Pediatric soft-tissue tumors

Soft-tissue tumors in children (<18 years) are a heterogeneous group of lesions. Masses may be asymptomatic or associated with pain or discomfort. Although most lesions are benign, developing an appropriate differential diagnosis requires knowledge of the clinical and radiographic characteristics of tumors and tumorlike conditions in children. A thorough history and physical examination, followed by appropriate imaging studies, when indicated, can establish a correct diagnosis and help determine appropriate treatment recommendations.     

Pediatric glomus tumors

Glomus tumors of the middle ear are unusual in adults, but exceedingly rare in children. While a dull, red bulging tympanic membrane in the adult may suggest a glomus tumor, it generally signifies infection in the child. This report details our management of a 10-year-old girl afflicted with bilateral chronic middle ear cleft infection that obscured bilateral glomus tumors. Review of the current English language literature reveals seven additional case reports of otologic glomus tumors in children less than fourteen years of age. Two additional cases are presented that were given to the senior author by personal communication, producing a total of 10 cases for review. Glomus tumors in children may be hidden by otitis media and appear more likely to be endocrine active. Failure to cure the lesion is apparent in five of six case reports of children with glomus jugulare tumors; three of these children are reported to have expired. Complete surgical extirpation is advocated for childhood glomus tumors.     

Pathology of pituitary tumors

Pituitary adenomas are benign neoplasms originating in adenohypophysial cells. They represent the most common neoplasm of the sellar region, comprising approximately 15% of all primary intracranial tumors. Depending on the studies of unselected adult autopsy material, their frequency as an incidental finding varies between 5% and 20%. The first part of this article summarizes the immunohistochemistry of nontumorous human adenohypophysis. In the second part, the classification of pituitary tumors is discussed, followed by the immunohistochemical and electron microscopic findings of pituitary adenomas and pituitary carcinomas.     

Conventional radiotherapy for pituitary tumors

Radiosurgery for pituitary adenomas is clearly attaining a more prominent position in the spectrum of management of these lesions. It is our belief that improvements in radiosurgical technology can significantly enhance the outcome for patients with these lesions.     

Surgical approaches to pituitary tumors

The transnasal transsphenoidal technique is the preferred approach for pituitary tumors confined primarily to the sella and parasellar regions. In the hands of experienced pituitary surgeons, the rates of morbidity and mortality are extremely low. Extended transsphenoidal approaches have been applied to gain access to the cavernous sinus and suprasellar regions. In some cases, resection via a transcranial approach may be warranted. Endoscopic techniques are being increasingly used and offer a minimally invasive approach and further reduce morbidity associated with the approach to pituitary tumors.     

Pediatric spinal axis tumors.

Pediatric spinal cord tumors occur in the intramedullary or extramedullary spaces. The extramedullary tumors are further divided into those in intradural-extramedullary or extradural locations. Tumors in the intradural-extramedullary region include nerve sheath tumors, meningiomas, and "embryonal" tumors. In the extradural space are neuroblastomas, sarcomas, and other primary tumors of bone. The radiographic findings, histology, and management of each type of tumor are included in this article, which focuses on extramedullary tumors.     

Microsurgical management of giant pituitary tumors

Pituitary turnors with large suprasellar extensions are a difficult surgical challenge. A series of 11 patients with giant pituitary adenomas is reported. Seven men and four women (mean age 54.1 years). were diagnosed following a mean duration of symptoms of 60 months, Common presenting symptoms included visual disturbances, headache, personality changes, and panhypopituitarism. A single patient presented with rapid onset of coma and oculomotor nerve palsy. Eight patients underwent a transsphenoidal approach, and three patients underwent a craniotomy as the initial surgical procedure. A total of 16 surgical procedures were performed, resulting in complete or near complete resection in seven patients, and partial removal in four. Six patients had a good outcome and one patient in poor condition prior to surgery was unchanged postoperatively. One patient was worse following surgery, and there were two operative deaths. These tumors have a consistency and a propensity to adhere to neurovascular structures, making complete surgical resection difficult. Management should be individualized and should be based upon the radiographic and clinical features of the tumor. We feel that most leslons are best approached initially transsphenoidally, unless there is significant lateral extension. In many patients, aggressive surgery is not indicated and limited subtotal transsphenoidal resection followed by irradiation is recommended. Surgical decision making and strategy is discussed in relation to our recent experience with giant pitnitary adenomas.     

