Department of Medical Imaging, Ganzhou People's Hospital, The Affiliated Ganzhou Hospital of Nanchang University, 16th Meiguan Avenue, Ganzhou, 341000, P.R. China.
Department of Medical Hematology, Ganzhou People's Hospital, The Affiliated Ganzhou Hospital of Nanchang University, Ganzhou, China.
BMC Med Imaging. 2023 Aug 14;23(1):105. doi: 10.1186/s12880-023-01065-8.
Pulmonary sarcomatoid carcinoma (PSC) is a rare subtype of non-small cell lung cancer (NSCLC) but differs in terms of treatment strategies compared with conventional-NSCLC (c-NSCLC). However, preoperative CT differentiation between PSC and c-NSCLC remains a challenge. This study aimed to explore the CT findings and prognosis of PSC compared with c-NSCLC of similar tumor size.
Clinical data and CT findings of 31 patients with PSC and 87 patients with c-NSCLC were retrospectively analyzed. Clinical data included sex, age, and smoking history. CT findings included tumor size, tumor location, calcification, vacuole/cavity, pleural invasion, mean CT value, and low-attenuation area (LAA) ratio. Kaplan‒Meier curves and log-rank tests were used for survival analysis. A Cox regression model was constructed to evaluate prognostic risk factors associated with overall survival (OS). The Spearman correlation among clinicoradiological outcomes were analyzed.
The mean tumor size of PSC and c-NSCLC were both 5.1 cm. The median survival times of PSC and c-NSCLC were 8 months and 34 months, respectively (P < 0.001). Calcification and vacuoles/cavities were rarely present in PSC. Pleural invasion occurred in both PSC and c-NSCLC (P = 0.285). The mean CT values of PSC and c-NSCLC on plain scan (PS), arterial phase (AP), and venous phase (VP) were 30.48 ± 1.59 vs. 36.25 ± 0.64 Hu (P = 0.002), 43.26 ± 2.96 vs. 58.71 ± 1.65 Hu (P < 0.001) and 50.26 ± 3.28 vs. 64.24 ± 1.86 Hu (P < 0.001), the AUCs were 0.685, 0.757 and 0.710, respectively. Compared to c-NSCLC, PSC had a larger LAA ratio, and the AUC was 0.802, with an optimal cutoff value of 20.6%, and the sensitivity and specificity were 0.645 and 0.862, respectively. Combined with the mean CT value and LAA ratio, AP + VP + LAA yielded the largest AUC of 0.826. The LAA ratio were not independent risk factors for PSC in this study. LAA ratio was negatively correlated with PS (r = -0.29), AP (r = -0.58), and VP (r = -0.66). LAA showed a weak positive correlation with tumor size(r = 0.27).
PSC has a poorer prognosis than c-NSCLC of similar tumor size. The mean CT value and LAA ratio contributes to preoperative CT differentiation of PSC and c-NSCLC.
肺肉瘤样癌（PSC）是一种罕见的非小细胞肺癌（NSCLC）亚型，但与传统 NSCLC（c-NSCLC）相比，其治疗策略有所不同。然而，术前 CT 区分 PSC 和 c-NSCLC 仍然具有挑战性。本研究旨在探讨 PSC 的 CT 表现和预后，并与大小相似的 c-NSCLC 进行比较。
回顾性分析了 31 例 PSC 患者和 87 例 c-NSCLC 患者的临床资料和 CT 表现。临床资料包括性别、年龄和吸烟史。CT 表现包括肿瘤大小、肿瘤位置、钙化、空泡/空腔、胸膜侵犯、平扫 CT 值、动脉期 CT 值、静脉期 CT 值和低衰减区（LAA）比例。采用 Kaplan-Meier 曲线和对数秩检验进行生存分析。构建 Cox 回归模型评估与总生存期（OS）相关的预后危险因素。分析临床影像学结果之间的 Spearman 相关性。
PSC 和 c-NSCLC 的平均肿瘤大小均为 5.1cm。PSC 和 c-NSCLC 的中位生存时间分别为 8 个月和 34 个月（P<0.001）。PSC 中很少出现钙化和空泡/空腔。PSC 和 c-NSCLC 均有胸膜侵犯（P=0.285）。PSC 和 c-NSCLC 在平扫（PS）、动脉期（AP）和静脉期（VP）的平均 CT 值分别为 30.48±1.59Hu 与 36.25±0.64Hu（P=0.002）、43.26±2.96Hu 与 58.71±1.65Hu（P<0.001）和 50.26±3.28Hu 与 64.24±1.86Hu（P<0.001），其 AUC 分别为 0.685、0.757 和 0.710。与 c-NSCLC 相比，PSC 的 LAA 比例更大，AUC 为 0.802，最佳截断值为 20.6%，灵敏度和特异性分别为 0.645 和 0.862。结合平均 CT 值和 LAA 比例，AP+VP+LAA 获得了最大的 AUC 为 0.826。LAA 比例不是本研究中 PSC 的独立危险因素。LAA 比例与 PS（r=-0.29）、AP（r=-0.58）和 VP（r=-0.66）呈负相关。LAA 与肿瘤大小呈弱正相关（r=0.27）。
PSC 的预后比大小相似的 c-NSCLC 差。平均 CT 值和 LAA 比例有助于术前 CT 区分 PSC 和 c-NSCLC。
