An acute adrenal insufficiency revealing pituitary metastases of lung cancer in an elderly patient

Pituitary metastasis of lung adenocarcinoma: Case report and literature review

•

Pituitary metastasis is rare, and it is the least common intracranial site of metastases.

•

Majority of cases of pituitary metastasis the patient is known to have a primary malignancy.

•

The clinical presentation and radiological features of pituitary metastasis are not specific making diagnosis difficult.

•

Management may include endoscopic trans-sphenoidal resection, chemotherapy, radiotherapy and hormone replacement.

•

Definitive diagnosis can be achieved through surgical resection.

Introduction

Pituitary metastasis is rare, and it is the least common site of intracranial metastases. It is mostly asymptomatic but can present with diabetes insipidus, headache, ophthalmoplegia, visual disturbance and anterior pituitary dysfunction and in majority of cases patients known to have a primary malignancy.

Case Presentation

This study presents a 54-year-old male presented with a few months history of headache and drooping of both eyelids and after proper investigations and endoscopic resection of the sellar mass the diagnosis was confirmed to be pituitary metastasis of lung adenocarcinoma.

Conclusion

Diagnosis and management of pituitary metastases are complex and depend on many factors. Endoscopic surgical resection and debulking alleviates symptoms and provides the definitive diagnosis which has great importance in cases with clinical presentation that does not strongly point to pituitary metastasis to avoid unnecessary radiotherapy and chemotherapy when possible.

Diabetes insipidus and panhypopituitarism as a first presentation of silent adenocarcinoma of lung: a case report and literature review

BACKGROUND

Pituitary metastasis is a rare condition with a poor prognosis. Very few patients with pituitary metastasis are symptomatic. It is often associated with presence of co-existing metastases to other organs. Isolated pituitary metastasis as the first presentation of primary malignancy is uncommon.

CASE PRESENTATION

A 72-year-old woman presented with a 2-month history of polyuria, increasing thirst and unexplained weight loss. Esophagogastroduodenoscopy (EGD) was scheduled as part of the investigation. She was kept nil per os for 10 h prior to EGD, after which she developed alteration of consciousness. Further investigation revealed hypernatremia with sodium level of 161 mmol/L and low urine osmolality of 62 mOsm/kg. Her urine output was 300 mL per hour. Diabetes insipidus (DI) was diagnosed based on evidence of polyuria, hypernatremia, and low urine osmolality. Her urine output decreased and urine osmolality increased to 570 mOsm/kg in response to subcutaneous desmopressin acetate, confirming central DI. Pituitary magnetic resonance imaging showed a heterogeneous gadolinium enhancing lesion at the sellar and suprasellar regions, measuring 2.4 × 2.6 × 3.9 cm compressing both the hypothalamus bilaterally and the inferior aspect of optic chiasm as well as displacing the residual pituitary gland anteriorly. The posterior pituitary bright spot was absent. These MRI findings suggested pituitary macroadenoma. There were also multiple small gadolinium-enhancing lesions up to 0.7 cm in size with adjacent vasogenic brain edema at the subcortical and subpial regions of the left frontal and parietal areas, raising the concern of brain metastases. Pituitary hormonal evaluation was consistent with panhypopituitarism. Histopathological and immunohistochemical studies of the pituitary tissue revealed an adenocarcinoma, originating from the lung. Computed tomography of the chest and abdomen was subsequently performed, showing a 2.2-cm soft tissue mass at the proximal part of right bronchus. There was no evidence of distant metastases elsewhere. The final diagnosis was adenocarcinoma of the lung with pituitary metastasis manifesting as panhypopituitarism and central DI. Palliative care along with hormonal replacement therapy was offered to the patient. She died 4 months after diagnosis.

CONCLUSION

Diagnosis of pituitary metastasis is challenging, especially in patients with previously undiagnosed primary cancer. It should be considered in the elderly patients presenting with new-onset central DI with or without anterior pituitary dysfunction.

Small Cell Lung Cancer with Pituitary Metastasis Presenting as Secondary Adrenal Insufficiency: A Case Report and Literature Review

BACKGROUND Pituitary gland metastasis is rarely the initial presentation of metastatic cancer. Most cases of pituitary gland metastasis are asymptomatic with diabetes insipidus being the most common symptomatic presentation. It can rarely present with symptoms of hormone underproduction such as secondary adrenal insufficiency. Although pituitary gland metastasis is rare, it is underestimated, as it is commonly misdiagnosed with pituitary gland adenoma due to the lack of clear radiological criteria differentiating between both. CASE REPORT We present a case of a 62-year-old male who presented with weakness, blurry vision, and persistent hypoglycemia despite intravenous dextrose infusion and having discontinued taking his diabetes medications. Chest x-ray showed a left hilar mass, while computed tomography scan demonstrated a left superior hilar mass and hilar lymphadenopathy with bilateral adrenal nodules and a T6 vertebral lesion suspicious for metastasis. Further workup showed secondary adrenal insufficiency with a low adrenocorticotropic hormone (ACTH) level. Vertebral biopsy was performed and confirmed the diagnosis of small cell carcinoma of the lung. This was followed by a brain magnetic resonance imaging (MRI), which showed multiple metastatic lesions with an enhancing mass involving the right clivus, sella, and suprasellar cistern with mass effect on the optic chiasm and involvement of the cavernous sinus supporting the diagnosis of pituitary gland metastasis of small cell lung cancer. The patient received brain radiation, and repeated MRI showed regression of the previous MRI findings. CONCLUSIONS Secondary adrenal insufficiency is an unusual presentation of pituitary gland metastasis. Physicians should take into consideration both radiological findings and presentation to differentiate between pituitary gland metastasis and pituitary adenoma.

Pituitary metastasis: a rare condition

Tumor metastasis to the pituitary gland is a life-threatening condition associated with short life span. Pituitary metastasis is rare, however, and not well-documented. A better understanding of its clinical manifestations could lead to earlier diagnosis, appropriate therapy, and potentially improving quality of life. Therefore, we retrospectively studied the charts of patients with pituitary metastases who were treated at the City of Hope National Medical Center in Duarte, California, from 1984 to 2018. We reviewed and analyzed tumor origin, primary pituitary clinical manifestation, duration between primary tumor diagnosis and pituitary metastasis, type of treatment, and patient survival. A total 11 patients with a mean age of 59.2 years and median survival of 50.33 months were identified. Breast cancer and lymphoma were the most common primary origins in these cases, and diabetes insipidus and panhypopituitarism were the most common primary manifestations of their metastasis. We also compared our results with reports in the literature published between 1957 and 2018. A total 289 patients with pituitary metastasis have been reported in the literature. Breast cancer was the most frequent primary origin of the metastasis, and visual involvement was the most common primary manifestation. The posterior part of the pituitary is more susceptible than the anterior to metastasis. Pituitary metastasis may occur as a consequence of successful primary tumor treatment prolonging the chance of seeding. Future studies are needed to determine the molecular mechanism of metastasis to the pituitary.