Clinical Characteristics And CT Imaging Features Of Peripheral Lung Squamous Cell Carcinoma With A Diameter Of ≤2 Cm

Objective To explore the clinical characteristics and CT imaging manifestations of peripheral pulmonary nodules with a diameter of ≤2cm in squamous cell carcinoma,providing guidance for its early diagnosis and treatment.Methods Retrospective analysis was made on the patients who received surgical treatment in thoracic surgery Department of Shandong Provincial Hospital from January 2020 to December 2022.The patients whose preoperative CT examination showed that the pulmonary nodules were located in 1/3 of the lung field and the longest diameter was ≤2cm(lung window measurement).According to postoperative pathology,there were 34 patients with squamous cell carcinoma(pLSC group),391 patients with adenocarcinoma(pLAC group),and 87 patients with benign nodules(pBLN group),totaling 512 patients.Record the imaging manifestations of pulmonary nodules on CT,including their size,nature(solid/sub solid),shape(quasi circular/irregular),boundary(clear/blurry),lobulation sign(+/-),spicule sign(+/-),bronchial truncation sign(+/-),vascular bundle sign(+/-),pleural traction sign(+/-),vacuolar sign(+/-),hilar/mediastinal lymph node enlargement(+/-),etc.Compare the pLSC group with the pLAC group and pBLN group,and verify whether the results have statistical significance through statistical methods such as chi square test.And record the clinical characteristics of patients in the pLSC group,including general information such as age,gender,smoking history(+/-),follow-up status,pathological characteristics including differentiation degree,lymph node metastasis,pathological staging,etc.Results 1.Clinical characteristics:Among the 34 patients with pLSC,31(91.2%)were male,with an average age of 64.9 ± 11.54 years.29(85.3%)had a history of smoking.Among the 18 patients who underwent follow-up observation,14(77.8%)showed significant growth of nodules compared to before,with a doubling time of 92～357 days;Postoperative pathology showed that 31 cases(91.2%)had low to moderate differentiation,only 1 case(2.9%)had lymph node metastasis(stage ⅡB),and the remaining 33 cases(97.1%)were all early(stageⅠA).2.Imaging manifestations:pLSC often presents as solid(100%)nodules with regular morphology(91.2%)and clear boundaries(64.7%).The incidence of lobulation sign(70.1%),hilar/mediastinal lymph node enlargement(55.9%).and bronchial truncation sign(23.5%)is higher than that of pLAC and pBLN,while the incidence of hair prick sign(32.4%)is lower than that of pLAC.The above results have statistical significance(P<0.05).Conclusion 1.pLSC is more common in elderly men with a long-term history of heavy smoking,and has the same high-risk factors as traditional central lung squamous cell carcinoma.2.Peripheral pulmonary nodules appear on CT as solid nodules with regular morphology and clear boundaries,accompanied by lobulation sign and hilar/mediastinal lymph node enlargement.Based on clinical characteristics,the possibility of pLSC should be vigilant and closely followed up for observation.3.The degree of differentiation of pLSC is low and its growth rate is fast.If there is a high suspicion of pLSC,early surgical treatment should be performed.