Renal cell carcinoma presenting as a masseteric space mass

Renal Cell Carcinoma Space Mass

Presenting

TJ. Gal, MD, Marion B. Ridley, MD, John A. Arrington, and Carlos Muro-Cache, MD, PhD

(Editorial Comment: The authors have nicely presented and illustrated a highly unusual site of presentation of metastatic disease.)

Neoplastic lesions of the masseteric space are exceedingly rare. Renal cell carcinoma, however, is a lesion that is notorious for distant metastasis. Often these metastases are the first sign of an otherwise occult primary. We present an unusual case of clear cell carcinoma of the kidney metastatic to the masseteric space. The differential diagnosis of masseteric space masses and clear cell neoplasm, as well as the management of renal cell metastases to the head and neck, are presented. CASE REPORT A 49-year-old white male presented to the otolaryngology clinic with a 4- to 5-week history of right-sided facial swelling. He had no trismus and no history of trauma. The patient was an occasional cigar smoker and admitted to infrequent consumption of alcohol. Past medical history was otherwise unremarkable. Head and neck examination was significant for an approximately 4 X 4-cm mass in the area of the left parotid gland. Facial nerve function and the remainder of his examination

were normal. A computed tomography (CT) scan was obtained, revealing a mass in the left masseteric space (Fig 1). Subsequent magnetic resonance imaging (MRI) showed a lobulated well-delineated mass extending from the zygomatic arch to the mid portion of the ascending ramus of the mandible (Figs 2 and 3). The lesion did not appear to involve the mandible as evidenced by the sharp cortical margin of the bone on CT scan, and appeared to be

From the Division of Otolaryngology, Departments of Radiology and Pathology, University of South Florida College of Medicine, Tampa, FL. Address reprint requests to Marion B. Ridley, MD, University of South Florida College of Medicine, Division of Otolaryngology/Head and Neck Surgery, H. Lee Moffitt Cancer Center, 12902 Magnolia Dr, Tampa, FL 33612. Copyright 0 1997 by W.B. Saunders Company 0196-0709/97/l 804-0011$5.00/0 280

American

Journal

of Otolaryngology,

as a Masseteric

MD,

deep to and of higher signal intensity than the masseter muscle. Fine needle aspiration of the lesion performed on two occasions yielded definitive diagnosis. With a working diagnosis of intramuscular

no he-

mangioma, the lesion was excised through a preauricular incision. Intraoperatively, the mass was found to be deep to the masseteric fascia. The lesion was excised with clear margins. Final pathological diagnosis indicated clear cell carcinoma highly

suspicious for metastatic renal cell carcinoma. In retrospect, the preoperative urinalysis did show microscopic hematuria, 1 to 2 red blood cells per high-powered field, consistent with the diagnosis. With this information, an abdominal CT was performed, which showed a lesion at the upper pole of the left kidney as well as a right adrenal mass and enlargement of the left adrenal gland. The

patient underwent

a left radical nephrectomy

and

bilateral adrenalectomy. The left renal mass was found to be a clear cell renal carcinoma with metastases to both adrenals. The patient was found to have involvement of the pancreatic tail 2 years later and underwent distal pancreatectomy, splenectomy, and omentectomy. He then developed involvement and compression of his duodenum and died of complications from gastrointestinal hemorrhage, 3 years after the presentation of his masseteric mass. There was no evidence of residual disease in the head and neck.

DISCUSSION Renal cell carcinoma frequently presents with distant metastases. Often the metastatic lesion is the initial presentation of an otherwise occult primary. These lesions are not uncommonly found in the head and neck. Renal cell carcinoma is the third most common metastatic lesion of the head and neck (after lung and breast cancer) and is the most common metastatic lesion of the sinonasal tract. In a series by Boles and Cernyl of 105 patients with renal cell carcinoma over a 6-year period, 16 (15.2%) were found to have metastases to the head and neck, 8 of which (7.6%) presented initially with the head and neck lesion, The rich venous plexuses and

Vol 18, No 4 (July-August),

1997:

pp 280-282

RENAL

CELL

CARCINOMA

Fig 1. initial CT scan the right masseter muscle.

IN MASSETERIC

showing

mass

281

SPACE

lesion

deep

to

anastomoses of the vertebral and epidural systems are thought to explain the mechanism by which these tumors are able to bypass the pulmonary system and metastasize to the head and neck.2 Skeletal muscle is one of the most unusual sites of reported metastasis of renal cell carcinoma. Many of these lesions go undiagnosed because they are often asymptomatic, remaining hidden within large muscle mass. Autopsy series report the incidence of metastatic disease from any lesion to skeletal muscle to be within the range of 1% to 6%.3 Isolated meta-

Fig within

2. Tl-weighted image MRI the bed of the right masseter.

illustrating

the

mass

Fig 3. Tl-weighted coronal MRI again showing the lesion within the masseteric space. The mass appears distinct from the cortical margin of the mandible.

