**2. Treatment**

Definitive treatment modalities: The management for cancer mainly includes three treatment modalities—surgery, radiotherapy and chemotherapy. These modalities can be used individually or in combination with each other. The factors that influence choice of initial treatment for primary carcinomas of the oral cavity are dependent on the characteristics of the primary tumor (tumor factors), those related to the patient—site of the primary tumor, size (T-stage), location (anterior vs. posterior), proximity to bone (mandible or maxilla), status of cervical lymph nodes, histology (type, grade, and depth of invasion), and previous treatment, and those related to the treatment team providing care to the patient (physician factors). The ultimate goals in treatment of cancer of the oral cavity are to eradicate the cancer, preserve or restore form and function, minimize the sequelae of treatment, and prevent subsequent new primary tumors [1].

#### **2.1. Surgery**

Surgery is the mainstay of treatment for oral cancers. The goal of any oncological surgery is complete removal of the primary tumor and appropriate clearance of regional lymph nodes, while preserving the integrity of uninvolved structures.

#### *2.1.1. Management of primary lesion*

The surgical plan should involve wide excision of the tumor in all three dimensions with adequate margins (**Table 2**). This should account for histopathological shrinkage (approximately 25%) [2]. Due attention must be given specially to the third dimension which is the soft tissue/depth and generally the site of surgical failures. An examination under anesthesia should ideally always precede the excision.

Intraoperative frozen section evaluation is a very effective modality to assess the complete removal of the malignant lesion. Frozen section provides instant pathological information that can guide intra-operative surgical decision making such as adequacy of margins, identification of nodal metastases [3, 4]. However, we have literature from high volume centers

*Lower cheek flap*: This approach allows access to the mandible, lower gingiva-buccal complex, retro-molar trigone and tonsil. Depending upon the location and extent of the tumor, the deci-

Management Strategies for Oral Cancer Subsites http://dx.doi.org/10.5772/intechopen.81555 73

*Mandibulotomy*: This approach allows access to the posterior tongue, tonsil and soft palate. A paramedian mandibulotomy is preferred between the lateral incisor and canine since these teeth roots are maximally divergent. Care should be taken to remain anterior to the mental

*Pull through*: This approach is often employed for large volume tongue cancers with extension

*Commando approach*: This terminology has fallen out of favor and the term composite resec-

sion to preserve the metal nerve and the lateral mandibular periosteum is made.

into the hyoglossus muscle provided gingivolingual mucosa and alveolus are free.

• Depth of invasion and extrinsic tongue muscle involvement bad prognosticators

• Compartmental excisions are recommended for deep invasion of extrinsic tongue musculature to ensure removal of the tumor along with the in-transit lymphatics and contiguous

• Since reconstruction has direct impact on speech and swallow, following principles must

○ Prevent tethering to mandible/inter-dental stitches that will hamper with mobility

• High prevalence in Indian subcontinent due to habit of chewed tobacco consumption

• Extent of disease into the masticator space and infra-temporal fossa must be assessed on

• Caution should be exercised in estimating deeper soft tissue extent in the setting of trismus and posteriorly located tumors particularly with involvement of the retro-molar trigone area.

nerve. A step ladder osteotomy offers a better mechanical advantage.

tions are used to denote excision of tongue, tonsil and mandible.

• Notorious for neural and lymphovascular invasion

○ Maintain bulk posteriorly to prevent aspiration

Buccal mucosa/gingivobuccal sulcus/mandible:

○ Palatal contact to promote better consonant pronunciation

• Proximity to and involvement of mandible determines bony resection

• Propensity for nodal and distant metastases

*<IP_ADDRESS>. Subsite specific salient features*

• Aggressive biological behavior

• Tendency for submucosal spread

lymph nodal station [7].

pre-operative imaging

be borne in mind

○ Preserve tip

Tongue/floor of mouth:

**Table 2.** Adequacy of margins for resection of oral primary.

in India to suggest that the incremental value of frozen section analysis of margins over surgeon's gross assessment is limited when the margin is >7 mm [5]. The authors have original research work in role of crush imprint cytology for identification of nodal metastases from oral cancers with reasonable sensitivity (92%) and accuracy (88%) [6].

