NOS Board of Directors


Dan L. Curtis, MD
Radiation Oncologist
Comprehensive Cancer Centers of Nevada

Dan Curtis, MD, is a radiation oncologist and one of the founding members of Comprehensive Cancer Centers. He is currently chief, subdivision radiation oncology at Summerlin Hospital Medical Center as well as chairman of its Cancer Conference, Breast Cancer Conference, Radiation Safety Committee, and tumor board. He is also assistant professor of internal medicine (radiation oncology) at University of Nevada, Reno School of Medicine as well as clinical assistant professor of internal medicine at UNLV School of Medicine.

In 2004, Dr. Curtis started the intravascular brachytherapy program at Valley Hospital. He also pioneered and facilitates regular cancer conferences and breast cancer conferences at Summerlin Hospital and in 1998, he started its prostate brachytherapy program.

Previously, Dr. Curtis was a radiation oncologist at Nevada Radiation Oncology Centers, which became Comprehensive in 2000. He was also part of a multispecialty group practicing internal medicine from 1984 to 1987.

Dr. Curtis has been named Top Doctor by Castle Connolly, US News & World Report, Desert Companion, Vegas Seven, Vegas Inc., and Greenspun Media Group. He has also been recognized by the American Registry as America’s Most Honored Professional.

Vice President


Souzan El-Eid, MD, FACS
Breast Surgical Oncologist
Comprehensive Cancer Centers of Nevada

Souzan El-Eid, MD, FACS, is a breast surgeon with Comprehensive Cancer Centers of Nevada and serves as the medical director of the Breast Care Center at Summerlin Hospital. Dr. El-Eid is currently the cancer liaison physician for the cancer program and co-chair of the breast tumor board as well as cancer committee at Summerlin Hospital. She is an adjunct associate professor of general surgery at Touro University Nevada and has served as principal investigator for several clinical research studies.

Dr. El-Eid is past president of Clark County Medical Society and an instructor at the American Society of Breast Surgeons’ Annual Meeting, teaching breast ultrasound and stereotactic breast biopsy. She was invited by the American Society of Clinical Oncology to review and publish clinical practice guidelines on surgical margins for breast-conserving surgery with whole-breast irradiation in stage I and II invasive breast cancer. The data was published by the Journal of Clinical Oncology.

Dr. El-Eid has been named Top Doctor by Vegas Seven and Desert Companion, Medical Marvels by Nevada Business Magazine, Distinguished Women in Nevada by Distinguished Publishing Company, Top Breast Surgeon by HealthTap, and America’s Most Compassionate Doctor as chosen by She has been recognized as Top Surgeon from Consumers’ Research Council of America and received the Cancer Liaison Physician, Outstanding Performance Award from the American College of Surgeons in 2006.


Annabel Barber, MD, FACS
Professor of Surgery
University of Nevada, School of Medicine

Annabel E. Barber, MD, FACS, is a Fellow of the American College of Surgeons, professor of surgery, and chief in the division of endocrine and gastrointestinal surgery for the UNLV School of Medicine. A past president of the Nevada Chapter of the American College of Surgeons, her community service work includes working with indigent women with breast cancer, health screening for seniors, and engagement with support groups for black women with breast cancer.

Dr. Barber graduated from the University of Texas Medical School at Houston. She completed her general surgery residency at New York Hospital-Cornell University Medical College, where she was also a research fellow in surgical nutrition and metabolism. She has served as chief, general surgery clinics at University Medical Center and chief of staff at MountainView Hospital, where she was also chief of general surgery.

Her research interests include interventions in wound healing for diabetics, and therapies, including diet, for Gastroparesis, a disorder that slows or stops the movement of food from the stomach to the small intestine.

Dr. Barber has been an invited lecturer throughout the United States on topics ranging from “Surgical Options in Colorectal Cancer” and “New Surgical Techniques in Breast Surgery” to “Hard to Heal Wounds & Nutrition” and “Nutrition Across the Critical Care Spectrum.”

Immediate Past President

Tejvir Singh, MD
Medical Oncologist/Hematologist
Reno Oncology Consultants

APP Membership Liaison

Shannon Southwick, MSN, APRN, FNP-BC, OCN
Nurse Practitioner
Comprehensive Cancer Centers of Nevada

Shannon Southwick, MSN, APRN, FNP-BC, OCN, is a board certified family nurse practitioner at Comprehensive Cancer Centers of Nevada (CCCN) where she provides oncology care and follow-up care to patients. She also teaches an introduction to chemotherapy class to all new patients.

Shannon has held various positions at CCCN including manAger of nursing services, implementation manager of electronic medical records, and registered nurse. Prior to joining CCCN, she worked as a registered nurse at Sunrise Hospital and Medical Center.

Shannon is a member of the Oncology Nursing Society and American Academy of Nurse Practitioners, and served as former president and vice president of the Greater Las Vegas ONS Chapter.



Michael Anderson, MD
Radiation Oncologist
Comprehensive Cancer Centers of Nevada

Michael Anderson, MD, is a radiation oncologist at Comprehensive Cancer Centers. He has authored/co-authored several publications and served as the Community Outreach Coordinator for the Sunrise Hospital Cancer Committee from 2007-2009 and was a member of the IRB Committee at University Medical Center from 2006-2009. Dr. Anderson was vital in starting and developing the practice’s accelerated partial breast irradiation program. Prior to joining Comprehensive in 2012, he worked in private practice as a radiation oncologist in Las Vegas. Dr. Anderson was the associate director for the department of radiation oncology at the NYC Health and Hospitals/Elmhurst from 2001-2002.

Dr. Anderson has been recognized as a Medical Marvel by the Nevada Business Magazine and Top Doctors by Castle Connolly, Vegas Inc., Greenspun Media Group, and Vegas Seven magazine. He has also been recognized by the American Registry as America’s Most Honored Professional.

Lawrence Dardick, MD
Lee S. Schwartzberg, MD, FACP
Chief, Section of Medical Oncology
Renown Health
Reno, NV

Lee Schwartzberg, MD, FACP, is chief in the section of medical oncology for Renown Health in Reno, Nevada. He completed fellowship training in medical oncology and hematology at Memorial Sloan Kettering Cancer Center, where he also served as Chief Medical Resident and was a founding member of the institutional ethics committee.

Dr. Schwartzberg is President/CMO for Vector Oncology, an oncology-specific SMO/CRO. He was awarded the 2004 Jefferson Award for community service. He served as the founding editor-in-chief of the journal Community Oncology and the website and serves on the editorial board of the Journal of Supportive Oncology. Dr. Schwartzberg’s major research interests are new therapeutic approaches to breast cancer, targeted therapy, and supportive care. He has authored over 110 research papers and maintains a private practice in medical oncology focusing on breast cancer.

W. Andrew Wang, MD
Radiation Oncologist
Comprehensive Cancer Centers of Nevada

W. Andrew Wang, MD, is a radiation oncologist at Comprehensive Cancer Centers of Nevada, where he brings the most modern experience in technology and procedures to the practice. Prior to joining Comprehensive Cancer Centers, Dr. Wang was a radiation oncology resident at the William Beaumont Hospital where he served as chief resident from July 2017-July 2018. His research and findings have appeared in a number of publications including the Journal of Neurosurgery, the Journal of Neuro-Oncology, and Physics in Medicine and Biology.

Lauren Zion, PharmD, BCOP, BCPS
Oncology Pharmacy Clinical Specialist
Renown Health

1801 Research Boulevard Suite 400
Rockville, MD 20850
Tel: 301.984.9496 | Fax: 301.770.1949
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