非小细胞肺癌影像学与病理学靶区关系的研究

A comparative study on radiology and pathology target volume in non-small-cell lung cancer

目的 通过对非小细胞肺癌 (NSCLC)患者影像学肉眼肿瘤区 (grosstumorvolume ,GTV)与病理学GTV之间的关系的研究 ,明确NSCLC患者影像学GTV与病理学GTV之间的关系 ,明确NSCLC不同病理类型之间电镜下侵袭关系 ,以精确确定CTV边缘。方法 2 0 0 1年 2月～ 2 0 0 2年 2月间 43例接受手术治疗的NSCLC患者 ,术前行CT检查 ,确定肿瘤在冠状轴 (X轴 )、矢状轴 (Y轴 )、人体长轴 (Z轴 )三维径线上的大小 ;术后病理检查 ,确定肿瘤在X、Y、Z轴径线上的大小及各径线上的侵袭距离。结果 在不考虑电镜下侵袭的情况下 ,影像学的GTV与病理学的GTV在三维方向上是基本吻合的 ;腺癌平均侵袭范围为 2 .18mm ,鳞癌为 1.3 3mm (P =0 .0 0 1)。腺癌的侵袭范围 95%在 7mm之内 ,鳞癌为 5mm。结论 影像学的GTV与病理学的GTV是基本吻合的 ,在三维适形放疗和调强放疗靶区定位时 ,可以用影像学的GTV代替病理学的GTV。从GTV到临床靶区的扩充区 ,腺癌需要 7mm包括 95%的侵袭范围 ,而鳞癌仅需 5mm。

Objective Defining the margin of clinical target volume (CTV) is very important for three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radia tion therapy(IMRT). In this study, according to the comparison between gross fo mor volume(GTV) silhouretted by radiology and pathology in non-small-cell lung cancer (NSCLC), we tried to define the c orrelation of GTV by radiology and pathology, and assess the degree of correlati on to local microscopic extension(ME) among different pathologic types of NSCLC, so as to define the margin of CTV precisely. Methods From February 2001 to February 2002, forty-three NSCLC patients affer surgical resection were studied. All patients had had CT scans of the ches t before surgery and routine pathology examination after surgery. The tumor si ze at X(lateral direction)?Y(ventrodorsal direction) and Z(craniocau dal direction) axes were measured on CT. Also by pathology examination, the tumor size at X?Y?Z axes and the degree of ME at X?Y?Z a xes were measured, respectively. Results Without taking into account the value of ME, there was almost total agreement on the GTV by radiology and pathology in three dimensions. The mean val ue of ME was 2.18 mm for adenocarcinoma (ADC) and 1.33 mm for squamous ce ll car cinoma (SCC)(P=0.001). But, taking into account 95% of the ME, a margi n of 7 mm and 5 mm must be allowed for ADC and SCC, respectively. Conclusion There exists a correlation of GTV by radiology and pathology. In the target vol ume defining for 3DCRT and IMRT, we could use th e GTV by radiology instead of the GTV by pathology, with the ME being different for ADC and SCC. To cover 95% of the ME, the margin from GTV to CTV must be exte nded to 7 mm and 5 mm for ADC and SCC, respectively.