#### *<IP_ADDRESS>. Approaches to the oral cavity*

*Per-oral*: This approach has the following prerequisites (**Figure 1**)

*Upper cheek flap*: This approach allows access to the maxilla, upper alveolus, hard palate. Care should be exercised while raising the flap superolaterally to avoid injury to the infra-orbital nerve and to anticipate subcutaneous/cutaneous soft tissue extent of the tumor while deciding the thickness of the flap. Extensions of the flap such as the lateral rhinotomy, Weber Ferguson with or without Dieffenbach extension can be used to excise sinonasal tumors. Lateral subciliary or supra-orbital incisions can be combined to perform orbital exenteration depending upon the extent of the tumor.

**Figure 1.** Resection of squamous cell carcinoma of right lateral border of tongue by per oral approach.

*Lower cheek flap*: This approach allows access to the mandible, lower gingiva-buccal complex, retro-molar trigone and tonsil. Depending upon the location and extent of the tumor, the decision to preserve the metal nerve and the lateral mandibular periosteum is made.

*Mandibulotomy*: This approach allows access to the posterior tongue, tonsil and soft palate. A paramedian mandibulotomy is preferred between the lateral incisor and canine since these teeth roots are maximally divergent. Care should be taken to remain anterior to the mental nerve. A step ladder osteotomy offers a better mechanical advantage.

*Pull through*: This approach is often employed for large volume tongue cancers with extension into the hyoglossus muscle provided gingivolingual mucosa and alveolus are free.

*Commando approach*: This terminology has fallen out of favor and the term composite resections are used to denote excision of tongue, tonsil and mandible.

### *<IP_ADDRESS>. Subsite specific salient features*

Tongue/floor of mouth:

in India to suggest that the incremental value of frozen section analysis of margins over surgeon's gross assessment is limited when the margin is >7 mm [5]. The authors have original research work in role of crush imprint cytology for identification of nodal metastases from

*Upper cheek flap*: This approach allows access to the maxilla, upper alveolus, hard palate. Care should be exercised while raising the flap superolaterally to avoid injury to the infra-orbital nerve and to anticipate subcutaneous/cutaneous soft tissue extent of the tumor while deciding the thickness of the flap. Extensions of the flap such as the lateral rhinotomy, Weber Ferguson with or without Dieffenbach extension can be used to excise sinonasal tumors. Lateral subciliary or supra-orbital incisions can be combined to perform orbital exenteration depending upon the extent of the tumor.

**Figure 1.** Resection of squamous cell carcinoma of right lateral border of tongue by per oral approach.

oral cancers with reasonable sensitivity (92%) and accuracy (88%) [6].

*Per-oral*: This approach has the following prerequisites (**Figure 1**)

*<IP_ADDRESS>. Approaches to the oral cavity*

Negative margin >5 mm Close margin 1–5 mm

72 Prevention, Detection and Management of Oral Cancer

**Table 2.** Adequacy of margins for resection of oral primary.

Positive margin <1 mm/tumor cut through

**1.** Adequate mouth opening

**3.** Anteriorly located lesions

**4.** All resection margins accessible

**5.** Noncontiguous lymph nodal spread

**2.** Small size

	- Preserve tip
	- Maintain bulk posteriorly to prevent aspiration
	- Palatal contact to promote better consonant pronunciation
	- Prevent tethering to mandible/inter-dental stitches that will hamper with mobility

Buccal mucosa/gingivobuccal sulcus/mandible:

• For maxillary cancers extending onto hard palate, a hypothetical line extending from the medial canthus to the angle of mandible differentiates inferomedial and superolateral

Management Strategies for Oral Cancer Subsites http://dx.doi.org/10.5772/intechopen.81555 75

An elective neck dissection is now standard of care for all oral cancers [9]. The risk of regional metastases has been correlated to thickness of the tumor, site, size and histological features of the primary [10]. The dissemination of metastatic cancer to regional lymph nodes from primary cancers in the oral cavity occurs in a predictable and sequential fashion [11]. The initial spread from oral cancer occurs at Levels I, II, III. Involvement of Level IV is often implicated in tongue cancers. Isolated skip metastases to Level V are exceedingly uncommon. Some authors propose level IIa positivity as a guide to proceed for level IIB/V clearance [12]. A selective (supraomohyoid) neck dissection clearing Levels I, II, III, and IV is considered appropriate for most primary oral cancers with clinico-radiologically N0 neck [13]. The extent and of neck dissection varies according to the clinico-radiological staging of nodal disease (**Table 3**). Sentinel node biopsy has gained much interest as a reliable and oncologically safe, less morbid alternative to elective neck dissection [14]. However, requirement of resources and expertise and a reasonably steep

tumors. The former is said to have a significantly better prognosis than the later.

learning curve for accurate interpretation of results has limited its wider applicability.

