Anna-Maria De Costa, MD

Meet Anna-Maria De Costa, MD

Board-Certified Radiation Oncologist Bringing Cancer Research Expertise to Santa Fe

Dr. Anna-Maria De Costa is a board-certified radiation oncologist at the CHRISTUS Health Regional Cancer Center in Santa Fe, New Mexico. She holds both an MD and a PhD in immunology from the Medical University of South Carolina, a combination that reflects a physician who trained not only to treat cancer, but to study how the body's immune system responds to it. She completed her radiation oncology residency at the University of Wisconsin Hospital & Clinics, a facility consistently recognized among the nation's top cancer programs, and is the author or co-author of more than 10 peer-reviewed publications on topics ranging from MR-guided adaptive radiotherapy to immunotherapy in head and neck cancer. 

Career at a Glance

• Board-certified in Radiation Oncology by the American Board of Radiology
• MD and PhD (Immunology) from the Medical University of South Carolina, trained as both a clinician and a cancer researcher
• Residency in Radiation Oncology at the University of Wisconsin Hospital & Clinics, a nationally ranked cancer care program
• Published researcher: author or co-author of 10+ peer-reviewed publications on cancer immunology, MR-guided radiation therapy, and brachytherapy techniques
• High-volume breast cancer radiation treatment experience, including ductal carcinoma in situ and metastatic or recurrent breast cancer

Clinical Role

Dr. De Costa practices at the CHRISTUS Health Regional Cancer Center in Santa Fe, where she provides radiation therapy for adult patients with a range of cancer diagnoses. Radiation oncology is the medical specialty focused on using precisely targeted radiation to destroy cancer cells, shrink tumors, and reduce the risk of recurrence, often as part of a broader treatment plan that may include surgery, chemotherapy, or immunotherapy. Dr. De Costa's dual training in radiation oncology and immunology gives her a deeper understanding of how radiation interacts with the body's immune response, which is increasingly relevant as cancer care integrates immunotherapy with traditional treatment approaches.

She provides radiation treatment for conditions such as:

• Breast cancer: including ductal carcinoma in situ, invasive breast cancer, male breast carcinoma, metastatic or recurrent breast cancer, and Paget disease of the breast
• Head and neck cancers: including oral cancer and squamous cell carcinoma of the head and neck
• Cervical cancer requiring brachytherapy or external beam radiation
• Cancers requiring palliative radiation for symptom management, including pain relief and reduction of tumor-related swelling
• Lymphedema and radiation-related side effect management
• Other solid tumors amenable to radiation therapy as part of a multidisciplinary treatment plan

What You Can Expect from Care with Dr. De Costa

Cancer treatment is not one-size-fits-all, and a radiation oncologist's job begins long before the first treatment session. Dr. De Costa develops individualized radiation treatment plans based on the type, stage, and location of each patient's cancer, as well as the full picture of their health and treatment goals. Her PhD in immunology means she brings a research-informed perspective to how radiation therapy can be optimized not just in destroying cancer cells, but in how the body heals and responds after treatment. She works closely with surgical oncologists, medical oncologists, and other specialists to coordinate each patient's care.

You can expect:

• A detailed consultation to understand your diagnosis, explain radiation treatment options, and answer your questions before treatment begins
• An individualized treatment plan designed around your specific cancer type, stage, and health profile
• Coordination with your full oncology team: surgeons, medical oncologists, and support staff, to ensure your radiation plan fits within your overall treatment strategy
• Ongoing monitoring throughout your treatment course, with adjustments as needed based on how your body responds
• Access to a physician-scientist whose treatment decisions are grounded in current research on radiation biology and cancer immunology

Advanced Radiation Therapy

Dr. De Costa's training at the University of Wisconsin, a program with recognized expertise in radiation therapy innovation, prepared her to deliver the most current approaches to cancer treatment using radiation. Her published work reflects direct involvement with technologies that are shaping the future of radiation oncology:

• MR-Guided Online Adaptive Radiotherapy: Dr. De Costa has published on the clinical application of MR-guided adaptive radiotherapy, including rapid palliative single-session protocols. This approach uses real-time MRI imaging during treatment delivery, allowing the radiation plan to be adjusted on the spot to account for changes in tumor position, organ movement, or patient anatomy, resulting in more precise targeting and reduced exposure to healthy tissue.
• High-Dose-Rate Brachytherapy: Her published work includes implementation of a novel double-balloon breast brachytherapy applicator and the use of MRI guidance for HDR brachytherapy in cervical cancer. Brachytherapy delivers radiation directly to the tumor from inside the body, allowing higher doses to reach the cancer while sparing surrounding healthy tissue.
• Radiation Therapy Planning: Treatment planning using CT scans, MRI, and advanced imaging to map the precise location and shape of tumors before and during treatment.

For patients in Santa Fe, this means access to a radiation oncologist whose technical capabilities are informed by hands-on experience with some of the newest treatment delivery methods in the field.

Research, Clinical Insight, and Thought Leadership

Dr. De Costa is the author or co-author of more than 10 peer-reviewed publications spanning cancer immunology, radiation therapy techniques, and patient-centered quality measurement. Her research career began during her PhD in immunology at the Medical University of South Carolina, where she led studies on how the immune system changes as head and neck cancers develop, work that has direct implications for how immunotherapy and radiation can be combined. Her lead-authored publications include studies on the evolution of immune phenotype in squamous cell carcinoma of the head and neck, dendritic cell vaccine strategies for premalignant oral lesions, and a review of immunotherapy advances and limitations in head and neck cancer. During her residency at the University of Wisconsin, her research shifted toward clinical innovation in radiation delivery, including MR-guided adaptive radiotherapy and novel brachytherapy techniques for breast and cervical cancer. She also contributed to research on how HPV modulates therapeutic sensitivity in cancer treatment, and on incorporating patient satisfaction metrics into multidisciplinary breast cancer care quality assessment. This body of work means that when Dr. De Costa designs a radiation treatment plan, she is drawing on a scientific understanding of the disease that extends well beyond clinical training alone.