808 North 39th Avenue,
Yakima, WA 98902 Map this address

(509)574-3400 Fax: (509)249-4458

Monday to Friday, 8 a.m. to 5 p.m.

Our Providers

Medical Oncology

Mario Chenal, MD

Mario Chenal, MD


Philosophy of Care

Our patients are at the center of a team effort involving the family, support staff and health care providers.

As a health care provider I intend to deliver good quality of care, using best available clinical evidence and compassionate manners.

I consider a privilege to be a part of this team.

Other specialties: Medical Oncology and Hematology

Medical school: Universidad de San Carlos, Guatemala

Residency: St. Vincent Hospital & Health Center, Indianapolis, IN

Fellowship: University of Texas at Southwestern, Dallas, TX

Board-certified: Board Certified by ABIM in Hematology and Medical Oncology

Master in Health Informatics at University of Washington, WA

Siva Mannem, MD

Siva Mannem, MD, Oncology

Medical Oncology

Philosophy of Care

Take care of the patient and the rest will follow. It's really tough to envision yourself in the patient's role, especially with cancer.

Medical school: Osmania Medical College, NTR University of Health Sciences, Hyderabad, India

Residency: Internal Medicine, University of Texas Medical Branch, Galveston, Texas

Fellowship: Medical Oncology, University of Texas Medical Branch, Galveston, Texas

Sri Obulareddy

Sri Obulareddy,  MD

Medical Oncology

Medical school: Andhra Medical College, Dr. NTR University of Health Sciences, AP, India, 1999-2004

Residency: Internal Medicine, the University of Texas Medical Branch in Galveston, Texas, 2011-2014; Hematology and Oncology, Yashoda Cancer and Multispecialty Center, Hyderabad, India, 2004-2006.

Fellowship: Medical Oncology, the University of Texas Medical Branch, 2014-2016.

What inspired you to choose medicine? That’s all I wanted to do as far as I can remember.

Why did you choose your specialty? I worked for two years in oncology after medical school. In oncology I was talking to the patients and their families, and I knew this is what I wanted to do. Oncology is not about just about treating the patients, it’s about treating families, too.

What is your philosophy of care? Providing compassionate care. Also, we need to listen to our patients, what they want, and then provide them with the best individualized care.

What do you like about Yakima? I like everything about Yakima. Our house has a beautiful valley view.

What do you like to do outside of work? I like exploring the outdoors; hiking and fishing. We also travel a lot. My sister is in Holland, and my parents are in India.

What do you like about North Star? Everybody’s so wonderful there. Who wouldn’t want to work at North Star? It’s all integrated; radiation and oncology. If you need somebody they’re just next door or downstars. It’s very approachable, and everybody’s so down to earth and easy to work with.

William Rubin, MD

William Rubin, MD

Medical Oncology

Medical school: Washington University School of Medicine

Residency: University of Arizona Health Sciences Center

Fellowship: Fred Hutchinson Cancer Research Center

Fran Hull

Fran Hull



Gonzaga University

Spokane, WA

Residency: I completed clinical rotations for my Family Nurse Practitioner education at the Yakima County Jail, Yakima Valley Farmworker’s Clinic, and the free clinic at Union Gospel Mission in Yakima.

Fellowship:  I completed a LEND (leadership and education in neurodevelopmental and related disabilities) training program through the University of Washington. Here I developed an understanding of the many biopsychosocial challenges that our community members with physical, mental, or intellectual disabilities face in our society, and a passion for advocating for equal opportunities.

What inspired you to choose medicine? I love chess, and I love nursing. Being a nurse practitioner is a process much like the game of chess in that I get to consider many different aspects of the patient, and use these clues and bits of information to find the best plan of action to reach the goal.

Why did you choose your specialty? My specialty chose me. I wasn’t sure where I was going to go after finishing my Master’s Degree, and I found North Star Lodge. I spoke with team members, researched the field, and ultimately determined that the field of oncology and I are well-suited. Oncology is intellectually stimulating and my experience in mental and behavioral health is an important component in the biopsychosocial care of my clients.

What is your philosophy of care? My favorite model of care is “biopsychosocial care.” This model of care focuses on the:

“Bio”- Referring to the physical illness.

“Psycho”- Is the mental health piece.

“Social”- Does the client have everything they need in their home life and relationships?

My goal is to address each of these with every client, and help them access resources as needed.

What do you like about Yakima? I like that we have White Pass Ski resort located so nearby. We have great cultural diversity in our community, and we have sunshine almost year-round.

What do you like to do outside of work? Outside of work I spend my time skiing, volunteering, and enjoying pickleball and softball with my kids and my husband, Derek. I also enjoy a good nap and a good cup of coffee!

What do you like about North Star? I like that they try and create a really welcoming place for care. The multidisciplinary framework enables the patients to have good, quality, holistic care.

Judith L. Mackey, ARNP

Judith Mackey


Education: Simmons College, Boston, Massachusetts - Masters of Science in Nursing, Family Nurse Practitioner.

New Mexico State University, Las Cruces, Mexico - Bachelors of Science in Nursing.

La Universidad de Guanajuato, Guanajuato, Mexico, Accredited with Southern Oregon University - Spanish Foreign Exchange Program.

Southern Oregon University, Ashland, Oregon - Bachelors of Arts in Communication.

What do you like to do outside of work? International Travel, Fine Arts, Beachcombing, Spelunking, Scuba Diving and Trail Hiking.

Sara Wisner

Sara Wisner

Nurse Practitioner

Cheryl Davison MD

Cheryl Davison MD

Director, Radiation Oncology

Philosophy of Care

I chose the specialty of Radiation Oncology because it combines my interest in technology with my desire to help patients, to fight their disease and become cancer survivors. I chose to join North Star to work with the wonderful dedicated staff, in a nurturing environment, with the support of excellent technology.

Other specialties: Oncology

Medical school: Michigan State University 1986

Residency: Duke University Hospital 1990

Board-certified: Am Bd Radiology (Radiation Oncology)

Steven P. Register MD

Steven P. Register MD

Radiation Oncology

Philosophy Of Care:

The heart of my medical philosophy is to offer individualized patient care. Having worked in a private cancer care center AND in a public hospital, I know that one approach doesn't fit every situation -patients are unique and each have different challenges to be met.

Medical school: The Ohio State University College of Medicine, 2008

Residency: Radiation Oncology, University of Miami, 2014

Board Certified: The American Board of Radiology, 2015

General Surgery

Cascade Surgical Partners

Call: (509)575-3946
Fax: (509)225-6449
Address: 3003 Tieton Dr., Suite 300, Yakima, WA 98902 Map this address
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Pain Management

Water's Edge

Contact: (509) 574-3805
Fax: (509) 225-2717
Address: 1460 N. 16th Ave., Suite D, Yakima, WA 98902 Map this address
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