The impact of paratracheal lymph node metastasis in squamous cell carcinoma of the hypopharynx

Abstract

The aim of this study was to analyze the prevalence and prognostic importance of paratracheal lymph nodes in squamous cell carcinoma of the hypopharynx. A retrospective review of 64 previously untreated patients with squamous cell carcinoma (SCC) of the hypopharynx that underwent surgery was performed. Ipsilateral paratracheal lymph node metastases occurred in 22% (14 out of 64) and the mean number of paratracheal lymph nodes dissected per side was 2.3 (range 1–6). Contralateral paratracheal lymph node metastases were present in 2% (1 out of 42). Sixty-seven percent with postcricoid SCC and 22% with pyriform sinus SCC developed clinical node-positive ipsilateral paratracheal lymph node metastases, whereas 11% with posterior pharyngeal wall SCC developed paratracheal metastases. There was a significant correlation between paratracheal lymph node metastasis and cervical metastasis (p = 0.005), and the primary tumor site (postcricoid, 57.1%; pyriform sinus, 20.0%; posterior pharyngeal wall, 8.3%) (p = 0.039). Patients with no evidence of paratracheal lymph node metastasis may have a survival benefit (5-year disease-specific survival rate, 60 vs. 29%). However, this result did not reach statistical significance (p = 0.071). The patients with SCC of the postcricoid and/or pyriform sinus were at risk for ipsilateral paratracheal lymph node metastasis; furthermore, patients with paratracheal node metastasis had a high frequency of cervical metastasis and a poorer prognosis. Therefore, routine ipsilateral paratracheal node dissection is recommended during the surgical treatment of patients with SCC of the postcricoid and/or pyriform sinus with clinical node metastases.

Pattern of lymph node metastasis in hypopharyngeal squamous cell carcinoma and indications for level VI lymph node dissection

“…Level VI node metastasis is a significant adverse prognostic factor. Joo et al found that patients with hypopharyngeal carcinoma and level VI node metastases have a high frequency of cervical metastasis at other levels and a poorer prognosis. Plaat et al reported that level VI node metastasis with extranodal spread is an important adverse prognostic factor for disease‐free and overall survival.…”

“…2 A 20% frequency of occult nodal metastases to ipsilateral level VI lymph nodes has been reported in patients with postcricoid lesions and classification N0 tumors that involve the pyriform fossa apex. 3,4 For laryngeal/hypopharyngeal and upper esophageal tumors, metastatic disease involving the level VI nodal group has been implicated in recurrent disease, particularly in patients with peristomal recurrence; this suggests the prognostic significance of positive level VI metastatic spread. 5 Treatment planning for patients with level VI metastasis must consider the likelihood of regional recurrence and/or dis-tant metastasis.…”

Pattern of cervical lymph node metastasis in medial wall pyriform sinus carcinoma

“…Only a few articles on the significance of PTLN in medial wall pyriform sinus carcinoma have been published, and most articles included laryngeal, hypopharyngeal, and esophageal cancear . Metastases to the thyroid gland and PTLN occur in up to 30% of patients with hypopharyngeal tumors . Metastatic disease involving this nodal group has been implicated in recurrent disease, suggesting a likely prognostic significance .…”

“…In our study, we performed level VI neck dissection based on preoperative inclusion criteria: positive preoperative image (n = 2), and potential risk of occult metastasis (T4a or pyriform sinus apex invasion, n = 37) . Level VI metastasis was confirmed by pathological analysis in six of the 39 (16.2%) subjects.…”

“…10,11 Metastases to the thyroid gland and PTLN occur in up to 30% of patients with hypopharyngeal tumors. 12 Metastatic disease involving this nodal group has been implicated in recurrent disease, suggesting a likely prognostic significance. 10 However, these lymph nodes are not usually included in conventional neck dissection and may develop independently from lymph node metastases at other levels.…”