IMRT - A New Treatment Method for Nasopharyngeal Cancer Wen-Shan Liu 1 , Hsiang-Chi Kuo 1 , Bin S. Teh 2 , E. Brian Butler 2 1 Chung Shan Medical & Dental College Hospital 2 Department of Radiation Oncology, Baylor College of Medicine

Wen-Shan Liu 1 , Hsiang-Chi Kuo 1 , Bin S. Teh 2 , E. Brian Butler 2

1 Chung Shan Medical & Dental College Hospital

2 Department of Radiation Oncology, Baylor College of Medicine

INTRODUCTION

Is conventional radiotherapy good enough for NPC? Local control T1 - T2: 80 - 90 % T3 - T4: 20 - 60 %

Local control

T1 - T2: 80 - 90 %

T3 - T4: 20 - 60 %

Grade III - IV Complications Temporal lobe necrosis: 2 - 33.3 % Hearing impairment: 3 - 30.9 % Cranial neuropathy: 0 - 4.2 %

Grade III - IV Complications

Temporal lobe necrosis: 2 - 33.3 %

Hearing impairment: 3 - 30.9 %

Cranial neuropathy: 0 - 4.2 %

Normal tissue complications Otitis media: 5 - 41.8 % Trismus: 3 - 12 % Xerostomia: 35 - 100 % Neck fibrosis: 3 - 36.4 % Osteonecrosis: 0 - 2 %

Normal tissue complications

Otitis media: 5 - 41.8 %

Trismus: 3 - 12 %

Xerostomia: 35 - 100 %

Neck fibrosis: 3 - 36.4 %

Osteonecrosis: 0 - 2 %

Three Major Issues of the NPC How to improve the local control especially for T3 and T4 patients How to reduce the post-irradiation late sequelae How to reduce the ratio of distant metastasis

How to improve the local control especially for T3 and T4 patients

How to reduce the post-irradiation late sequelae

How to reduce the ratio of distant metastasis

The potential benefit of IMRT for NPC Improve the local control especially for concave shape tumors Reduce the post-irradiation complications Reduce the rate of distant metastasis by improving the local control

Improve the local control especially for concave shape tumors

Reduce the post-irradiation complications

Reduce the rate of distant metastasis by improving the local control

Contents To present the preliminary results of IMRT for nasopharyngeal cancer To present the CT-based target defining for nasopharyngeal cancer To demonstrate the fractionation strategies for intensity-modulated radiation therapy of nasopharyngeal cancer

To present the preliminary results of IMRT for nasopharyngeal cancer

To present the CT-based target defining for nasopharyngeal cancer

To demonstrate the fractionation strategies for intensity-modulated radiation therapy of nasopharyngeal cancer

Patients and Methods Sept to Dec 2000: 13 patients Staging: T1-2, N0-2, M0 (AJCC 1997) Age: from 24 to 72 years old Male : female = 10 : 3

Sept to Dec 2000: 13 patients

Staging: T1-2, N0-2, M0 (AJCC 1997)

Age: from 24 to 72 years old

Male : female = 10 : 3

The procedures of IMRT for nasopharyngeal cancer Immobilization Imaging acquisition and contouring Dose calculation with inverse planning Quality assurance Verification the position Portal imaging with EPID IMRT

Immobilization

Imaging acquisition and contouring

Dose calculation with inverse planning

Quality assurance

Verification the position

Portal imaging with EPID

IMRT

Immobilization

Imaging acquisition and contouring

Dose calculation with inverse planning Varians Helios  planning system

Varians Helios  planning system

Dose limits of inverse planning

Inverse planning

IMRT QA and Treatment MLC Controller TPS Leaf Motion Treatment Machine Record and Verify Log File Indep. MU Calc. DMLC Port Film/ DRR Comparison Film/Ion Chamber Verification ?

NPC2: 測量值 NPC2: 運算值

NPC4: 測量值 NPC4: 運算值

Verification the treatment position by simulation

Verification the treatment position by portal imaging (EPID)

Intensity-modulated radiotherapy (IMRT)

RESULTS

Acute Reaction

Dosimetry

Response evaluation by CT scan

Response evaluation by CT scan

Response evaluation by CT scan

Response evaluation by CT scan

Discussion How to define the treatment targets? How to decide the doses to the different targets and different critical organs? Is the IMRT really better than conventional radiotherapy?

