oncology

2.  ANATOMY & PATTERN OF SPREAD
 CLINICAL PRESENTATION
 MANAGEMENT: GENERAL
RADIATION THERAPY
OTHER CANCER-DIRECTED
PALLIATION

3.  Low incidence: <1% of malignant tumors
 3-4% of all H&N cancers.
 More common >40 yrs.
 M:F::3:2.
 Cancers of maxillary sinus are twice as common as those of
nasal cavity, sphenoid, ethmoid.
 Squamous cell cancers commonest.
 Etiological correlation.
- Adenoca (ethmoid, nasal cavity) – carpenters, saw mill
workers.
- Sq Ca – Nickel, thorotrast
 No significant association has been observed with cigarette
smoking & alcohol consumption.
 HPV-6 / HPV-11 demonstrated in 10% of squamous cell
carcinoma nose & pns.

4.  Paranasal sinuses are group of air-filled
spaces surrounding nasal cavity.
 Named according to the bones in which they
are located.
 Anterior group: Ant Ethmoid
Maxillary
Frontal
 Posterior group: Sphenoid
Post Ethmoid

5.  Largset, pyramidal shaped
 Dimensions: 3.0x2.7x1.5 cm
 Volume: 15 cm2
 4 walls: nasal (medial),
orbital (roof),
facial (anterolateral), infratemporal
(posterolateral).
 Base: nasal cavity
 Apex: zygomatic bone.
 Roof contains infra-orbital canal.
 Roots of 1st & 2nd molar may project
into infra-temporal fossa.
 Pterygopalatine fossa lies
immediately behind maxillary sinus.
 Secretions drain by mucociliary
clearance into middle meatus via
hiatus semilunaris.

6.  Ohngren’s line: Theoretical
plane dividing each maxillary
sinus into supra-structure &
infrastructure.
 A line that is drawn from the
angle of mandible to the
medial canthus.

7. Antero-lat
infrastructure:
Erodes through GBS &
gingiva.
Presenting in oral
cavity.
Palate, tissue of cheek
Poster-lat infrastructure:
infratemporal fossa,
posterior to the
pterygopalatine fossa and
pterygoid plates, masseter
ms, temporalis ms.
Middle cranial fossa: foramen rotundum,
foramen lacerum, pterygoid canal;
Nasopharynx : sphenopalatine foramen;
Infra-temporal fossa: pterygomaxillary fissure;
Orbital apex : inferior orbital fissure
Orbit, ethmoid ,
air cells.

8. • Divided into 3 groups:
anterior, middle, posterior.
• Medially: nasal cavity
• Laterally: orbit.
• Lamina papyracea:
incomplete parous bone
seperates sinus from orbit.
• Fovea ethmoidalis:
seperates from ant cranial
fossa.
• Closely related to optic
nerves laterally & optic
chiasm posteriorly.

9. Orbit: Lamina
papyracea
Ant cranial fossa:
Fovea ethmoidalis
Nasal cavity:
medially
STRUCTURE INVOLVED %
I/L nasal cavity 76%
Maxillary sinus 56%
Orbit 53%
Sphenoid sinus 35%
Ant cranial fossa 32%
Frontal sinus 18%
Nasopharynx 12%
C/L ethmoid sinus 12%
Jiang GL, Morrison WH, Garden AS, et al. Ethmoid sinus
carcinomas: natural history and treatment results. Radiother
Oncol 1998;49:21-27.

10. • Asymmetric located in inner
& outer tables of frontal
bone.
• Posterior: ant cranial fossa
• Inferiorly: sphenoid sinuses
• Inferolaterally: orbit

11.  Sparse capillary lymphatic supply.
 < 20 % of tumors.
 The risk of lymphatic metastases is related to extension of
tumor outside the sinus to areas with capillary lymphatics.
 Tumors invading the anterior nose and cheek have a higher
risk of lymphatic spread than those contained within the
sinuses.
 Maxillary sinus tumors that invade the oral cavity and
involve the buccal mucosa, maxillary gingiva, or hard
palate may spread to the submandibular and level II nodes.
 Lymphatic spread is more common in tumors invading
adjacent mucosal surfaces such as the nasopharynx from
where can metastasize to retropharyngeal nodes to level II
nodes.
 Squamous & poorly differentiated tumours:17-20%
 Adenoca, adenoid cystic & mucoepidermoid ca:4-5%

