Hormone-active intradural spinal metastasis of a prolactinoma--a case report

Long-term follow-up of growth hormone-producing pituitary carcinoma with multiple spinal metastases following multiple surgeries: case report

This report describes a rare case of a patient with growth hormone (GH)-secreting pituitary adenoma with malignant transformation resulting in multiple metastases to the dura mater of the cerebral convexity and high cervical spine. The patient was a 60-year-old man with a previous history of pituitary adenoma with suprasellar extension who had undergone transsphenoidal surgery, craniotomy for a convexity tumor, and suboccipital craniotomy for a cerebellar tumor. Thirteen years after the initial surgery, suboccipital craniotomy for a cervicomedullary junction tumor and cervicospinal surgery for a metastatic tumor was performed. Histologic findings of resected specimens demonstrated that the primary pituitary tumor was typical adenoma (similar to specimens from the initial surgery) but that the cerebellar and the dural tumor from the high cervical spine had a high incidence of mitotic figures, and cellular anaplasia with nuclear polymorphism and necrosis. In addition, the serum levels of GH were noted to have decreased with recurrence of the tumor. It was concluded that patients with pituitary adenoma, even when benign, must be carefully followed for signs of malignant transformation, and spinal or distant metastases.

Advances in the treatment of prolactinomas

Prolactinomas account for approximately 40% of all pituitary adenomas and are an important cause of hypogonadism and infertility. The ultimate goal of therapy for prolactinomas is restoration or achievement of eugonadism through the normalization of hyperprolactinemia and control of tumor mass. Medical therapy with dopamine agonists is highly effective in the majority of cases and represents the mainstay of therapy. Recent data indicating successful withdrawal of these agents in a subset of patients challenge the previously held concept that medical therapy is a lifelong requirement. Complicated situations, such as those encountered in resistance to dopamine agonists, pregnancy, and giant or malignant prolactinomas, may require multimodal therapy involving surgery, radiotherapy, or both. Progress in elucidating the mechanisms underlying the pathogenesis of prolactinomas may enable future development of novel molecular therapies for treatment-resistant cases. This review provides a critical analysis of the efficacy and safety of the various modes of therapy available for the treatment of patients with prolactinomas with an emphasis on challenging situations, a discussion of the data regarding withdrawal of medical therapy, and a foreshadowing of novel approaches to therapy that may become available in the future.

Pituitary carcinoma: a review of the literature

Pituitary carcinomas, defined as distant metastases of a pituitary neoplasm, are rare; fewer than 140 reports exist in the English literature. The initial presenting pituitary tumor is usually a secreting, invasive macroadenoma, with adrenocorticotropic hormone (ACTH)--and prolactin (PRL)--secreting tumors being the most common. The latency period between the diagnosis of a pituitary tumor and the diagnosis of a pituitary carcinoma is 9.5 years for ACTH-producing lesions and 4.7 years for PRL-secreting tumors. Survival after documentation of metastatic disease is poor; 66% of patients die within 1 year. Treatment options include additional surgery, radiotherapy, and chemotherapy, all of which are associated with poor results. Future studies will focus on identifying those invasive pituitary tumors most likely to metastasize and treating them aggressively before they progress to pituitary carcinomas.

Progression on metastatic neuroendocrine carcinoma from a recurrent prolactinoma: a case report

A 54 year old man was referred to the department of neurosurgery for frontal headache and vomiting. The patient was known in the department because of previous multiple surgery for a locally invasive pituitary prolactinoma (eight years, three years, and one year previously). The neurological examination revealed a frontal mass, which adhered to the dura, suggesting a meningioma. One year later, a left temporal metastasis was removed. Three months later, the patient died, with spinal metastases, of massive lung embolism. Histology revealed a progression of adenohypophyseal prolactinoma on neuroendocrine carcinoma, with an increase in proliferating indexes and modification of hormone production. This study documents a 10 year history of a rare prolactin producing pituitary carcinoma, which metastasised via liquoral flow.

Malignant prolactinoma: case report and review of the literature

BACKGROUND

Malignant prolactinomas are rare events. To date, only 14 patients with metastases in- or outside the central nervous system have been reported.

CASE DESCRIPTION

We present a patient who developed a metastasis to the cauda equina, which is the first case documented with MRI. A giant prolactinoma in this 51-year-old man was partially removed by a transcranial approach. After radiotherapy and treatment with bromocriptine, the patient had a remission for 3 years. Thereafter, a sacral intraspinal tumor was diagnosed. Because of increasing prolactin levels not responding to bromocriptine and a radiologically suspected intrasellar tumor, we operated transsphenoidally first and found only fibrous tissue. We performed a sacral laminectomy and almost totally removed an intradural tumor. Histopathology and immunohistochemistry confirmed the diagnosis of a prolactinoma metastasis. The patient received radiotherapy and bromocriptine and has no evidence of recurrent tumor or metastases after a follow-up of 38 months, thus being the second reported patient with long-term remission of the disease.