**Figure 2.** Techniques for reconstruction of upper and lower lip defects.

*2.1.2. Management of neck nodes*

• Placement of the incision (midline or commissure split incision) should be based on anterior extent of the resection margin.

### *<IP_ADDRESS>. Management of mandible*

*Indications* for marginal mandibulectomy:

However, a mandibular height of minimum 1 cm is essential for bony support after marginal mandibulectomy. In situations where inferior soft tissue or bony margin does not allow this, a segmental mandibulectomy should be contemplated. Soft tissue margins are often used as surrogates to decide bony margins. Frozen section analysis of the bone marrow can alternatively be used to decide adequacy of the same [8].

*Indications* for segmental mandibulectomy:

#### *<IP_ADDRESS>.1. Lip*

#### *<IP_ADDRESS>.2. Hard palate*

• For maxillary cancers extending onto hard palate, a hypothetical line extending from the medial canthus to the angle of mandible differentiates inferomedial and superolateral tumors. The former is said to have a significantly better prognosis than the later.

### *2.1.2. Management of neck nodes*

• Reconstruction of middle third should be necessarily with free osteocutaneous flaps

**1.** For achieving adequate margin (tumor close to but not involving mandible)

rior extent of the resection margin.

74 Prevention, Detection and Management of Oral Cancer

*Indications* for marginal mandibulectomy:

tively be used to decide adequacy of the same [8].

• Squamous cancers are the most common histology

*Indications* for segmental mandibulectomy:

*<IP_ADDRESS>. Management of mandible*

**2.** Superficial bony erosion

**1.** Gross bony erosion

**3.** Edentulous mandible

**4.** Gross paramandibular disease

**2.** Prior radiation

*<IP_ADDRESS>.1. Lip*

*<IP_ADDRESS>.2. Hard palate*

common histology

surface of the soft palate.

**3.** Superficial periosteal invasion

• Reconstruction of posterior segment can be with osteocutaneous or soft tissue flaps depending upon age of the patient, disease extent and amount of remnant mandibular segment. • Placement of the incision (midline or commissure split incision) should be based on ante-

However, a mandibular height of minimum 1 cm is essential for bony support after marginal mandibulectomy. In situations where inferior soft tissue or bony margin does not allow this, a segmental mandibulectomy should be contemplated. Soft tissue margins are often used as surrogates to decide bony margins. Frozen section analysis of the bone marrow can alterna-

• Involvement of oral commissure has direct bearing on its esthetic and functional performance • While reconstruction it is important to remember that the lip should have sensation, motion, prevent drooling, permit speech and have a reasonable cosmetic appearance (**Figure 2**).

• Salivary gland malignancies are common although squamous cancers still remain the most

• Nasal endoscopy should be performed to determine extension into the nasopharyngeal

An elective neck dissection is now standard of care for all oral cancers [9]. The risk of regional metastases has been correlated to thickness of the tumor, site, size and histological features of the primary [10]. The dissemination of metastatic cancer to regional lymph nodes from primary cancers in the oral cavity occurs in a predictable and sequential fashion [11]. The initial spread from oral cancer occurs at Levels I, II, III. Involvement of Level IV is often implicated in tongue cancers. Isolated skip metastases to Level V are exceedingly uncommon. Some authors propose level IIa positivity as a guide to proceed for level IIB/V clearance [12]. A selective (supraomohyoid) neck dissection clearing Levels I, II, III, and IV is considered appropriate for most primary oral cancers with clinico-radiologically N0 neck [13]. The extent and of neck dissection varies according to the clinico-radiological staging of nodal disease (**Table 3**). Sentinel node biopsy has gained much interest as a reliable and oncologically safe, less morbid alternative to elective neck dissection [14]. However, requirement of resources and expertise and a reasonably steep learning curve for accurate interpretation of results has limited its wider applicability.

**Figure 2.** Techniques for reconstruction of upper and lower lip defects.

#### *<IP_ADDRESS>. Incisions for neck dissection*

The exact location and type of skin incision will depend on the site of the primary tumor and whether a unilateral or bilateral neck dissection is planned. Caution should be exercised to avoid tri-pointer suturing over the great vessels to safeguard from a dreaded complication of carotid blow-out. Triangular edges in the flaps are liable to undergo ischemic necrosis and should be similarly avoided. The vertical limbs in the incision should be avoided as they produce unsightly scars and contractures which produce neck morbidity.

The following are the various routinely employed incisions used for neck dissection [15, 16].

