University of Lyon 1, University of Lyon, F-69000, Lyon, France.
Faculty of Medicine Lyon-Est, F-69372, Lyon, France.
Rev Endocr Metab Disord. 2020 Jun;21(2):243-251. doi: 10.1007/s11154-020-09562-9.
Pituitary adenohypophyseal tumors are considered as benign and termed "adenomas". However, many tumors are invasive and a proportion of these exhibit an "aggressive behavior" with premature death due to progressive growth. Only very rare (0.2%) tumors with metastases are considered malignant and termed "carcinomas". Taking into account this variability in behavior and the oncological definition, pathologists have proposed changing the term adenoma to tumor. Here we explain why use the term tumor instead of adenoma and identify tumor characteristics, associated with a high risk for poor prognosis. In a cohort of 125 tumors with aggressive behavior (APT) and 40 carcinomas with metastases (PC), clinical and pathological features were very similar. The comparison of this cohort (APT+PC) with a reference surgical cohort of 374 unselected patients clearly shows that the two cohorts differ greatly, especially the percentage of tumors with Ki67 ≥ 10% (35%vs3%; p < 0.001). A five-tiered prognostic classification, associating invasion and proliferation, identified grade 2b tumors (invasive and proliferative), with a high risk of recurrence/progression. Because half of the APT+ PC tumors have a Ki67 index ≥10%, and 80% of them show 2 or 3 positive markers of proliferation, we suggest that tumors that are clinically aggressive, invasive and highly proliferative with a Ki67 ≥ 10%, represent tumors with malignant potential. The percentage of grade 2b tumors, suspected of malignancy, which will become aggressive tumors or carcinomas is unknown. It is probably very low, but higher than 0.2% in surgical series. Early identification and active treatment of these aggressive tumors is needed to decrease morbidity and prolong survival.
垂体腺垂体肿瘤被认为是良性的，被称为“腺瘤”。然而，许多肿瘤是侵袭性的，其中一部分表现出“侵袭性行为”，由于进行性生长而导致过早死亡。只有极少数（0.2%）有转移的肿瘤被认为是恶性的，被称为“癌”。考虑到这种行为的可变性和肿瘤学的定义，病理学家提出将腺瘤改为肿瘤。在这里，我们解释为什么使用肿瘤而不是腺瘤，并确定与预后不良风险高相关的肿瘤特征。在一组侵袭性行为（APT）的 125 个肿瘤和 40 个有转移的癌（PC）中，临床和病理特征非常相似。将这一组（APT+PC）与 374 例未选择的参考手术队列进行比较，清楚地表明两组之间存在很大差异，尤其是 Ki67≥10%的肿瘤比例（35%对 3%；p<0.001）。将侵袭性和增殖性与侵袭性和增殖性相关联的五层次预后分类，确定了 2b 级肿瘤（侵袭性和增殖性），复发/进展的风险高。由于 APT+PC 肿瘤中有一半的 Ki67 指数≥10%，并且其中 80%显示 2 或 3 个增殖的阳性标志物，因此我们建议具有侵袭性、增殖性和 Ki67≥10%的临床侵袭性肿瘤具有恶性潜能。恶性肿瘤的可能性的 2b 级肿瘤（疑似恶性肿瘤）的比例未知。它可能非常低，但高于手术系列中的 0.2%。需要早期识别和积极治疗这些侵袭性肿瘤，以降低发病率和延长生存期。