DISCUSSION

We review the literature on this topic and try to establish common features of the course of this rare malignant disease and the efficacy of therapy in the cases reported hitherto.

Pituitary Carcinomas

Pituitary carcinomas are defined by their metastatic growth. Most of them also invade into surrounding tissues. They should be classified by the site of their metastases (cerebrospinal, systemic, or combined) and by the presumable cell type of origin, respectively with the hormone being demonstrable by immunohistochemistry (adrenocorticotrophic hormone [ACTH], prolactin [PRL], growth hormone [GH], hormone-negative). Pituitary carcinomas develop from invasive adenomas. Nearly all tumors had been treated by surgery or X-ray before they metastasized. Since 1976, 37 cases demonstrated with modern methods were reported: 23 had metastasized into the brain or meninges, 10 showed extracerebral metastases, and 4 showed both types of metastases. In our collection of pituitary tumors, three carcinomas (0.13%) were identified: two with systemic metastases (one ACTH secreting and one PRL secreting) and one with meningeal dissemination and ACTH production. The diagnosis of pituitary carcinomas should be based on four criteria: a demonstrable metastasis, identification of the primary tumor as a pituitary tumor, similarity between the structure and immunohistological marker expression of metastasis and primary tumor, and exclusion of an alternative primary tumor.

Gonadotropic pituitary carcinoma: case report

A 37-year-old man developed multiple intracranial, intraspinal, and general metastases from an invasive nonfunctioning pituitary adenoma after surgery and radiation therapy. This is the first gonadotropic pituitary carcinoma reported in literature.

Intracranial dissemination of a macroprolactinoma

A patient with a macroprolactinoma and extrasellar extension was treated by incomplete transfrontal surgery, external irradiation and additional bromocriptine (Br) treatment. After 4 years, partial bromocriptine resistance developed (a rare occurrence) together with the appearance of intracranial metastases. 123I-Iodobenzamide was helpful in evaluating the dopamine D2 receptor status of the metastatic tumour both in vivo using single-photon emission computed tomography (SPECT) and in vitro. Prolactin release by the cultured metastatic tumour cells was more potently inhibited by CV 205-502 than by bromocriptine. The patient, treated by surgery, irradiation and CV 205-502, developed a ptosis of the left eye and a transient psychiatric delusional state, the latter probably an effect of the dopamine agonist. As the right frontal metastasis was markedly positive on SPECT with 111In-SMS, somatostatin treatment was added to the CV 205-502.

Malignant prolactinoma with extracranial metastases: a report of three cases

OBJECTIVE

Prolactin-secreting tumours of the pituitary almost never metastasize extracranially. However, we have recently seen three such patients, whose presentation, clinical course and response to treatment are reviewed in order to determine whether they possess unique clinical features, and to assess optimum therapy.

DESIGN AND PATIENTS

Three patients with extracranial metastases from prolactinomas have been retrospectively reviewed.

MEASUREMENTS

Clinical courses, biochemical parameters and imaging modalities (CT, MR and radiolabelled somatostatin analogue scanning) and histopathology were assessed before and during different therapeutic regimens.

RESULTS

All three patients' presentations were initially unremarkable, but later each had persistent and relentlessly increasing serum prolactin concentrations and evidence of distant spread of their tumours. The first patient presented aged 32 and was treated with repeated transsphenoidal resections of the tumour, pituitary radiotherapy, high dose bromocriptine therapy, the somatostatin analogue octreotide and chemotherapy. Nine years after the original diagnosis a liver biopsy revealed carcinoma cells positively immunostaining for prolactin. At autopsy further microscopically similar metastases were seen in both lungs and the left hilar lymph nodes. The second patient presented aged 48 and was treated with external beam pituitary radiotherapy, bromocriptine, transsphenoidal hypophysectomy and chemotherapy. Fifteen years after the original diagnosis bone biopsy revealed carcinoma cells positively immunostaining for prolactin; the patient developed interstitial nephritis and died in renal failure. The third patient presented aged 48 with hypogonadism and bitemporal hemianopia due to a macroadenoma. This was removed transfrontally and followed by external beam radiotherapy. After recurrence, further surgery and radiotherapy were undertaken, but the tumour continued to grow and the patient died suddenly of a pulmonary embolus. At autopsy, tumour was found in thoracic lymph nodes and lung capillaries.

CONCLUSIONS

These three patients may be added to the previous two reported cases of malignant prolactinoma with extracranial spread. Several different therapies were tried but were of limited value in controlling the progression of the disease, although chemotherapy is an important modality to be considered. No particular factor or combination of factors at presentation differentiated these patients from more typical patients whose disease is much less aggressive.