Carcinoma of the salivary gland is an uncommon disease, accounting for less than 1% of all head and neck malignant neoplasm.1 Lymphoepthelioma is a malignant tumor of epithelial origin showing varying amounts of reactive lymphocytic infiltrate. Lymphoepithelioma-like carcinoma (LELC) consti- tutes a significant proportion of salivary gland carcinoma in Chinese and Eskimo populations and is related to Epstein-Barr virus infection.2,3 Carcinoma of the salivary gland has a propensity for early lymphatic metastasis, and thus a swelling of cervical lymph nodes is occasionally the sole initial symptom. It is very vital to consider a multimodality approach including surgery, radiotherapy and chemotherapy for the treatment in the locally advanced disease.
A 29-year-old woman presented with a history of a mass in right mandible region for more than 1 year without pain, fever, or other symptoms. The contralateral gland was normal. When the mass became increasingly large and firm, she presented to our hospital. Physical examination revealed a firm, mobile and indolent submandibular gland mass, measuring 2.5 cm in diameter. Serum Epstein-Barr virus antibody was negative. Upon excision of right submandibular gland and mass, pathology confirmed diagnosis of LELC of salivary gland, with 2 lymph node metastasis (2+/2). The neoplasm consisted of tumor cells with round and prominent nucleoli. The cell margins were indistinct and the tumor exhibited a syncytial appearance with a marked lymphocytic infiltrate (Fig. 1). The tumor cells expressed cytokeratins (Fig. 2) and were negative for the lymphoid marker (Fig. 3). TNM staging was T2N2bM0 (stage IVA). Fifteen days after her initial excision, she underwent expanded dissection of the right submaxillary triangle and right modified selective neck dissection. Resection of 53 additional lymph nodes revealed no further metastatic cancer. The patient was treated with chemotherapy, which consisting of cisplatin (30 mg/m2, days 1 to 3) and 5-fluorouracil (500 mg/m2, days 1 to 5) every 3 weeks for 2 cycles. She then underwent irradiation to the primary site and upper neck fields to a total dose of 50 Gy at 2 Gy per fraction once a day. Four additional courses of chemotherapy followed the course of radiotherapy, with the same regimen. The patient was alive without recurrence or distant metastasis 16 months after the treatment.
Histologically and immunophenotypically identical tumors arising outside the nasopharynx are designated LELCs,4 and have been described in the gastrointestinal tract, lung, salivary glands, thymus, the skin, larynx, thyroid, uterine cervix, prostate, and urinary tract. Indeed, LELCs are characterized by either cohesive nests or by a diffuse growth of malignant epithelial cells in a background of inflammatory cells that are predominantly lymphocytes.5
The cases of LELCs have been conventionally classified as being ‘high grade' because of their poor histological differentiation. The mainstay of treatment is surgical resection. Despite their poor differentiation and high histological grade, LELCs are very radiosensitive and bear a better prognosis than the other high-grade salivary gland tumors such that radiotherapy has been used instead of surgery as the primary treatment of LELC in some cases.6
Prognosis in this disease depends on the stage7 and grade8,9 of the cancer, the completeness of surgical resection, and when the resection is incomplete, whether or not postoperative radiotherapy is administered.8,10-12
The team of Parsons et al7 and Teo et al13 showed that the best local control was achieved by the combined approach of performing radical resection and then giving radiotherapy. The appearance of LELCs, its clinical course, and behavior were benign in their studies. Postoperative radiotherapy is indicated when the resection margin is positive or close,8 the tumor is high grade,8 there is tumor infiltration of adjacent organs, or regional metastasis is extensive.7 Our patient had 2 regional lymph nodes metastasis for a stage of T2N2bM0, so after operation, we gave her 1 course of radiotherapy and 6 cycles of chemotherapy.
LELC in the salivary gland drains primarily to the ipsilateral neck nodes. In contrast, nasopharyngeal carcinoma arises from a midline organ having significant bilateral cervical lymphatic drainage, thus resulting in the frequent occurrence of bilateral nodal disease. Elective radiotherapy to the clinically at-risk neck nodes is indicated for LELC of the head and neck. LELC has been generally considered to be very radiosensitive, and a significant number of gross tumors have been permanently controlled by a radiation dose of 60 Gy.6 It would appear that a dose of at least 50 Gy would be necessary to achieve adequate local control after surgical resection.
