BACKGROUND: Pituitary adenomas are usually well-differentiated tumors but may show locally aggressive behavior. AIM: To investigate the relationship between proliferation and apoptosis parameters and tumor recurrence in a series of 20 radically resected pituitary macroadenomas (11 functioning, 9 non-functioning). MATERIALS AND METHODS: Proliferative activity and DNA ploidy were analyzed by flow cytometry (FCM) on fresh surgical specimens. Immunohistochemistry for Ki-67/MIB-1 and for the anti-apoptotic protein Bcl-2 was performed on paraffin-embedded specimens from the same tumors. Tumor regrowth was evaluated by magnetic resonance imaging (MRI). RESULTS: Six adenomas recurred after surgery, regardless of hormonal hypersecretion. Pre-surgical tumor size was significantly higher in recurrent than in non-recurrent adenomas (p=0.003). Pre-surgical MRI demonstrated cavernous sinus (CS) invasiveness in all recurrent tumors, while none of the non-invasive adenomas recurred (p=0.042, by Fisher's exact test). The DNA content was aneuploid in 5/20 adenomas, one of which recurred. Cell percentages in the S (%SPF) and G2+M (%G2-M) phases and proliferative index (PI) (PI=%SPF+%G2-M) were significantly higher in aneuploid than in diploid adenomas (p<0.05), but no significant differences concerning all FCM parameters were observed between recurrent and non-recurrent adenomas. Similarly, MIB-1 did not show a significant difference of expression between recurrent and non-recurrent adenomas (p=0.33). Bcl-2 immunoreactivity was detected in 12/15 pituitary adenomas, involving 63±35% of tumor cells, regardless of tumor recurrence. CONCLUSIONS: In this group of radically resected pituitary macroadenomas, neuroradiological finding of CS invasiveness--but not FCM parameters nor MIB-1 and Bcl-2 expression--is useful for predicting tumor recurrence.
BACKGROUND: Pituitary adenomas are usually well-differentiated tumors but may show locally aggressive behavior. AIM: To investigate the relationship between proliferation and apoptosis parameters and tumor recurrence in a series of 20 radically resected pituitary macroadenomas (11 functioning, 9 non-functioning). MATERIALS AND METHODS: Proliferative activity and DNA ploidy were analyzed by flow cytometry (FCM) on fresh surgical specimens. Immunohistochemistry for Ki-67/MIB-1 and for the anti-apoptotic protein Bcl-2 was performed on paraffin-embedded specimens from the same tumors. Tumor regrowth was evaluated by magnetic resonance imaging (MRI). RESULTS: Six adenomas recurred after surgery, regardless of hormonal hypersecretion. Pre-surgical tumor size was significantly higher in recurrent than in non-recurrent adenomas (p=0.003). Pre-surgical MRI demonstrated cavernous sinus (CS) invasiveness in all recurrent tumors, while none of the non-invasive adenomas recurred (p=0.042, by Fisher's exact test). The DNA content was aneuploid in 5/20 adenomas, one of which recurred. Cell percentages in the S (%SPF) and G2+M (%G2-M) phases and proliferative index (PI) (PI=%SPF+%G2-M) were significantly higher in aneuploid than in diploid adenomas (p<0.05), but no significant differences concerning all FCM parameters were observed between recurrent and non-recurrent adenomas. Similarly, MIB-1 did not show a significant difference of expression between recurrent and non-recurrent adenomas (p=0.33). Bcl-2 immunoreactivity was detected in 12/15 pituitary adenomas, involving 63±35% of tumor cells, regardless of tumor recurrence. CONCLUSIONS: In this group of radically resected pituitary macroadenomas, neuroradiological finding of CS invasiveness--but not FCM parameters nor MIB-1 and Bcl-2 expression--is useful for predicting tumor recurrence.
Authors: G Fontanini; S Vignati; D Bigini; A Mussi; M Lucchi; C A Angeletti; F Basolo; G Bevilacqua Journal: Br J Cancer Date: 1995-05 Impact factor: 7.640
Authors: Heather M Kistka; Rebecca A Kasl; Arash Nayeri; Andrea L Utz; Kyle D Weaver; Lola B Chambless Journal: J Neurol Surg B Skull Base Date: 2015-05-08