Prognostic indicators in pituitary tumors.

Recent advances in molecular pathology have shed light not only on the cellular composition and derivation of various tumors, but also on their growth potential, likelihood of recurrence, and prognosis. The development of reliable and prognostically informative methods of assessing tumor behavior is particularly important in pituitary tumors, where no precise correlation exists between morphology and clinical aggressiveness. Among the numerous morphologic techniques that have been introduced in the last three decades, some have gained popularity due to their reliability and ease of performance, whereas others have fallen from favor due to their inconsistency and insensitivity in distinguishing indolent from aggressive pituitary tumors. Yet others, due to cost and complexity, never came into general use. We predict that the immunohistochemical methods now in use for assessment of tumor behavior will be complemented and partly replaced by molecular genetic procedures in the future.