Merkezi Sinir Sistemi Tümörleri/Hipofiz Adenomu

Pituitary Adenoma

Overview

• Comprise ~10% of intracranial tumors
• Benign histologically
• Can cause significant morbidity due to 1) hormonal imbalances and 2) local compression of critical structures (optic chiasm and hypothalamus)
• Treatment overview:
  • Microadenoma, not secreting prolactin: surgery
  • Microadenoma, secreting prolactin: bromocriptine
  • Macroadenoma: multimodality approach, typically surgery, adjuvant RT and if secretory hormone suppression

Proton Therapy

• Loma Linda; 2006 (1991-2001) PMID 16257131 -- "Fractionated proton beam irradiation of pituitary adenomas." (Ronson BB, Int J Radiat Oncol Biol Phys. 2006 Feb 1;64(2):425-34. Epub 2005 Oct 27.)
  • Retrospective. 47 patients with pituitary adenomas. 42 prior rebaşlık, 5 primary RT. Functional 49% (n=23). Median dose 54 CGE in 30 fractions, mean target volume 8 cm3
  • Outcome: Stabilization in 100% with visible tumor, resolution 24%, regression 29%, stabilization 46%. If functional, biochemical control 86%, normalization 38%. OS 89%, due to disease progression 2 patients (Cushings)
  • Toxicity: Temporal lobe necrosis with headaches 1 patient (2%), new visual deficits 3 patients (23%), hypopituitarism 11 patients (30%), panhypopituarism 2 patients (5%)
  • Conclusion: Fractionated proton RT achieved effective radiologic, endocrinological, and symptomatic control; significant morbidity uncommon
• Lawrence Berkeley Laboratory
  • 1991 PMID 1808652 -- "Heavy-charged-particle radiosurgery of the pituitary gland: clinical results of 840 patients." (Levy RP, Stereotact Funct Neurosurg. 1991;57(1-2):22-35.)
    • Retrospective. 840 patients, 30 treated with protones, and 810 with helium ion. Pituitary tumors n=475 (59%), systemic disease treatment by inducing hypopituitarism n=365 (41%).
    • Outcome: Great majority marked and sustained biochemical and clinical improvement
    • Toxicity: Hypopituitarism in ~30%, focal temporal lobe necrosis ~1%
  • 1980 (1957-1978) PMID 7415170 Full paper -- "Treatment of acromegaly, Cushing disease and Nelson syndrome." (Lawrence JH, West J Med. 1980 Sep;133(3):197-202.)
    • Retrospective. 429 patients (acromegaly 72%, Cushing's disease 13%, chromophobe adenoma 8%, prolactin-secreting adenoma 4%, Nelson's syndrome 4%). Treated with alpha particles or protons. Dose ~60 Gy
    • Outcomes reported
• Harvard, 1968 (1963-1967) PMID 4966299 -- "Proton-beam therapy in acromegaly." (Kjellberg RN, N Engl J Med. 1968 Mar 28;278(13):689-95.)
  • Retrospective. 14/22 patients with acromegaly. Median time from onset to treatment 11.8 years. 5 prior RT therapy (36-40 rads). Proton dose typically 100-120 Gy (60-140 Gy), given 12 portals.
  • Outcome: 7/12 improved clinically, 3/12 unchanged, 2/12 worse.
  • Complications: Transient diplopia, H/A, anterior pituitary insufficiency