Procedure Volume Patient Data Patient Conditions Reviews General Payments Back to Top

Home > CA Providers > Radiation Oncologists

Dr. Robert Blair Ash, MD

Accepting New Patients

(No ratings)

Specializes in: Radiation Oncology

Memorial University of Newfoundland Faculty of Medicine

Professional interests include: urologic (genitourinary) disorders, tumor, prostate brachytherapy, and more.

1100 West Stewart Drive
Orange, CA 92868

(714) 771-8153

Dr. Robert Blair Ash, MD is a radiation oncologist in Orange, CA specializing in radiation oncology. He graduated from Memorial University of Newfoundland Faculty of Medicine. Dr. Robert Blair Ash, MD is affiliated with Providence Medical Foundation, Children's Hospital of Orange County, Providence, St. Joseph Hospital Melanoma and Skin Cancer Program - Orange, St. Joseph Hospital Thoracic Oncology Program - Orange, St. Joseph Hospital Colorectal Cancer Program - Orange, St. Jude Medical Center (Fullerton), Providence St. Joseph Hospital Orange - Breast Program, Providence St. Joseph Hospital - Orange, St. Joseph Hospital Neuro-Oncology Program - Orange, St. Joseph Hospital Urologic Oncology Program - Orange, St. Joseph Hospital (Orange), St. Joseph Hospital Center for Cancer Prevention and Treatment Programs - Orange, Providence Affiliated Physicians, St. Joseph and St. Joseph Hospital Liver Bile Duct and Pancreas Tumor Program - Orange.

Office Locations

St. Joseph Hospital Liver Bile Duct and Pancreas Tumor Program - Orange

1000 West La Veta Avenue
Orange, CA 92868

(714) 734-6250

open_in_new

1100 West Stewart Drive
Orange, CA 92868

(714) 771-8153

(714) 744-8573

open_in_new

Some issues Dr. Robert Blair Ash, MD can help you with:

External Beam Radiation Therapy (EBRT)

External beam radiation therapy (EBRT) is a type of cancer treatment that delivers radiation from outside of the body. The goal of EBRT is to destroy cancer cells and shrink tumors, although it may also be used to alleviate symptoms rather than cure cancer.

EBRT can be delivered through several different methods, which may be combined or used alone. The type and length of treatment vary based on the location of the cancer or tumor and its size. Techniques for EBRT include:

Conventional external beam radiation therapy, which delivers a single beam of radiation from multiple directions. Conventional EBRT is commonly used to treat brain tumors, particularly when the entire brain needs treatment.
Intensity-modulated radiation therapy (IMRT), which uses smaller beams with adjustable intensity levels, so the most intense beams can be directed at the tumor. IMRT is used in several types of cancers, including prostate, gastrointestinal, brain, and lung cancers.
Orthovoltage, which uses low energy X-rays that do not penetrate the skin very deeply. Orthovoltage is typically used for skin cancers or other skin conditions.
Proton therapy, which uses a particle accelerator to deliver positively charged particles (protons) for cancer treatment. Proton beams can be controlled more precisely than X-rays, so there is less risk of damage to healthy tissue. This makes proton therapy a good option for younger patients, as other types of EBRT pose long-term risks such as growth problems and heart disease.
Stereotactic radiosurgery (SRS), which is a non-surgical type of radiation therapy that uses 3-D imaging to directly target tumors and avoid healthy tissue. SRS is often used for small tumors, particularly those in the brain (cranial radiosurgery) and spine (spinal radiosurgery). When performed outside of the brain and spine, it is called stereotactic body radiation therapy (SBRT).

Typically, patients will undergo treatment for five days a week over the course of several weeks, and they should be able to go home the same day. Each session can take less than an hour, with most of the time spent determining proper positioning of the body. Actual delivery of the radiation may only take a few minutes, and patients will wear a lead shield to protect healthy body tissues while receiving their treatment.

EBRT is painless, but it does come with some side effects, such as fatigue. Over the course of the therapy, oncologists will monitor patients' conditions and adjust their dosage, number of sessions, and length of treatment based on their body's response to the radiation.

