radiation oncology

1. Role of radiation in benign
conditions
Dr Purvi Rathod

2. Introduction
• Benign tumors are usually localized and have low potential for
progression, do not invade surrounding structures and do not
metastatize.
• When left untreated they can be bothersome or have secretory
effects.
• Cause secondary debilitating symptoms.
• Judicial use of radiation in some conditions can provide relief of
symptoms and good local control.

3. Radiobiology in benign diseases.
• They are not well defined in benign lesions.
• Complex of multicellular mechanisms that affect different cell types in
our body system.
• Benign lesions triggered by trauma ( keloid after piercing, heterotopic
bone after surgery.)
• Factor- cellular proliferation, fibroblast proliferation, inflammatory
changes.
• Radiotherapy inhibits cell proliferation and suppresses cell
differentiation without inducing cell death with tumoricidal doses of
radiation.

4. • Radiation causes sclerosis and obliteration of blood vessels ( used in
hemangiomas, vascular malformation).
• Radiation induces apoptosis by influencing expression of cytokines in
macrophages, leukocytes, endothelial and other cells by modulating
the inflammatory cascade.
• Low dose radiation (<12Gy) can induce anti inflammtory effects in the
endothelial cells.
• Radiosensitive cells express- pro inflammatory cytokines or tumor
necrosis factors.

5. • Radiation induced oxidative burst in macrophages and granulocytes
lead to modification of immune responses.
• Radiation suppresses the Ag-Ab reaction and helps suppress the
chronic inflammatory process.

6. Risk of second malignancy post RT

7. Indications
• Pain – due to degenerative processes in the tendons, ligaments, joint
impairing function.
• Radiation reduces the inflammation and relieves pain.
• Cosmetic appearance- facial keloids, juvenile angiofibroma, significant
effect on the self esteem.
• Large hemangiomas associated with thrombocytopenia and
coagulopathy have fatal complications, therapeutic intervention can
be life saving.
• A risk benefit analysis is a must. With potential effects of infertility
and second malignancies.

8. • brain tumors- meningioma, pituitary adenoma, craniopharyngioma,
acoustic neuroma, chordoma, glomus tumor.
• Head and neck- juvenile angiofibroma, trigeminal neuralgia.
• Functional disorder- epilepsy, Parkinson’s disease.
• bone and msk- dupuytren contracture, heterogenous bone,
osteoarthritis.
• Others- graves ophthalmopathy, pterygium, choroidal hemangioma,
desmoid tumor, keloid.

9. Benign neoplasms of brain and head neck.
1) Meningioma
• >90% benign and WHO grade I
• Symptoms- headache , other localized symptoms.
• MRI- homogenous intensely enhancing extra axial mass with or
without dural tail.
• Mx- surgery is treatment of choice.
• Active surveillance- asymptomatic patients with small meningioma.
• 67% have PR or androgen receptor, 10% ER receptors but response to
antihormonal agents is low.

11. • Radiotherapy in meningioma-
• Indications
1)In locations where complete resection is not possible.( III nerve,
cavernous sinus).
2) subtotal resection,
3) recurrent disease.
4) WHO grade II and III.
• Treat with conventional fractionated 3DCRT, IMRT, FSRT, SRS, protons
or heavy ions.
• Post op MRI co registered with treatment planning CT.

12. • For 3DCRT or IMRT-
• CTV= 1-2cm margin around GTV respecting normal tissue boundaries.
• PTV= 3-5mm boundaries to CTV.
• Benign meningioma- ptv 50 to 54 Gy in 1.8 to 2 Gy per #.
• Meningiomas are non invasive and well circumscribed, SRS and SRT
are used.
• SRS= 12 to 16 Gy in 1 or 2 #.
• Benefit of including the dural tail must be weighted against risk of
toxicity from increasing the target volumes.
• Protons and heavy ions- 56GyE in 1.8 to 2 Gy per #.

13. 2. Pituitary adenoma
• 75% are functional(secretory).
• Picoadenoma <0.3 cm, microadenoma <1cm, macroadenoma >1cm .
• Classic sign- bitemporal hemianopia due to mass effect on optic
chiasma.
• Extension to cavernous sinus, cranial nerves deficit, hypothalamus.
• Excess hormone- galactorhea, amenorrhea, diminished libido and
infertility, acromegaly, cushings disease, hyperthyroidism.
• Analysis of hormone levels, CE MRI with thin slice, tissue diagnosis.