#### *2.1.3. Reconstruction*

Reconstruction after oral cancer surgery should aim at restoration of both form and function. The principle of "like for like" is a good rationale for deciding the type of reconstruction. This can be accomplished by the following: (1) primary closure, (2) split thickness skin graft, (3) vascularized cutaneous free flap, (4) regional myocutaneous flap, or (5) microvascular free

**Figure 4.** Modified radical neck dissection preserving IJV, SAN and sacrificing SCM.

**Figure 3.** Selective neck dissection preserving greater auricular nerve, sternocleidomastoid muscle (SCM), internal

Management Strategies for Oral Cancer Subsites http://dx.doi.org/10.5772/intechopen.81555 77

jugular vein (IJV), spinal accessory nerve (SAN).

**Table 3.** Extent of neck dissection for oral cancers.

*<IP_ADDRESS>. Incisions for neck dissection*

76 Prevention, Detection and Management of Oral Cancer

morbidity.

**I.** Macfee incision **II.** Crile's incision

**VI.** Apron incision

*2.1.3. Reconstruction*

Classical radical neck dissection [13, 14]

Extended radical neck dissection

**III.** Hay-Martin's incision **IV.** Schobinger's incision

**V.** Modified Conley's incision

**VII.** Modified Macfee incision

N0 1. Selective neck dissection (**Figure 3**)

dissection N+ Modified neck dissection (**Figure 4**)

1. N3 disease

1. Gross extranodal disease.

sinuses, etc.

**Table 3.** Extent of neck dissection for oral cancers.

2. Involvement of the skin or platysma.

The exact location and type of skin incision will depend on the site of the primary tumor and whether a unilateral or bilateral neck dissection is planned. Caution should be exercised to avoid tri-pointer suturing over the great vessels to safeguard from a dreaded complication of carotid blow-out. Triangular edges in the flaps are liable to undergo ischemic necrosis and should be similarly avoided. The vertical limbs in the incision should be avoided as they produce unsightly scars and contractures which produce neck

The following are the various routinely employed incisions used for neck dissection [15, 16].

Reconstruction after oral cancer surgery should aim at restoration of both form and function. The principle of "like for like" is a good rationale for deciding the type of reconstruction. This can be accomplished by the following: (1) primary closure, (2) split thickness skin graft, (3) vascularized cutaneous free flap, (4) regional myocutaneous flap, or (5) microvascular free

tion therapy, or previous selective neck dissection

2. Frozen section/crush imprint cytology for clinically suspicious nodes-SOS modified neck

2. Gross invasion of the spinal accessory nerve/internal jugular vein/sternocleidomastoid 3. Recurrent or persistent metastatic carcinoma after previous radiation therapy, chemoradia-

3. Involvement of other nonlymphatic structures like great vessels (carotid), nerves (vagus, phrenic, sympathetic plexus, etc.) muscles of neck, mandible, maxilla, infratemporal fossa,

**Figure 3.** Selective neck dissection preserving greater auricular nerve, sternocleidomastoid muscle (SCM), internal jugular vein (IJV), spinal accessory nerve (SAN).

**Figure 4.** Modified radical neck dissection preserving IJV, SAN and sacrificing SCM.

flap. A variety of free flaps consisting of skin, muscle, bone, or any combination of these tissues are available for reconstruction in the oral cavity. There is an increasing inclination towards microvascular reconstructions for oral resections in light of better functional and cosmetic outcomes [17]. To summarize, the choice of reconstruction should be guided by the anticipated postoperative morbidity, extent of resection and the available infrastructure, resources and expertise.

Indications for adjuvant radiation:

• Positive nodal metastases/multiple positive lymph nodes (>2 lymph nodes)/bilateral posi-

Management Strategies for Oral Cancer Subsites http://dx.doi.org/10.5772/intechopen.81555 79

Some oncologists practice concurrent chemoradiation for bulky or level IV/V nodal disease or

Interstitial brachytherapy represents a traditional approach for OSCC and is an alternative to external beam radiotherapy (EBRT). Brachytherapy delivers radiotherapy by positioning radioactive sources in direct proximity to the tumor target area. Brachytherapy is a feasible

• Superficial lesions (especially over lip, tip of nose where surgical resection will lead to

For selected T4 tumors where morbidity of resection is extremely high, NACT can be administered. Induction chemotherapy has been used as a biological decider for locally advanced

• Adverse pathological factors such as lymphovascular or perineural invasion

tumors, lymphovascular or perineural invasion also [20, 21].

treatment option restricted to following conditions in oral malignancies:

disease

tive lymph nodes • Extranodal invasion • Poor differentiation

• Positive surgical margins

• Positive surgical margins

• Perinodal extension

*2.2.1. Brachytherapy*

• Small tumors

• N0 nodal status

**2.3. Chemotherapy**

• Tumors away from bone

T3 /T4

Indications for adjuvant chemoradiation [19]:

considerable cosmetic deformity)

*2.3.1. Neo-adjuvant chemotherapy (NACT)*

borderline operable disease [22].

