Pituitary metastasis from a renal cell carcinoma progressed after sorafenib treatment
A 51-year-old man originally presented with an asymptomatic tumor in his left kidney revealed by a routine abdomen ultrasonography in October 2005. His medical history was unremarkable except for 11 years of hypertension, which was controlled well with calcium antagonist. Radical nephrectomy was then undertaken and pathologic examination showed clear-cell RCC (), staged T3N0M0. He underwent cytokine therapy with interleukin-2 for 3 months after surgery and felt well. However, in subsequent routine examinations, a computed tomographic (CT) scan suggested metastases to bilateral adrenal glands (), retroperitoneal lymph nodes, and multiple bones. Brain magnetic resonance imaging (MRI) was then performed and showed diffuse enlargement of the pituitary gland (), which was considered pituitary nonfunctional adenoma or pituitary hyperplasia. In June 2006, the patient began treatment with sorafenib, taking 400 mg orally twice daily. Treatment was interrupted in the third week and then between the 12th and 16th week because of grade 3 hand-foot reaction syndrome and aggravated hypertension accompanied by grade 2 alopecia and arthralgia according to Common Terminology Criteria for Adverse Events (CTCAE) v3.0. After the interruption, the dose of sorafenib was reduced to 400 mg orally once daily. After 8 weeks of sorafenib treatment, CT scan of the abdomen showed tumor shrinkage and partial response (), which was evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST). This partial response status was verified 4 weeks later. In the 20th week, the patient felt rapid deterioration with blurry vision. Physical examination revealed left-sided temporal hemianopia, ptosis of the left upper lid, left sixth nerve palsy, and diplopia. Hormonal evaluation suggested adrenocorticotropic hormone (ACTH) deficiency and hyperprolactinemia (). Additional brain CT scan showed a Sellar mass with suprasellar extension compressing the optic chiasm and eroding the Sellar base (). In November 2006, transsphenoidal surgery revealed a vascular tumor that invaded the Sellar base and the normal pituitary gland. Only biopsy was performed, and pathologic examination showed clear-cell carcinoma consistent with pituitary metastasis of RCC (). Treatment with sorafenib was stopped when disease progression was detected. The patient underwent conformal radiotherapy to the pituitary tumor bed at a dose of 3,000 cGy in 10 fractions and then 600 cGy in 3 fractions. After radiotherapy, his visual acuity and visual field recovered partially. One month later, multiple bilateral lung nodules were suggested by chest CT scan. In September 2007, the patient died due to dyspnea. Survival time was 23 months from nephrectomy, 16 months from initial diagnosis of metastases and use of sorafenib, and 9 months from diagnosis of symptomatic pituitary metastasis.