PET/CT in gynecologic cancer

Anne Kiil Berthelsen,

PET & Cyclotron Unit, Dept of Radiation Oncology

Rigshospitalet,

Copenhagen University Hospital,

Denmark

1 PET scanner

2 PET/CT

1 CT-scanner

2 Cyclotrons

2 Radiochemistry Laboratories

9 Accelerators, 1 dedicated for Stereotactic Treatment

• PET/CT in Cervical cancer, diagnostic

• PET/CT in Radiotherapy planning

• PET/CT in Ovarian cancer, diagnostic

PET/CT IN THE DIAGNOSTIC PROCEDURE OF CERVICAL CANCER.

Staging of cervical cancer

• FIGO

• Clinical examination in anesthesia

• cystoscopy, urography, thorax X-ray.

Staging of cervical cancer

• No imaging of the primary tumor is included!

• No investigation of lymph nodes metastases are included!

Staging of cervical cancer

Surgical staging (stages IIB to IVA):

- 25 % para-aortic metastases

- Para-aortic nodal status is the most significant prognostic factor

Copenhagen cervical cancerPET/CT study

Results

Aim

Evaluate PET/CT in the diagnostic of cervical cancer.

STUDY

• Prospective study• 120 consecutive patients• Nov 2002- Oct 2005• cervical cancer, stage ≥ 1B• Mean age 48 years (19-81)• Written informed consent

FIGO STAGE

1B 28

1B Bulky 4

2A 7

2B 31

3A 1

3B 44

4A 5

Methods

PET/CT procedure

- GE Discovery LS PET/CT scanner

- 400 MBq 18F-FDG

- Min. 6 hours fasting

- Emission 3-5 minutes per bed position, depending on the weight of the patient.

Methods

PET/CT procedure

– CT as a diagnostic CT– 4 slice spiral CT– Intravenous contrast media injected

automatically with a 40 sec delay.– Oral contrast media 30 minutes before

scan start.– 140 kV, 80-120 mA– Arms above the head

Methods

• nuclear medicine • radiologist

ResultsSurgery

• Of the 28 operated patients, true positive metastases were found in 4 (14%).

• Most common were pelvic nodes

ResultsSurgery

• 1 false negative• A para-cervical lymph

node found at operation

ResultsSurgery

3 patients had false positive foci

– Iliac lymph node– Inguinal lymph node– Axillary lymph node– Small bone focus

ResultsRadiotherapy

Para-aortic lymph node metastases in 19 pt.

• Other distant foci in 10 of these.

• A new primary (lung cancer) in 1 pt.

Para-aortic lymph node metastases

ResultsRadiotherapy

7 false positive PET/CT

– 4 small bone lesions– 2 histiocytosis– 1 granuloma

Histiocytosis

ResultsRadiotherapy

Distant metastases – Neck– Mediastinum– Bone– Omentum– Lung– Liver– Adrenal gland

Neck node metastasisAdrenal gland metastasis

Pulmonary metastasis

Liver metastasis

Conclusion

• PET/CT is a useful tool in cervical cancer.

• 20% of the patients had more extensive disease than demonstrated with conventional staging.

PET/CT for radiotherapy

Advantages of PET/CT for RT

• Only one scanning procedure

• Precise anatomical localisation and function

Whole body PET/CT

• Improved the diagnose

• Para-aortic metastases• Iliac lymph nodes• Distant metastases

4-fields box technique

Cervical cancer Para-aortic LN

Intensity Modulated Radiotherapy IMRT

• Allows dose escalation to the target volume

• Reduce dose to organs at risk

PET/CT for Radiotherapy. What do you need?

Special flat top bed

External LAP laser system

Automatic iv contrast media

Fix point tattoo

Well educated staff

Time!!!!

PET/CT RT planning in 2005

• 157 PET/CT treatment planning scans

• 31 of these were cervical cances (20 %)

• 13 of these were treated with IMRT (42 %)

Tumour delineation on PET/CT

GTV PET (Gross tumour volume defined by PET) drawn as a ROI on each PET/CT slice and transfered to eclipse.

Delineation

GTV (radiologist)

GTV PET (Nuclear medicine)

CTV (Radiation oncologist)

Organs at risk: (Radiation oncologist)

Retroperitoneum, Bladder, Rectum, Intestine, Spinalcord, Kidney, Liver, Bone marrow

Vessels,pet pos gtv,gtv

Kidney,bladder,rectum

Retroperitoneum,intestine

Cervical cancer with PET pos LN

• PET pos LN 64 Gy

• Uterus – before IMRT 46 Gy + 35 Gy BT

• Uterus – with IMRT 50 Gy + 35 Gy BT

Tumour definition and

organs at risk

Dose plan

Dose plan. Coronal view.

Cervical cancer- remember the whole-body scan!

Conclusion

• In Radiotherapy, PET/CT optimises treatment planning by increasing information about – Staging– Viable tumour tissue

• Important for IMRT

Pelvic Mass project:

Background

• 5th most common cancer in Danish women

• 70% have advanced disease at time of diagnosis

• Today we us UL and CA-125 to measure Risk of Malignancy Index.

Aim

To improve diagnosis and staging

Compare PET/CT with– UL– Clinical investigations

• Tumour markers• CA-125• New markers

– Operative findings and histology

Pt Inclusion

• Patients with a pelvic mass

• High RMI index

• A high suspicion of malignant disease

Strategy for patient

• Clinical examination including UL

• Bloodtest

• PET/CT

• Operation

Protocol

• Started September 2004

• 165 patients in total

• Uptil now 100 pt

• Evaluated 77 pt

• Study time approximately 2 years

• Participation from other gyn/onc clinics

Benign-looking tumour. Histology: benign cyst

Fibroma

Ovarian Cancer with involment of the Spleen

Looks supicious on CT and UL- benign-looking on PET. Histology: Benign cyst

Thank you

Cervical cancer group:Annika Loft, Henrik Roed, Christan Ottosen, Lene Lundvall, Jens Knudsen, Hanne Sandstrøm, Liselotte Højgaard, Svend Aage Engelholm

Ovarian cancer group:Signe Risum, Svend Aage Engelholm, Henrik Roed, Annika Loft, Claus Høgdall, Estrid Høgdall

Radiotherapy group:Flemming Kjær Christoffersen, Henrik Roed, Håkon Nystrøm, Silke Sphan-Horn, Svend Aage Engelholm