COVID-2019 Alert

The latest information about the 2019 Novel Coronavirus, including vaccine clinics for children ages 5 years old and older.

La información más reciente sobre el nuevo Coronavirus de 2019, incluidas las clínicas de vacunación para niños de 5 años en adelante.


Valentin Barsan, MD

  • Valentin Barsan
  • “The opportunity to help children keeps me motivated to constantly push for better outcomes.”

I like to understand the entire context of a diagnosis before proposing a treatment plan. I then share all the data that we have collected and put that in the context of what we understand in the field to practice the most up-to-date, evidence-based medicine. This allows us to personalize the treatment plan to enable the best outcomes for patients.

I enjoy the opportunity to communicate complex medical information in ways that explain the essence of what we are attempting to accomplish and take the journey with my patients, together.




Work and Education

Professional Education

Baylor College of Medicine, Houston, TX, 05/26/2015


UCSD Pediatric Residency, San Diego, CA, 06/30/2018


Stanford University Pediatric Hematology Oncology Fellowship, Palo Alto, CA, 6/30/2021

Board Certifications

Pediatrics, American Board of Pediatrics

Conditions Treated

Cancer Immunotherapy

CAR-T Cell Therapy

Pediatric Leukemia

Pediatric Lymphoma

All Publications

GD2 CAR T cells mediate clinical activity and manageable toxicity in children and young adults with DIPG and H3K27M-mutated diffuse midline gliomas. Majzner, R. G., Ramakrishna, S., Mochizuki, A., Patel, S., Chinnasamy, H., Yeom, K., Schultz, L., Richards, R., Campen, C., Reschke, A., Mahdi, J., Toland, A., Baggott, C., Mavroukakis, S., Egeler, E., Moon, J., Landrum, K., Erickson, C., Rasmussen, L., Barsan, V., Tamaresis, J. S., Marcy, A., Kunicki, M., Fujimoto, M., Ehlinger, Z., Kurra, S., Cornell, T., Partap, S., Fisher, P., Grant, G., Vogel, H., Sahaf, B., Davis, K., Feldman, S., Mackall, C. L., Monje, M. AMER ASSOC CANCER RESEARCH. 2021
SINGLE CELL RNA SEQUENCING FROM THE CSF OF SUBJECTS WITH H3K27M+DIPG/DMG TREATED WITH GD2 CAR T-CELLULAR THERAPY Mochizuki, A., Ramakrishna, S., Good, Z., Patel, S., Chinnasamy, H., Yeom, K., Schultz, L., Richards, R., Campen, C., Reschke, A., Mahdi, J., Toland, A., Baggot, C., Mavroukakis, S., Egeler, E., Moon, J., Landrum, K., Erickson, C., Rasmussen, L., Barsan, V., Tamaresis, J., Marcy, A., Kunicki, M., Celones, M., Ehlinger, Z., Kurra, S., Cornell, T., Partap, S., Fisher, P., Grant, G., Vogel, H., Davis, K., Feldman, S., Sahaf, B., Majzner, R., Mackall, C., Monje, M. OXFORD UNIV PRESS INC. 2021: 39
GD2 CAR T-CELLS MEDIATE CLINICAL ACTIVITY AND MANAGEABLE TOXICITY IN CHILDREN AND YOUNG ADULTS WITH H3K27M-MUTATED DIPG AND SPINAL CORD DMG Majzner, R., Ramakrishna, S., Mochizuki, A., Patel, S., Chinnasamy, H., Yeom, K., Schultz, L., Richards, R., Campen, C., Reschke, A., Mahdi, J., Martin, A., Toland, S., Baggott, C., Mavroukakis, S., Egeler, E., Moon, J., Landrum, K., Erickson, C., Rasmussen, L., Barsan, V., Tamaresis, J., Marcy, A., Kunicki, M., Fujimoto, M., Ehlinger, Z., Kurra, S., Cornell, T., Partap, S., Fisher, P., Grant, G., Vogel, H., Sahaf, B., Davis, K., Feldman, S., Mackall, C., Monje, M. OXFORD UNIV PRESS INC. 2021: 49-50
GENERALIZABILITY OF POTENTIAL BIOMARKERS OF RESPONSE TO CTLA-4 AND PD-1 BLOCKADE THERAPY IN CANCER Bortone, D., Vensko, S., Entwistle, S., Cogdill, A., Monette, A., Najjar, Y., Sweis, R., Tschernia, N., Wennerberg, E., Bommareddy, P., Haymaker, C., Khan, U., McGee, H., Park, W., Sater, H., Spencer, C., Ascierto, M., Barsan, V., Popat, V., Valpione, S., Wells, D., Thorsson, V., Zappasodi, R., Rudqvist, N., Vincent, B. BMJ PUBLISHING GROUP. 2020: A46A47
CONSTRUCTION OF THE IMMUNE LANDSCAPE OF DURABLE RESPONSE TO CHECKPOINT BLOCKADE THERAPY BY INTEGRATING PUBLICLY AVAILABLE DATASETS Rudqvist, N., Zappasodi, R., Wells, D., Thorsson, V., Cogdill, A., Monette, A., Najjar, Y., Sweis, R., Wennerberg, E., Bommareddy, P., Haymaker, C., Khan, U., McGee, H., Park, W., Sater, H., Spencer, C., Tschernia, N., Ascierto, M., Barsan, V., Popat, V., Valpione, S., Vincent, B. BMJ PUBLISHING GROUP. 2020: A5A6

