Nurse Practitioners

KATHY SIEU, RN, MS, ANP-C, AOCNP

KATHY SIEU, RN, MS, ANP-C, AOCNP

Kathy joined Contra Costa Oncology in 2008. She carries a double certification as a board certified adult nurse practitioner and as an Advanced Oncology Certified Nurse Practitioner. Kathy graduated with honors from UCSF’s Master’s Nurse Practitioner program. She, also, holds bachelor’s degrees in psychology/sociology and nursing. All degrees were conferred with honors and distinction. Her background includes many years of experience at Stanford University Hospital in primary care, trauma, intensive care, and cardiology. She has coordinated clinical medical research in interventional cardiology and radiology and continues to coordinate the practice’s clinical trials. Kathy continues to coordinate clinical trials for Contra Costa Oncology, as well as gently guiding patients through bone marrow biopsies.

Since graduation Kathy has pursued additional studies in Cancer Genetic Risk Assessment through the Oncology Nurses Society and more recently became a member of City of Hope’s community of practice upon completing their Intensive Course for Cancer Genetic Risk Assessment. Kathy has an active role in coordinating the American Cancer Society’s San Ramon site of Relay for Life and is a volunteer with the California Disaster Relief Medical Volunteers. In her spare time she enjoys physical fitness, time with family, travel, reading and hiking.

JULIA CEREDA, DNP, MSN, RN, AGACNP-BC

JULIA CEREDA, DNP, MSN, RN, AGACNP-BC

Julia joined Contra Costa Oncology in January 2023 as a board-certified adult-geriatric acute care nurse practitioner. She earned her Doctorate in Nursing Practice degree from the University of California San Francisco in 2022 and her Masters in Nursing from New York University in 2017. Her doctoral project focused on improving inpatient consultation requests. She also holds bachelor’s degrees in linguistics and nursing. Julia’s clinical nursing background includes seven years of experience as a critical care registered nurse working in burn, medical and surgical intensive care units. Her post-Master’s training includes a yearlong fellowship in oncological critical care at Memorial Sloan Kettering Cancer Center (MSKCC) in New York City. She subsequently worked as a consultant on the inpatient nephrology service at MSKCC from 2018-2020. Julia moved from New York City to the Bay Area in May, 2020. In her free time, she enjoys travel, hiking, dancing, and going to the theater.

STEPHANIE CHIU, BSN, RN, PCCN

STEPHANIE CHIU, BSN, RN, PCCN

Stephanie is a dedicated family nurse practitioner who brings a blend of knowledge and empathy to her practice. She has earned a Master’s of Science degree in nursing from Samuel Merritt University and possesses Bachelor’s of Science degrees in both psychobiology from UCLA and nursing from SMU.

Stephanie’s professional experience is marked by her time at John Muir Concord Medical Center as a registered nurse, specializing in cardiology and stroke care. Her background has not only equipped her with invaluable insights and expertise but also instilled in her a strong desire to serve as a patient advocate through education and support. She is deeply committed to providing evidence-based, compassionate care and creating meaningful connections with her patients.

Beyond her professional responsibilities, Stephanie finds joy in spending quality time with her family, exploring new places to eat, enjoying boba, staying active, and caring for her dog, Toastie.

Aleena Khan, DNP, NP-c, PHN

Aleena Khan, DNP, NP-c, PHN

Aleena has achieved a Doctorate in Nursing from Samuel Merritt University, where she also successfully earned her Master’s in Nursing and Bachelor of Nursing degrees. In addition to her nursing qualifications, Aleena holds a finance degree from San Jose State University.  She has a commitment to professional development and is currently pursuing oncology courses at Duke University with the aim of attaining a specialized Certificate in Oncology.

Aleena‘s professional journey is marked by her commitment to delivering the highest standard of care to oncology patients. Her multidisciplinary background equips her with the skills to approach cancer care holistically, ensuring that her patients receive not only the best medical treatment but also the compassionate support they need on their medical journey.

Furthermore, Aleena has completed the Intensive Course for Cancer Genetic Risk Assessment offered by the City of Hope, enhancing her understanding of cancer genetics and personalized medicine. In addition, Aleena generously volunteers her time to collaborate with the Oncology Nursing Society, contributing to the development of evidence-based nursing guidelines that support clinical decisions in oncology nursing.

Outside her professional commitments, Aleena treasures precious moments with her husband and three children. She has developed a passion for gardening and enjoys reading. Alongside these interests, she lovingly cares for her tuxedo cat, Figaro.

AJ Tio, MSN, RN, NP-c

AJ Tio, MSN, RN, NP-c

AJ joined Contra Costa Oncology in March 2023. He received his Bachelors Degree in Speech and Hearing Sciences from the University of Arizona, followed by his Masters Degree in Nursing from the University of San Diego. His nursing background includes working on a medical/surgical, telemetry and oncology floor at Sharp Chula Vista to being an infusion nurse at Stanford Healthcare. His nurse practitioner career began at Lucile Packard Hospital in Palo Alto, to being contracted by the Centers for Disease Control and Prevention during the COVID pandemic and finally landing in Contra Costa Oncology.

Outside of his professional responsibilities, AJ enjoys spending time with his family and friends. He enjoys participating in sports especially basketball and golf.