Key Points
- Although anatomically adjacent to one another, accumulating data suggests that, in many ways, squamous cell carcinoma of oral cavity (SCCOC) and oropharynx (SCCOP) may be distinct diseases from a biological perspective.
- Oral SCC is predominately associated with tobacco and betel nut use. On the other hand, SCCOP is increasing in incidence in recent decades due to chronic latent infections of the human papillomavirus (HPV) and appears to disproportionately affect younger people.
- The majority of patients with SCCOP have node-positive (cN+) necks at presentation, and 10-40% of patients without cN+ necks at presentation will have occult nodal metastases in both SCCOC and SCCOP. As such, management of the neck is a critical component of high quality oncologic care of these patients.
Treatment
Oral Cavity
Recommendation 1.1a
- For patients with oral cavity SCC classified as cT2-cT4, cN0 (i.e. no clinical nor radiographic evidence of metastatic spread to the neck) and treated with curative-intent surgery, an ipsilateral elective neck dissection should be performed. (Strong Recommendation; EB-H-B)
Recommendation 1.1b
- For patients with oral cavity SCC classified as cT1, cN0, an ipsilateral elective neck dissection should be performed. Alternatively, for selected highly reliable patients with cT1, cN0, close surveillance may be offered by a surgeon in conjunction with specialized neck ultrasound surveillance techniques. (Strong Recommendation; EB-I-B)
Recommendation 1.2a
- For patients with a cN0 neck, an ipsilateral elective neck dissection should include nodal levels, Ia, Ib, II, and III. An adequate dissection should include at least 18 lymph nodes. (Strong Recommendation; EB-H-B)
Recommendation 1.2b
- An ipsilateral therapeutic selective neck dissection for a clinically node-positive (cN+) neck should include nodal levels Ia, Ib, IIa, IIb, III and IV. An adequate dissection should include at least 18 lymph nodes. Dissection of level V may be offered in patients with multi-station disease. (Moderate Recommendation; EB-I-B)
Recommendation 1.3
- In patients with a cN+ contralateral neck, a contralateral neck dissection should be performed. In patients with a cN0 contralateral neck, an elective contralateral neck dissection may be offered in patients with a tumor of the oral tongue and/or floor of mouth that is T3/4, or approaches midline. (Moderate Recommendation; EB-I-B)
Recommendation 2.1a
- Adjuvant neck radiotherapy should NOT be administered to patients with pathologically node negative (pN0) or a single pathologically positive node (pN1) without extranodal extension after a high-quality neck dissection, unless there are indications from the primary tumor characteristics, such as perineural invasion, lymphovascular space invasion, or a T3/4 primary. (Moderate Recommendation; EB-I-B)
Recommendation 2.1b
- Adjuvant neck radiotherapy should be administered to patients with oral cavity cancer and pN1 who did not undergo a high-quality neck dissection (as defined in recommendation 1.2b). (Moderate Recommendation; EB-I-B)
Recommendation 2.2
- Adjuvant neck radiotherapy should be administered to patients with oral cavity cancer and pathologic N2 or N3 disease. (Strong Recommendation; EB-I-B)
Recommendation 2.3a
- Adjuvant chemoradiotherapy using intravenous bolus cisplatin (100mg/m2 every 3 weeks) should be offered to patients with oral cavity cancer and extranodal extension in any positive node, regardless of the extent of the extranodal extension and number or size of involved nodes, and no contraindications to high-dose cisplatin. (Strong Recommendation; EB-H-B)
Recommendation 2.3b
- Concurrent weekly cisplatin may be administered with postoperative RT to patients who are considered inappropriate for standard high-dose intermittent cisplatin after a careful discussion of patient preferences and the limited evidence supporting this treatment schedule. (Moderate Recommendation; EB-I-B)
Recommendation 3.1
- Elective neck dissection is the preferred approach for patients with oral cavity cancer who require management of the clinically negative neck as outlined in recommendation 1.1a. Elective radiotherapy to a non-dissected neck (50-56 Gy in 25-30 fractions) may be efficacious and should be administered if surgery is not feasible. (Moderate Recommendation; EB-I-B)
Recommendation 3.2
- For patients who have undergone ipsilateral neck dissection only and are at substantial risk of contralateral nodal involvement (e.g. tumor of the oral tongue and/or floor of mouth that is T3/4 or approaches midline), contralateral neck radiotherapy should be administered to treat potential microscopic disease. (Moderate Recommendation; EB-I-B)
Oropharynx
Recommendation 4.1
- Patients with lateralized oropharyngeal carcinoma who are being treated with upfront curative surgery should undergo an ipsilateral neck dissection of levels II-IV. An adequate dissection should include at least 18 lymph nodes. (Moderate Recommendation; EB-I-B)
Recommendation 4.2
- Patients with lateralized oropharyngeal cancer who have neck dissection concurrently or before transoral endoscopic head and neck surgery should have ligation of at-risk feeding blood vessels to reduce the severity and incidence of post-operative bleeding. (Moderate Recommendation; EB-L-B)
Recommendation 4.3
- Patients with tumors extending to the midline tongue-base or palate or involving the posterior oropharyngeal wall should have bilateral neck dissections performed unless bilateral adjuvant radiotherapy is planned. The multidisciplinary team should discuss with patients the potential functional impact of bilateral neck dissection and post-operative adjuvant radiation therapy with or without chemotherapy.(Moderate Recommendation; EB-I-B)
Recommendation 5.1
- A non-surgical approach should be offered to patients with cN+ disease who have either unequivocal extranodal extension into surrounding soft tissues or carotid artery or cranial nerve involvement. (Moderate Recommendation; EB-I-B)
Recommendation 5.2
- Patients with biopsy-proven distant metastases should not undergo routine surgical resection of metastatic cervical lymph nodes. (Strong Recommendation; EB-I-B)
Recommendation 6.1a
- If PET/CT scan at ≥12 weeks after completion of radiation/chemoradiation shows intense FDG uptake in any node, the patient should have a neck dissection if feasible. If PET/CT shows no nodal FDG uptake, and the patient has no abnormally enlarged lymph nodes, the patient should not have neck dissection. (Strong Recommendation; EB-H-B)
Recommendation 6.1b
- Patients who complete radiation/chemoradiation and have anatomic cross-sectional imaging (CT or MRI scans) at ≥12 weeks post therapy showing resolution of previously abnormal lymph nodes should not have neck dissection. (Strong Recommendation; EB-I-B)
Recommendation 6.2
- If PET/CT scan at ≥12 weeks shows mild FDG uptake in a node ≤1 cm or a persistently enlarged node ≥1 cm without either mild or intense FDG uptake, that patient may be followed closely with serial cross-sectional imaging or PET/CT, with neck dissection reserved for clinical or radiographic concern for progressive disease. (Moderate Recommendation; EB-I-B)