The purpose of this study is to observe whether dopamine agonists can be safely withdrawn after the tumor volume and prolactin level of invasive prolactinomas involving the cavernous sinus have been effectively controlled through pharmacological treatment.

For giant or large invasive prolactinomas involving the cavernous sinus, whether the drug can be safely withdrawn after the tumor volume and prolactin(PRL) level have been effectively controlled through pharmacological treatment still remains unknown. The study objects are patients with invasive prolactinomas involving the cavernous sinus, which were invaded the cavernous sinus to an extent corresponding to Grade III or IV, according to the classification scheme of Knosp and colleagues, who had undergone pharmacological treatment including bromocriptine or cabergoline. Observation will be started after drug withdrawal criteria are reached (PRL remains normal level for no less than two years; tumor volume has shrank more than 50%, and the distance is more than 5mm between tumor and optical nerve),the patients are randomized to withdrawal group or continue treatment group.Observational items include changes of PRL level, tumor volume as well as vision acuity and visual fields. If elevated PRL or tumor relapse is observed, pharmacological treatment will be restarted.

Inclusion Criteria:

1. Aged between 15 and 70 years old, either sex;
2. Karnofsky performance status ≥ 70;
3. Patients who were suffered Invasive prolactinomas involving the cavernous sinus , referring to ①Serum prolactin level>200ng/ml, or >4000mIU/L;②enhanced Magnetic Resonance images confirm tumor invasion into cavernous sinus, i.e. Knosp grade Ⅲ or Ⅳ, and were treated by dopamine agonists treatment;
4. PRL remains normal level for no less than two years;
5. Tumor volume has shrank more than 50%, and the distance is more than 5mm between tumor and optical nerve;
6. The patient has signed the informed consent.

Exclusion Criteria:

1. Patients concomitantly taking the psychotropic drugs or other drugs causing elevated PRL ;
2. Patients with parkinson disease and is taking dopaminergic agents;
3. Patients with prolactinoma who received Gamma knife treatment;
4. Patients who use any dopamine receptor agonists other than bromocriptine and cabergoline;
5. Patients taking the other prolactinomas simultaneously;
6. pregnant or lactating women, or women preparing pregnant;
7. Patients with poor compliance, who cannot implement the program strictly.

invasive prolactinomas involving the cavernous sinus

The individual patient Data would not be shared to the third facility, but the sponsor hasn't decided whether to share the individual patient date to the other related studies hold by himself in the future.