Prostate Brachytherapy

Prostate brachytherapy is a type of internal radiation therapy used to treat prostate cancer. Brachytherapy and other internal radiation therapies place radioactive material inside of the body so that radiation can be released directly in the area of the cancer or tumor. Prostate brachytherapy uses radioactive seeds or pellets implanted into the prostate gland using thin tubes (catheters) or needles. The seed implants can be left in temporarily (temporary brachytherapy), meaning all radioactive material is removed following a treatment session, or they may be left in permanently (permanent brachytherapy). Permanent brachytherapy seeds will give off radiation slowly over the course of several weeks or months. Because radioactivity lessens over time, eventually, the amount of radiation released will become negligible, and the seeds will remain in the prostate gland without causing any side effects.

A group of doctors, including a radiation oncologist, will determine the details of a patient's treatment plan, such as length of treatment and whether they will receive low dose rate or high dose rate brachytherapy. Low dose rate brachytherapy may be temporary or permanent. If temporary, patients will remain in the hospital for several days while the radiation is delivered to their prostate gland through catheters or needles. In contrast, high dose rate brachytherapy delivers a high amount of radiation over a period of about thirty minutes, after which the radioactive materials are removed from the prostate. High dose rate brachytherapy is always temporary. Patients may receive a single treatment session, or treatment may continue in multiple sessions. Sessions can occur either in a single day or across several days, during which patients remain in the hospital.

Typically, patients can return home within hours following treatment, although an overnight hospital stay may be required. Side effects from prostate brachytherapy are temporary and may include erectile dysfunction, pelvic pain, fatigue, and urinary incontinence. If a patient feels pain or swelling where the needles or catheters were inserted, it may help them to avoid activities such as bike riding. Normal activity can be resumed within days of the procedure.

Radioembolization (Selective Internal Radiation Therapy)

Radioembolization, or selective internal radiation therapy (SIRT), is a minimally invasive procedure that uses radiation to treat liver tumors. By targeting the hepatic artery, or the main blood vessel that supplies the liver, radioembolization can cut off the blood supply to liver tumors. The tumors shrink, and minimal damage is done to healthy tissue. Radioembolization is a treatment option for tumors that cannot be removed by surgery or other radiation therapies, for liver cancer that is confined to the liver, or for liver cancer patients that have more than 3 months of life expectancy.

To perform radioembolization, a catheter is inserted into an artery in the groin and threaded to the liver. Radioactive beads, or pellets, are delivered through the catheter. The pellets will continuously deliver radiation for 10-14 days. The pellets will remain in the body permanently without causing any complications. If the tumor or cancer is confined to one portion of the liver, radioembolization will be performed in one treatment session. If both sides of the liver are affected, a second treatment session will be done about 8 weeks after the first.

Typically, most patients can return home and do light activity within hours following the procedure. Patients will be given medication to treat any possible side effects, which can include nausea, fever, abdominal pain, or tiredness.

Noteworthy Medicare Patient Procedures Performed by Dr. Robert Blair Ash, MD in 2023

Click on any procedure below to see further details on volume and pricing among Medicare patients.

Top 25%

By Affordability:

radiation therapy

In 2012, Dr. Robert Blair Ash, MD had a list price for radiation therapy that was lower than the list prices billed to Medicare by 75% of providers in related specialties within California. Actual amounts paid by patients can vary widely depending on a number of factors, including insurance coverage. A lower list price, however, might mean lower fees when paying without insurance.

Medicare Procedure and Patient Information

2012 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2012 were radiation therapy and marker placement for prostate radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	520
marker placement for prostate radiation therapy	11
radiation therapy	34

Medicare Procedure and Patient Information

2013 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2013 were radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	538
radiation therapy	27

2013 Medicare Patient Data

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	127
Female	53

**Ethnicity**
Non-Hispanic White	147
Black	0
Hispanic	18
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	88
From 75 to 84	71
85 and over	0
Less than 65	0

Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD in 2013

Hypertension	68
High Cholesterol	61
Stroke	0
Ischemic Heart Disease	45
Depression	16
Chronic Kidney Disease	28
Asthma	7
Osteoperosis	10
Atrial Fibrilation	13
Heart Failure	16
Chronic Obstructive Pulmonary Disease	17
Diabetes	28
Dementia	0
Cancer	75

Medicare Procedure and Patient Information

2014 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2014 were radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	425
radiation therapy	18

2014 Medicare Patient Data

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	110
Female	58

**Ethnicity**
Non-Hispanic White	129
Black	0
Hispanic	22
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	90
From 75 to 84	54
85 and over	0
Less than 65	0

Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD in 2014

Hypertension	71
High Cholesterol	63
Stroke	7
Ischemic Heart Disease	47
Depression	17
Chronic Kidney Disease	27
Asthma	7
Osteoperosis	9
Atrial Fibrilation	10
Heart Failure	16
Chronic Obstructive Pulmonary Disease	20
Diabetes	27
Dementia	0
Cancer	75

Medicare Procedure and Patient Information

2015 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2015 were radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	528
radiation therapy	19

2015 Medicare Patient Data

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	272
Female	156

**Ethnicity**
Non-Hispanic White	356
Black	0
Hispanic	42
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	168
From 75 to 84	162
85 and over	0
Less than 65	0

Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD in 2015

Hypertension	73
High Cholesterol	63
Stroke	7
Ischemic Heart Disease	47
Depression	18
Chronic Kidney Disease	29
Asthma	11
Osteoperosis	8
Atrial Fibrilation	16
Heart Failure	20
Chronic Obstructive Pulmonary Disease	16
Diabetes	28
Dementia	8
Cancer	65

Medicare Procedure and Patient Information

2016 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2016 were radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	465
radiation therapy	24

2016 Medicare Patient Data

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	108
Female	67

**Ethnicity**
Non-Hispanic White	139
Black	0
Hispanic	15
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	73
From 75 to 84	69
85 and over	0
Less than 65	0

Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD in 2016

Hypertension	69
High Cholesterol	59
Stroke	0
Ischemic Heart Disease	49
Depression	14
Chronic Kidney Disease	23
Asthma	14
Osteoperosis	8
Atrial Fibrilation	10
Heart Failure	16
Chronic Obstructive Pulmonary Disease	13
Diabetes	22
Dementia	9
Cancer	75

Medicare Procedure and Patient Information

2017 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2017 were radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	399
radiation therapy	32

2017 Medicare Patient Data

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	101
Female	64

**Ethnicity**
Non-Hispanic White	133
Black	0
Hispanic	19
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	65
From 75 to 84	64
85 and over	0
Less than 65	0

Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD in 2017

Hypertension	75
High Cholesterol	56
Stroke	0
Ischemic Heart Disease	45
Depression	19
Chronic Kidney Disease	30
Asthma	0
Osteoperosis	13
Atrial Fibrilation	16
Heart Failure	22
Chronic Obstructive Pulmonary Disease	12
Diabetes	27
Dementia	8
Cancer	75

Medicare Procedure and Patient Information

2018 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2018 were radiation therapy and marker placement for prostate radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	465
marker placement for prostate radiation therapy	11
radiation therapy	25

2018 Medicare Patient Data

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	120
Female	73

**Ethnicity**
Non-Hispanic White	145
Black	0
Hispanic	22
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	85
From 75 to 84	72
85 and over	0
Less than 65	0

Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD in 2018

Hypertension	74
High Cholesterol	66
Stroke	0
Ischemic Heart Disease	45
Depression	14
Chronic Kidney Disease	36
Asthma	0
Osteoperosis	9
Atrial Fibrilation	13
Heart Failure	18
Chronic Obstructive Pulmonary Disease	12
Diabetes	20
Dementia	9
Cancer	75

Medicare Procedure and Patient Information

2019 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2019 were radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	368
radiation therapy	24

2019 Medicare Patient Data

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	104
Female	71

**Ethnicity**
Non-Hispanic White	125
Black	0
Hispanic	26
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	78
From 75 to 84	70
85 and over	0
Less than 65	0

Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD in 2019

Hypertension	75
High Cholesterol	64
Stroke	0
Ischemic Heart Disease	48
Depression	24
Chronic Kidney Disease	39
Asthma	0
Osteoperosis	10
Atrial Fibrilation	12
Heart Failure	18
Chronic Obstructive Pulmonary Disease	18
Diabetes	24
Dementia	7
Cancer	75

Medicare Procedure and Patient Information

2020 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2020 were radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	337
radiation therapy	25

2020 Medicare Patient Data

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	112
Female	69

**Ethnicity**
Non-Hispanic White	138
Black	0
Hispanic	24
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	79
From 75 to 84	69
85 and over	0
Less than 65	0

Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD in 2020

Hypertension	68
High Cholesterol	62
Stroke	0
Ischemic Heart Disease	50
Depression	16
Chronic Kidney Disease	34
Asthma	0
Osteoperosis	7
Atrial Fibrilation	12
Heart Failure	15
Chronic Obstructive Pulmonary Disease	17
Diabetes	24
Dementia	9
Cancer	75

Medicare Procedure and Patient Information

2021 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2021 were radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	367
radiation therapy	16

2021 Medicare Patient Data

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	105
Female	69

**Ethnicity**
Non-Hispanic White	132
Black	0
Hispanic	20
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	79
From 75 to 84	62
85 and over	0
Less than 65	0

Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD in 2021

Hypertension	70
High Cholesterol	68
Stroke	0
Ischemic Heart Disease	46
Depression	17
Chronic Kidney Disease	30
Asthma	0
Osteoperosis	9
Atrial Fibrilation	13
Heart Failure	13
Chronic Obstructive Pulmonary Disease	16
Diabetes	24
Dementia	9
Cancer	75

Medicare Procedure and Patient Information

2022 Medicare Procedure Volume

The top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA during 2022 were radiation therapy.

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

doctor visit	456
radiation therapy	24

2022 Medicare Patient Data

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	114
Female	87

**Ethnicity**
Non-Hispanic White	156
Black	0
Hispanic	19
Asian	0
Other	0
Native American	0

**Age**
From 65 to 74	85
From 75 to 84	78
85 and over	0
Less than 65	0

Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD in 2022

Hypertension	73
High Cholesterol	75
Stroke	6
Ischemic Heart Disease	29
Depression	18
Chronic Kidney Disease	19
Asthma	11
Osteoperosis	13
Atrial Fibrilation	16
Heart Failure	14
Chronic Obstructive Pulmonary Disease	18
Diabetes	26
Dementia	6
Cancer	75

Medicare Procedure and Patient Information

Average Medicare Procedure Volume From 2012 - 2022

Volume of procedures performed by Dr. Robert Blair Ash, MD for Medicare patients.

The highest averages for the top procedures that Dr. Robert Blair Ash, MD treated as a radiation oncologist in Orange, CA were radiation therapy.

doctor visit	442
radiation therapy	24

Average Medicare Patient Data From 2012 - 2022

Information about Medicare patients treated by Dr. Robert Blair Ash, MD.

**Gender**
Male	115
Female	69

**Ethnicity**
Black / African American	0
Asian / Pacific Islander	0
Non-Hispanic White	145
Hispanic	20
Native American / Alaskan Native	0
Other	0

**Age**
75 to 84	70
85 and over	0
Less than 65	0
65 to 74	80

Average of Total of Conditions of Medicare patients treated by Dr. Robert Blair Ash, MD From 2012 - 2022

The highest averages of the most common conditions of Medicare patients that Dr. Robert Blair Ash, MD treated were cancer, hypertension, high cholesterol and ischemic heart disease.

Hypertension	65
High Cholesterol	57
Stroke	1
Ischemic Heart Disease	41
Depression	15
Chronic Kidney Disease	26
Asthma	4
Osteoporosis	8
Heart Failure	15
Chronic Obstructive Pulmonary Disease	14
Diabetes	22
Atrial Fibrillation	11
Cancer	67
Dementia	5

Education & Training

Dr. Robert Blair Ash, MD graduated from Memorial University of Newfoundland Faculty of Medicine. He completed residency at The University of Western Ontario Affiliated Hospitals. He is certified by the Board Certification: Radiation Oncology and has a state license in California.

