Pathological changes after radiotherapy for primary pituitary carcinoma: a case report

Corticotrophic pituitary carcinoma with cervical metastases: case series and literature review

PURPOSE

Pituitary tumors are the second most common intracranial tumors, however, pituitary carcinoma is a rare clinical entity which represents only 0.1-0.2% of all pituitary tumors. Diagnosis of pituitary carcinoma requires the presence of metastasis. Early identification of pituitary carcinoma is difficult, and only recently have guidelines been published for the treatment of aggressive pituitary tumors. We present two cases from our institution, with a review of other cases available in literature in order to better characterize this rare disease.

METHODS

A retrospective review of two patients with pituitary carcinoma treated at a tertiary medical center was performed. The MEDLINE database was searched for all cases of pituitary carcinoma. Information for age at diagnosis, sex, pituitary tumor type, latency period from pituitary tumor to presentation of carcinoma, sites of metastasis, number of surgical therapies, radiation and chemotherapy, and survival after diagnosis were collected.

RESULTS

A total of 69 studies were available for review for a total of 72 unique cases. The average age at diagnosis was 46.3 years. The most common tumors were ACTH-secreting (34.7%), Prolactin-secreting (23.6%), and Null Cell (15.3%). The average latency period from pituitary tumor diagnosis to metastasis was 9 years. All patients underwent surgical therapy during their treatment, with an average of 2.76 procedures. The mortality rate was 54.8% with average time to death after diagnosis of approximately 10 months.

CONCLUSIONS

Pituitary carcinoma is a rare disease with high mortality rate and is a diagnostic and treatment challenge. Further study is required but is difficult due to its low incidence.

Orbital metastasis of pituitary growth hormone secreting carcinoma causing lateral gaze palsy

Background:

Although pituitary adenoma is one of the most common intracranial tumors, it rarely progresses secondarily into a metastatic carcinoma. Commonalities in reported cases include subtotal resection at presentation, treatment with radiation therapy, and delayed metastatic progression. Pathologic descriptions of these lesions are varying and inconsistent.

Case Description:

A 52-year-old male was diagnosed with acromegaly and pituitary tumor in 1996. He underwent four subtotal resections and five courses of stereotactic radiosurgery over 14 years. He developed left eye lateral gaze palsy, and was found to have a distant orbital metastasis with involvement of the left lateral rectus and lateral orbital wall. He underwent left orbital craniotomy via eyebrow incision for resection of this lesion. Pathologic evaluation showed a markedly elevated Ki67 level of 30%.

Conclusion:

While overall incidence of metastatic progression of pituitary adenoma after radiotherapy appears to be low, it appears to be a possible complication, and could be more likely in patients receiving multiple doses of radiotherapy. Our review of reported cases showed that 45/46 (97.8%) of patients developing carcinoma had prior radiation exposure. These patients may also have more aggressive pathologic characteristics of their lesions.

Pituitary carcinoma with mandibular metastasis: a case report

Pituitary carcinomas are rare primary adenohypophyseal tumors with cerebrospinal or extracranial metastasis. The present case, the first report of the disease in Korea, involved a 36-yr-old woman who presented with a 3-week history of headache. Brain magnetic resonance imaging revealed a 2.5-cm sellar and suprasellar mass showing heterogeneous enhancement with suspicious invasion of both cavernous sinuses. The patient underwent gross-total resection. The tumor cells were composed of polygonal cells singly or in variable-sized nests. The nuclei were large and round with prominent nucleoli. The cytoplasms was acidophilic and granular. Marked pleomorphism and frequent mitoses (3 per 10 HPFs) were found. By immunohistochemistry, tumor cells were strongly positive for prolactin, but negative for ACTH and GH. Additional immunostainings for cytokeratin, vimentin, and glial fibrillary acidic protein (GFAP) were negative. After the surgery, the patient received radiotherapy because of the atypical histologic features. The prolactin level fell from 123.17 ng/mL to 5.17 ng/mL after surgery. Nine months after the initial diagnosis, the patient died from mandibular metastasis associated with the pituitary carcinoma.