RADIOTHERAPY MANAGEMENT OF ORAL CANCER

2. RADIOTHERAPY MANAGEMENT
OF ORAL CANCER
Dr Lubna Arif
OMFS Resident

3. • The non surgical management of head and neck cancer has markedly
changed over the last two decades with the development of new
surgical approaches and novel radiotherapy technologies.

4. INDICATIONS OF RADIOTHERAPY
• Organ sparing Definitive primary radio and chemotherapy
• Palliative Radiotherapy
• Adjuvant radiotherapy
• Chemoradiotherapy

5. Organ sparing Primary Definative Radio chemo therapy
• Primary radical radiotherapy is given with the intention of cure and
has been used as an alternative to surgery to spare important organ
and preserve function.
• Usually given ta a relatively high dose and with a more protracted
course.
• This approaches were initially used for laryngeal preservation, oro-
pharyngeal primaries, especially base of the tongue and tonsil oscc.

6. Palliative Radiotherapy
• This can be used for treating incurable, recurrent local disease,
metastatic disease, patient who are unfit for surgery or radical radio
therapy.
• The aim of palliative treatment is not cure but to improve Quality of
life.
• Palliative treatment can be very effective in reducing pain, shrinking
tumor masses and stopping bleeding.
• The doses in palliative radiotherapy tend to be lower than those given
for radical treatment and yet bearable for patient.

7. Adjuvant radiotherapy
• This can be given after surgery to reduce any residual microscopic
disease.
• Indication for Adjuvant radiotherapy
• Major risk factors
Positive and close margins
Extracapsular spread
• Minor risk factors
Two or more lymph nodes
Perineural and peri vascular invation
T3 /T4 tumors
DOI > 5mm
Tumor spillage during surgery

8. Chemoradiotherapy
• Chemotherapy by itself is not curative and are usually combined with primary
radiotherapy for maximizing organ preservation.
• This is achieved by tumoricidal effect of chemotherapy and its action as a radio-
sensitizer on the cancer cells making them more susceptible to radiation.
• Single agent cisplatin is commonly given at day 1,22 and 43, 100 mg/mm2 i.v.
• Patients with renal impairment are not good candidate for cisplatin and are
usually prescribed with cetuximab (a monoclonal antibody, EGFRI) along with
radiotherapy.
• Neo-adjuvant or induction chemotherapy act as a marker for response to later
concurrent chemoradiotherapy, if this neoadjuvant chemotherapy fails to
produce a significant response this can be an indication that later concurrent
chemoradiotherapy will also fail.

9. Methods of Radiotherapy
• Conformal External beam radio therapy:
 this was most common mode of radiotherapy before IMRT
In this Multiple beams can be focused on the centre of the tumor and these
beams can be sculpted using either thick alloy blocks or wedges.
• Intensity Modulated radiation therapy
It gives three dimensional distribution of radiation doses, allowing for much
tighter conformity around the tumor and much reduced dose reaching near
by organ at risk.
It reduce Late xerostomia by sparing one of the parotid gland
Concerns: Radiation bath to more tissues and radiation induced more cancers
in near future.

10. • Brachytherapy
oIt is defined as “treatment at short distance” and is produced by either
directly inserting live sources or by stiching in silicon tubes.
oThese inducers are placed in a line with a margin of 1 to 2 cm.
oTreatment are usualy twice daily, 5-10 minutes (for 10 days) per exposure
with an intervening mandatory nontreatment period to allow for normal
tissue recovery.
oIt may give high doses of radiation to adjacent mandible,particularly for
larger tumors resulting in a significant risk of ORN.

12. Radio therapy doses and fractionation
• Effect of radiation will depend on
1. Total dose
2. The number of fraction it is delivered in
3. Time period in which it is given
• Conventionally standard dose of Radio therapy is 70 Gray (Gy) in 35 daily
factions at 2 Gy per fraction, treating 5 days per week for 6-7 consecutive
weeks.
• Radiotherapy should be complete in 6 weeks, because after 6 weeks of
radio therapy remaining tumor cells enter a phase of accelerated
repopulation.
• This may increase acute radiation side effects but they would be
temporary.

13. Altered fractionation Regimens
• Two main types
1. Accelerated Fractionation
2. Hyperfractionation
• ACCELERATED FRACTIONATION:
Same total dose over shorter period of time, by giving more than 1 fraction
per day with a gap of 6-8 hours
By Reducing the overall time decreases the opportunity for cancer cells to
repopulate.

14. • Hyperfractionation
• Higher total dose but lower individual Fractions are given twice per day.
• For Definative radiotherapy (1.2 Gy per fraction, twice a day, 5 days a week to 81.6 Gy per 68
fractions for 7 weeks) yielded the best long term results with respect to locoregional control and
overall survival
• As Fraction size reduces, there is in general a reduction in radiotherapy late side effects.