static lesions to skeletal muscle and to the musculature of the head and neck have been documented, specifically to the tongue.4 To our knowledge, however, there are no previous reports of metastatic lesions to the masseter muscle. The most common tumor of the masseter muscle is intramuscular hemangioma. Fifteen percent of these tumors are found in the head and neck, one third of which are localized to the masseter.5 Clear cell carcinoma originating in the masseter muscle has not been described. These tumors may arise from the intercalated ducts of the parotid gland, but account for less than 1% of the neoplasms of this gland. They are composed of columnar epithelial cells and ovoid cells with clear cytoplasm that stain positively for glycogen’j Clear cell carcinoma of odontogenie origin has also been described as involving the mandible and can be confused with bony metastasis of renal cell carcinoma.7 The differential diagnosis of clear cell carcinoma of the head and neck includes other tumors that may contain clear cells. These include acinic cell carcinoma, mucoepidermoid carcinoma, odontogenic clear cell carcinoma, metastatic renal cell carcinoma, and metastatic clear cell carcinoma of the thyroid. Histochemical and morphological analysis is useful in differentiating these lesions (Fig 4). The clear cytoplasm of the cells from all of the above lesions will stain positively for glyco-

Fig 4. membrane small cell nification

lmmunohistochemical antigen of masseteric clusters with vacuolated x 100).

staining for epithelial space mass. Note the nuclei (original mag-

gen, keratin, and vimentin. Clear cell renal cell carcinoma, however, will also stain positively for lipid, whereas clear cell carcinoma of the thyroid does not. Immunoperoxidase staining for thyroglobulin may be positive in those lesions. Renal cell carcinomas tend to form small, closely apposed clusters with minimal stroma. Extensive hemorrhage and formation of vascular lakes support the diagnosis. Renal cell carcinoma does not tend to have the acinar cell features of acinic cell neoplasms. Acinic cell carcinomas and mucoepidermoid carcinomas also contain mucin granules not found in renal cell carcinoma. The prognosis of patients with renal cell carcinoma is poor. The 5year survival of patients after treatment for primary renal cell carcinoma ranges from 60% to 75% without metastasis, but mean survival decreases to about 2 years once distant spread is discovered.8 Isolated reports have indicated that when only a single detectable metastasis in the nose or maxillary sinus is found after treatment for renal cell carcinoma, 5-year survival approaches 50%, with occasional longterm survivors.g Occasionally, the primary tumor can remain occult for long periods of time, sometimes presenting years after the appearance of metastatic disease. Metastatic renal cell carcinoma must always be included in the differential diagnosis of any clear cell neoplasm of the head and neck. Aggressive

GAL

ET AL

diagnostic work-up, including intravenous pyelogram and abdominal CT scanning, should be performed if suspicion exists. When the primary renal tumor is discovered concomitantly with the metastasis, nephrectomy is recommended in an attempt to improve prognosis.lO Radiation and chemotherapy have limited roles in the management of metastatic disease. SUMMARY We present an unusual case of renal cell carcinoma metastatic to the masseter muscle. Whereas metastasis of renal cell carcinoma to the head and neck in itself is common, metastasis to skeletal muscle is quite infrequent. Although the presence of metastasis in renal cell carcinoma implies an overall worse prognosis, surgical extirpation as well as management of the primary lesion is still advisable in the hope of achieving long-term survival. Renal cell carcinoma metastasis must always be included in the differential diagnosis of clear cell neoplasms of the head and neck. REFERENCES 1. Boles R, Cerny J: Head and neck metastases from renal cell carcinoma. Mich Med 70:616-618, 1971 2. Batsakis JG: Tumors of the Head and Neck (ed 2). Baltimore, MD, Williams &Wilkins, 1979, p 243 3. Munk PL, Gock S, Gee R, et al: Case report 708: Metastatis of renal cell carcinoma to skeletal muscle (right trapezius). Skeletal Radio1 21:56-59,1992 4. Okabe Y, Ohoka H, Miwa T, et al: Renal cell carcinoma metastasis to the tongue. J Laryngol Otol 106:282284,1992 5. Wolf GT, Daniel F, Krause CJ: Intramuscular hemangioma of the head and neck. Laryngoscope 2:210-213, 1985 6. Batsakis JG, Kraemer B, Sciubba JJ: The pathology of head and neck tumors: The myoepithelial cell and its participation in salivary gland neoplasia, Part 17. Head Neck 5:222-233, 1983 7. Eversole LR, Duffey DC, Powell NB: Clear cell odontogenic carcinoma. Arch Otolarvngol Head Neck Surg . 12>:685-689,1995 8. Matsumoto Y. Yaneihara N: Renal clear cell carcinoma metastatic tothe n&e and paranasal sinuses. Larvngoscope 92:1190-1193,1992 9. Bernstein TM, Montaomerv WW, Balogh HK: Metastatic tumors to the maxilla, nose and paranasal sinuses. Larygoscope 87:621-650,1987 10. Hefer T, Joachims HZ, Golz A: Metastatic renal cell carcinoma to the nose. Eur Arch Otorhinolaryngol251:127129,1994