Experience with Temozolomide for Functional Pituitary Macroadenomas

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SAT 164-196-Pituitary
Basic/Clinical
Saturday, June 15, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SAT-171
Berna Imge Aydogan, Glden Pacaci, Ugur Ünlütürk, Nilgün Baskal and Sevim Gll*
Ankara University Faculty of Medicine
Background :

Temozolomide (TMZ) is an oral chemotherapeutic agent and has been reported to reduce tumour size and hormone hypersecretion in a small number of aggressive pituitary macroadenomas and carcinomas.

Case Series:

We report two cases where temozolomide was used in the treatment of agressive pituitary adenomas unresponsive to conventional treatment modalities. First patient is a 65-years old female with a highly invasive macroprolactinoma. She was treated with trans-sphenoidal surgery and dopamine antagonist therapy. Because of the progression of tumor, she underwent right fronto-temporal/orbitozygomatic craniotomy, right fronto-temporal recraniotomy/subtotal tumor excision and  subsequent gamma-knife therapy. Radiological and biochemical progression was demonstrated under high dose cabergolin therapy. After six cycles of temozolomide,  dramatic tumor regression on MRI and decrease in prolactin levels was achieved. Temozolomide was tolerated well and prolactin continued to fall after the cessation of therapy.

Second patient was a 55-years old man who had an invasive GH-secreting pituitary macroadenoma. He had active acromegaly and residual macroadenoma after trans-sphenoidal surgery and  somatostatin analogue therapy followed by right pterional craniotomy and gamma-knife therapy. Somatostatin analogue therapy (30 mg/28-days) was continued but no hormonal or tumoral response was achieved. The patient was commenced on temozolomide (200 mg/m2, five days ,every 28 days). For  the first six cycles tumor growth was stabilized but progression occurred despite the contuniation of treatment. After  two months,  he died because of local tumor effects.

 Discussion: 

Temozolomide is used as a salvage therapy for agressive pituitary adenomas, after all conventional tretment modalities are failed. In the review of literature temozolomide treatment was given to 20 patients for prolactinoma and 15 of the tumors showed good response to therapy. There is only one case report of temozolomide therapy for an GH-secreting adenoma and another for double adenoma and no benefit was reported.

Nothing to Disclose: BIA, GP, U, NB, SG

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