages: No page available

10.1200/po-24-00776 Get It

PURPOSE Neoadjuvant immunotherapy (IO) has become the standard of care for early-stage triple-negative breast cancer (TNBC), but not yet for other subtypes. We previously developed a clinical-grade mRNA-based immune classifier (ImPrint) predicting response to IO that is now being used in I-SPY2.2 as part of the response predictive subtypes. We report the performance of ImPrint in hormone receptor–positive and human epidermal growth factor receptor 2–negative (HR+HER2–) patients from five IO arms. METHODS A total of 204 HR+HER2– (MammaPrint high-risk) patients from five IO arms (anti–PD-1, anti–PD-L1/poly [ADP-ribose] polymerase inhibitor combination, anti–PD-1/toll-like receptor 9 dual-IO combination, and anti–PD-1 ± lymphocyte activation gene 3 dual-IO combination) and 191 patients from the chemotherapy-only control arm were included in this analysis. Patients were classified as ImPrint+ (likely sensitive) versus ImPrint– (likely resistant), using pretreatment mRNA. Performance of ImPrint for predicting pathologic complete response (pCR) to IO-containing arms was characterized and compared with tumor grade (III), MammaPrint (ultra) High2 risk (MP2), and estrogen receptor (ER)-low (ER ≤ 10%). RESULTS Overall, the pCR rate across the five IO arms was 33%. 26% of HR+HER2– patients were ImPrint+, and pCR rates with IO were 75% in ImPrint+ versus 17% in ImPrint–, with the highest pCR rate >90% in a dual-IO arm. In the control arm, pCR rates were 33% in ImPrint+ and 8% in ImPrint–. Tumor grade (III), MP2, and ER-low showed pCR rates in IO of 45%, 56%, and 63%, respectively, with lower pCR odds ratios (OR < 7.5) compared with ImPrint (OR = 14.5). CONCLUSION Using an accurate selection strategy, HR+HER2– patients could achieve pCR rates similar to what is seen with best neoadjuvant therapies in TNBC and HER2+ (ie, pCR rate >65%-70%). ImPrint, an Food and Drug Administration IDE-enabled assay, may represent a way to identify HR+HER2– patients for IO that best balances likely benefit versus risk of serious immune-related adverse events.
Abstract P2-14-01: The impact of local therapy on locoregional recurrence in women with high risk breast cancer in the neoadjuvant I-SPY2 TRIAL
Suleiman, Linda I. , Price, ER, Singhrao, Ruby , Albain, KS, Chien, AJ, Forero‐Torres, Andres , Wallace, AM, Ellis, ED, Elias, AD, Lang, JE, Lu, Jinghui , Han, HS, Clark, AS, Korde, LA, Nanda, Rita , Northfelt, DW, Khan, QJ, Viscusi, RK, Euhus, DM, Edmiston, KK, Chui, SY, Kemmer, KA, Wood, WC, Liu, MC, Olopade, OI, Leyland-Jones, B, Moulder, SL, Rugo, HS, Schwab, Richard B. , Lo, Simon S. , Beckwith, Heather , Berry, DA, Asare, SM, Esserman, LJ, Boughey, JC , Mukhtar, RA, Khan, Qamar J. , Silverstein, J, Suleiman, L, Yau, Christina , Price, Erin, Yee, Douglas , DeMichele, Angela , Isaacs, Claudine , Pusztai, Lajos , Park, JW, Tripathy, Debu , Helsten, Teresa L.

Cancer Research | May 11, 2019 | Volume: 79 | Issue: 4_Supplement | Pages: P2-14-01-P2-14-01

