Tumor spread through air space, the clinical implications for T factor and effects on the disease recurrence and prognosis

Lymphatic permeation and vascular invasion should not be integrated as lymphovascular invasion in lung adenocarcinoma

OBJECTIVE

Lymphatic permeation (LY) and vascular invasion (VI) are well-known as postoperative prognostic factors in non-small cell lung cancer (NSCLC). Some reports use the term "lymphovascular invasion (LVI)" in reference to the integration of LY and VI. The purpose in this study is to elucidate whether NSCLC with LY or VI can be labeled as LVI-positive NSCLC or it should be treated as an LY- or VI-positive tumor, respectively.

METHODS

We reviewed 601 completely resected lung adenocarcinomas and squamous cell carcinomas, and examined the respective prognostic and biological significance of LY and VI.

RESULTS

Among 454 adenocarcinomas, multivariate survival analyses showed that LY and VI were unfavorable prognostic factors in stages II and III and stages I and II, respectively. Conversely, this relationship was not found among 147 squamous cell carcinomas. Patients with adenocarcinomas with LY and VI had a significantly worse prognosis than those with adenocarcinomas with LY or VI in stage II, but not in stage I. Among 149 recurrent adenocarcinomas, only VI had a strong effect on early recurrence and shorter post-recurrence survival. LY and VI were predictors for multiple organ recurrence of adenocarcinoma. The recurrence of adenocarcinoma with LY was high in the ipsilateral mediastinal lymph nodes, whereas VI was significantly correlated with distant metastasis to organs, such as the brain, liver, and adrenal gland.

CONCLUSIONS

LY and VI have differing effects postoperative prognosis and recurrence-relevant events, suggesting that these pathological findings should not be integrated as LVI.

[Progress on the Study of Tumor Spread Through Air Spaces in the Clinicopathological Characteristics of Lung Adenocarcinoma and Its Influence on the Surgical Treatment and Prognosis of Lung Cancer]

肿瘤肺泡腔内播散（tumor spread through air spaces, STAS）作为一种新的病理侵袭方式，与诸多临床病理因素紧密相关。在肺腺癌中，微乳头和实体型病理亚型与之关系最为密切；针对早期肺腺癌存在STAS，手术类型的治疗上肺叶切除似乎优于亚肺叶切除而获益，可能上调早期肺癌的病理分期；同时，STAS与鳞癌等非小细胞肺癌（non-small cell lung cancer, NSCLC）关系密切。此外，STAS的术中冰冻切片病理检测困难，亦有争议存在。STAS作为肿瘤复发的独立危险因素，亦是提示预后不良的重要因素，本文将STAS的研究现状和进展作一综述。