Chemotherapy has no curative potential in oral cancers.

• Recurrent tumors

• T3 /T4

#### *<IP_ADDRESS>. Tongue*

Being a very mobile organ and of paramount importance in deglutition and prevention of aspiration, reconstruction of tongue defects is a challenge (**Table 4**).

#### *<IP_ADDRESS>. Gingivobuccal-alveolus complex*

Smaller defects can be closed with local flaps such as palatal, buccal fat pad, posterior tongue flap, nasolabial flap, etc. Larger soft tissue defects should be reconstructed with FRAFF, FALT or PMMC and deltopectoral flaps depending on defect, disease and patient factors and the expertise available. Segmental mandibular defects should ideally be reconstructed with free osteocutaneous flaps like the fibular, iliac crest, scapular flap, etc. Posterior mandibular defects in old age patients can be considered for PMMC flap reconstruction. Hard palate defects can be reconstructed with dental obturators or osteocutaneous flaps.

#### **2.2. Radiotherapy**

Radiotherapy has undergone remarkable advances in the past few decades. With the advent of intensity modulated radiotherapy and image guided radiotherapy, radiation treatment delivery has become very precise with minimum damage of surrounding areas at risk [18]. Tumors of the tongue require bilateral face and neck radiation whereas buccal complex tumors warrant unilateral face and neck radiation. The primary role of radiotherapy in oral cancers is in the adjuvant setting. Upfront radiation is offered in very select cases of early small size accessible tumors (generally brachytherapy) or as a non-surgical treatment for locally advanced cancers where either surgery is contra-indicated on medical grounds.

**Table 4.** Reconstruction of tongue defects.

Indications for adjuvant radiation:

• T3 /T4 disease

flap. A variety of free flaps consisting of skin, muscle, bone, or any combination of these tissues are available for reconstruction in the oral cavity. There is an increasing inclination towards microvascular reconstructions for oral resections in light of better functional and cosmetic outcomes [17]. To summarize, the choice of reconstruction should be guided by the anticipated postoperative morbidity, extent of resection and the available infrastructure,

Being a very mobile organ and of paramount importance in deglutition and prevention of

Smaller defects can be closed with local flaps such as palatal, buccal fat pad, posterior tongue flap, nasolabial flap, etc. Larger soft tissue defects should be reconstructed with FRAFF, FALT or PMMC and deltopectoral flaps depending on defect, disease and patient factors and the expertise available. Segmental mandibular defects should ideally be reconstructed with free osteocutaneous flaps like the fibular, iliac crest, scapular flap, etc. Posterior mandibular defects in old age patients can be considered for PMMC flap reconstruction. Hard palate defects can be reconstructed with dental obturators or osteocutane-

Radiotherapy has undergone remarkable advances in the past few decades. With the advent of intensity modulated radiotherapy and image guided radiotherapy, radiation treatment delivery has become very precise with minimum damage of surrounding areas at risk [18]. Tumors of the tongue require bilateral face and neck radiation whereas buccal complex tumors warrant unilateral face and neck radiation. The primary role of radiotherapy in oral cancers is in the adjuvant setting. Upfront radiation is offered in very select cases of early small size accessible tumors (generally brachytherapy) or as a non-surgical treatment for locally advanced cancers where either surgery is contra-indicated on medi-

<30% substance loss Primary closure (some surgeons also consider leaving behind a raw surface for very

2. Pectoralis major myocutaneous flap (PMMC)/ Free anterolateral thigh flap (FALT)/

superficial small size defects)

Rectus abdominis flap

>30% tissue loss 1. Free radial artery forearm flap (FRAFF) Supple, sensate

Provide good bulk

**Table 4.** Reconstruction of tongue defects.

aspiration, reconstruction of tongue defects is a challenge (**Table 4**).

resources and expertise.

*<IP_ADDRESS>. Gingivobuccal-alveolus complex*

78 Prevention, Detection and Management of Oral Cancer

*<IP_ADDRESS>. Tongue*

ous flaps.

