Cervical Lymph Node Metastasis Regularity Of Piriform Sinus Hypopharyngeal Squamous Cell Carcinoma

Objective:To investigate cervical lymph node metastasis regularity of piriform sinus hypopharyngeal squamous cell carcinoma and to analyze the significance of cervical lymph node metastasis regularity in radiotherapy.Methods and materials:A retrospective analysis was made of 141 patients with piriform sinus hypopharyngeal cancer who were treated in our hospital(Radiotherapy department and Otolaryngological department)from January 2013 to October 2018.Summarize the basic situation of the primary tumor and cervical lymph node metastasis,the distribution of cervical lymph node metastasis and the situation of contralateral cervical lymph node metastasis.Statistical analysis was made on the factors that may affect the incidence of cervical lymph node metastasis and contralateral cervical lymph node metastasis.The difference of the incidence of cervical lymph node metastasis was compared byX~2 test,and the difference was statistically significant with P<0.05.Results:(1)Among 141 patients with piriform sinus hypopharyngeal squamous cell carcinoma,101 patients had cervical lymph node metastasis with 261 metastatic lymph nodes.The most common lymph node metastasis was in area?A,followed by area?and?B.Area?A,?A,?B and?B were rare and no metastasis was found in area?A,?B,?and?.The number of metastatic lymph nodes in area?and?accounted for 90.4%(236/261).There were 60patients with lymph node metastasis in other areas,with a total merger rate of 59.4%.(2)The incidence rate of total cervical lymph node metastasis was71.6%.Statistical analysis of various clinical factors showed that age,maximum diameter of the tumor and whether the tumor passed the midline of hypopharynx had statistical significance.(3)The incidence rate of contralateral cervical lymph node metastasis was 23.8%(24/101).The most common metastasis was in the contralateral area?A and?,accounting for 86.5%(32/37),followed by area?B and?A,and no contralateral metastasis was found in other areas.Statistical analysis of various clinical factors showed that the incidence rate of lymph node metastasis was 13.0%in 1-3metastatic lymph nodes group and 58.3%in?4 metastatic lymph nodes group(P<0.05).Conclusions:(1)Piriform sinus hypopharyngeal squamous cell carcinoma is prone to cervical lymph node metastasis,which mainly metastases to area?and?of cervical lymphatic drainage(90.4%)and often accompanies with lymph node metastasis in other areas.(2)The incidence rate of total cervical lymph node metastasis was71.6%,which was closely related to the maximum diameter of the tumor and whether the tumor passed the midline of hypopharynx.(3)The incidence rate of contralateral cervical lymph node metastasis was 23.8%,mainly to the contralateral area?A and?(86.5%).The incidence of contralateral lymph node metastasis is related to the number of metastatic lymph nodes.When the number of metastatic lymph nodes is more than 4,the situation of contralateral lymph node metastasis should be paid great attention to avoid omission.(4)Cervical lymph node metastasis regularity of piriform sinus hypopharyngeal squamous cell carcinoma has important reference value for delineating the target area in radiotherapy.