Aggressive papillary tumors of the temporal bone: an immunohistochemical analysis in tissue culture

Papillary tumor of the temporal bone

Papillary tumors of the middle and inner ear have been interpreted histogenetically in many ways. In 1989 Heffner proposed the endolymphatic sac epithelium as a possible origin. These rare tumors are clinically aggressive and can cause extensive temporal bone destruction. Because of this behavior, endolymphatic sac tumors (ELST) were classified as low-grade adenocarcinomas, although metastasis has not yet been documented. Two papillary neoplasms of the temporal bone are presented, which we believe are examples of adenomatous tumors arising from the epithelium of the endolymphatic sac. One was associated with a pituitary adenoma. A third case of a papillary middle ear neoplasm is described that shows histologic features similar to the other two, but it was located in the tympanum and had no connection to the endolymphatic sac. This report focuses on clinical, radiologic, and histologic findings of papillary tumors of the temporal bone with additional emphasis on modern concepts of histogenesis and aspects of differential diagnosis.

Cochlear implantation in a bilateral endolymphatic sac tumor patient. A case report

At the present time, the optimal management of patients with locally aggressive ELSTs includes: early diagnosis, surgical complete excision and long term follow up to monitor for recurrent disease. The presence of bilateral tumors produces a significant risk for bilateral profound hearing loss. We report the unusual case of bilateral endolymphatic sac tumor in a 14-year-old girl who presented bilateral anacusis and in whom a cochlear implant was performed after removal of the second tumor.

Endolymphatic sac tumor in a 4-year-old boy

INTRODUCTION

Endolymphatic sac tumors (ELST) are rare, low-grade, locally aggressive papillary neoplasms. We present a case of a 4-year-old boy with an ELST, the youngest described in the literature.

CASE

A boy presented with a right-sided serous otitis media and sudden-onset right facial nerve palsy. An audiogram revealed right-sided profound sensorineural hearing loss. Radiographic imaging demonstrated a 3-cm expansile lytic lesion along the posterior face of the petrous bone.

INTERVENTION/RESULTS

The patient initially underwent a right transmastoid-infralabyrinthine biopsy. Pathologic examination revealed a papillary lesion suspicious for an ELST. Subsequently, a transtemporal-transcochlear approach with intra-and extradural resection of the tumor was performed. The facial nerve was dissected and transposed anteriorly and preserved. Histopathologic and immunohistochemical studies confirmed the ELST. At his 6-month follow up, there is no evidence of recurrence and the facial nerve function has returned to Grade II palsy.

CONCLUSION

ELST are rare tumors of the temporal bone. This is the youngest case of ELST reported. Presentation, evaluation, and management of ELST is discussed.

Endolymphatic sac tumor (low-grade papillary adenocarcinoma) of the temporal bone

The entity which has come to be known as an endolymphatic sac tumor (ELST) has, in the past, been known as adenocarcinoma of endolymphatic sac origin, aggressive papillary tumor of the temporal bone and Heffner's tumor. ELSTs arise in the vicinity of the inner ear and may extend to involve both the posterior fossa as well as the middle ear and the external ear canal, which may complicate the differential diagnosis ELSTs are typically seen in adults, with only rare descriptions in pediatric patients. They may be sporadic tumors or they may arise as part of the symptom complex of von Hippel-Lindau disease. Clinical signs at presentation range from a mass in the external ear canal to sensorineural deafness to cranial nerve palsies. Imaging studies reveal a destructive lesion of the petrous bone which is heterogeneous on MR scanning. Light microscopy reveals two chief patterns: a follicular pattern, reminiscent of thyroid parenchyma; and a papillary/solid pattern. Both patterns are often admixed in the same tumor, and the individual tumor cells are cytologically bland. Immunohistochemically, ELSTs are typically keratin-, vimentin- and epithelial membrane antigen-positive; they are often S-100 protein-positive and neuron-specific enolase-positive as well. ELSTs are difficult to extirpate surgically (owing to their locally aggressive nature); nevertheless, surgical excision remains the mainstay of current therapy. These are slow-growing (albeit locally aggressive) tumors which have only rarely been reported to metastasize; as such, they remain principally a problem of local control.

Stereotactic radiosurgery for aggressive papillary tumor of the temporal bone: case report

BACKGROUND

Papillary tumors of the temporal bone are very rare neoplasms that show locally aggressive behavior though they have low-grade histologic features. The best treatment for these tumors is a radical resection. However, if the tumor is very large, local invasiveness and hypervascularity can prevent surgeons from achieving a complete resection. As an additional treatment for the residual tumor, it remains controversial whether radiation therapy has any role.

CASE DESCRIPTION

The authors describe a 53-year-old woman who suffered from left-sided tinnitus, hearing loss, and diplopia due to a large aggressive papillary tumor of the temporal bone. Radiosurgery was very effective for the tumor, which had regrown a few years after conventional radiation therapy and chemotherapy.

CONCLUSIONS

The authors conclude that radiosurgery should be considered as an option for the treatment of aggressive papillary tumor of the temporal bone.

Endolymphatic sac tumor associated with a von Hippel-Lindau disease patient: an immunohistochemical study

The authors report a case of endolymphatic sac tumor (ELST) associated with Von Hippel-Lindau disease (VHL). A 20-year-old female VHL patient received a resection of a cerebellar hemangioblastoma 3 years ago and she had a co-existing of left petrous tumor. The petrous tumor showed a remarkable progression in 3 years and was resected subtotally. Histologically, the resected petrous tumor showed a papillary structure containing cuboidal or columnar cells with fibrous stroma and numerous microvessels and destructed temporal bone, all of which are consistent with ELST. We studied the expression of various kinds of cytokeratins (CKs) immunohistochemically and found distinct expression of CKs (CAM 5.2, 34betaE-12, CK7, CK8 and CK19), but not for CK10/13 or CK20. Vascular endothelial growth factor and neuron specific enolase showed strong immunoreactivity in the tumor cells. CD34 also had weak expression. Ki-67 antigen (MIB-1) immunoreactivity was found in focal areas, and the labeling index in the highest-density area was 48.9%. These findings suggest that vascular endothelial growth factor overexpression is an important factor for angiogenesis in ELST, much like other VHL-associated tumors, and that ELST may have a more highly aggressive component than the low-grade malignancy noted in previous reports.

Endolymphatic sac tumours

This review article surveys clinical and pathological literature on endolymphatic sac tumours (ELST) and summarizes characteristics that describe the entity. ELST are rare neuroectodermal neoplasms in the petrous bone, originating from inner ear structures. They can be encountered sporadically or in von Hippel-Lindau disease. The most prominent symptom is sensorineural deafness. Historically, nomenclature of invasive adenoid tumours in the petrous bone has been divergent, the term papillary adenocarcinoma used most frequently. Histologically, they have a follicular or papillary and adenoid pattern that can be easily confused with various other neoplastic conditions including metastatic carcinoma. It remains to be verified whether similar tumours (papillary adenocarcinomas) can originate from the middle ear. Middle ear adenomas have a similar appearance but probably originate from neural crest cells in the middle ear. ELST can express a variety of epitopes (including cytokeratin and neuroectodermal markers) which can be detected immunohistochemically. In cases in von Hippel-Lindau disease the cerebello-pontine angle should be included in routine radiological examinations to detect ELST before the tumours lead to deafness. In apparently sporadic cases of ELST, genetic testing for von Hippel-Lindau disease should be considered. Correct distinction of ELST from metastatic carcinoma prevents futile searches for unknown primary tumours.