**2.2. Radiotherapy**

cal grounds.

Indications for adjuvant chemoradiation [19]:

Some oncologists practice concurrent chemoradiation for bulky or level IV/V nodal disease or T3 /T4 tumors, lymphovascular or perineural invasion also [20, 21].

#### *2.2.1. Brachytherapy*

Interstitial brachytherapy represents a traditional approach for OSCC and is an alternative to external beam radiotherapy (EBRT). Brachytherapy delivers radiotherapy by positioning radioactive sources in direct proximity to the tumor target area. Brachytherapy is a feasible treatment option restricted to following conditions in oral malignancies:

#### **2.3. Chemotherapy**

Chemotherapy has no curative potential in oral cancers.

#### *2.3.1. Neo-adjuvant chemotherapy (NACT)*

For selected T4 tumors where morbidity of resection is extremely high, NACT can be administered. Induction chemotherapy has been used as a biological decider for locally advanced borderline operable disease [22].

However, in candidates that undergo surgery, it must be borne in mind that resection margins must be planned taking into account the initial extent of the tumor and not the measurements of the shrunken tumor after NACT.

**References**

[1] Shah J. Head and Neck Surgery and Oncology. 3rd ed. St. Louis, MO: Mosby; 2003

Otorhinolaryngology—Head and Neck Surgery. 2016;**2**(1):17-21

neck. American Journal of Surgery. 1978;**136**(4):525-528

[6] http://www.jhnps.org. IP: <IP_ADDRESS>

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The Laryngoscope. 2015;**125**(5):E173-E179

1986;**152**:345-350

2014;**36**(10):1503-1507

2015;**51**(18):2777-2784

[2] Mohiyuddin SMA, Padiyar BV, Suresh TN, et al. Clinicopathological study of surgical margins in squamous cell carcinoma of buccal mucosa. World Journal of

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[3] Byers RM, Bland KI, Borlase B, Luna M. The prognostic and therapeutic value of frozen section determinations in the surgical treatment of squamous carcinoma of the head and

[4] van den Hoogen FJ, Manni JJ. Value of the supraomohyoid neck dissection with frozen section analysis as a staging procedure in the clinically negative neck in squamous cell carcinoma of the oral cavity. European Archives of Oto-Rhino-Laryngology. 1992;**249**(3):144-148 [5] Chaturvedi P, Datta S, Nair S, Nair D, Pawar P, Vaishampayan S, et al. Gross examination by the surgeon as an alternative to frozen section for assessment of adequacy of surgical margin in head and neck squamous cell carcinoma. Head & Neck. 2014;**36**(4):557-563

[7] Calabrese L, Bruschini R, Giugliano G, Ostuni A, Maffini F, Massaro MA, et al. Compartmental tongue surgery: Long term oncologic results in the treatment of tongue

[8] Namin AW, Bruggers SD, Panuganti BA, Christopher KM, Walker RJ, Varvares MA. Efficacy of bone marrow cytologic evaluations in detecting occult cancellous invasion.

[9] D'Cruz AK, Vaish R, Kapre N, et al. Elective versus therapeutic neck dissection in nodenegative oral cancer. The New England Journal of Medicine. 2015;**373**(6):521-529 [10] Spiro RH, Huvos AG, Gy W, et al. Predictive value of tumor thickness in squamous cancer confined to the tongue and floor of mouth. American Journal of Surgery.

[11] Shah JP. Patterns of nodal metastasis from squamous cell carcinomas of the upper

[12] Pantvaidya GH, Pal P, Vaidya AD, Pai PS, D'Cruz AK. Prospective study of 583 neck dissections in oral cancers: Implications for clinical practice. Head and Neck.

[13] Brazilian Head and Neck Cancer Study Group. Results of a prospective trial of elective modified radical classical versus supraomohyoid neck dissection in the management of

[14] Schilling C, Stoeckli SJ, Haerle SK, et al. Sentinel European Node Trial (SENT): 3-year results of sentinel node biopsy in oral cancer. European Journal of Cancer.

oral squamous cell carcinoma. American Journal of Surgery. 1996;**176**:422-427

aerodigestive tract. American Journal of Surgery. 1990;**160**:405-409

#### *2.3.2. Palliative chemotherapy*

Combination palliative chemotherapy has been documented to prolong progression free survival by few months. However, the risk benefit ratio of the disease response and systemic side effects of the chemotherapy must be critically evaluated at each stage to decide regarding continual treatment.