14. • Surgery is the treatment of choice.
• Transsphenoidal approach, frontal craniotomy.
• Patients who have abnormal elevated hormone levels post surgery
need adjuvant treatment with drugs or radiotherapy.
• Pharmacotherapy- bromocriptine and cabergoline for prolactinomas,
octretide for GH adenoma and TSH adenomas, ketoconazole for ACTH
adenomas.
• Radiotherapy- recurrent tumors, persistent hormone elevation post
surgery, medically inoperable( primary treatment).
• After 2yrs of RT, GH levels stabilize quickest, slowest for TSH.
• Discontinue pharmacotherapy 1 to 3 months prior to initiation of RT
due to low sensitivity with concurrent medical treatment.

15. • 3DCRT, IMRT-
• GTV= using post op MRI with planning CT.
• CTV= 1 to 1.5cm margin to GTV.
• PTV= 3 to 5mm margins to CTV.
• Non functional adenomas= 45 to 50.4Gy in 1.8 to 2Gy #
• Secretory adenoma=50.4 to 54 Gy in 1.8 to 2 gy #.
SRS= lesions <3cm, FSRT=>3cm lesions and near critical structures.
• Non functional adenoma= 16 to 20Gy single #.
• Functional adenoma= 20 to 25 Gy single #.

16. 3. Craniopharyngioma
• Pediatric cns tumor( 5to10yrs), second peak >40yrs age.
• Benign epithelial tumors arising from remnants of Rathke’s pouch
most commonly seen in suprasellar region.
• Adamantinomatous and squamous subtypes.
• Solid and cystic pattern with “machine oil like” cystic fluid.
• Most common hormone deficiency is lack of GH.

17. • Complete resection with surgery but high rates of neurological
sequelae, visual impairment, panhypopituitarism.
• TOC= safe resection with adjuvant RT.
• 3DCRT and IMRT-
• GTV= post op residual tumor including cyst wall ( post op MRI fused
with planning CT.
• PTV= margin of 1 to 1.5cm to GTV .
• Dose= 54Gy in 1.8 to 2Gy per #.
• Proton therapy-excellent results.
• 52.2 to 54GyE in 1.8GyE per #.

18. • Reimaging ( Ct or MRI)within 2wks of treatment planning scan and
evry 2 wks thereafter.
• For large cysts that demonstrate growth during RT, weekly reimaging
is recommended.
• SRS and FSRT- 18 to 38Gy over 3 to 10 #.
• Cystic craniopharyngiomas can be managed with intralesional
radioactive isotopes using beta emitter Yttrium-90, phosphorus 32.
• 200 to 250 Gy prescribed to cyst wall.

19. 4. Acoustic neuroma
• Derived from schwann cells of neurilemma of auditory nerve.
• Can be unilateral and sporadic or bilateral associated with AD
disorder neurofibromatosis type II.
• Symptoms- hearing loss, tinnitus, vertigo.
• Can affect trigeminal neve and brain stem.
• All patients must undergo audiometry, CE MRI.
• Surgery is preferred for large symptomatic lesions.

20. • Observation is preferred in asymptomatic patients with small tumors,
serial MRI and audiometry atleast once a yr.
• Radiotherapy-
• SRS, FSRT is an option for primary treatment of AN with higher facial
nerve preservation rates compared to surgery.
• 12 to 13 Gy dose with LC 98.6% SRS, FSRT 25Gy/5#, 30Gy/10#, 50 to
55 Gy in 25#.
• Proton beam SRS has low hearing preservation ( 12GyE single #).

21. 5. Chordoma
• Slow growing midline tumors arising from embryonal notochord in
the skull base (most common), vertebral column, sacral region.
• Biopsy is a must to distinguish it from chondrosarcoma or RMS.
• Complete surgical resection is the mainstay of treatment.
• Gross total resection is often not possible.
• Some may benefit from imatinib or combination of imatinib and
sirolimus.
• Adjuvant RT indicated to reduce recurrence for skull based
chordomas.

22. • 3dcrt, imrt-
• GTV= with pre and post op mri along with planning CT.
• CTV= 1 to 2cm margin to GTV
• PTV= 3 to 5mm margin to CTV.
• Dose= 60Gy given in 1.8 to 2Gy per #.
• Proton based therapy-
• Higher doses with good results, 63 to 79.2GyE in 1.8 to 2 GyE per # .
• Carbon ion therapy- 60GyE/20# within 3wks, LCR 81% at 3yrs.
• SRS and FSRT are less established than charged particle therapy.

