Stereotactic radiosurgery as the initial management option for small-volume hypothalamic hamartomas with intractable epilepsy: a 35-year institutional experience and systematic review

OBJECTIVE

Young patients with hypothalamic hamartomas (HHs) often present with intractable epilepsy. Currently there are no established management guidelines for HH. The authors retrospectively reviewed their single-institution experience to delineate the role of stereotactic radiosurgery (SRS).

METHODS

Seven patients with HHs (4 females; median age 13.7 years, range 2.5-25 years) with no prior resection underwent SRS between 1987 and 2022. The clinical history, epilepsy profile, radiographic findings, and neurological outcomes were characterized. HH topographical types were classified according to the Régis classification. Outcome measures included Engel seizure classification, HH response, and the need for additional surgical interventions.

RESULTS

All patients had Engel class IV epilepsy. A Leksell Gamma Knife was used to deliver a median margin dose of 18 Gy (range 16-20 Gy) to a median hamartoma volume of 0.37 cm3 (range 0.20-0.89 cm3). Seizure reduction was confirmed in 6 patients, and 2 patients had regression of their hamartoma. Two patients underwent resection and/or laser interstitial thermal therapy after SRS. At follow-up, 1 patient was seizure free, 4 patients achieved Engel class II, 1 patient had Engel class III, and 1 patient had Engel class IV seizure outcomes.

CONCLUSIONS

SRS as the initial management option for HH was associated with a low risk of adverse effects. In this institutional series reviewing small-volume HHs treated with SRS, no adverse radiation effect was detected, and the majority of patients experienced seizure reduction. SRS should be considered as the first-line treatment for seizure control in patients with small-volume HHs.

Risk-adapted, long-term management in childhood-onset craniopharyngioma

PURPOSE

This report is a review of findings on the diagnosis, treatment, clinical course, follow-up, and prognosis of craniopharyngioma patients with special regard to clinical trials and long-term management.

METHODS

Literature search on Pubmed for paper published after 1994.

RESULTS

Craniopharyngiomas are rare, embryonic malformations of the sellar/parasellar region with low histological grade. Clinical manifestations are related to increased intracranial pressure, visual impairment, and hypothalamic/pituitary deficiencies. If the tumor is favorably localized, therapy of choice is complete resection, with care taken to preserve hypothalamic and optic functions. In patients with unfavorable tumor location (i.e. involvement of hypothalamic areas), recommended therapy is limited hypothalamus-sparing surgical strategy followed by irradiation. Irradiation has proven effective in treatment of recurrences and progression. Surgical lesions and/or anatomical involvement of posterior hypothalamic areas can result in serious sequelae, mainly hypothalamic syndrome.

CONCLUSIONS

It is crucial that craniopharyngioma be managed as a frequently chronic disease, providing ongoing care of pediatric and adult patients' by experienced multidisciplinary teams in the context of multicenter trials.

Interstitial radiosurgery in the treatment of gelastic epilepsy due to hypothalamic hamartomas

The authors evaluated a new stereotactic radiosurgical approach in seven patients with gelastic epilepsy due to hypothalamic hamartomas. Stereotactic implantation of 125I-seeds into the hamartoma was feasible in six patients. At follow-up at least 1 year after interstitial radiotherapy, two patients had become seizure-free within 2 months, and two others had only persisting auras. There were no major perioperative or postoperative side effects.

Langerhans cell histiocytosis limited to the pituitary-hypothalamic axis--two case reports

Langerhans cell histiocytosis rarely presents as a solitary lesion in the pituitary-hypothalamic region, and is indistinguishable from germinoma, which occurs much more frequently, especially in Japanese. A 14-year-old girl and a 9-year-old girl presented with polydipsia and polyuria as the initial symptoms. Magnetic resonance (MR) imaging demonstrated a round mass at the pituitary stalk appearing as isointense on T1-weighted imaging and hyperintense on T2-weighted imaging. Endocrinological examination revealed mild hypopituitarism with central diabetes insipidus. Both patients underwent open craniotomy. Histological examination revealed granulomatous tissue with eosinophil infiltration and frequent Langerhans histiocyte clustering, compatible with the diagnosis of Langerhans cell histiocytosis. Low-dose local irradiation of 20 Gy was administered. First patient was followed up for 8 years, and her hypopituitarism gradually improved to a minimal level with only amenorrhea as the residual symptom. Recent MR imaging showed no residual mass at the region. Second patient was followed up for 15 months, and her diabetes insipidus is stable. MR imaging performed 5 months after the treatment showed marked reduction of the mass. These cases reemphasize the importance of histological diagnosis for lesions with similar neuroimaging appearances. Biopsy and low-dose irradiation are an effective treatment for this rare and essentially benign lesion, as opposed to attempting total removal of the mass.