View details for DOI 10.1136/LBA2019.8

View details for Web of Science ID 000540356400009

Prospects and Challenges for Use of CAR T Cell Therapies in Solid Tumors. Expert opinion on biological therapy Ramakrishna, S., Barsan, V., Mackall, C. 2020


Introduction: Chimeric antigen receptor (CAR) T cell therapy has provided patients with relapsed/refractory B cell malignancies with a new therapeutic option, but this class of therapeutics has not demonstrated consistent therapeutic benefit in solid tumors.Areas Covered: Here we review the literature to identify numerous factors that contribute to this discrepancy, using pediatric cancers as a platform to understand these limitations. We discuss an inability to target highly and homogenously expressed lineage-associated antigens due to risks of on-target, off-tumor toxicity, T cell dysfunction related to T cell exhaustion and the suppressive tumor microenvironment (TME), and inefficient CAR T cell trafficking into solid tumors. As our understanding of the biology of CAR T cells improves and innovations in engineering CAR platforms emerge, next generation CAR T cell therapeutics designed to overcome these challenges will enter the clinic for testing.Expert Opinion: New approaches to address the challenges that have limited the efficacy of CAR T cell therapeutics in solid tumors are emerging. These include next-generation CAR T cell engineering to overcome antigen heterogeneity, to mitigate T cell exhaustion and to prevent suppression by the TME, and novel approaches for regional delivery to overcome limitations in tumor T cell trafficking.

View details for DOI 10.1080/14712598.2020.1738378

View details for PubMedID 32125191

Immunotherapy for the Treatment of Acute Lymphoblastic Leukemia. Current oncology reports Barsan, V., Ramakrishna, S., Davis, K. L. 2020; 22 (2): 11


PURPOSE OF REVIEW: Immunotherapy for the treatment of acute lymphoblastic leukemia (ALL) broadens therapeutic options beyond chemotherapy and targeted therapy. Here, we review the use of monoclonal antibody-based drugs and cellular therapies to treat ALL. We discuss the challenges facing the field regarding the optimal timing and sequencing of these therapies in relation to other treatment options as well as considerations of cost effectiveness.RECENT FINDINGS: By early identification of patients at risk for leukemic relapse, monoclonal antibody and cellular immunotherapies can be brought to the forefront of treatment options. Novel CAR design and manufacturing approaches may enhance durable patient response. Multiple clinical trials are now underway to evaluate the sequence and timing of monoclonal antibody, cellular therapy, and/or stem cell transplantation. The biologic and clinical contexts in which immunotherapies have advanced the treatment of ALL confer optimism that more patients will achieve durable remissions. Immunotherapy treatments in ALL will expand through rationally targeted approaches alongside advances in CAR T cell therapy design and clinical experience.

