London Dec 2013

Patient selection for adjuvant treatments in salivary gland tumors

Vincent GREGOIRE, MD, PhD, Hon. FRCR Radiation Oncology Dept. Head and Neck Oncology

Program & Center for Molecular Imaging, Radiotherapy and Oncology, Université Catholique de Louvain, St-Luc University Hospital, Brussels,

Belgium

London Dec 2013

Epidemiology

Salivary Gland Tumors •0.3-3% of all malignant tumors •4-6% of all Head & Neck malignancies •80% of salivary gland tumors arise in the parotid gland

Malignant salivary gland tumors •0.6 - 1.0 new cases/100,000 inhabitants per year •1-3% of Head & neck tumors •≈ 25% of parotid tumors are malignant •≈ 50% of submandibular gland tumors are malignant •≈ 80% of minor salivary gland tumors are malignant

High grade mucoepidermoid C

London Dec 2013

Histological subtypes: malignant T

Shah et al., 2012

London Dec 2013

TNM staging (major salivary glands)

AJCC staging, 7th edition

Primary tumor (T) Tx: primary tumor cannot be assessed T0: no evidence of primary tumor T1: tumor 2 cm or less without extraparenchymal extension T2: tumor more than 2 cm but no more than 4 cm without

extraparenchymal extension T3: tumor more than 4 cm and/or tumor having extraparenchymal

extension T4a: tumor invades skin, mandible, ear canal, and/or facial nerve T4b: tumor invade skull base and/or pterygoid plates and/or encases

carotid artery Extraparenchymal extension is clinical or macroscopic evidence of invasion of soft

tissue; microscopic extension alone does not constitute extraparenchymal extension for classification purposes

London Dec 2013

TNM staging (major salivary glands)

AJCC staging, 7th edition

Regional lymph nodes (N) NX Regional lymph nodes cannot be assessed N0 No regional lymph node metastasis N1 Metastasis in a single ipsilateral lymph node, ≤ 3 cm in greatest dimension N2a Metastasis in a single ipsilateral lymph node, > 3 cm but not > 6 cm in greatest dimension N2b Metastasis in multiple ipsilateral lymph nodes, none > 6 cm in greatest dimension N2c Metastasis in bilateral or contralateral lymph nodes, none > 6 cm in greatest dimension N3 Metastasis in a lymph node, > 6 cm in greatest dimension Distant Metastasis (M) MX Distant metastasis cannot be assessed M0 No distant metastasis M1 Distant metastasis

London Dec 2013

Treatment options

• Surgery • Radiotherapy

London Dec 2013

Surgery: primary tumor

Parotid gland • Superficial parotidectomy • Total parotidectomy • Extended total parotidectomy • Radical parotidectomy • Extended radical parotidectomy Submandibular gland • Submandibulectomy

London Dec 2013

Post-operative radiotherapy for malignant tumors

Shah et al., 2012

Memorial Sloan Kettering Institute (n=2807): tumor grade

London Dec 2013

Post-operative radiotherapy for malignant tumors

Memorial Sloan Kettering Institute (n=2807): tumor site

Shah et al., 2012

London Dec 2013

Post-operative radiotherapy for malignant tumors

Shah et al., 2012

Memorial Sloan Kettering Institute (n=2807): tumor histology

London Dec 2013

Post-operative radiotherapy for malignant tumors

Shah et al., 2012

Memorial Sloan Kettering Institute (n=2807): tumor stage

London Dec 2013

Post-operative radiotherapy for malignant tumors

Dutch Head and Neck Oncology Cooperative Group (n=666)

Terhaard et al., 2009

London Dec 2013

Post-operative radiotherapy for malignant tumors

Dutch Head and Neck Oncology Cooperative Group 1984-1985 (n=538)

Terhaard et al., 2005

R2 surgery R1 surgery

R2 surgery + RxTh R0 surgery R1 surgery + RxTh R0 surgery + RxTh

London Dec 2013

Neck management

Risk factor for nodal metastasis

• Histology and grading, e.g. high grade vs low grade, SCC, salivary duct carcinoma, undifferentiated carcinoma

• T-stage • Extraparenchymal extension • VII nerve palsy

London Dec 2013

Neck management

High risk of occult metastasis

Low risk of occult metastasis / unknown

Node-positive Node-negative

MRND ± RxTh* SND ± RxTh* ± RxTh?

Pre-operative assessment

* Multiple nodes and/or extracapsular rupture

London Dec 2013

Post-operative radiotherapy for malignant tumors

Dutch Head and Neck Oncology Cooperative Group 1984-1985 (n=538)

Terhaard et al., 2005

10-y

ear a

ctua

rial r

egio

nal c

ontro

l (%

)

Surgery Surgery ± RxTh Surgery Surgery

± RxTh

London Dec 2013

Post-operative radiotherapy for malignant tumors

• T3-T4 tumors • Close surgical margins (e.g. deep lobe, facial nerve) • Microscopically positive margin (R1) • High grade tumors • Node positive neck (>pN1 and/or extracapsular

extension) • Perineural infiltration • Recurrent tumor (including pleomorphic adenoma)

London Dec 2013

IMRT for parotid gland tumors

Left parotid ADC Dose: 30 x 2.0 Gy

PTV

Right parotid

Spinal cord

Inner ear

London Dec 2013

VIIa

Xb

VIII

IX

II

Ib

London Dec 2013

Normal tissue dose constraints IMRT for parotid gland tumors

DAHANCA, 2013

London Dec 2013

Post-operative radiotherapy for malignant tumors

Dutch Head and Neck Oncology Cooperative Group 1984-1985 (n=538)

Terhaard et al., 2005

5-ye

ar lo

cal c

ontro

l

London Dec 2013

Primary radiotherapy for malignant tumors

Dutch Head and Neck Oncology Cooperative Group 1984-1985 (n=538)

Terhaard et al., 2005

London Dec 2013

Primary radiotherapy for malignant tumors

± 1985

London Dec 2013

Primary radiotherapy for malignant tumors

Jensen et al., 2012

Hadron Therapy (Carbon ions) for adenoid cystic carcinoma

50 Gy photon IMRT + 24 GyE Carbon

London Dec 2013

Primary radiotherapy for malignant tumors

Schulz-Ertner et al., 2005

Hadron Therapy (Carbon ions) for adenoid cystic carcinoma: retrospective comparison with photon IMRT

IMRT + C-boost (n=29)

IMRT (n=34)

Loco

-reg

iona

l con

trol (

%)

London Dec 2013

Summary – key points

• Primary management is surgery • Postoperative radiotherapy (IMRT, ≈ 60 Gy) is

recommended for high risk patients • Isolated neck recurrences are rare and nodal

irradiation is indicated in pN+ patients • Radical RT (66-70 Gy) can be used in inoperable

cases • Carbon ions may be recommended for inoperable

adenoid cystic carcinoma