Comment: This recent clinical practice guideline from ASCO provides recommendations and their supporting evidence for many of the important questions relating to management of the neck in oral and oropharyngeal squamous cell carcinomas. Most notably, with growing evidence that elective neck dissection improves disease-free and overall survival in patients with clinically node-negative oral cancers, the expert panel recommends neck dissection for all patients with clinically node-negative oral squamous cell carcinoma, with the option of close observation in conjunction with neck ultrasound only for “selected highly reliable patients with cT1” tumors. —Andres Bur, MD
What are evidence-based recommendations for the management of the neck in patients with squamous cell carcinoma (SCC) of the oral cavity and oropharynx?
Bottom Line: For oral cavity cancers, clinical scenarios focused on the indications for and the hallmarks of a high-quality neck dissection, indications for postoperative radiotherapy or chemoradiotherapy, and the question of whether radiotherapy alone is sufficient elective treatment of an undissected neck compared with high-quality neck dissection. For oropharynx cancers, clinical scenarios focused on hallmarks of a high-quality neck dissection, factors that would favor operative versus nonoperative primary management, and clarifying criteria for an incomplete response to definitive chemoradiation for which salvage neck dissection would be recommended (see Table 1, below).
Background: Head and neck cancer (HNC) remains a significant global public health problem, with more than 450,000 new diagnoses worldwide each year. For patients with HNC, the presence of cervical lymph node metastases is associated with diminished overall survival. As squamous cell carcinoma of oral cavity (SCCOC) and oropharynx (SCCOP) comprise the majority of these cancers, and effective management of neck disease improves disease-specific and overall survival, these clinical practice guidelines were developed to clarify the guiding principles of managing the neck for these patients
Methods: The American Society of Clinical Oncology convened an expert panel of medical oncology, surgery, radiation oncology, and advocacy experts to conduct a literature search, which included literature published from 1990 to 2018.
Summary: The literature search identified 124 relevant studies to inform the evidence base for this guideline. Six clinical
scenarios were devised—three for oral cavity cancer and three for oropharynx cancer—and recommendations were generated for each one.
Citation: Koyfman SA, Ismaila N, Crook D, et al. Management of the neck in squamous cell carcinoma of the oral cavity and oropharynx: ASCO clinical practice guideline (published online ahead of print February 27, 2019). J Clin Oncol. doi: 10.1200/JCO.18.01921.
Table 1
Oral Cavity
Recommendation 1.1a. For patients with SCCOC classified as cT2 to cT4, cN0 and treated with curative-intent surgery, an ipsilateral elective neck dissection should be performed.
Recommendation 1.1b. For patients with SCCOC 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.
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.
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 multistation disease.
Recommendation 1.3. In patients with a cN+ contralateral neck, contralateral neck dissection should be performed.
Recommendation 2.1a. Adjuvant neck radiotherapy should not be administered to patients with pN0 or a single pN1 without extranodal extension after high-quality neck dissection, unless there are indications from the primary tumor characteristics.
Recommendation 2.1b. Adjuvant neck radiotherapy should be administered to patients with oral cavity cancer and pN1 who did not undergo high-quality neck dissection.
Recommendation 2.2. Adjuvant neck radiotherapy should be administered to patients with oral cavity cancer and pathologic N2 or N3 disease.
Recommendation 2.3b. Weekly cisplatin may be administered with post-op radiotherapy to patients who are considered inappropriate for standard high-dose intermittent cisplatin.
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 to IV. An adequate dissection should include at least 18 lymph nodes.
Recommendation 5.1. A nonsurgical 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.
Recommendation 5.2. Patients with biopsy-proven distant metastases should not undergo routine surgical resection of metastatic cervical lymph nodes.
Recommendation 6.1a. If PET/ CT scan at 12 or more weeks after completion of radiation/chemoradiation shows intense FDG uptake in any node, the patient should undergo 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.
Recommendation 6.1b. Patients who complete radiation/chemoradiation and receive anatomic cross-sectional imaging at 12 or more weeks post-therapy that shows resolution of previously abnormal lymph nodes should not undergo neck dissection.
Recommendation 6.2. If PET/CT scan at 12 or more weeks shows mild FDG uptake in a node of 1 cm or less or a persistently enlarged node of 1 cm or more without either mild or intense FDG uptake, that patient may be observed closely with serial cross-sectional imaging or PET/CT, with neck dissection reserved for clinical or radiographic concern for progressive disease.
The full recommendations are available online.