10.1158/1538-7445.sabcs18-p2-14-01 Get It

Abstract Background: In women with breast cancer receiving neoadjuvant chemotherapy, residual cancer burden (RCB) predicts distant recurrence and survival. In those with high risk tumors, locoregional recurrence (LRR) remains a concern, and has been associated with type of local therapy received. We evaluated the impact of local therapy on LRR in the ISPY-2 TRIAL. Methods: Data were analyzed in Stata 14.2, using Chi2 test, log rank test, and a Cox proportional hazards model. RCB was considered a categorical variable (0/1 versus 2/3), as described in prior publications. Breast surgery categories were lumpectomy +/- radiotherapy, or mastectomy +/- radiotherapy. Axillary surgery was defined as sentinel lymph node (SLN) surgery (≤6 nodes removed) or axillary dissection (&gt;6 nodes). Results: Follow up data from the I-SPY2 TRIAL were available for 630 patients (median follow up 2.76 yrs, range 0.4-7.2). Type of local therapy was significantly associated with clinical stage at presentation, with stage III patients most frequently undergoing mastectomy + radiation (p&lt;0.001). Women with higher RCB were more likely to undergo mastectomy than those with lower RCB (61.3% vs 48.8% mastectomy rate, p=0.002), and more likely to receive adjuvant radiotherapy (62.0% vs 53.9%, p=0.048). There was no association between clinical stage, type of surgery, or radiotherapy and LRR (Table). Higher RCB was significantly associated with LRR, with 3 year locoregional recurrence free rate of 95.1% in RCB 0/1 versus 89.9% in RCB 2/3 (p=0.003). In a Cox model adjusting for clinical stage, tumor subtype, surgical therapy, RCB status, nodal radiation, and age, significant predictors for LRR were tumor subtype and RCB status. Hazard ratio (HR) for LRR in those with RCB 0/1 was 0.39 compared to those with RCB 2/3 (95% CI 0.17-0.87, p=0.021). There was no difference in LRR between breast conservation and mastectomy; within the breast conservation group, those who had lumpectomy alone had higher hazard of LRR compared to those having lumpectomy + radiation (HR 3.1, 95% CI 1.1-9.2, p=0.043). Conclusions: Extent of surgical therapy was not associated with local tumor control, regardless of advanced tumor stage at presentation. Rather, tumor biology and response to therapy were the best predictors of LRR. These data highlight the opportunity to minimize the morbidity of extensive surgical therapy for patients with excellent response to systemic therapy. LRR rates by clinical features and treatment status FrequencyLRR RateP valueClinical Stage 0.5I240 (47.5%)5.8% II185 (36.6%)8.7% III80 (15.8%)6.3% Tumor Subtype 0.014ER+PR+Her2-161 (26.4%)3.1% ER+PR-Her2-56 (9.2%)3.6% Her2+176 (28.9%)6.3% Triple negative216 (35.5%)11.1% Local therapy 0.169Lumpectomy85 (13.5%)11.8% Lumpectomy with radiation198 (31.4%)5.6% Mastectomy173 (27.5%)5.2% Mastectomy with radiation174 (27.6%)8.6% Axillary surgery 0.23None5 (0.8%)20% SLN329 (52.2%)5.8% ALND296 (47%)8.5% Axillary radiation 0.535Yes42 (6.7%)9.5% No588 (93.3%)7.0% Axillary management 0.2No surgery or radiation5 (0.8%)20.0% SLN312 (50%)5.3% SLN+Axillary radiation17 (2.7%)8.3% ALND271 (43%)10.3% ALND+Axillary radiation25 (4%)5.4% RCB 0.0020/1293 (50.1%)3.8% 2/3292 (49.9%)10.3% Citation Format: Silverstein J, Suleiman L, Yau C, Price ER, Singhrao R, Yee D, DeMichele A, Isaacs C, Albain KS, Chien AJ, Forero-Torres A, Wallace AM, Pusztai L, Ellis ED, Elias AD, Lang JE, Lu J, Han HS, Clark AS, Korde L, Nanda R, Northfelt DW, Khan QJ, Viscusi RK, Euhus DM, Edmiston KK, Chui SY, Kemmer K, Wood WC, Park JW, Liu MC, Olopade O, Leyland-Jones B, Tripathy D, Moulder SL, Rugo HS, Schwab R, Lo S, Helsten T, Beckwith H, I-SPY 2 TRIAL Consortium, Berry DA, Asare SM, Esserman LJ, Boughey JC, Mukhtar RA. The impact of local therapy on locoregional recurrence in women with high risk breast cancer in the neoadjuvant I-SPY2 TRIAL [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-14-01.
Updates in the management of intradural spinal cord tumors: a radiation oncology focus
Kotecha, Rupesh , Chang, Eric L. , Brown, Paul D. , Lo, Simon S. , Samawi, Haider , Keith, Julia , Perry, James , Sahgal, Arjun , Mehta, Minesh P. , Suh, John H. , Das, Sunit

Neuro-Oncology | January 14, 2019 | Volume: 21 | Issue: 6 | Pages: 707-718

10.1093/neuonc/noz014 Get It

Abstract Primary spinal cord tumors represent a hetereogeneous group of central nervous system malignancies whose management is complex given the relatively uncommon nature of the disease and variety of tumor subtypes, functional neurologic deficits from the tumor, and potential morbidities associated with definitive treatment. Advances in neuroimaging; integration of diagnostic, prognostic, and predictive molecular testing into tumor classification; and developments in neurosurgical techniques have refined the current role of radiotherapy in the multimodal management of patients with primary spinal cord tumors, and corroborated the need for prospective, multidisciplinary discussion and treatment decision making. Radiotherapeutic technological advances have dramatically improved the entire continuum from treatment planning to treatment delivery, and the development of stereotactic radiosurgery and proton radiotherapy provides new radiotherapy options for patients treated in the definitive, adjuvant, or salvage setting. The objective of this comprehensive review is to provide a contemporary overview of the management of primary intradural spinal cord tumors, with a focus on radiotherapy.
Postoperative stereotactic radiosurgery for limited brain metastases: are we ready for prime time?
Lo, Simon S. , Brown, Paul D. , Foote, Matthew , Chao, Samuel T. , Chang, Eric L. , Sahgal, Arjun

