WellSpring Oncology

Tomotherapy

WellSpring Oncology

Improving radiation technology from radium and cobalt to image guided IMRT (Tomotherapy) and stereotactic radiosurgery (Cyberknife)

CT scan and sometimes a PET scan are obtained at the time of simulation

CT images (or fusion with PET scans) are then imported into the treatment planning computer to develop sophisticated targeting plans

Advantages of using image guided IMRT with the Tomotherapy technology

1. Because the beam angles are not limited it is possible to generate extremely complex and sophisticated computer plans

2. Because a CT is taken just prior to each treatment, the set up can be very precise and accurate, and if the tumor is shrinking, the fields can be adjusted during the course of treatment (called Adaptive Radiotherapy)

3. Specific sites1. Bone Mets

2. Brain tumors

3. Breast Cancer

4. Colon and Rectal Cancer

5. Esophagus

6. Gynecologic Cancers

7. Head and Neck

8. Lung

9. Prostate

Bone Metastases

Bone Metastases to the Spine

Involved vertebrae on the left and normal on the right

Kidney cancer in the spinal vertebrae surrounding the cord, and appearance after radiation…is it possible to safely radiate further?

Spinal Cord Syndrome

Dose reconstruction for cord compressions retreatments using helical tomotherapyS.L. Mahan, C. Ramsey IJROBP Volume 60, Issue 1, Pages S640-S641 (September 2004)

patients with cord compressions that had received previous radiation therapy were imaged and treated on a HI-ART helical tomotherapy system dose calculations for no image guidance, the mean increase in spinal cord dose was 86.4% making treatment delivery impossible without image-guidance.

Dose calculations were also made considering image guidance. These doses represent what should have been delivered using daily MVCT imaging. The mean increase in spinal cord dose was 5.2% making fractionated treatment delivery to 30 Gy possible even with minimal immobilization.

Treating Multiple Sites at the Same Time is Possible with Tomotherapy

Brain Tumors

Whole brain irradiation

Whole brain radiation

The response or benefit from whole brain radiation takes several weeks to months

Memory – stem cell areas of the brain that should be avoided with radiation

May be possible to protect memory areas and still hit brain mets using Tomotherapy

Breast Cancer

Typical technique for external beam

Radiation beam skims over the surface of the chest wall, ribs and luring

Internal doses of radiation

surface doses of radiation

Computer generated breast radiation

Tumor site in breast

lung

lung

Spinal cord

heart

breast

Computer generated anatomy images that will identify all the important structures to be sure the radiation covers the area of breast cancer and limits the dose to other areas

Viewed from the side, the radiation stops before hitting the lung

Typical CT Scan after Lumpectomy for Radiation Planning, sometimes fluid collects at the surgery site (seroma) and sometimes the surgeon places clips to mark the area

clip

clip

seroma

Boost target

heartlung

lung

Radiation boost targets the high risk area, identified by the lumpectomy incision, or the seroma or surgical clips if placed

Helical Tomotherapy Planning for Left-Sided Breast Cancer Patients With Positive Lymph Nodes: Comparison to Conventional Multiport Breast TechniqueGoddu. IJROBP 2009;73:1243

The tomotherapy plans provided better dose conformity and homogeneity than did the three-dimensional plans for treatment of left-sided breast tumors with regional lymph node involvement, while allowing greater sparing of the heart and left lung

Cancer of the colon and rectum

Side Effects of Pelvic Radiation

Radiation fields

Radiation may hit the small bowel causing some cramps, diarrhea and fatigue

Case Study: Recurrent Colon Cancer with Unresectable Mesenteric Mass

Recurrent Mass surrounded by loops of normal bowel , so technically difficult to treat with conventional radiation

cancer

bowel

bowel

Using Tomotherapy we can better target the cancer and limit the dose to normal structures

Radiation dose cloud

Radiation dose cloud

Computer generated images of anal cancer

Tomotherapy for Anal Cancer

Tomotherapy for anal cancer, high dose to anus and groin nodes, while avoiding the bladder and femurs

Esophagus Cancer

PET Scan = Cancer in Lower Esophagus

PET Scan Images are used to construct radiation target in the treatment planning computer

PET Scan Images are used to construct radiation target in the treatment planning computer

Actual patient treatment images on the Tomotherapy machine

Small cancer in very elderly patient, the PET used to develop small highly targeted TOMO fields

