Background: Cerebellar metastasis (CM) from papillary thyroid carcinoma (PTC) is exceptional with only 12 reported cases and usually carries a very poor prognosis. In the two previously reported patients in whom CM was detected before PTC, other distant or local metastases were already present by the time of PTC diagnosis. We report a patient found to have papillary thyroid microcarcinoma after surgical resection and histopathological study of a large solitary hemorrhagic CM, who showed no evidence of other metastatic sites and survived 7 years after initial diagnosis.
Summary: A 65-year-old female patient with a history of surgical resection of a 7-cm cerebellar mass diagnosed with PTC metastasis, and adjuvant treatment with cranial external radiotherapy, was referred to us. The neck ultrasonography showed a solitary 4-mm right thyroid nodule. Histopathology after total thyroidectomy revealed a 2-mm papillary thyroid microcarcinoma, sclerosing variant, with capsule infiltration but no regional lymph node invasion. Although she received a total dose of 500 mCi of 131-I after surgery and the last two whole-body scans were normal, serum thyroglobulin levels progressively increased. The patient refused any further test or treatment other than basal blood sampling and suppressive therapy with levothyroxine and remained stable for 4 years until she started to complain about deviation of her walk. A computed tomography scan showed a regrowth of the metastasis. She suffered a sudden worsening of her neurological status because of a big intratumoral hemorrhage that required decompressive craniectomy and hematoma evacuation surviving 3 years more after this episode.
Conclusions: To our knowledge, this is the first reported case of a solitary CM from an occult PTC, and also the first that developed an acute cerebellar hemorrhage years after cranial surgery, however, exhibiting the longest reported survival. This case highlights the importance of not only an appropriate initial treatment of the CM and primary PTC in these patients, but also a close follow-up, to avoid further complications and improve their prognosis.