Expert Review of Anticancer Therapy | July 24, 2017 | Volume: 17 | Issue: 9 | Pages: 775-777

10.1080/14737140.2017.1358090 Get It

Survey of Current Practices from the International Stereotactic Body Radiotherapy Consortium (Isbrtc) for Head and Neck Cancers
Karam, Irene , Yao, Min , Heron, Dwight E. , Poon, Ian , Koyfman, Shlomo A. , Yom, Sue S. , Siddiqui, Farzan , Lartigau, Éric, Cengiz, Mustafa , Yamazaki, Hideya , Hara, Wendy, Phan, Jack , Vargo, John A. , Lee, Victor , Foote, Robert L. , Harter, K. William, Lee, Nancy Y. , Sahgal, Arjun , Lo, Simon S. , Yom, Sue S , Phan, Jack

Future Oncology | November 15, 2016 | Volume: 13 | Issue: 7 | Pages: 603-613

10.2217/fon-2016-0403 Get It

ACR Appropriateness Criteria ® Metastatic Epidural Spinal Cord Compression and Recurrent Spinal Metastasis
Metastases:, Expert Panel on Radiation Oncology–Bone, Lo, Simon S. , Ryu, Samuel , Chang, Eric L. , Galanopoulos, Nicholas, Kim, Edward Y. , Kubicky, Charlotte Dai, Lee, Charles P., Rose, Peter S. , Sahgal, Arjun , Sloan, Andrew E. , Traughber, Bryan , Poznak, Catherine Van , Vassil, Andrew D. , Metastases:, Expert Panel on Radiation Oncology–Bone, Jones, Joshua , Teh, Bin Sing

Journal of Palliative Medicine | May 14, 2015 | Volume: 18 | Issue: 7 | Pages: 573-584

10.1089/jpm.2015.28999.sml Get It

Abstract Metastatic epidural spinal cord compression (MESCC) is an oncologic emergency and if left untreated, permanent paralysis will ensue. The treatment of MESCC is governed by disease, patient, and treatment factors. Patient's preferences and goals of care are to be weighed into the treatment plan. Ideally, a patient with MESCC is evaluated by an interdisciplinary team promptly to determine the urgency of the clinical scenario. Treatment recommendations must take into consideration the risk-benefit profiles of surgical intervention and radiotherapy for the particular individual's circumstance, including neurologic status, performance status, extent of epidural disease, stability of the spine, extra-spinal disease status, and life expectancy. In patients with high spinal instability neoplastic score (SINS) or retropulsion of bone fragments in the spinal canal, surgical intervention should be strongly considered. The rate of development of motor deficits from spinal cord compression may be a prognostic factor for ultimate functional outcome, and should be taken into account when a treatment recommendation is made. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.
ACR Appropriateness Criteria ® Pre-Irradiation Evaluation and Management of Brain Metastases
Lo, Simon S. , Gore, Elizabeth , Bradley, Jeffrey D. , Buatti, John M. , Germano, Isabelle M. , Ghafoori, A. Paiman, Henderson, M. , Murad, Gregory J. A. , Patchell, Roy A., Patel, Samir H. , Robbins, Jared R. , Robins, H. Ian, Vassil, Andrew D. , Wippold, Franz J. , Yunes, Michael J. , Videtic, Gregory M.M. , Bradley, Jeffrey , Buatti, John M

Journal of Palliative Medicine | June 27, 2014 | Volume: 17 | Issue: 8 | Pages: 880-886

10.1089/jpm.2014.9417 Get It

Abstract Pretreatment evaluation is performed to determine the number, location, and size of the brain metastases and magnetic resonance imaging (MRI) is the recommended imaging technique, particularly in patients being considered for surgery or stereotactic radiosurgery. A contiguous thin-cut volumetric MRI with gadolinium with newer gadolinium-based agents can improve detection of small brain metastases. A systemic workup and medical evaluation are important, given that subsequent treatment for the brain metastases will also depend on the extent of the extracranial disease and on the age and performance status of the patient. Patients with hydrocephalus or impending brain herniation should be started on high doses of corticosteroids and evaluated for possible neurosurgical intervention. Patients with moderate symptoms should receive approximately 4–8 mg/d of dexamethasone in divided doses. The routine use of corticosteroids in patients without neurologic symptoms is not necessary. There is no proven benefit of anticonvulsants in patient without seizures. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.