Gyn Cancers

Uterine cancer can spread to lymph nodes

Radiation for advanced cervix cancer involving both pelvic and para-aortic nodes

Tomotherapy for Advanced Cervix Cancer

Head & Neck Cancer

CT-Pet Anatomysmall cancer in the front of the tongue (oral tongue)

mandible normal tongue

throat (pharynx)

spinespinal cord

salivarygland normal

lymph nodes

Cancer in Base of Tongue

PET Scan used to create radiation target

PET Scan , showing cancer in right tongue

Computer generated reconstruction, the target area is in red

Cancer (blue) surrounded by large field low dose radiation and then high dose boost field

Tomotherapy

Shrinking field technique, the first phase covers a large area and the final boost phase is more targeted

Low risk parotid gland tumor (in red) may be possible to keep the radiation zone (blue) as small as possible , computer plan

Low risk parotid gland tumor, then using Tomotherapy to ensure coverage of the tumor on the left, but avoiding going too deep and hitting normal parotid on other side

Since Tomotherapy takes a CT scan daily prior to radiation it is often possible to observe the tumor shrinking during the course of the radiation

Seeing the cancer shrink during a course of Tomotherapy. Nasopharynx cancer after just 8

treatments

Cancer mass Cancer massBlue = radiation target

Squamous cell carcinoma in upper jaw behind left eye treated with Tomotherapy

CT scan at 6 months

cancer

Radiation zone

For patients with dental work, a conventional CT (kV) will have artifact obscuring the anatomy that can be eliminated using the Tomo CT images (MV)

Lung Cancer

PET/CT Lung Cancer Image

Computer generated images will show how close the cancer is to other important structures (like the spinal cord, the heart and the liver, and how much normal lung is near

Using CT scans the computer can generate the target for a cancer in the upper part of the lung

Using CT scans the computer can generate the target for a small cancer growing inside the trachea

Computer generated images to target the tumor

Tomotherapy images showing the radiation zone in red surrounds the cancer area (in blue) and limits the dose of radiation that hits the normal lung, heart or spinal cord

Lung cancers shrink slowly during the radiation,

this picture from the daily Tomo image shows good regression only half way through the course of radiation

CT Scan prior to radiation Tomo image after only 19 treatments

cancer cancer

Radiation and chemotherapy for NSCL, the mass may shrink significantly during the course of radiation

Adaptive Radiotherapy – adjusting the radiation target during treatment as tumor shrinks

Tomotherapy Plan at start

Tomotherapy Plan at finish

Dose as a Function of Lung Volume and Planned Treatment Volume in Helical Tomotherapy Intensity-Modulated Radiation Therapy-Based Stereotactic Body Radiation Therapy for Small Lung Tumors

Joseph M. Baisden, M.D., Ph.D IJROBP Volume 68, Issue 4, Pages 1229-1237 (15 July 2007)

Tomotherapy can be used for highly targetted intense radiation (radiosurgery)

Tomotherapy used for lung metastases

PET Scan showing complete remission of the cancer in the left lung at 7 months

PET scan showing near complete remission, 2 months after radiation alone for NSCL

PET scan showing degree of tumor shrinkage 6 weeks after completion chemoradiation for NSCL lung cancer (the tumor will continue to shrink for weeks to months)

Prostate Cancer

Cancer occurs along the outside edge of the prostate just under the capsule

Cancer occurs along the outside edge of the prostate just under the capsule

bladder

Radiation zone

prostate

rectum

Goal = radiation zone precisely around the prostate cancer

With Tomotherapy the beam can hit the target (nodes) in the upper abdomen and avoid the bladder and small intestine and lower in the pelvis hit the prostate, nodes and seminal vesicles and still avoid the bladder and rectum

Significant movement of the prostate gland based on daily gas in rectum

Planned target

Rectal gas

No Rectal gas

Planned target, missed badly if rectal gas pushes the prostate forward

Significant movement of the prostate gland based on daily gas in rectum

Initial computer target for prostate (red circle) would have badly missed the target if no adjustments were made based on the amount of rectal gas

Importance of daily CT targeting on Tomotherapyand adjusting the treatment daily

Very little bowel gas on initial study and the dose (red) targets the prostate gland closely

large bowel gas on later treatment day and the dose (red) will cover half the rectum if an adjustment is Not made

If no adjustment was made

Actual treatment on Tomotherapy

Using Tomotherapy to tightly target the prostate with very little radiation hitting

the bladder or rectum

Tomotherapy is particularly useful in men with hip replacements where the metal creates artifacts in normal kv CT

Dose as a function of liver volume and planning target volume in helical tomotherapy,

intensity-modulated radiation therapy–based stereotactic body radiation therapy for hepatic metastasisInternational Journal of Radiation Oncology, Biology, Physics   01 October 2006 (Vol. 66, Issue 2, Pages 620-625)

TomoTherapy can be used for many other sites, e.g. liver metastases