Management of salivary gland malignancies: current and developing therapies

Primary Lymphoepithelial Carcinoma of the Submandibular Gland in A Young Patient: A Case Report

Lymphoepithelial carcinoma (LEC) is a rare entity of malignancy. It has been associated with Epstein-Barr virus (EBV), and in regions where it is endemic, such as Southeast Asia, EBV is typically associated with nasopharyngeal carcinoma. The incidence of such malignancies in the young population is unusual. Here we report a 17-year-old with a 5-year history of a painless right submandibular mass presenting with a sudden increase in size for one month before surgery. Neck examination revealed a firm right submandibular gland measuring five by five cm, with an irregular surface, non-tender with normal overlying skin. We performed a fine needle aspiration cytology (FNAC), and he underwent computed tomography (CT) scan of the neck. He underwent a right submandibulectomy. Lymph nodes from levels I and II were also removed. The final histopathology was reported as LEC. Following this tissue diagnosis, another follow-up surgery, a modified radical neck dissection, was carried out for locoregional clearance. Postoperatively, he completed chemoradiotherapy treatment and is now on regular follow-up.

Carcinoma ex Pleomorphic Adenoma in the Floor of the Mouth: An Unusual Diagnosis in a Rare Location

Carcinoma ex pleomorphic adenoma (CXPA) is a rare malignant salivary gland tumor, mostly involving the parotid and submandibular glands. Minor salivary gland involvement is even rarer, palate being the most common site. Other reported sites are upper lip, sinonasal tract, and buccal mucosa. Here, we report a case of CXPA in an unusual location, the floor of the mouth.

Case Report: Recurrent Mucoepidermoid Carcinoma of the Tongue in Adult Female Patient With Lung Cancer

There is a steady rise in incidence of malignant salivary gland tumors in the United States, with mucoepidermoid carcinoma (MEC) the most frequent. Although 40% of MECs are found in the parotid gland, these lesions possess the capacity to develop anywhere along the aerodigestive tract. Here, we present a case of recurrent tongue MEC in a young adult female patient with history of lung malignancy and multiple brain metastases. Without a universally accepted management protocol for recurrent MECs, the current clinical practice uses tumor grade, location, and clinical progression to determine both prognosis and goals of care. The patient had transoral laser excision of the first MEC lesion in 2013. Her tongue MEC recurred 3 years later with 2 distinct lesions. One was discovered on physical examination and computed tomography and the other diagnosed intraoperatively 1 month later. These lesions were located on a previously unaffected portion of dorsal tongue base. These lesions were completely excised in the operating room. The patient currently remains on chemotherapy. This underscores the importance for developing a guideline that delineates the most efficacious surveillance and treatment plans for recurrent MECs.

Results of surgery plus postoperative radiotherapy for patients with malignant parotid tumor

PURPOSE

The latest version of the World Health Organization (WHO) histologic classification of salivary gland malignancies was published in 2005. To contribute to data accumulation on the basis of this latest version, a retrospective study was performed.

MATERIALS AND METHODS

Participants comprised 27 patients who underwent postoperative radiotherapy between 2000 and 2013. Two, eight, and 17 patients were allocated to low, intermediate, and high-grade groups, respectively, in accordance with the latest WHO classification. The radiation field included the tumor bed and ipsilateral regional lymph nodes for 25 patients. The radiation dose was 46-60 Gy (median 56 Gy).

RESULTS

Median duration of follow-up was 41 months. Five-year locoregional control was 89 %. Two patients experienced local recurrence and 7 patients developed distant metastases. No patients in the low or intermediate-grade groups developed distant metastases. Overall 3 and 5-year survival for all patients were 81 and 75 %, respectively. Five-year overall survival for patients in the low and intermediate-grade groups was 100 %, compared with 59 % for patients in the high-grade group (p = 0.03).

CONCLUSION

Favorable locoregional control was achieved for patients with malignant parotid tumors who underwent surgery plus postoperative radiotherapy. Patients with high-grade tumors frequently experienced distant metastases and prognosis was poor.

Primary lymphoepithelioma-like carcinoma of salivary gland: sixty-nine cases with long-term follow-up

BACKGROUND

Lymphoepithelioma-like carcinoma (LELC) in the salivary glands is a rare but unique malignancy.

METHODS

Sixty-nine patients with salivary gland LELC with long-term follow-up were reviewed for this study.

RESULTS

There were 52 cases in the parotid gland and 17 cases in the submandibular gland. All patients underwent complete tumor excision, 41 underwent neck dissection, and 39 received postoperative radiotherapy. The 5-year, 10-year, and 15-year overall survival (OS) rates were 90%, 75%, and 54%, respectively. Patients with higher neutrophil/lymphocyte ratio (NLR ≥ 4.0) and advanced stage (stage III and IV) had significantly poorer OS. Patients who received postoperative radiotherapy had significantly better relapse-free survival (RFS). In multivariate analysis, stage, NLR, and neck dissection were associated independently with OS, whereas stage and postoperative radiotherapy were associated independently with RFS.

CONCLUSION

Salivary gland LELC is a rare malignancy with a better prognosis that partially attributes to surgery with neck dissection and postoperative radiotherapy. Preoperative NLR is an independent prognostic factor.

Review of salivary gland neoplasms

Salivary gland tumours most often present as painless enlarging masses. Most are located in the parotid glands and most are benign. The principal hurdle in their management lies in the difficulty in distinguishing benign from malignant tumours. Investigations such as fine needle aspiration cytology and MRI scans provide some useful information, but most cases will require surgical excision as a means of coming to a definitive diagnosis. Benign tumours and early low-grade malignancies can be adequately treated with surgery alone, while more advanced and high-grade tumours with regional lymph node metastasis will require postoperative radiotherapy. The role of chemotherapy remains largely palliative. This paper highlights some of the more important aspects in the management of salivary gland tumours.