Medical School: Memorial University of Newfoundland Faculty of Medicine

Residency: The University of Western Ontario Affiliated Hospitals

Board Certification: Board Certification: Radiation Oncology

Licensed In: California

Affiliations & Hospitals

Dr. Robert Blair Ash, MD is associated with these hospitals and organizations:

Providence Medical Foundation

Children's Hospital of Orange County

Providence

St. Joseph Hospital Melanoma and Skin Cancer Program - Orange

St. Joseph Hospital Thoracic Oncology Program - Orange

St. Joseph Hospital Colorectal Cancer Program - Orange

St. Jude Medical Center (Fullerton)

Providence St. Joseph Hospital Orange - Breast Program

Providence St. Joseph Hospital - Orange

St. Joseph Hospital Neuro-Oncology Program - Orange

St. Joseph Hospital Urologic Oncology Program - Orange

St. Joseph Hospital (Orange)

St. Joseph Hospital Center for Cancer Prevention and Treatment Programs - Orange

Providence Affiliated Physicians, St. Joseph

St. Joseph Hospital Liver Bile Duct and Pancreas Tumor Program - Orange

Insurance Information

Please note: Insurance information may change at any time, and the provider may accept your insurance plan even if it is not listed below. Please contact the provider's office to confirm that your insurance is accepted.

Dr. Robert Blair Ash, MD appears to accept the following insurance providers: Anthem Blue Cross HMO, Aetna HMO, Blue Shield of California, United Healthcare HMO, Anthem, Medicare Advantage, Providence, Health Net HMO and CIGNA HMO.

Insurance Accepted by Provider includes:

According to our sources, Dr. Robert Blair Ash, MD accepts the following insurance providers:

Anthem Blue Cross HMO

Aetna HMO

Blue Shield of California

United Healthcare HMO

Anthem

Medicare Advantage

Providence

Health Net HMO

CIGNA HMO

Ratings & Reviews

Dr. Robert Blair Ash, MD does not have any reviews yet, be the first to leave a review of Dr. Robert Blair Ash, MD here: Leave a Review

(No ratings)

Leave a Review

General Payments

These charts describe general payments received by Dr. Robert Blair Ash, MD. Doctors may receive payments for a number of reasons, including meal compensation, travel compensation, and consulting.

**Payments by Company**
AstraZeneca Pharmaceuticals LP	$5,469 IMFINZI $5,198	TAGRISSO $121	CALQUENCE $23	$127
Varian Medical Systems, Inc.	$585 TrueBeam $534	RapidPlan $37	$15
Genentech USA, Inc.	$352 TECENTRIQ $130	Avastin $123	TARCEVA $99
iCAD, Inc	$300 AXXENT SURFACE CONTROLLER $175	Axxent Controller $125
Siemens Medical Solutions USA, Inc.	$221 Varian Ethos Treatment Planning $172	TrueBeam $19	SOMATOM go.Top $16	Bravos Afterloader System $14
Other	$865 OPDIVO $218	KEYTRUDA $138	Nerlynx $112	ZAP-X RADIOSURGERY SYSTEM $109	ORGOVYX $50	Other $238

**Types of Payments**
Consulting Fee	$4,650
Food and Beverage	$2,488
Travel and Lodging	$506
Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program	$125
Education	$24

Biography

Dr. Robert Ash is a medical specialist in radiation oncology. After attending Memorial University of Newfoundland Faculty of Medicine for medical school, he completed his residency training at a hospital affiliated with The University of Western Ontario. Dr. Ash's clinical interests include radioembolization (selective internal radiation therapy), intensity-modulated radiation therapy (IMRT), and image-guided radiation therapy (IGRT). He appears to be an in-network provider for United Healthcare HMO, Anthem, and Blue California, in addition to other insurance carriers. Dr. Ash has received the following distinction: Physicians of Excellence, OCMA. His hospital/clinic affiliations include Children's Hospital of Orange County and Providence Medical Foundation. According to Providence Medical Foundation, he is currently accepting new patients at his office in Orange, CA.