Techniques and challenges in

radiotherapy of head and neck

cancersSouthern Medical clinic experience

DR MILIND KUMAR

CONSULTANT ONCOLOGIST

Scope of presentation

Overview of head and neck cancer & Radiotherapy

role

Contouring & radiation planning guidelines followed

at SMOC

SMOC experience (Rapidarc in Head and neck

patients)

Management of head and neck cancers

Early stage (Stage I Stage II)—(Single modality)

Surgery or radiotherapy alone usually suffice

Advanced stage(Stage III Stage IV)– (Multimodal)

Surgery followed by post op RT or concurrent chemoradiation

Radiotherapy vs surgery

Multiple sessions –70Gy/35#/7 weeks vs one OT session

Acute side effects—skin reactions, mucositis, pain, fungal infection

Late side effects– loss of taste, xerostomia, dental caries, skin fibrosis.

Organ preservation—speech, swallowing

Weight loss during RT

Radiotherapy rationale

Ionizing radiation– free radicals damage DNA of tumor

While dividing tumor cells undergo apoptosis and cell death

Differential effect on normal tissues and they are less rapidly dividing as

compared to malignant tissues.

Radiotherapy want to focus on GTV-Gross tumor volume

CTV-Clinical target volume for subclinical disease

PTV-CTV + margin to account for daily set up errors and intra-fraction motion

Chemotherapy in head and neck cancers

It is usually used in combination with radiotherapy (sequential or

concurrent).

It has a role in organ / voice preservation (in laryngeal / hypopharyngeal

cancers) and in oropharyngeal cancers.

In select patients chemotherapy can be used for palliating symptoms.

Techniques and machines for RT

2D RT

3DCRT

IMRT

Rapidarc/ VMAT

Sterotactic body RT

Interstitial brachytherapy

MRI/PET based RT planning

Radiotherapy work flow

Initial diagnosis---tissue diagnosis ---Surgical evaluation—MDT discussion

Oncology consult—Diagnosis, investigations, staging and manangement planning

Radiation Simulation- CT with immobilization mask

Dosimetry—Identification and contouring organ at Risk

Radiation oncologist—Identification and contouring GTV/CTV

Dosimetry and Physicist—Planning, approval with RO, Quality assurance (patient specific checks)

Treatment delivery –Radiation therapists

Image guided verification of treatment delivery (CBCT/KV/MV image correction)

Weekly reviews with RO (Weight/ FBC/ local exam/ analgesia)

Daily reviews with oncology nurse, dietitian, Counsellor as need arises.

Contouring details

OAR marked:

Spinal cord

Parotid

Oral cavity

Lacrimal glands

Orbits/ optic apparatus

Larynx

Contouring notes

Nasopharynx case contouring

Anterior tongue (post op) contouring

Larynx contouring

Dose recommendations

Gross disease

70Gy/33#/7 ½ weeks High risk CTV

60Gy/33#/7 ½ weeks Intermediate risk CTV

54Gy/33#/7 ½ weeks Low risk CTV

Post op radiotherapy

66Gy/33#/6 ½ weeks for close/ positive margin

60Gy/30#/6 weeks if margins clear

Dose constraints achieved

Rapidarc planning and delivery

Recurrent adenoid cystic maxilla with

ethmoid extension

Image guidance-Treatment delivery

CBCT-Weekly CBCT

CBCT on demand if weight loss >10%, if mask is loose/ not fitting well

Kv-Kv imaging Daily done for matching.

Adaptive RT planning—In case of significant weight loss –CBCT –correlated with

planning CT scan and enables to re-CT sim and re-plan.

Ca hypopharynx post 23# CBCT

Radiation toxicities -Management

Radiation induced skin reactions-Saline dressings, do not bandage, povidone –

iodine, flamazine

Radiation induced mucositis- anbesol, magic mouthwash, soda bicarb gargles

Analgesia- Tramacet, liquid morphine

Weight loss- High protein diet sheet, daily monitoring by oncology nurses

SMOC experience

32 patients of head and neck cancers/ radiation

Nov 2015- Aug 2017 experience after commissioning of Rapidarc ix

All patients received VMAT –RA

Post op 60Gy-66Gy/30-33#

Radical 70Gy/35#/7 or 70Gy/33#/7 ½ weeks with SIB technique

60Gy/30# 60Gy/33#

54Gy/33#

SMOC experience

32 patients of head and neck cancers/ radiation

Nov 2015- Aug 2017 experience after commissioning of Rapidarc ix

All patients received VMAT –RA

Post op 60Gy-66Gy/30-33#

Radical 70Gy/35#/7 or 70Gy/33#/7 ½ weeks with SIB technique

60Gy/30# 60Gy/33#

54Gy/33#

Demographics

Females- 12/32 (37.5%)

Males- 20/32 (62.5%)

Age 50 and less: 9/32 (28%)

Age 50-70: 17/32 (53%)

Age 70 and above: 6/32 (19%)

Pie Chart showing ratio from females to males

FemalesMales

37.5%62.5%

Pie Chart showing Age bracket for Head and Neck Patients

Age 50 and lessAge 50 - 70Age 70 and above

28.0%19.0%

53.0%

Site distribution

Carcinoma oral cavity – 9

Carcinoma larynx– 9

Carcinoma oropharynx -4

Nasal cavity/ Nasopharynx/ salivary glands /Acoustic neuroma--2 each

Unknown primary,, hypopharynx-1 each

02468

10

Stage distribution

Clinical Pathological

T1- 1 3

T2- 5 7

T3- 5

T4- 6

N1- 1

N2- 2

N3-3

Recurrence/ residual/ margin positive: 5

Chemotherapy

Neoadjuvant chemo-10

Neoadjuvant and concurrent chemo- 9

Concurrent chemo only: 14

Neo Chemo

Neo and ConChemoCon ChemoOnly

Outcomes –Telephonic FU

NED- 23/32 (72%)

Alive with Local recurrence -3 (9%)

Metastatic disease- 1(3%)

Defaulted RT-1(3%)

Death-4 (13%)

Pie Chart Showing Outcomes

NED

Alive with local

Metastatic

Defaulted RT

Death

Our challenges

Timely diagnosis

Timely referral to higher centre and institution of appropriate treatment

PEG insertion pre-RT

Dental prophylaxis

Weight loss-CBCT-Adaptive RT.

Social issues-compliance

Financial constraints—SMARA charity supportive.

Thank you

Teachers/ patients/ Team @ SMC