12. Cancer Metastasis Biologic Basis and Therapeutics

13.  Most commonly associated with
minor salivary gland tumors,
especially with adenoid cystic
carcinomas.
 Olfactory nerve: through
cribriform plate to ant cranial
fossa.
 Infraorbital nerve & nerves that
run through the superior orbital
fissure : into the cavernous sinus
or middle cranial fossa.
 Maxillary nerve: through foramen
rotundum,

14. MAXILLARY SINUS:
T: Tx: Primary tumor cannot be assessed
T0: No evidence of primary tumor
Tis: Carcinoma in situ
T1: Tumor limited to maxillary sinus mucosa with no erosion / destruction
of bone
T2: Tumor causing bone erosion / destruction : extension to hard palate,
middle nasal meatus; except to post wall of maxillary sinus & pterygoid
plates
T3: Tumor invades: bone of the post wall of maxillary sinus, subcutaneous
tissues, floor or medial wall of orbit, pterygoid fossa, ethmoid sinuses
T4a: Tumor invades ant orbital contents, skin of cheek, pterygoid plates,
infratemporal fossa, cribriform plate, sphenoid, frontal sinuses
T4b: Tumor invades: orbital apex, dura, brain, middle cranial fossa, cranial
nerves other than maxillary division of trigeminal(V2), nasopharynx, clivus

15. NASAL CAVITY AND ETHMOID SINUS:
Tx: Primary tumour cannot be assessed
T0: No evidence of primary tumour
Tis: Carcinoma in situ
T1: Tumour restricted to any one subsite, with or without bony
invasion
T2: Tumour invading two subsites in a single region,or extending to
involve an adjacent region within the nasoethmoidal complex,
with or without bony invasion
T3:Tumour extends to involve medial wall or floor of orbit,maxillary
sinus, palate or cribriform plate
T4a: Tumour invades any of the following:anterior orbital contents,
skin of nose or cheek, minimal extension to anterior cranial
fossa, pterygoid plates, sphenoid or frontal sinus
T4b: Tumour invades any of the following: orbital apex, dura, brain,
middle cranial fossa, cranial nerves other than V2, nasopharynx
or clivus

16. NODAL STAGING:
NX: Regional nodes cannot be assessed
N0: No regional lymph node metastasis
N1: Metastasis in a single ipsilateral lymph node ≤3 cm in greatest
dimension
N2a: single ipsilateral LN, > 3 cm but ≤ 6 cm
N2b: multiple ipsilateral LN, none > 6 cm
N2c: bilateral or contralateral LN, none > 6 cm
N3: Metastasis in a lymph node > 6 cm in greatest dimension
DISTANT METASTASIS:
M0: No distant metastasis
M1: Distant metastasis

18.  Maxillary sinus:
 Oral symptoms: 25-35%:
• Pain, trismus, alveolar ridge
fullness, erosion
 Nasal findings: 50%
• Obstruction, epistaxis, rhinorrhea
 Ocular findings: 25%
• Epiphora, diplopia, proptosis
 Facial signs:
• Paresthesias, asymmetry
 Classic Triad of advanced disease:
• facial asymmetry
• tumor bulge in oral cavity
• nasal mass
 Ethmoid sinus:
 Nasal symptoms: 74%
• Nasal obstruction, discharge,
epistaxis
 Orbital symptoms: 35%
• Diplopia, orbital pain, vision
loss, proptosis, inner canthus
mass, tearing
 Early symptoms of nasal cavity and paranasal sinus tumors are vague and
mimic sinusitis symptoms; thus the diagnosis of malignancy is often
delayed for months.
 Distant metastases on initial presentation are even less frequent, with a
reported incidence of less than 5%.

19.  Biopsy:
 Punch / Endoscopic
 Endoscopic preferred.
 Mucosal biopsy from palate to be
avoided
 Caldwell – Luc procedure for biopsy
only in select cases
 Imaging (mandatory) to assess
the extent of disease:
 Computed Tomography (CT) and / or
Magnetic
 Resonance Imaging (MRI)

20. • Bone erosion:
Key areas include the bony orbital walls,
cribriform plate, fovea ethmoidalis, posterior wall
of the maxillary sinus, pterygopalatine fossa, the
sphenoid sinus, and the posterior table of the
frontal sinus.
• 85% accuracy
• Difficult:
Periorbital involvement
Difficult to differentiate between:
Tumor vs. Inflammation vs. secretions

21. • 94% accuracy
• MRI is excellent for:
- Intracranial extension
- Perineural Spread
- Post surgery setting
Tumor Secretion Inflammation
T1 Intermediate No enhancement Low signal
T1 with contrast Diffuse
enhancement
No enhancement Low signal
T2 Intermediate
signal
High signal High signal
T2 weighted MRI T1 weighted MRI

