Abstract
Background Clinical behavior of pituitary neoplasms is peculiar and notoriously difficult to
predict. While aggressive tumors are common, metastasis is very rare, can be highly
delayed, and there are no histological or clinical features to meaningfully predict
this happening. Endocrinologically silent tumors are particularly difficult, as there
is less opportunity to detect early metastasis. Together, this amounts to a situation
of uncertainty over the appropriate management of such tumors before and after metastasis.
Case Description The authors report two cases of nonfunctioning aggressive pituitary adenoma (APA)
each requiring two transsphenoidal surgeries, a transcranial resection and radiotherapy.
Both these tumors subsequently metastasized caudally along the neuraxis, years later,
as a null cell carcinoma associated with a germline CHEK2 mutation and a silent Crooke's
cell carcinoma. The former represents a novel oncogenetic association.
Conclusion Delayed drop dural metastasis of pituitary carcinoma is becoming increasingly recognized.
Surgical resection of the distant disease to confirm the diagnosis and relieve the
mass effect, followed by temozolomide chemotherapy, is the current treatment of choice.
The need for both long-term follow-up in patients with APA, and a high degree of suspicion
toward dural-based radiographic findings is emphasized.
Keywords
pituitary carcinoma - pituitary adenoma - nonfunctioning - CHEK2 - Crooke's cell
