Blindness: a sequela of sinonasal small cell neuroendocrine carcinoma.

A 44-year-old man presented to the emergency room with a 2-day history of headache and blindness in his right eye. He also reported a 2-week history of nasal congestion, rhinorrhea, and recurrent epistaxis. On physical examination, his visual acuity was 20/40 in the left eye, but he had only light perception in the right eye. Nasopharyngoscopy detected bilateral mucoid discharge and a large friable mass, which obstructed the right nasal cavity. Bilateral level I, firm, fixed, 3 x 3-cm neck masses and multiple bilateral fixed nodes were present in the anterior and posterior triangles, and they extended into the supraclavicular fossa bilaterally.

Magnetic resonance imaging (MRI) revealed that a 5.2 x 3.0 x 6.8-cm soft-tissue mass involved the right nasal fossa with deviation of the septum and extension into the left nasal cavity (figure 1). The tumor extended into the right ethmoid, sphenoid, and frontal sinuses, the right medial orbital wall, and the orbital apex. Intracranial extension into the right anterior cranial fossa was also evident.

[FIGURE 1 OMITTED]

The patient underwent a nasopharyngeal biopsy and an excisional biopsy of a right level V lymph node. Histopathologic examination of both specimens identified a small round cell malignant neoplasm with a uniform, monotonous population of small blue round cells and effacement of normal architecture (figure 2). Apoptosis, numerous mitoses, and occasional molding were present. Areas of necrosis were not identified. Immunohistochemical studies were positive for synaptophysin and CD56 (NCAM), chromogranin A, epithelial antigen, and CAM 5.2/AE-1. The histopathologic diagnosis was small cell neuroendocrine carcinoma. The patient was referred for radiation therapy and adjuvant chemotherapy with cisplatin and etoposide.

[FIGURE 2 OMITTED]

Only 4% of small cell neuroendocrine carcinomas arise in extrapulmonary sites. (1) In the head and neck, the most common site is the larynx. Small cell neuroendocrine carcinoma of the sinonasal region is rare. Immunohistochemical studies are important for confirming small cell neuroendocrine carcinoma and for ruling out other malignancies because these tumors cannot be diagnosed by histology alone. In the case described here, histopathologic examination identified a small round cell malignancy pending its categorization by immunohistochemistry. The differential diagnosis included lymphoma, rhabdomyosarcoma, undifferentiated nasopharyngeal carcinoma, undifferentiated sinonasal carcinoma, and small cell carcinoma. Immunohistochemical findings included positive staining with synaptophysin and CD56 (NCAM) and weak staining with chromogranin A and CAM 5.2/AE-1. These findings confirmed small cell neuroendocrine carcinoma.

The prognosis for patients with extrapulmonary small cell carcinoma is poor, as 5-year survival is only 13%. (2) A mere 28 cases of sinonasal small cell carcinoma have been reported in the English-language literature to date. (1-7)

References

(1.) Galanis E, Frytak S, Lloyd RV. Extrapulmonary small cell carcinoma. Cancer 1997;79:1729-36.

(2.) Raychowdhuri RN. Oat-cell carcinoma and paranasal sinuses. J Laryugol Otol 1965;79:253-5.

(3.) Perez-Ordonez B, Caruana SM, Huvos AG, Shah JP. Small cell neuroendocrine carcinoma of the nasal cavity and paranasal sinuses. Hum Pathol 1998;29:826-32.

(4). Mills SE, Fechner RE. "Undifferentiated" neoplasms of the sinonasal region: Differential diagnosis based on clinical, light microscopic, immunohistochemical, and ultrastructural features. Semin Diagn Pathol 1989;6:316-28.

(5.) Rejowski JE, Campanella RS, Block LJ. Small cell carcinoma of the nose and paranasal sinuses. Otolaryngol Head Neck Surg 1982;90: 516-17.

(6.) Chaudhry MR, Akhtar S, Kim DS. Neuroendocrine carcinoma of the ethmoid sinus. Eur Arch Otorhinolaryngol 1994;251:461-3.

(7.) Weiss MD, deFries HO, Taxy JB, Braine H. Primary small cell carcinoma of the paranasal sinuses. Arch Otolaryngol 1983;109: 341-3.