A 52-year-old man complained of nasal stuffiness along with bleeding, headache, and vomiting. He was referred to our department after magnetic resonance imaging (MRI) showed an enormous mass occupying the nasal and paranasal cavities and extending into the bilateral frontal base [Figure and ]. No neurological deficit other than anosmia was identified. The tumor spread beyond the nasal cavity and paranasal sinuses, and was therefore classified as stage C based on the modified Kadish clinical staging system [].[] Total removal of the tumor was achieved surgically, using a transnasal approach in combination with a bilateral front basal craniotomy [Figure and ]. The dura along the anterior skull base was opened partially and the cranial base was reconstructed using the pericranial flap. Histological examination of the tumor demonstrated proliferating tumor cells with large, oval nuclei containing prominent nucleoli. Scattered necrotic changes, nuclear fission, and Homer–Wright rosettes were identified. These findings were consistent with Hyams grade III ONB [].[] No neurological deficit other than olfactory analgesia was observed after surgery, however, the patient suffered from meningitis caused by cerebrospinal fluid rhinorrhea that developed 1 week postoperatively. Because complete eradication of the rhinorrhea and meningitis required 9 weeks of treatment, radiation therapy was started 10 weeks after the surgery. Large-field irradiation of the resected area, from the nasal cavity to the frontal lobe, was administered with a total of 60 Gy in 30 fractions. The patient was discharged 17 weeks after the surgery and was followed-up on an outpatient basis. At the time of discharge, whole-body enhanced computed tomography (CT) revealed no apparent distal metastasis or tumor recurrence.\nAt 24 weeks postoperatively, the patient noted numbness in both upper limbs, which gradually worsened. He was readmitted 25 weeks after the surgery because of rapidly deteriorating symptoms. Neurological findings on readmission revealed tetraparesis, hypesthesia, and hypoalgesia below C6, hyperreflexia of both legs, and urinary incontinence. CT and MRI revealed an intradural lesion compressing the spinal cord along its right ventral aspect at C5 through T2 [Figure –]; MRI of the head showed no evidence of tumor recurrence. In view of the diffuse nature of the disease, it was decided to surgically relieve the compression by the tumor to avoid complete tetraplegia. A laminectomy from C4 to T3 was performed. Intraoperative findings confirmed the absence of tumor in the epidural space. However, under the arachnoid membrane, the tumor compressed the spinal cord along its right ventral aspect. Because the tumor adhered to the spinal surface and was entangled in several nerve roots, it was removed but not completely. A dural plasty was then performed with a Gore-Tex® membrane to avoid restriction of the subdural space. The tumor was histologically diagnosed as ONB, consistent with the first operation [Figure and ]. After surgery, his urinary incontinence promptly improved. Paralysis of the right upper and both lower limbs remained but seemed to be improving. Residual tumor was seen on MRI performed 1 week after the surgery but the spinal cord was well decompressed [Figure –]. Whole-spine irradiation of 58 Gy in 29-Gy fractions was started 1 week postoperatively. MRI after irradiation no longer revealed residual spinal tumor, but shortly after spinal irradiation, the patient became progressively lethargic. Brain MRI showed multiple leptomeningeal enhanced lesions. General malaise and anorexia followed and the patient developed bilateral pneumonia, which caused his death 16 weeks after the surgery for ISM and 41 weeks after the first operation. During the time before his death, there had been no further deterioration in the motor weakness of his four extremities.
A 48-year-old woman presented with a large sinonasal mass with extensive intracranial extension through the cribriform plate into the anterior cranial fossa []. Tumor was noted in the right orbit and maxillary and sphenoid sinuses and there was lymphatic spread to a retropharyngeal lymph node. She underwent radical resection of the Kadish stage D esthesioneuroblastoma with a right orbital exenteration and upper neck dissection followed by adjuvant radiation therapy. Yearly surveillance imaging was stable until a 6-year follow-up MRI revealed 1 cm of patchy enhancement in the right frontal lobe and the dura overlying the resection cavity. Follow-up imaging 6 months later showed mildly increased dural enhancement and interval development of a new dural-based lesion in the posterior fossa.\nSpinal imaging revealed multiple dural-based enhancing lesions in the cervical, thoracic, and lumbar spine with possible osseous involvement, consistent with drop metastasis []. The patient underwent a suboccipital craniectomy for resection of the posterior fossa lesion. Intraoperatively, the neoplasm was deep to the dura but above the arachnoid membrane; it was carefully dissected and removed en bloc. Two days later, the patient underwent T8–T10 laminectomies, left T9 costotransversectomy, and ligation of the nerve root for resection of a large dural-based mass displacing the thoracic cord and effacing the neural foramen. Pathological analysis of both lesions affirmed a diagnosis of recurrent esthesioneuroblastoma with leptomeningeal spread [].\nThe patient initially began a course of systemic carboplatin, vincristine, and lomustine, as well as intrathecal methotrexate. She ultimately completed the intrathecal methotrexate with carboplatin, etoposide, and cyclophosphamide. Follow-up imaging 16 months after the initiation of chemotherapy revealed resolution of the metastatic lesions and no radiographic appearance of residual disease, 9 years after her original diagnosis. She continues to receive surveillance for the recurrent disease by evaluation of her cerebrospinal fluid (CSF) every 3 months.