Alveolar rhabdomyosarcoma of the clivus with intrasellar expansion: Case report

Endoscopic Endonasal Surgery for Uncommon Pathologies of the Sellar and Parasellar Regions

Endoscopic skull base surgery has become an integral part of the present neurosurgical armamentarium. The pioneering efforts in which the purely endoscopic transsphenoidal approach was introduced have triggered a growing tide of using the endoscopic endonasal procedures for a large variety of skull base lesions. Because of their anatomical peculiarities, lesions of the sellar and parasellar regions lend themselves very well to the endoscopic endonasal approaches. Apart from the common pathological entities, many other less frequent pathologies are encountered in the sellar and parasellar area. In this chapter, we review the surgical technique of the endoscopic endonasal transsphenoidal approach and its extensions applied to a variety of rare and uncommon pathological entities involving the sella turcica and clivus. An overview of these pathological entities is also presented and exemplified.

Differential Diagnosis in Hypophysitis: First Report on a Spindle Cell Rhabdomyosarcoma of the Pituitary Gland

Pituitary gland metastases are very rare. Most patients with pituitary gland metastases are asymptomatic; therefore, most cases of this disease are diagnosed during autopsies. Moreover, the four most common primary tumors that metastasize to the pituitary gland are breast, lung, thyroid, and renal carcinomas. We present a very rare case of pituitary metastasis of spindle cell rhabdomyosarcoma (RMS). Our patient presented with headache, visual disorder, panhypopituitarism, and diabetes insipidus. Due to tumor expansion, resection was not possible, so diagnosis was confirmed by biopsy, and chemotherapy and irradiation were administered. Our patient showed widespread spindle cell RMS, which harbors a mutation of myogenic differentiation 1 (MYOD1) and is associated with a poor prognosis. Even high-risk patients can show a remission after chemotherapy and irradiation. In the cases with indistinct lesions in the sella region, pituitary metastasis should always be considered.

Sarcomas of the sellar region: a systematic review

PURPOSE AND METHODS

Sarcomas of the sellar region are uncommon and unexpected tumors. Here, we review the cases reported in literature via a systematic search.

RESULTS

Ninety-four patients, 58.5% male with mean age of 39.2 ± 17.2 years were included. Fifty-seven (62%) had soft tissue sarcomas (STS) and 35 (38%) bone sarcomas (BS). Sarcoma was a primary tumor in 66%, developed after radiotherapy in 31.9% and 7.4% were metastatic. Median time between radiotherapy and sarcoma development was 10.5 (11) years. Main presentation symptoms were visual disorders (87.9%), headache (61.5%) and III cranial nerve palsy (24.1%). After surgery, sarcoma persisted or recurred in 82.3% and overall mortality reported was 44.6% with 6.5 (14) months of median survival. Tumor appeared earlier in BS compared to STS (34.4 ± 15.1 vs. 42.6 ± 17.6 years), p = 0.034 and complete tumor resection was achieved more often (41.3% vs. 4.4%), p =  < 0.001. Condrosarcoma and rhabdomyosarcoma were more frequent subtypes among primary tumors while fibrosarcoma was among post-radiation sarcomas. Tumor size was larger in radiation associated sarcomas (mean maximum diameter 46.3 ± 9.3 vs. 29.1 ± 8.0 mm, p = 0.004) and persistency/recurrence was similar in both groups (70.1 vs. 73.3%, p = 0.259).

CONCLUSION

Sarcomas appear as mass effect symptoms in the middle aged population, mainly as primary tumors, but one third is associated with radiotherapy. Surgery is commonly not curative, mortality rate is high and death ensues shortly after diagnosis.

Primary CNS Alveolar Rhabdomyosarcoma: Importance of Epigenetic and Transcriptomic Assays for Accurate Diagnosis

We present the case of a 22-year-old woman who developed increasing headaches, nausea, and vomiting. Imaging identified a 3 × 3 cm heterogeneously enhancing cystic mass in the posterior III ventricular/pineal region. Pathology review of the initial lesion revealed a highly malignant spindle cell neoplasm composed of round to mostly oval elongated cells with relatively small amounts of cytoplasm arranged in sheets and fascicles with focal storiform pattern. Whole genome methylation analysis through unsupervised clustering with data generated from other primary intracranial tumors and peripheral sarcomas was performed at the German Cancer Research Center (DKFZ) and classified the tumor with the group of alveolar rhabdomyosarcomas (ARMS). Further RNA sequencing revealed an in frame PAX3 (EX 7)-NCOA2 (EX12) fusion confirming the diagnosis. This is the first evidence of occurrence of PAX3-NCOA2 in primary CNS ARMS.

Endoscopic Resection of Clival Malignancies

Surgical management of clival lesions presents numerous therapeutic challenges because of the close proximity of surrounding critical structures. With a detailed understanding of the endoscopic endonasal approach and relevant considerations, appropriate lesions can be removed in a safe and minimally invasive manner. Use of this technique as a primary approach represents the standard of care for many lesions at leading skull base centers, although adjunct techniques may be necessary in extensive lesions and those with significant lateral extension.