23. 6. Glomus tumor.
• Glomus tumor are rare benign, at bifurcation or near carotid artery,
jugular bulb ( G. Jugulare)., middle ear( G Tympanicum).
• Symptoms- headache, cranial nerve dysfunction, dysphagia, pulsatile
tinnitus, vertigo large pulsatile mass in neck.
• Episodic hypertension- secretion of vasoactive substances by tumor,
measure metanephrines in urine and serum.
• Imaging with metaiodobenzylguanidine. (MIBG scan)
• Embolization followed by tumor resection is treatment of choice.

24. • Radiotherapy is indicated in for tumors of skull base, adjuvant therapy
after STR, salvage therapy for relapse after surgery.
3DCRT,IMRT-
• Diagnostic MRI is coregistered with planning CT.
• GTV= lesion as on MRI
• CTV= 1 to 1.4cm margin to GTV.
• Dose 45 to 55Gy in 1.8 to 2Gy per #.
• SRS-
• 12.5 to 20GY # with less complications compared to conventional
therapy hence use of SRS is advocated in Glomus Jugulare.

25. 7. Juvenile nasopharyngeal angiofibroma.
• Vascularised benign tumor in head and neck, mostly developed from
sphenoethmoidal suture.
• Symptoms- recurrent epistaxis, impaired nose breathing, facial
swelling, orbital symptoms, cranial nerve deficits, headaches

26. • Surgery with embolization is the TOC in stage I to III.
• For stage V, medically inoperable, relapse after surgery, treatment
with RT.
• Fractionated IMRT is the RT technique of choice.
• Dose 30 to 50GY in 2 to 3 Gy #.

27. 8. Langerhans cell histiocytosis ( histiocytosis-
X)
• Rare disorder with higher incidence in children.
• Children have better prognosis.
• Disease is due to accumulation of cells that are phenotypically like
Langerhans skin cell and can cause tissue damage by production of
cytokines and infiltration.
• LC are myeloid dendritic cells that express the same antigens as
Langerhans Skin cells – CD1a, CD207.
• Birbecks granules on electron microscopy.

28. • It affects variety of organ systems.
• 1) single system disease- single site.
• 2) single system with multiple sites-
• 3) multisystem disease.
• In children skeletal site is MC and present with pain, mass, motion
deficit, chronic otitis (mastoid).
• They are lytic in appearance, skull is MC site.
• Cutaneous – skin of scalp, groin, resembles seborrheic dermatitis.
• Cranial- pituitary or hypothalamus, present with diabetes insipidus.
• Pulmonary- MC is adults.

29. • GIT, hepatomegaly, splenomegaly, bone marrow infiltration are other
potential sites.
• Evaluation- complete H&P, WBC with diff, water restriction test for DI,
bone scan, CT head for mastoid orbit, MRI brain for pituitary,
hypothalamus, CT chest, MRI abdomen.
• Treatment depends on the site and extent of disease.
• 1) only skeletal system- curretage, excision, intralesional steroid.
• 2) single system multifocal- corticosteroids or chemotherapy with
vinblastine.

30. • 3) skin only- nitrogen mustard and methotrexate.
• 4) multisystem- systemic therapy with prednisolone, vinblastine,
etoposide.
• Excellent response rate to nonradiotherapeutic measures hence role
of RT is limited.
• Indicated only in bony lesions with relapse after surgery, no sign of
clinical healing after other interventions, pain, compromise of critical
structures from expansile lesion ( cord compression).

31. • Collapsed vertebrae should not be irradiated unless they are painfull.
• DI must be treated with RT.
• Technique of choice- 3DCRT.
• Children (dose)- 5 to 10 GY in 1.5 to 2GY per # per day.
• Adults – higher doses 6 to 15Gy for previously untreated, 8 to 15GY in
recurrent.
• For DI target volume- hypothalamus with pituitary gland. Dose- 15 GY
in 1.5Gy #.

32. 9. Arteriovenous malformations
• AVM are widened arteries connected to normal capillaries with one
or more fistulas.
• High risk of bleeding , nonfocal symptoms- headache, nausea, focal
neurological deficit.
• Immediate cure with complete surgical resection but high risk of
itraop bleeding, CVA, ischemia, death.
• Surgery is indicated in superficial and noneloquent areas of brain.
• Embolization is not curative but reduces intra op bleeding risk and
reduces size of nidus prior to RT.

33. • RT- SRS is modality of choice.
• For deep areas of brain where surgery is not possible.
• Safe and more successful in <3cm lesion.
• Time to obliterate is 1 to 4yrs post SRS hence risk of bleeding persist
post RT.
• Dose- 16 to 24Gy #, in spinal cord 22Gy in 2#.

