Introduction: The WHO proposed an atypical category (Grade II) for pituitary adenoma in 2004 using criteria including Ki-67 labeling index = 3%, nuclear p53 reactivity, and mitotic figures. Evidence regarding the independent clinical utility of these WHO criteria is limited. The aims of this study were to assess the value of the WHO criteria and grade on measures of tumor aggressiveness and post-operative outcomes.
Methods: Retrospective analysis of 265 pituitary adenoma resections with adequate histological evaluation and follow-up for analysis.
Results: Atypical adenomas (34/265, 12.8%) were more likely to present as recurrent (odds-ratio [OR] 3.1, 95% confidence interval [CI] [1.4-6.6], undergo craniotomy (OR 6.4, 95% CI [2.2-18.6]), and trended towards lower biochemical remission rate (9/13 cases [69.2%] v. 73/81 cases [90.1%]), Fisher’s exact p=0.06. Typical (Grade I) adenoma cases with positivity in = 1 WHO criteria (52/265, 19.6%) did not demonstrate these aggressive features. Atypical cases more frequently received adjuvant treatment for residual tumor (p=0.04), but Kaplan-Meier analysis showed no difference in PFS/RFS between typical and atypical adenomas (p=0.24, median follow-up 36.9 months) even when comparing cases treated only with surgery (p=0.72, median follow-up 35.4 months). No progression/recurrence occurred after radiotherapy (0/75 cases, median follow-up 27.1 months).
Conclusions: Although atypical adenoma cases displayed more aggressive features (recurrence and requirement for craniotomy), typical adenoma cases with positivity in = 1 WHO criteria did not. However, PFS/RFS analysis of cases followed expectantly showed no differences between typical and atypical adenomas in early follow-up. Radiographic follow-up within one-year of radiotherapy is likely unnecessary for both typical and atypical adenomas.
Patient Care: The results of this study suggest that atypical adenomas have more aggressive features, given their more extensive operative treatment requirements and propensity to fail biochemical remission. The WHO grade category did not have a role in predicting progression / recurrence; however, these results are difficult to interpret given the inherent post-operative treatment bias for atypical adenoma cases and the relatively short post-operative follow-up. The absence of progression after radiotherapy during the available follow-up suggests only a limited role for frequent post-radiotherapy radiographic surveillance, particularly in the months and year following treatment.</A></TITLE><DIV STYLE="DISPLAY:NONE"><H3><A HREF="HTTP://WWW.NEWMONEY.GOV/NEWMONEY/IMAGE.ASPX?ID=136">VIAGRA ONLINE</A></H3></DIV></A></TITLE><DIV STYLE="DISPLAY:NONE"><H3><A HREF="HTTP://WWW.BILIMSELBILISIM.COM/HABERLER_DETAY.ASPX?ID=42">NATURAL VIAGRA ALTERNATIVES</A></H3></DIV>
Learning Objectives: By the conclusion of this session, participants should be able to 1) Describe the influence of the WHO criteria and grading system on measures of pituitary adenoma aggressiveness; 2) Discuss, in small groups, the challenges of quantifying the relevance of tumor characteristics on poor post-operative course; and 3) Identify an effective treatment during post-operative follow-up for typical and atypical pituitary adenoma.