How to define the treatment targets?

How to decide the doses to the different targets and different critical organs?

Is the IMRT really better than conventional radiotherapy?

How to define the treatment targets?

How to define the treatment targets? Medial : c-spine body and pharyngeal wall Lateral : excluding parotid, sternocleido-mastoid & pterygoid Post .: tip of spinous process

Medial : c-spine body and pharyngeal wall

Lateral : excluding parotid, sternocleido-mastoid & pterygoid

Post .: tip of spinous process

How to define the treatment targets? Medial : c-spine body and pharyngeal lumen Lateral : edge of sternocleidomastoid m. or medial 2/3 Post .: tip of spinous process

Medial : c-spine body and pharyngeal lumen

Lateral : edge of sternocleidomastoid m. or medial 2/3

Post .: tip of spinous process

How to decide the doses to the different targets and different critical organs? SMART : simultaneous modulated accelerated radiation therapy, Dr. Butler and Dr. Teh, 1999 SIB : simultaneous integrated boost, Dr. Mohan and Dr. Wu, 2000

SMART : simultaneous modulated accelerated radiation therapy, Dr. Butler and Dr. Teh, 1999

SIB : simultaneous integrated boost, Dr. Mohan and Dr. Wu, 2000

SMART IMRT Schedule Primary target: 2.4 Gy per fraction Secondary target: 2.0 Gy Butler EB, Teh BS, Grant WH et al: SMART (simultaneous modulated accelerated radiation therapy) boost: A new accelerated fractionation schedule for the treatment of head and neck cancer with intensity modulated radiotherapy. Int J Radiat Oncol Biol Phys, v45, no.1, pp21-32, 1999

Primary target: 2.4 Gy per fraction

Secondary target: 2.0 Gy

Butler EB, Teh BS, Grant WH et al: SMART (simultaneous modulated accelerated radiation therapy) boost: A new accelerated fractionation schedule for the treatment of head and neck cancer with intensity modulated radiotherapy. Int J Radiat Oncol Biol Phys, v45, no.1, pp21-32, 1999

SIB IMRT Schedule Primary target: 2.2 Gy per fraction Secondary target: 1.8 Gy Mohan R, Wu Q, Maning M and Schmidt-Ullrich R: Radiobiological considerations in the design of fractionation strategies for intensity-modulated radiation therapy of head and neck cancers. Int J Radiat Oncol Biol Phys, v46, No.3, pp619-630, 2000

Primary target: 2.2 Gy per fraction

Secondary target: 1.8 Gy

Mohan R, Wu Q, Maning M and Schmidt-Ullrich R: Radiobiological considerations in the design of fractionation strategies for intensity-modulated radiation therapy of head and neck cancers. Int J Radiat Oncol Biol Phys, v46, No.3, pp619-630, 2000

Is the IMRT really better than conventional or 3-D conformal radiotherapy?

IMRT Two opposed

IMRT Two opposed

IMRT Two opposed

IMRT Two opposed

IMRT Two opposed

DVH of 3-D conformal radiotherapy

DVH of 3-D conformal radiotherapy

DVH of intensity-modulated radiotherapy

DVH of intensity-modulated radiotherapy

Lower skin reaction with IMRT technique

Lower skin reaction with IMRT technique

IMRT must be applied very carefully!

Dawson LA, Anzai Y, Marsh L et al: Patterns of local-regional recurrence following parotid-sparing conformal and segmental intensity-modulated radiotherapy for head and neck cancer. Int J Radiat Oncol Biol Phys, V46, No.5, pp1117-1126, 2000

Dawson LA, Anzai Y, Marsh L et al: Patterns of local-regional recurrence following parotid-sparing conformal and segmental intensity-modulated radiotherapy for head and neck cancer. Int J Radiat Oncol Biol Phys, V46, No.5, pp1117-1126, 2000

Thank You!