34. 10. Hemangioma
• Dynamic vascular tumors in proliferative or involution phase.
• Most undergo spontaneous involution .
• Treatment is needed in obstruction of vision (eyelid hemangioma),
ulceration and infection, cosmetic deformity from facial hemangioma
and high cardiac output failure.
• Treatment with local and systemic drugs, lazer therapy and surgery.
• Glucocorticoids are mainstay of systemic treatment.
• With propranolol most children show significant regression of lesion
and ability to wean off steroids without rebound.

35. • RT is indicated only when patients have exhausted all treatment
options.
• With RT response is quick.
• patient must be followed for secondary malignancy.
• MRI is useful to delineated margins.
• CTV= visible palpable lesion with margin.
• Dose- <10Gy,1 to 3Gy per #.

36. 11. Trigeminal neuralgia
• Characterised by pain along the track of the trigeminal nerve.
• Type I TN- pain is sharp, lancinating, shock like, with pain free
intervals.
• Type II TN- burning, aching, throbbing pain.
• Triggers of attack- talking, chewing, brushing teeth, cold air.
• MRI brain to rule out structural abnormalities.
• Pharmacotherapy- carbamazepine (mc drug), oxcarbamazepine,
lamotrigine, gabapentin, pimozide, tizanidine, topiramate.

37. • Microvascular decompression is the treatment of choice for medically
refractory TN.
• Other options- rhizotomy, radiofrequency ablation, glycerol injection,
balloon compression.
• RT- SRS is a successful minimally invasive procedure to treat TN.
• Fusion of diagnostic MRI with planning CT for target delineation.
• Dose- 70 to 90Gy #.
• Median time for pain relief is 1 month.
• There can be delayed onset of facial numbness.

38. 12. Epilepsy
• Recurrent seizures with unknown etiology.
• TOC is antiepileptic drugs.
• Surgery is indicated in medically refractory epilepsy. (temporal lobe
epilepsy.)
• SRS is an alternative to surgery in medically refractory epilepsy and
inoperable patients.
• Mesial temporal lobe- 24 to 25Gy # with gamma knife.
• Amygdala, hippocampus, parahippocampal gyrus- 20 to 24Gy #.
• Further study needed, role of RT not established.

39. 13. Parkinson’s disease
• Loss of dopaminergic neurons in substantia nigra.
• Mask like face, resting tremors, slow movement, muscle rigidity,
shuffling gait, dementia.
• Pharmacotherapy with dopamine agonists.
• In medically refractory disease- thalamotomy, pallidotomy, deep brain
stimulation.
• RT- indicated in poor surgery candidates refractory to medical
treatment.
• SRS- nucleus intermedius 120 to 180 Gy # with out serious
complications and success rate of 80% to 90%.

40. 14. Psychiatric disorders
• OCD, bipolar disorders, major depression.
• TOC is combination of drugs and behavior treatment.
• Surgery and deep brain stimulation in severe cases.
• RT- in OCD b/l anterior capsule radiated with SRS 120 to 140Gy .
• Further study required to establish role of RT.

41. 15. Cardiac arrhythmias
• Theoretical role of SRS for cardiac radioablation with 25Gy # at the
ectopic site traced with electro anatomic maps.
• Very challenging to target arrhythmic beat accurately.
• With simultaneous sparing of surrounding structures ( esophagus,
bronchus) with cardiac contraction and respiration.
• Only case reports available of successful treatment with SRS.

42. 16. Pterygium
• Chronic fibrovascular and degenerative process
• Arises from the conjunctival–corneal border, wing like tissue shape-
pterygum.
• Higher frequency in tropical regions.
• Redness irritation of eye, cosmetic concern, vision impairement with
astigmatism.
• Surgical excision is TOC.
• Improve local control with intra or post op mitomycin-C.

43. • RT- adjuvant treatment to surgery to prevent relapse.
• Strontium-90 , 30 Gy/10# to 60 Gy/10# once per week have been
commonly used.
• single-dose postoperative radiotherapy (25 Gy × 1) delivered within
24 hours of surgery.

44. 17. Choroidal hemangioma
• Rare vascular tumors arising from the choroid, they can be diffuse or
circumscribed.
• Often asymptomatic but can present with visual disturbances by
retinal detachment, macular edema, and retinal pigment changes.
• Diagnosed with fundus examination.
• Treatment- laser photocoagulation and transpupillary thermotherapy.
• But radiation is preferred for the treatment of diffuse CH, treat lesions
near the macula and papilla.

45. • RT- 3DCRT, protons, brachytherapy.
• 3DCRT- 18 to 20 Gy for circumscribed CH, 30 Gy for diffuse CH in 1.8-
to 2-Gy #.
• Proton- 16.4 to 30 GyE in 4#.
• Brachytherapy- Plaque brachytherapy using Co60, I125, or Ru106 has
been used to treat circumscribed lesions with a dose of 25 to 50 Gy .