22. Nasal cavity
& ethmoid
T1-2 N0
SURGERY
PORT
Def RT
T3-4 N0
SURGERY
PORT
Def RT/
CT+RT
T1-4 N+
RESECTION +
NECK
DISSECTION
PORT
/CT+RT
CT+RT
Surgery is the treatment of choice for almost all sinonasal
malignancies. The goal of surgery is to achieve en bloc
resection of all involved bone and soft tissue with clear
margins while maximizing the cosmetic and functional
outcome.
Surgical approaches for early stage disease:
1.Midfacial degloving
2. Lateral rhinotomy
3. Endoscopic Transnasal
4. Medial maxillectomy with ethmoidal clearance
Indications for PORT:
1. Margin +ve
2. PNI +ve
Unresectable tumors:
1.Gross infiltration of infratemporal fossa.
2.Pterygoplatine fissure involvement
3.Involvement of dura and intra-cerebral
extension of squamous carcinoma.
4.Cavernous sinus involvement
5.Involvement of sphenoid.
6.Extensive soft tissue and skin infiltration.
7.Bilateral orbital involvement
Surgical approaches for late stage disease:
1.Total Maxillectomy with ethmoidectomy
2.Combined Craniofacial approach for lesions
reaching / involving the cribriform plate.
3.Orbital exenteration if eye involved.

23. MAXILLARY
SINUS
T1-2 N0
SURGERY
PORT
Def RT
T3-4 N0
SURGERY
PORT
Def RT/
CT+RT
T1-4 N+
RESECTION +
NECK
DISSECTION
PORT
/CT+RT
CT+RT
Surgical approaches for early stage disease:
1.Infrastructure maxillectomy
2.Maxillectomy with orbital plate
preservation
PORT criteria:
1. Close margin
2. PNI +ve
3. Adenoid cystic
Surgical approaches for late stage disease:
1.Total Maxillectomy with Ethmoidectomy
2.Orbital exenteration if eye involved.
3. Combined craniofacial resection

24. DEFINITIVE
ADJUVANT
PALLIATIVE
But post-operative RT preferred:
• Preoperative radiation increases the infection rate
and the risk of postoperative wound complications.
• Preoperative radiation may obscure the initial extent
of disease=surgery can not remove the microscopic
extensions of the tumor.
Sr
no.
Author Period n Survival
end
point
(yrs)
Survival
rate(%)
Pre-op Post-
op
1 Jesse 1952-61 41 3 45 37
2 Tabb & barrance 1958-68 54 5 32 12
3 Hu et al 1958-74 50 5 64 26

28. RADIATION
TECHNIQUE
CONVENTIONAL
2D
BRACHYTHERAPY
IMRT
CONFORMAL
3D
PROTON BEAM
THERAPY

29.  Consent
 Pre-planning audit
 Pre-RT evaluation:
1.Ophthalmic evaluation : Documentation of visual acuity,
fundoscopy and visual field (perimetry) is important both in the
management of the disease as well for comparison post-treatment.
2.Dental checkup
3.Audiometry
4.Endocrinological evaluation : pituitary hormone level evaluation
5.Nutritional status assessment

30.  Supine on flat couch.
 Arms by the side of body
 Patient’s neck should be in neutral position or slight extension. Avoid
over extension.
 Patients should be asked to look straight ahead to avoid rotating the
lens or retina, particularly if the orbital cavity is included in the
treated volume.
 A mouth bite is used to depress the tongue and oral cavity away
from the treated volume and reduce acute morbidity.
 Wax plugs in the nostrils are used if the tumour extended inferiorly
in the nasal cavity to enable a more uniform dose distribution.
 Rubber traction should be used to pull shoulders towards foot end
 Precautions:
• Check if patient is comfortable
• See if base plate touches indexer
• Easy, comfortable for patient & daily set-up

31.  SUPRASTRUCTURE TUMOURS
 Three field technique
 1 anterior and bilateral fields (5° posterior tilt) and 45-
60° wedges)
 2:1 or3:1 weighted in favor of anterior beam
 INFRASTRUCTURE TUMOURS
 Anterior & lateral wedge pair(usually 45°) with 5°
posterior tilt
 Bilateral fields: tumors extending to hard palate

32. Above the crista galli (to encompass the ethmoid). In absence of orbital
invasion, at the lower edge of the cornea to cover the orbital floor.
1 cm below the floor of the sinus
1 to 2 cm (or
more if
necessary)
across the
midline
(cover
contralateral
ethmoidal
extension).
1 cm
beyond the
apex of the
sinus or
falling off
the skin
When there is no gross involvement of the orbit,
the cornea, lens & lacrimal gland are shielded
from the anterior field.
If there is disease in the orbit, cornea is spared
by cutting out the cast and treating with the eyes open.

