Neutron radiotherapy for recurrent pleomorphic adenomas of major salivary glands.

INTRODUCTION: Pleomorphic adenoma is the most common neoplasm arising in the salivary glands. Surgical management is the primary therapeutic modality. With the use of modern surgical techniques, recurrence is infrequent, and facial nerve sparing is the norm. However, for patients with recurrent disease, the risk of further relapses is increased with surgical resection alone, particularly for those patients in whom multiple recurrences have already occurred. The role of adjuvant radiotherapy in this setting remains uncertain. Although neutron radiotherapy is superior to conventional radiotherapy for malignant salivary gland tumors, its role in the treatment of pleomorphic adenomas is less well defined. We report our experience using this modality for high-risk, recurrent pleomorphic adenomas. METHODS: Sixteen patients were treated with neutron radiotherapy for recurrent pleomorphic adenomas of major salivary glands from 1986 through 1993. The median age at diagnosis was 33 years (range, 11-77 years); median age at the time of neutron radiotherapy was 52 years (range, 22-77 years); median number of prior surgical procedures was 3 (range, 1-6); median duration from initial diagnosis to radiotherapy was 14.5 years (range, 3 months-30 years); median follow-up was 83 months (range, 9-144 months). The median period at risk for survivors was 96 months (defined as the interval from completion of neutron radiotherapy to last follow-up). Ten patients had evidence of gross residual disease at the time of treatment as determined by imaging studies, with nine patients having multinodular disease. RESULTS: The 10-year actuarial survival was 79%. One patient died from lung metastases 9 months after treatment; one patient died from a liver tumor of uncertain origin, but the histology could not rule out a metastasis from the previous pleomorphic adenoma; and one patient died from recurrent disease at the base of skull. The 15-year actuarial locoregional control rate was 85%. One of the two patients with locoregional recurrence had a malignant transformation into an adenocarcinoma. No statistical difference in 15-year actuarial survival (75% vs 83%, p =.82) was found comparing patients with gross residual disease vs microscopic residual disease. The actuarial 15-year locoregional control was 76% for patients with gross residual disease vs 100% for those with microscopic disease. The 15-year actuarial risk of RTOG/ESTRO nonaudiologic grade III/IV complications was 21%. No facial nerve injuries were observed as a direct consequence of neutron radiotherapy. CONCLUSIONS: Neutron radiotherapy offers both excellent local control rates and survival rates in patients with multiply recurrent pleomorphic adenomas that are not candidates for surgical resection, even in the presence of gross residual disease. The treatment-related morbidity is acceptable. Malignant transformations and metastases, although uncommon, may be observed in this tumor.     

Synchronous benign and malignant salivary gland tumors in ipsilateral glands: a report of two cases and a review of literature

BACKGROUND: Ipsilateral salivary gland tumors of different histologic types are rare and make up less than 0.3% of all salivary gland neoplasms. Only nine cases of synchronous benign and malignant ipsilateral parotid gland tumors have been described in the literature. METHODS: Two additional cases of synchronous benign and malignant neoplasms in the parotid gland are reported and discussed with a review of literature. RESULTS: Our first case describes a pleomorphic adenoma and a salivary duct carcinoma, an entity not previously reported in the literature. The second case documents the most common benign and malignant ipsilateral parotid gland neoplasm reported in this case series, a Warthin's tumor and a mucoepidermoid carcinoma. CONCLUSIONS: Synchronous salivary gland tumors exhibiting both benign and malignant components are uncommonly observed, with only nine cases published to date. We describe two additional cases of a synchronous benign and malignant ipsilateral parotid gland tumor.     

Metastatic-adenoid cystic carcinoma of the major salivary glands presenting as a spinal cord tumor

An adenoid cystic carcinoma (cylindroma) of the sub-mandibular salivary gland presented 17 years after diagnosis with a compressive syndrome of the spinal cord as well as a local recurrence. This is the first reported case of such an occurence. The literature is reviewed concerning other malignant tumors of the salivary glands presenting in this way. Fifteen cases of mixed salivary-gland tumors are reviewed. Evidence of histologic change from one tumor type to another and the mechanism of spread to the vertebral column is discussed.     

Salivary gland disease in the era of COVID‐19 pandemic

Coronavirus disease 2019 (COVID‐19) pandemic forced significant changes in current approach to outpatient evaluation of common otolaryngology complaints as hospitals around the world are trying to limit the spread of the virus and to preserve health care resources. These changes raise a lot of questions regarding patient triage and treatment decisions in clinical situations when it is unclear if the workup and management can be postponed. In this communication, we present our approach to evaluation and triage of new patients with complaints concerning for salivary gland disease.