15. PRERADIATION PATIENT MANAGEMENT
• Cessation of smoking
• Alcohol cessation
• dental evaluation
• Performance status

16. Complications of Radiotherapy
• Early
 Fatigue, hair loss, Radiation sickness
 Mucositis, loss of taste
 Xerostomia
 Skin reaction(erythema, dry or wet desquamation)
 Candida infection
 Haematopoitic suppression

17. Late complications
• Permanent xerostomia
• Skin changes(atrophy of skin and
fibrosis)
• Decaying of teeth
• ORN
• Trismus, pharyngeal stenosis
• Carotid artery stenosis
• Radiation retinopathy, cataract
• Radiation induced malignancy-
thyroid cancer
• Carotid blowout syndrome
• Orophyrengocutaneous fistula

18. • MUCOSITIS
Develops in 2 or 3 week because Oral mucosa replaces its self every two weeks.
It may worsen during 1st two weeks after completion of radiotherapy but gets better after 6
weeks.
Symptomatic relief
Orabase/gel care
Lignocain lollipops
Oral hygiene sponges
Amifostine is a radio protector given i.v daily during radiotherapy which protects normal cells.
• Skin Reaction and Fibrosis
Starts with in first two weeks
Erythma (grade 1) Dry desquamation (Grade2) Moist desquamation (Grade 3)
Ulceration/necrosis
Patients undergoing radiotherapy should avoid wet shaving,any trauma to skin and perfumed
toiletries.
Flamazinc cream can be used after completion of radiotherapy.

19. • Pain
• When pt comes with complain of pain presenting in an unusual manner , who
has previously been pain free, never underestimate that!
• Pain can be the first symptom of Recurrence can result from direct nerve
infiltrate.
• C.T/ MRI or PET C.T is preferred in such scenario
• Pain management
NSAIDS
Week opoids (codeine)
Morphine suspensions
Gabapentin, ketamine, Tricyclic antidepressants.

20. • Trismus
• This is due to radiation induced fibrosis involving the jaw muscles.
• Start jaw exercise i.e with wooden tongue depressor or therabite during
Radiotherapy, there is less chance of improvement if exercise begins after
completion of radiotherapy

21. • Xerostomia
o Salivary gland tissue is more radiosensitive than other mucosal soft tissue and acute
xerostomia may develop if pboth parotid are in radiation volume.
o IMRT can delineate and protect both parotid, if total parotid dose is less than 24 Gy.
o Xerostomia is often permanent if parotid tissues receives dose >30Gy.
o Treating established xerostomia is difficult not only because there is decrease salivay flow
but thicker viscosity of saliva.
Multiple sips of water
Lemon or orange lozenges
Artificial saliva
Mouth moisturizing gel
Pilocarpine (5mg, TDS)
A novel experimental approach is being tried to surgically remove salivary gland out of
the radiotherapy treatment for later transplantation,

22. Osteoradionecrosi (ORN)
• Late radiotherapy effect may occur years after treatment because osteoblast
death has occurred secondry to the previous radiotherapy.
• More common in mandible than in maxilla because of rich blood supply of
maxilla.
• Presentation can range from asymptomatic area of exposed bone, to an infected,
painful necrotic area with bony sequestra and pathological fracture.
• Remove all the decayed, periodonticaly compromised teeth atleast 2 weeks
before radiotherapy, prevent any dental extraction for atleast a year after
radiotherapy, oral hygiene maintanence, fluoride gel application.
• If large area of bone is involved and bony sequestra have have developed then
surgery is indicated to remove the source of further infection and reconstruct the
mandible.
• Hyperbaric oxygen dives have been used in attempt to reoxygente the hypoxic
bony tissue.

24. • Carotid artery rupture
Occurrence is more likely in patients who have tumor recurrence after neck
dissection and adjuvant radiotherapy.
More common after re-irradiation for tumor recurrence and almost always
fatal
• Depression and psychosocial morbidity and Poor quality of life
Depression because of Disfigurement and altered body image,pain, loss of
function with speech and swallowing and anxiety about tumor recurrence.

25. Future Directions
• Reduction of toxicity
(1) substitution of alternative agent chemotherapy or omitting chemotherapy altogether.
2) reducing the volume of tissue electively radiated
(3) reducing the dose of radiation prescribed
(4) applying new/emerging technologies in radiation delivery
• The RTOG is investigating whether substituting cetuximab for cisplatin in patients
receiving organ-preservation RT yields equivalent disease outcomes with less
toxicity.
• new technologies, such as proton RT, can be used in conjunction with other
approaches to further improve normal tissue sparing from high-dose radiation.
• sparing of critical structures (such as the salivary glands, swallowing musculature,
mandible, oral cavity) that when overexposed, can lead to severe acute and long-
term side effects associated with conventional RT techniques.

26. References
1)Lin, A. (2018). Radiation Therapy for Oral Cavity and Oropharyngeal Cancers
Dental Clinics of North America, 62(1), 99–109. doi:10.1016/j.cden.2017.08.007
2)Book of maxillofacial surgery by Peter A.Brennan, 3rd edition volume 1
3)Current therapy in oral and maxillofacial surgery by shahrokh C. Bagheri