Medical treatment of functional pituitary tumors

Medical therapy with a dopamine agonist is the most effective for treatment of a prolactin-producing adenoma and is considered as primary treatment. Surgery and pituitary radiation are reserved for patients who either do not tolerate or do not respond to a dopamine agonist drug. A somatostatin analogue is effective medical therapy for patients with acromegaly, and this is usually administered if there is persistent GH hypersecretion after surgical resection. Medical treatment for patients with Cushing's disease is directed at the adrenal glands to reduce cortisol hypersecretion. Unfortunately, there is no effective medical therapy to reduce pituitary corticotropin production. Medical therapy for a gonadotrope adenoma with a dopamine agonist or somatostatin analogue has limited utility but is employed in patients who are unable to undergo surgery and may delay or prevent additional tumor growth. Many patients with a pituitary adenoma can be successfully treated with one treatment, either a dopamine agonist for a prolactinoma or surgery for other types of tumors. A substantial number of patients require multimodality therapy, however, including medical therapy, surgery, and pituitary radiation. Because the biologic behavior of pituitary adenomas varies considerably, a patient with a pituitary adenoma requires lifelong regular monitoring for hormone hypersecretion, tumor recurrence, and development of new pituitary hormone deficiency. A coordinated plan of care among endocrinologists, neurosurgeons, neuroophthalmologists, and radiation therapists is necessary to provide optimal care for these patients.     

Postoperative endocrine management of pituitary tumors

Pituitary tumors are common and are often associated with endocrine abnormalities. Furthermore, pituitary surgery itself may result in additional hormonal changes, including impairment of anterior pituitary hormone secretion and, more commonly, abnormalities of ADH regulation. Endocrine management of patients with pituitary or other sellar lesions involves acute hospital-based and longer term office-based evaluation and treatment. In the immediate postoperative period, careful attention must be directed toward sodium and water balance as well as toward recognition of changes in endocrine function. Postoperative measurement of serum hormone levels also helps to determine if resection of a hypersecreting tumor has been successful. To minimize postoperative morbidity, perioperative endocrine assessment and management of patients undergoing pituitary surgery should consist of a team approach, involving both the neurosurgeon and the endocrinologist.     

Transsphenoidal extracapsular approach to pituitary tumors

Two years' experience with an extracapsular transsphenoidal approach to pituitary adenomas is presented. Some pituitary tumors contain an inordinate amount of connective tissue that often makes transsphenoidal resection difficult. By opening the tumor capsule and adjacent arachnoid membrane, such tumors with suprasellar extension can be safely removed. In some cases of functioning adenoma, resection of the diaphragma sellae and adjacent arachnoid membrane results in hormonal control. Among 62 cases of transsphenoidal surgery for pituitary adenomas, eight cases required this procedure. The surgical procedure is described and the cases are summarized. The indication and limitations of this procedure are discussed.     

Radiosurgery for pituitary tumors and craniopharyngiomas

Standard techniques of conventional radiation therapy have been used for many years to treat pituitary adenomas and craniopharyngiomas. These techniques are not always effective and carry with them morbidity in the form of damage to the normal pituitary gland, damage to the hypothalamus, the potential of damage to the visual system and to intellectual functions of the brain and a small but real risk of the development of secondary malignancies. In an effort to avoid these complications and to provide more effective adjunctive radiation therapy, techniques of stereotactic delivery of high-dose radiation to the pituitary region have been developed, known as radiosurgery. The history of the development of radiosurgery and its application to pituitary problems are recounted in this article, as are a number of the controversies that currently exist and need to be considered as these modalities of stereotactic radiosurgery are applied more frequently and to better effect in the future.