Application value of ultrasound-guided fine-needle aspiration cytology of lymph nodes in the pre-radiotherapy evaluation of thoracic malignant cancer

Objective To investigate the application value of ultrasound-guided fine-needle aspiration cytology of lymph nodes in the pre-radiotherapy evaluation of superficial lymph nodes metastases in patients with lung cancer and esophageal cancer. Methods A total of 115 patients with lung cancer and esophageal cancer prepared for thoracic radiotherapy from February 2017 to September 2018 in Cancer Hospital of Huanxing Chaoyang District Beijing were retrospectively analyzed. Ultrasound-guided fine-needle aspiration cytology examination was performed in 166 lymph nodes. Puncture tissues were prepared for cytology production. Then cytological specialist read the film to evaluate if the cancer cells metastasis were present after conventional papanicolaou staining. The effects of short diameter of lymph nodes, blood flow signal and tumor characteristics of patients on the results of cytological examination were analyzed. Results The ultrasound results showed the median short diameter of lymph nodes was 0.6 cm (0.2-3.5 cm), and 25 (15.1%) lymph nodes had blood flow signals, 50 (30.1%) lymph nodes had positive results of puncture tissues cytology. The positive rate of puncture tissues cytology was 10.0% (4/40), 21.6% (21/97) and 86.2% (25/29) in the short diameter of lymph nodes 0.05). Pathological types had a significant influence on cytological results (χ 2=8.050, P=0.045). Lymph node metastasis of the upper mediastinum was a risk factor for lymph node metastasis in lower neck and supraclavicular region (χ 2=9.699, P=0.002). Location of primary tumor, T stage and chemotherapy history had no significant influence on cytological results in patients with esophageal cancer (all P > 0.05). Conclusions Ultrasound-guided fine-needle aspiration cytology is safe and efficient. It can be used to evaluate the metastasis status of superficial lymph nodes in pre-radiotherapy patients with lung cancer and esophageal cancer. Key words: Radiotherapy; Lymphatic metastasis; Ultrasound-guided puncture; Cytology