Dopamine Agonists Withdrawal Study of Invasive Prolactinomas Involving the Cavernous Sinus

For giant or large invasive prolactinomas involving the cavernous sinus, whether the drug can be safely withdrawn after the tumor volume and prolactin(PRL) level have been effectively controlled through pharmacological treatment still remains unknown.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.

Primary outcomes

• Change from baseline on PRL level [Up to 2 years]: Record the result of PRL on every 3 month follow-up visit

Secondary outcomes

• Change from baseline on tumor volume measured by enhanced pituitary Magnetic Resonance Imaging（MRI） [Up to 2 years]: Record the tumor volume from enhanced pituitary MRI on every 3 month follow-up visits
• Change from baseline of visual acuity [Up to 2 years]: Record the Visual acuity on every 3 month follow-up visit
• Change from baseline on 5 point visual field scale [Up to 2 years]: Record the Visual field scale on every 3 month follow-up visit, 0 = normal, no vision loss; 1 = one quadrant vision loss; 2 = two quadrants of vision loss; 3 = three quadrants of vision loss; 4 = four quadrants of vision loss but retain a central tubular vision; 5 = blind

Sex: All, ages: 15 Years to 70 Years

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.

• Wu ZB, Yu CJ, Su ZP, Zhuge QC, Wu JS, Zheng WM. Bromocriptine treatment of invasive giant prolactinomas involving the cavernous sinus: results of a long-term follow up. J Neurosurg. 2006 Jan;104(1):54-61. doi: 10.3171/jns.2006.104.1.54. PMID 16509147
• Wu ZB, Su ZP, Wu JS, Zheng WM, Zhuge QC, Zhong M. Five years follow-up of invasive prolactinomas with special reference to the control of cavernous sinus invasion. Pituitary. 2008;11(1):63-70. doi: 10.1007/s11102-007-0072-4. PMID 17917811

• Zhebao Wu, Medical PhD, Study chair, Ruijin Hospital