33. Follows the floor of anterior
cranial fossa
Behind
the lat
canthus
parallel
to the
slope of
face
Covers the
pterygoid platesAngled 5-10 degree posteriorly so that the exit
beam avoids the opposite eye.
Optic chiasm & hypothalamus are shielded from
the lateral field.
Hard palate

34.  Limited lesions of nasal
cavity/reduced fields for
ethmoid sinus: Field edge is
placed at medial limbus.
 Field should be reduced with
great caution because of
subclinical extension of
tumor through lamina
papyracea.
 Upper lateral walls of
ethmoid are parallel,
inferiorly & posteriorly they
diverge to conform to cone
shaped orbit, thus some
postero-inf ethmoidal cells
also gets shielded.

36. FIELD ARRANGEMENT FOR MAXILLARY SINUS

39. FIELD ARRANGEMENT FOR ETHMOID SINUS

41.  More often used due to close approximity to critical
structures
 Position:
 Supine with arms by the side with neck slightly hyperextended
 Intraoral stent
 Immobilization:
• Thermoplastic mould to immobilize head & shoulders(if neck is to
be treated)
 Initial simulation:
• Lasers alignment with feducial markers as close to the target as
possible.
• I.V contrast (2ml/kg) given.
 Imaging:
• CT based :A CT scan is performed with 3 mm slices from 2 cm
superior to the superior orbital ridge to the hyoid bone (but
extended to include the low neck if neck nodes are to be treated).
• The whole head should be imaged if non-coplanar beams are to be
used in the treatment plan.

42.  Delineation of target volume based on
 Physical examination
 Pre- treatment imaging :
• Fused CT-MRI images useful
• To define optic pathway
• To differentiate retained secretions from residual tumor
• To delineate pre-op tumor volume
 Intraoperative findings:
• Tumor extension in relation to critical structures
• Ease of resection
 Pathological findings:
• Positive margins
• Perineural invasion

43.  GTV
• Where resection is not possible or has been incomplete, the GTV
is outlined.
• For pre-op cases: gross tumor volume is delineated.
 CTV
• Defining the CTV is the most important step
• Encompass all the initial sites of disease(pre-op GTV)
• Mucosa of adjacent compartments of sinonasal complex with a
10mm margin (where no good bony barrier to invasion exists) e.g
: masticator space, cribriform plate, infraorbital fissure).
• For most tumours, the CTV will include the ipsilateral maxillary
sinus and nasal cavity and the ethmoid sinuses bilaterally.
• The radiation portals should include neural pathways up to the
cranial nerve ganglion at the base of the skull in adenoid cystic
carcinomas and high-grade lesions with extensive perineural
invasion.

44.  PTV
• The CTV is expanded isotropically (usually by 3–5 mm) to form
the PTV.
 OARs
• include the lenses, lacrimal glands (in the superolateral orbit
and upper eyelid), optic nerves and chiasm, spinal cord,
brainstem and pituitary gland.
 PRV
• These structures can be expanded (in particular the optic nerves)
by 2–3 mm to create a PRV to account for systematic and random
errors.

45.  For maxillary sinus tumours
 Ipsilateral maxillary sinus ,nasal cavity & bilateral
ethmoid sinuses.
 Consideration should be given to including the
pterygopalatine and masticator space.
 When a maxillary tumour has invaded inferiorly, the
hard palate should be included in the CTV so as to allow
a 10 mm margin around original disease.

46. Practical essentials of IMRT –K.S. Clifford Chao

48.  For ethmoid sinus tumours
 Bilateral ethmoids with sphenoid sinus.
 Where initial disease came close to the orbit or invaded the lamina
papyracea, the CTV should include that portion of the medial and inferior
orbital walls.
 The orbital cavity should be included in the CTV if the orbital wall has
been breached by tumor or if tumor has grown superiorly through the
inferior orbital fissure.
 Where a craniofacial excision has been carried out, the CTV should
extend 10 mm superior to the cribriform plate or 10 mm superior to
initialsites of disease, whichever is greater.

