Prall Friedrich, Schmitt Oliver, Schiffmann Leif
Institute of Pathology, Rostock University, Strempelstraße 14, D-18055, Rostock, Germany.
Institute of Anatomy, Rostock University, Gertrudenstraße 11, D-18055, Rostock, Germany.
World J Surg Oncol. 2015 Apr 21;13:155. doi: 10.1186/s12957-015-0572-z.
High interobserver variation is a well known drawback of conventional tumor regression grading, and reaching consensus among pathologists may require a considerable effort. Therefore, in this study, morphometry was tried to assess tumor regression, and its prognostic role was explored.
Tumor regression was quantified by a point counting method to yield tumor area fraction (TAF) as an index of remaining vital tumor.
In a series of 104 patients with clinically advanced rectal cancer treated with neoadjuvant radiochemotherapy, TAFs were distributed continuously towards complete regression which was observed in 8.7% of the cases. Plotting TAFs grouped by a conventional regression grading (Dworak's) revealed considerable overlap between groups. In a control series of untreated cancers, only TAFs of cancers with an expansive invasive border were setoff clearly from TAFs obtained for the study cases, but TAFs of control cases with an infiltrative invasive border and mucinous carcinomas extended well into the range of TAFs recorded for regressing tumors. Locoregional recurrence (N = 10) was significantly associated with perineural tumor infiltration and capsule transgressing lymph node metastasis/tumor deposits but not with the degree of tumor regression. Overall survival was better for patients with major regressions (≤20th percentile by morphometry, or Dworak regression grade (DRG) 4/5), although statistical significance was not reached.
Morphometry of tumor regression is feasible and explains why conventional regression grading is so difficult to perform. Assessment of tumor regression, by subjective grading or morphometry, does not appear to convey major prognostic information, at least not substantially beyond histopathological tumor staging. This observation discourages expending too much effort on developing this aspect of the pathomorphological workup of the resection specimens.
观察者间差异大是传统肿瘤消退分级法众所周知的缺点，病理学家之间达成共识可能需要付出相当大的努力。因此，在本研究中，尝试采用形态测量法评估肿瘤消退情况，并探讨其预后作用。
采用点计数法对肿瘤消退进行量化，得出肿瘤面积分数（TAF）作为残留存活肿瘤的指标。
在一组104例接受新辅助放化疗的临床晚期直肠癌患者中，TAF呈连续分布，直至完全消退，8.7%的病例出现完全消退。按传统消退分级（德沃拉克分级）分组绘制TAF，结果显示各组之间存在相当大的重叠。在一组未经治疗的癌症对照系列中，只有具有膨胀性浸润边界的癌症的TAF明显不同于研究病例的TAF，但具有浸润性浸润边界的对照病例和黏液腺癌的TAF很好地延伸到消退肿瘤记录的TAF范围内。局部复发（N = 10）与神经周围肿瘤浸润和突破包膜的淋巴结转移/肿瘤沉积物显著相关，但与肿瘤消退程度无关。主要消退（形态测量法处于第20百分位数以下，或德沃拉克消退分级（DRG）为4/5）的患者总生存期较好，尽管未达到统计学显著性。
肿瘤消退的形态测量法是可行的，这也解释了为什么传统消退分级如此难以实施。通过主观分级或形态测量法评估肿瘤消退，似乎并不能传达主要的预后信息，至少在很大程度上不超过组织病理学肿瘤分期。这一观察结果不鼓励在切除标本的病理形态学检查的这一方面投入过多精力。
