Successful treatment of medically and surgically refractory lymphocytic hypophysitis with fractionated stereotactic radiotherapy: a single-center experience and systematic literature review.

PURPOSE: To explore the potential role of focused radiotherapy in managing the lymphocytic hypophysitis (LH) refractory to medical therapy and surgery. METHOD: A systematic literature review was conducted following PRISMA guidelines to identify the studies on radiation treatment for hypophysitis, along with the experience in our institution. RESULTS: The study included eight patients, three from our institution and five from existing literature. The age at presentation ranged from 37 to 75 years old, with a median age of 58. The presenting symptoms involved headache in seven patients and diplopia in two patients. Pre-radiation visual field defects were noticed in four patients. All patients exhibited variable degrees of hypopituitarism before radiation, with oral corticosteroids being the initial medical treatment. Immunosuppressive therapy was attempted in two patients prior to radiation. Seven patients had a history of transsphenoidal surgery with a histologically confirmed LH. Three patients underwent stereotactic radiosurgery (SRS), while the remaining received FSRT, with a mean irradiation volume of 2.2 cm3. A single-session total dose of 12 -15 Gy was administered in the SRS group. In the FSRT group, doses ranged from 24 to 30 Gy with a median dose of 25 Gy, delivered in 2 Gy fractions. Four patients achieved a resolution of visual field defects, while another two patients demonstrated improvement in their associated focal neurologic deficits. No change in pre-existing endocrine status was shown after radiation, except in one patient. Clinical response was achieved in seven patients after a single course of radiation, while one patient required the second course. Six patients remained stable on low-dose glucocorticoid during at least a 12-month follow-up period, and one discontinued it entirely without experiencing relapse. Three patients demonstrated a complete radiologic response, while the remaining showed a partial radiologic response. CONCLUSIONS: Focused radiation, including FSRT, can play a role in symptomatic relief, effective mass shrinkage, and minimizing radiation exposure to critical surrounding structures in patients with refractory LH. However, further research efforts are necessary to better clarify its effects and optimal dose planning.

Lymphocytic Hypophysitis Successfully Treated with Stereotactic Radiosurgery: Case Report and Review of the Literature.

Lymphocytic hypophysitis (LH) is an autoimmune inflammatory infiltration of the pituitary gland, usually with a benign evolution. In rare circumstances the inflammatory process may extend beyond the pituitary and infiltrate the surrounding structures. We present a 42-year-old woman affected by an aggressive form of LH with extension to the cavernous sinus causing internal carotid artery occlusion and right sixth cranial nerve palsy. Prednisone therapy caused severe iatrogenic Cushing's syndrome, and the patient underwent transsphenoidal decompression. The histopathology report was consistent with LH. The patient was symptom free for a short period with reappearance of severe headache, diplopia, and hearing loss (middle ear inflammation) 3 months after surgery. Corticosteroids were reintroduced with the addition of azathioprine, but there was no regression of the pituitary mass. The patient was referred for stereotactic radiosurgery (SRS) using Gamma Knife (15 Gy to the margin). After 26 months, azathioprine was stopped, and the dose of prednisone was gradually tapered to 7.5 mg/day. Sellar magnetic resonance imaging showed regression of the pituitary mass. After follow-up for > 3 years after SRS, there was no clinical or radiologic evidence of the disease, but carotid arteries remained occluded. The patient developed secondary hypothyroidism and hypogonadism as consequences of SRS. An aggressive form of LH extending beyond the pituitary gland infiltrating surrounding structures is described. It was successfully treated with SRS after failure of transsphenoidal surgery and combined immunosuppressive therapy (prednisone, azathioprine). The review of the literature presents timely information concerning treatment with azathioprine and SRS of patients with an aggressive form of LH.