67.  Elective neck RT is not routinely recommended
 Sinonasal cancers primarily drain into the retropharyngeal
(Rouviere’s), submandibular (Ib), jugulodigastric (II), and
periparotid lymph nodes.
 Elective nodal irradiation for squamous carcinoma &
undifferentiated tumours
 Retropharyngeal nodes: if disease close to or invades
nasopharynx
 If cervical nodes are to be treated: include intraparotid
nodes, level Ib and superior level II nodes
 In post-op cases with neck dissection,if multiple nodes
involved± extracapsular extension

68.  Superior border: slopes up from the horizontal ramus of
the mandible anteriorly to match the inferior border of the
primary portal posteriorly.
 Anterior border: just behind the oral commissure.
 Posterior border: at the mastoid process.
 Inferior border : at the thyroid notch (above the
arytenoids

69.  The commonest beam arrangement:
an anterior beam to provide most of
the dose with an ipsilateral or
bilateral wedged lateral beams added
to provide extra dose to the posterior
part of the PTV.
 MLCs are used to shape each beam to
the PTV.
 The lateral fields have their anterior
border behind the lens and can be
angled 5° posteriorly to avoid exiting
through the contralateral lens.

70.  The course of the optic nerves becomes
more medial at the posterior part of the
orbital cavity as they exit through the
optic canal. At this point, the nerves
commonly overlap the PTV.
 If there is high risk of local recurrence,
(which could itself cause blindness) 55
Gy can be accepted to one optic nerve
(TD 5/5:50Gy) .
 Two-phase technique : The whole PTV is
treated to 50 Gy. Then the MLCs are
moved to ensure the optic nerve doses
remain acceptable.

82.  IMRT provides a more
conformal dose distribution
to the unusual PTVs.
 A non-coplanar arrangement
of three to five sagittal
midline beams with right and
left lateral beams avoids
entry or exit of beams
through the eyes and provides
a uniform dose distribution.
 Where the PTV overlaps the
optic nerve, there must still
be either an acceptance of
increased risk of blindness or
a reduction in PTV coverage.

87.  Pre-op cases
 50Gy/25 fractions over 5-6 weeks
 Post-op cases
 56-60Gy/28-30 fractions over 6 weeks
 Radical cases/residual disease
 66Gy/33 fractions over 7 weeks
 Palliative cases

88. OARs TD5/5(Gy) TD 50/5(Gy)
Optic nerves 50 65
Optic Chiasm 50 65
Retina 45 65
Brainstem 50 65
Temporal Lobe 58 68
Lacrimal Gland 25 30
Lens 10 18
Parotid gland 26 46

89.  Dry eye syndrome leading to chronic
keratitis & iritis.
 Xerostomia.
 Nasal cavity synechiae.
 Skin, mucosal late effects.
 Visual impairment.
 Radiation retinopathy.
 Cataract.
 Brain necrosis.
 Osteoradionecrosis.

90. Conclusion:1. IMRT provided improved tumor target
coverage as compared to 3D-CRT.
2.Significant sparing of optic structures & other
normal tissues, including brain stem.
3. Inverse planning IMRT provided best treatment
for all PNS carcinomas.

91.  :ACUTE
TOXICITY
IMRT 3D CRT P VALUE
Dermatitis 75% 97.6% p=0.003
Mucositis 62.5% 97.6% p<0.001
Headache 45% 82.9% p=0.002
Xerostomia 37.5% 90.2% P<0.001
Conjunctivitis 70% Not scored
Dry eye 30% Not scored
•n=127
•No grade 3-4
toxicities with
IMRT
•No keratitis,
double vision,
photophobia with
IMRT
LATE
TOXICITY
IMRT 3DCRT p Value
Skin 7.7% 23.7% p=0.05
Mucositis 30.7% 73.7% p<0.001
Xerostomia 12.8% 34.2% p=0.03
Dry eye 7.7% 31.6% p=0.007
Dirix et al;IJROBP 2010

92. PTB characteristics:
1. rapid fall off at the distal end of
the Bragg peak.
2.Sharp lateral penumbra.
3. Depending on energy, depth,
delivery, provides better coverage.
Conclusion: PTB is a promising treatment option for
unresectable PNS malignancies.

93. Conclusion:
 Intraoral mold-based HDR brachytherapy can be used for the
treatment of tumors involving the maxillary antrum in patients
in whom insertion is possible through a previous maxillectomy.
 A favorable dosimetric profile with dose reduction factors of 4-
43% in critical organs