Neurosarcoidosis presenting as hypopituitarism and a cystic pituitary mass

We report a young woman with clinical hypopituitarism and systemic sarcoidosis involving the lung, gastrointestinal tract, and peripheral lymph nodes. Laboratory evaluation confirmed that cortisol, thyroid indices, insulin-like growth factor 1, follicle-stimulating hormone, luteinizing hormone, and estradiol levels were low, with a normal prolactin. Magnetic resonance imaging revealed a large cystic pituitary lesion compressing the optic chiasm and exhibiting rim but not hypothalamic enhancement. The differential diagnosis included cystic macroadenoma, Rathke's cleft cyst, craniopharyngioma, and simple cyst. A transsphenoidal procedure provided decompression and diagnosis: pathology was consistent with sarcoidosis. Postoperatively, the patient's neurosarcoid disease markedly worsened, requiring hypothalamic irradiation. To our knowledge, this is the first report of intracranial sarcoidosis presenting solely as a cystic pituitary mass. An awareness of this possibility is important to prevent inappropriate neurosurgical intervention and subsequent potential exacerbation of neurosarcoidosis.

Hypothalamic histiocytosis X with diabetes insipidus and Korsakoff's syndrome--case report

A 54-year-old female presented with apparent isolated hypothalamic histiocytosis X associated with diabetes insipidus and Korsakoff's syndrome. Computed tomographic and magnetic resonance imaging demonstrated a single hypothalamic mass. A craniotomy for biopsy found granulation tissue of unknown cause. Further investigation discovered genital bleeding before admission. Biopsy of the cervix uteri revealed histiocytosis X. Further studies showed the disease was restricted to the hypothalamus and the endometrium of the cervix uteri. Low-dose irradiation led to partial regression of the hypothalamic mass and improvement of Korsakoff's syndrome. Even when a diagnosis of isolated hypothalamic histiocytosis X is confirmed, the possibility of another histiocytosis X lesion in an unexpected region must be considered.

Plasma cell granuloma of the hypothalamic region

Two patients suffering from diabetes insipidus, with additional symptoms of impaired vision and signs of panhypopituitarism and increased intracranial pressure, showed a normal sella tursica in the X-ray examination of the skull but large, dense space-occupying lesions in the hypothalamus on CT scans of the brain. NMR performed in one patient disclosed suprasellar growth of a hypothalamic lesion. Proliferation of lymphoplasmocytes and mature plasma cells was seen by light microscopic and electromicroscopical examination of biopsy samples in both cases; histiocytes and multinucleated giant cells were absent; tuberculosis, syphilis and sarcoidosis were ruled out by appropriate tests. Plasma cells exhibited polyclonal immunoglobulin expression as revealed by immunocytochemistry using the PAP method. Taken together these features are typical of plasma cell granuloma. Transitory remission after radiotherapy was obtained in one patient.

Histiocytosis X of the hypothalamus

An 18-year-old woman presented with visual disturbance and endocrine dysfunction (diabetes insipidus, delayed puberty, hypothyroidism, hypoadrenalism, and hyperprolactinemia). Computed tomography and enhanced cisternography showed a single hypothalamic mass, which proved at biopsy to be histiocytosis X. Further studies showed the disease to be restricted to the hypothalamus. The patient was treated with hormonal replacement therapy, but her visual acuity continued to worsen. Visual acuity improved after low-dose irradiation of the pituitary fossa and hypothalamus, which also led to disappearance of the mass. This case shows that localized hypothalamic histiocytosis X can be diagnosed and treated successfully before other systems become involved.