46. 18. Graves ophthalmopathy
• Also called thyroid eyes.
• autoimmune disorder affecting the musculature of the orbits.
• Smoking is the greatest risk factor for the development of GO and
also predicts for a poorer response to therapy.
• proptosis, photophobia, upper eyelid retraction, periorbital edema
(accumulation of collagen and hyaluronan, which attract water),
conjunctival erythema, tearing and visual impairment.
• mc involved muscles are the inferior and medial rectus muscles.

48. • Treatment- glucocorticoids, orbital radiotherapy, and surgery (orbital
decompression, eye muscle surgery, eyelid surgery).
• Prior to surgery- thyroid function should be normalized. Radioiodine
therapy, but not antithyroid drugs, may cause worsening of GO.
• Indication of RT- inducing clinical regression, improving functional
deficits, improving cosmesis.
3DCRT-
• Both orbits, including the entire length of the extraocular muscles,
• dose of 20 Gy in 2-Gy/#.
• opposed lateral fields with the isocenter placed a few millimeters
posterior to the lenses using a beam-split technique

50. 19. Osteoarthritis
• Mc joint disorder in older people.
• Mc symptom- joint pain caused by reactive inflammation of joint
surface and joint capsule lining (synovia).
• Risk factors- age, genetic predisposition, bone fracture or joint injury
whether by an accident or overuse from work or sports, and
increased BMI.
• Treatment- Exercise, weight reduction, and joint braces, exercises that
strengthen muscles, oral analgesics, Corticosteroids.
• Surgery- for patients with severe OA, who have not responded to
noninvasive therapies., total or partial joint replacement.

51. • Role of RT- In nonsurgical candidates, low-dose RT may be considered
if pharmacotherapy has failed.
• 80% of institutions in Germany have used RT to treat OA
• median total dose was 6 Gy (range 3 to 12 Gy), with a median single
dose of 1Gy (0.25 to 3 Gy).
• pain reduction for at least 3 months, but pain management for up to
12 months was reported.
• 30% of patients, a second course of RT was used for inadequate pain
response or early pain recurrence.
• RT may provide an alternative to conventional conservative
treatment.

52. 20. Vertebral hemangioma
• 50% of hemangiomas involving the vertebral body are associated with
pain and therefore may require treatment.
• Treatment- surgical resection, transarterial embolization,
vertebroplasty, or intralesional injections
• Radiation therapy either alone or postoperatively has been successful
in reducing pain caused by vertebral hemangiomas.
• Radiation doses ≥34 Gy resulted in significantly improved pain relief. A
total radiation dose of 36 to 40 Gy in 2Gy/# is recommended.

53. 21. Desmoid tumors
• connective tissue tumors that arise from muscle fascias, aponeuroses,
tendons, and scar tissue.
• Genetic factors, trauma, and/or surgery predisposes the development
of desmoids.
• Most desmoids arise sporadically.
• MC site- trunk/extremity, shoulder girdle, buttock, abdominal wall,
intra-abdominal sites, including the bowel and mesentery.
• locally aggressive and commonly have a high rate of recurrence even
after complete resection.

54. • Observation is a option for stable, asymptomatic desmoids.
• Treatment is indicated for symptomatic patients, if there is risk to
adjacent structures, or to improve cosmesis.
• Complete surgical resection with negative microscopic margins is the
treatment of choice.
• Also treated with NSAID’s- sulindac. And Tamoxifen and imatinib.
• Role of RT- in inoperable patients, RT reduces the risk of recurrence in
patients with microscopically positive resection margins.
• Dose- for inoperable or recurrent desmoids is 60 to 65 Gy.

55. • Long term effects of RT >55Gy- grade III and IV complications,
including pathologic fractures, impaired range of motion, pain, and in-
field skin cancers.
• R0 resection is not possible, doses of 50 to 60 Gy postoperatively
should be given to improve local control.
• Not considered for intra abdominal lesion for risk of bowel injury.

56. 22. Dupuytren contracture.
• connective tissue disorders that affects the palmar or plantar fascia.
• The fourth/fifth phalanges of the hand or the first/second toes of the
foot are most commonly affected digits.
• Treatment- selective fasciectomy. But relapse is common.
• Radiotherapy is currently used in the treatment of Dupuytren’s
exclusively for early-stage patients (who have a <10-degree
deformity) and is considered standard of care for prevention of
Dupuytren progression.
• Dose- 30Gy conventional RT.

58. Thank you