View details for DOI 10.1007/s11912-020-0875-2

View details for PubMedID 31997022

Toward a comprehensive view of cancer immune responsiveness: a synopsis from the SITC workshop. Journal for immunotherapy of cancer Bedognetti, D., Ceccarelli, M., Galluzzi, L., Lu, R., Palucka, K., Samayoa, J., Spranger, S., Warren, S., Wong, K., Ziv, E., Chowell, D., Coussens, L. M., De Carvalho, D. D., DeNardo, D. G., Galon, J., Kaufman, H. L., Kirchhoff, T., Lotze, M. T., Luke, J. J., Minn, A. J., Politi, K., Shultz, L. D., Simon, R., Thorsson, V., Weidhaas, J. B., Ascierto, M. L., Ascierto, P. A., Barnes, J. M., Barsan, V., Bommareddy, P. K., Bot, A., Church, S. E., Ciliberto, G., De Maria, A., Draganov, D., Ho, W. S., McGee, H. M., Monette, A., Murphy, J. F., Nistico, P., Park, W., Patel, M., Quigley, M., Radvanyi, L., Raftopoulos, H., Rudqvist, N., Snyder, A., Sweis, R. F., Valpione, S., Butterfield, L. H., Disis, M. L., Fox, B. A., Cesano, A., Marincola, F. M., Society for Immunotherapy of Cancer (SITC) Cancer Immune Responsiveness Task Force and Working Groups 2019; 7 (1): 131


Tumor immunology has changed the landscape of cancer treatment. Yet, not all patients benefit as cancer immune responsiveness (CIR) remains a limitation in a considerable proportion of cases. The multifactorial determinants of CIR include the genetic makeup of the patient, the genomic instability central to cancer development, the evolutionary emergence of cancer phenotypes under the influence of immune editing, and external modifiers such as demographics, environment, treatment potency, co-morbidities and cancer-independent alterations including immune homeostasis and polymorphisms in the major and minor histocompatibility molecules, cytokines, and chemokines. Based on the premise that cancer is fundamentally a disorder of the genes arising within a cell biologic process, whose deviations from normality determine the rules of engagement with the host's response, the Society for Immunotherapy of Cancer (SITC) convened a task force of experts from various disciplines including, immunology, oncology, biophysics, structural biology, molecular and cellular biology, genetics, and bioinformatics to address the complexity of CIR from a holistic view. The task force was launched by a workshop held in San Francisco on May 14-15, 2018 aimed at two preeminent goals: 1) to identify the fundamental questions related to CIR and 2) to create an interactive community of experts that could guide scientific and research priorities by forming a logical progression supported by multiple perspectives to uncover mechanisms of CIR. This workshop was a first step toward a second meeting where the focus would be to address the actionability of some of the questions identified by working groups. In this event, five working groups aimed at defining a path to test hypotheses according to their relevance to human cancer and identifying experimental models closest to human biology, which include: 1) Germline-Genetic, 2) Somatic-Genetic and 3) Genomic-Transcriptional contributions to CIR, 4) Determinant(s) of Immunogenic Cell Death that modulate CIR, and 5) Experimental Models that best represent CIR and its conversion to an immune responsive state. This manuscript summarizes the contributions from each group and should be considered as a first milestone in the path toward a more contemporary understanding of CIR. We appreciate that this effort is far from comprehensive and that other relevant aspects related to CIR such as the microbiome, the individual's recombined T cell and B cell receptors, and the metabolic status of cancer and immune cells were not fully included. These and other important factors will be included in future activities of the taskforce. The taskforce will focus on prioritization and specific actionable approach to answer the identified questions and implementing the collaborations in the follow-up workshop, which will be held in Houston on September 4-5, 2019.