Hsiung et al14 treated 9 patients with LELC of salivary glands from June 1987 to May 2001. One patient was excluded due to the loss of clinical follow-up after surgery. In the remaining 8 patients, the primary tumor sites were parotid gland (4 patients), submandibular gland (3), and buccal minor salivary gland (1). Seven patients underwent surgical treatment and post-operative radiotherapy, while 1 patient was treated with surgery alone. The survival time ranged from 21.4 months to 145.2 months (mean: 69.1 months, median: 54.5 months). At the end of follow-up, 6 patients were still alive and 2 died. One patient (left submandibular gland, T3N2b) died of distant metastases 21.5 months after the surgical treatment of LELC. The other case (right submandibular gland, T3N0M0) died of intercurrent disease (pontine haemorrhage) 53 months after surgery. No patient suffered local or regional failure after the treatment. Distant failure was noted in 2 patients (left parotid gland T3N2bM0, left submandibular gland, T3N2b) and received chemotherapy with CDDP and 5-fluorouracil. No local or regional failure was noted. The authors advised careful monitoring for distant metastases, especially in patients with more advanced neck node involvement. To address the risk of distant metastases, we treated our patient with 6 cycles of chemotherapy.
Cases of relapse may be successfully salvaged by further treatments such as the second operation and radiotherapy. However, it is advisable to carefully treat newly diagnosed patients adjuvantly, as this yields a good prognosis.
Acknowledgement: We would like to thank Dr. Case H. Ketting, M.D. (San Jude Hospital, California, USA) for his polishing the English writing of the article.
1. Spitz MR, Batsakis JG. Major salivary gland carcinoma. Descriptive epidemiology and survival of 498 patients. Arch Otolaryngol 1984;110:45-49.
2. Leung SY, Chung LP, Yuen ST, Ho CM, Wong MP, Chan SY. Lymphoepithelial carcinoma of the salivary gland: in situ detection of Epstein-Barr virus. J Clin Pathol 1995;48:1022-1027.
3. Saw D, Lau WH, Ho JH, Chan JK, Ng CS. Malignant lymphoepithelial lesion of the salivary gland. Hum Pathol 1986;17:914-923.
4. Gillum PS, Morgan MB, Naylor MF, Everett MA. Absence of Epstein-Barr virus in lymphoepitheliomalike carcinoma of the skin: Polymerase chain reaction evidence and review of five cases. Am J Dermatopathol 1996;18: 478-482.
5. Cristina S, Boldorini R, Brustia F, Monga G. Lymphoepithelioma-like carcinoma of the breast. An unusual pattern of infiltrating lobular carcinoma. Virchows Arch 2000;437:198-202.
6. Dubey P, Ha CS, Ang KK, El-Naggar AK, Knapp C, Byers RM, et al. Non-nasopharyngeal lymphoepithelioma of the head and neck. Cancer 1998;82:1556-1562.
7. Parsons JT, Mendenhall WM, Stringer SP, Cassisi NJ, Million RR. Management of minor salivary gland carcinomas. Int J Radiat Oncol Biol Phys 1996;35: 443-454.
8. Spiro RH. Management of malignant tumours of the salivary glands. Oncology (Williston Park) 1998;12: 671-680.
9. Rodrguez-Cuevas S, Labastida S, Baena L, Gallegos F. Risk of nodal metastases from malignant salivary gland tumours related to tumour size and grade of malignancy. Eur Arch Otorhinolaryngol 1995;252:139-142.
10. Rafla S. Salivary glands. In: Halnan KE, eds. Treatment of cancer. London: Chapman and Hall;1982:269-294.
11. Sessions RB, Harrison LB, Hong WK. Tumors of the salivary glands and paragangliomas. In: DeViat VT Jr, Steven SH, Rosenberg JB, eds. Cancer principles and practice of oncology. 4th ed. Philadelphia: JB Lippincott Company; 1993:655-672.
12. Napier SS, Herron BT, Herron BM. Acinic cell carcinoma in Northern Ireland: a 10-year review. Br J Oral Maxillofac Surg 1995;33:145-148.
13. Teo PM, Chan AT, Lee WY, Leung SF, Chan ES, Mok CO. Failure patterns and factors affecting prognosis of salivary gland carcinoma: retrospective study. Hong Kong Med J 2000;6:29-36.
14. Hsiung CY, Huang CC, Wang CJ, Huang EY, Huang HY. Lymphoepithelioma-like carcinoma of salivary glands: treatment results and failure patterns. Br J Radiol 2006;79:52-55.