A 37‐Year‐Old Woman with Progressive Right Side Ptosis for One Month

Clinical History

A 37‐year‐old woman had bilateral blurred vision with hazy vision gradually from periphery to center for 2 months. There was mixed horizontal and vertical diplopia. Ophthalmologic treatment did not help. When she came to us, a Humphrey visual field test disclosed bilateral temporal hemianopia. CT showed hyperdensity and heterogeneously enhanced sellar lesion with size 2.57 × 1.96 × 3.63 cm and supra‐sellar extension. MRI also showed mixed intensity signals. MRI T2 scans showed compression of the optic chiasm. With contrast, there was heterogeneous enhancement in the tumor (Figure 1A). The clivus also showed T1 hyperintensity (Figure 1B).

Figure 1.

She underwent endoscopic endonasal tumor resection and the pathology showed a pituitary adenoma. Post‐Operative CT showed residual tumor at the sellar turcica (Fig 1C). There was central diabetic insipidus which improved after desmopressin treatment. She was then discharged. Unfortunately, one month later, she suffered from progressive diplopia, right side ptosis, impairment of right side visual acuity, with dizziness and headache. Follow‐up clinic visit revealed palsies in the right side optic nerve, oculomotor nerve, trochlear nerve and abducens nerve. Serial brain CT showed rapid progression of the sellar tumor with suprasellar extension and compression on the midbrain at 1 and 2 months after her initial operation (Figure 1D and E respectively). MRI T1 with enhancement disclosed strongly enhanced sellar tumor (Figure 1F). Laboratory data disclosed normal range of βhCG.

After discussion with patient and family, further surgical intervention was suggested. Operation of pterional approach and subtotal removal of the tumor was performed. Intra‐operatively, soft, yellowish and easy bleeding tumor was noted. After the operation, appropriate recovery condition with clear consciousness was noted for three weeks. After that, deterioration of the consciousness, irregular respiratory pattern and bilateral dilatation of the pupils without light reflex were noted since the 18th post‐operation day. After the second operation CT scan showed rapid regrowth of the tumor with suprasellar extension and brainstem compression (Figure 1G). On the 24th post‐operation day, we informed family the definite pathology diagnosis. After discussion with family, they decided to arrange supportive care to this patient. Then, this patient was expired on the 32th post operation day.

Microscopic Pathology

Histopathological examination revealed tumor cells with large, vesicular, rounded to bean‐shaped nuclei, prominent nucleoli and abundant cytoplasm, arranged in sheets or in a solid trabecular pattern (Figure 1H). The tumor cells are positive for EMA (Figure 1I), and the Ki‐67 labeling index is around 60% (Figure 1J). In addition, INI‐1 loss is also noted (Figure 1K). What is your diagnosis?

Diagnosis

Atypical Teratoid/Rhabdoid Tumor.

Discussion

Atypical teratoid/rhabdoid tumors (AT/RTs) are rare. Although 95% of these neoplasms occurred in the posterior fossa of children under the age of five years, ATRTs also occur rarely in adults where they largely manifest supratentorially. Since the first adult patient with a malignant CNS RT was reported in 1987, 54 adult cases (≥18 years of age) of malignant RT or AT/RT have been documented in the literature thus far 4. Occurrence of AT/RT in the sellar/suprasellar region is rare, with only nine cases reported so far.

At the first time of operation through the trans‐sphenoid approach, most of the specimen we got is normal pituitary glands. Due to rapid growth of the tumor in one month, another operation of pterional approach for subtotal tumor resection is performed. Pre‐operation differential diagnosis including pituitary carcinoma or carcinosarcoma, malignant meningioma, germ cell tumors, metastases and astrocytoma were impressed according to clinical and radiology result. At the microscopic level, the tumor is predominantly composed of rhabdoid cells with prominent nucleoli. Further immunochemistry staining disclosed positive results of EMA, VIM and HHF‐35 illustrated reactivity of the rhabdoid cells. Besides, INI‐1 loss is noted. According to WHO classification of tumors of the central nervous system, revised 4th edition, the pathologic result is an atypical teratoid/rhabdoid tumor. For the above condition, we presume that the normal pituitary gland might be pushed downward by the above rapid growing tumor, so the specimen we gather through the trans‐sphenoid approach is the normal tissue of the pituitary gland.

AT/RT is characterized by an aggressive clinical behavior in most pediatric patients, who usually die within approximately one year after the diagnosis despite aggressive therapy, while adult patients are reportedly better with some longer‐term survivors. A recent report suggest that cerebral location of an AT/RT renders the tumor amenable to gross total resection as well as aggressive adjuvant chemoradiation therapy available in adults, which would not be tolerated by small children. In the clinical observation, rapid growing with adjacent extension and distant metastasis after subtotal resection without immediate treatment due to absence of definite diagnosis at the first time of operation is noted 3. Early reports suggested that because of the young age of the patients and the large extent of the tumor at the time of diagnosis, total or near‐total resection could be obtained in less than one third of patients. In the data available in the registry, the overall median survival was 8.5 months; for 13 patients who had a gross total resection, the median event free survival was 14 months; for those with a lesser resection, the median event‐free survival was 7 months 2. The above condition reflects the fact that AT/RT show a greater tendency to disseminate intracranially and metastasize extracranially. Partial resection might make it possible to extend and metastasize 3.

A similar situation as our case is noted in the literature. A case diagnosed of pituitary macroadenoma after a previous endonasal transsphenoidal resection has recurrent headache and left cavernous sinus syndrome. Brain MRI also showed a tumor regrowth in the original location. Further operation of a near complete transsphenoidal resection of the sellar mass was performed followed by 3 months of stereotactic radiotherapy. The further histopathological diagnosis is AT/RT. This combined approach, performed before the final pathological diagnosis, allowed us to observe a better prognosis in the patient with a survival of 30 months 1. On the contrary, our patient should have better outcome if total resection of the tumor and early intervention of the radiotherapy were performed before the definite diagnosis which was confirmed 3 months later.

Although the case is rare, AT/RT should be considered in differential diagnosis of an unclear malignant sellar/suprasellar tumor in adults. There is no definite treatment protocol for AT/RT in adults. Optimal treatment including radical removal of the tumor combined with adjuvant radiotherapy and chemotherapy is an acceptable method considering better prognosis compared with AT/RT in young children.