View details for DOI 10.1186/s40425-019-0602-4

View details for PubMedID 31113486

Clinical Impact of Next-generation Sequencing in Pediatric Neuro-Oncology Patients: A Single-institutional Experience. Cureus Barsan, V. n., Paul, M. n., Gorsi, H. n., Malicki, D. n., Elster, J. n., Kuo, D. J., Crawford, J. n. 2019; 11 (12): e6281


The implementation of next-generation sequencing (NGS) in pediatric neuro-oncology may impact diagnosis, prognosis, therapeutic strategies, clinical trial enrollment, and germline risk. We retrospectively analyzed 58 neuro-oncology patients (31 boys, 27 girls, average age 7.4 years) who underwent NGS tumor profiling using a single commercially available platform on paraffin-embedded tissue obtained at diagnosis (20 low-grade gliomas, 12 high-grade gliomas, 11 embryonal tumors, four ependymal tumors, three meningeal tumors, and eight other CNS tumors) from May 2014 to December 2016. NGS results were analyzed for actionable mutations, variants of unknown significance and clinical impact. Seventy-four percent of patients (43 of 57) had actionable mutations; 26% had only variants of uncertain significance (VUS). NGS findings impacted treatment decisions in 55% of patients; 24% were given a targeted treatment based on NGS findings. Seven of eight patients with low-grade tumors treated with targeted therapy (everolimus, trametinib, or vemurafenib) experienced partial response or stable disease. All high-grade tumors had progressive disease on targeted therapy. Forty percentof patients had a revision or refinement of their diagnosis, and nine percent of patients were diagnosed with a previously unconfirmed cancer predisposition syndrome. Turnaround time between sample shipment and report generation averaged 13.4 6.4 days. One sample failed due to insufficient DNA quantity. Our experience highlights the feasibility and clinical utility of NGS in the management of pediatric neuro-oncology patients. Future prospective clinical trials using NGS are needed to establish efficacy.

View details for DOI 10.7759/cureus.6281

View details for PubMedID 31827999

View details for PubMedCentralID PMC6892579

Primer on Cancer Immunotherapy and the Targeting of Native Proteins Early Phase Cancer Immunotherapy Barsan, V., Tumeh, P. Springer. 2018


Sacrectomy remains a technically complex procedure for resection of malignant pelvic neoplasia. Commonly, postoperative complications include permanent neurological deficits. Only a few studies have reported the long-term functional outcomes of patients who had undergone sacrectomy.We previously reported on the utilization of complete sacrectomy and lumbopelvic reconstruction for the management of primary myofibroblastic sarcoma of the sacrum and ilium in a 15-year-old female patient. In this report, we update her postoperative course with an additional 5years of follow-up and Health-Related Quality of Life (HRQoL) outcomes. During this time period, she gave birth to two healthy full-term babies.To the best of our knowledge, this is the first report of pregnancy after total sacrectomy and lumbopelvic reconstruction. We outline some of the challenges in the obstetrical management of this patient.

View details for PubMedID 26728010

Long-term follow-up and pregnancy after complete sacrectomy with lumbopelvic reconstruction: case report and literature review BMC PREGNANCY AND CHILDBIRTH Barsan, V. V., Briceno, V., Gandhi, M., Jea, A. 2016; 16: 1


Currently, very few prognosticators accurately predict metastasis in cancer patients. In order to complete the metastatic cascade and successfully colonize distant sites, carcinoma cells undergo dynamic epithelial-mesenchymal-transition (EMT) and its reversal, mesenchymal-epithelial-transition (MET). While EMT-centric signatures correlate with response to therapy, they are unable to predict metastatic outcome. One reason is due to the wide range of transient phenotypes required for a tumor cell to disseminate and recreate a similar histology at distant sites. Since such dynamic cellular processes are also seen during embryo development (epithelial-like epiblast cells undergo transient EMT to generate the mesoderm, which eventually redifferentiates into epithelial tissues by MET), we sought to utilize this unique and highly conserved property of cellular plasticity to predict metastasis. Here we present the identification of a novel prognostic gene expression signature derived from mouse embryonic day 6.5 that is representative of extensive cellular plasticity, and predicts metastatic competence in human breast tumor cells. This signature may thus complement conventional clinical parameters to offer accurate prediction for outcome among multiple classes of breast cancer patients.

View details for PubMedID 26123483

A novel embryonic plasticity gene signature that predicts metastatic competence and clinical outcome SCIENTIFIC REPORTS Soundararajan, R., Paranjape, A. N., Barsan, V., Chang, J. T., Mani, S. A. 2015; 5: 11766