Primary Squamous Cell Carcinoma of Submandibular Salivary Gland: A Case Report

Primary squamous carcinoma of the submandibular gland: A case report

The uncommon occurrence of primary squamous carcinoma of the submandibular gland makes it a challenge to diagnose and treat. Clinical as well as histopathological assessments are key elements for the diagnosis. Although no clear treatment guidelines exist, surgical excision with a neck dissection is the cornerstone of the treatment with or without adjuvant therapy. In this paper, we report a rare case of a primary squamous carcinoma in an 82-year-old lady with no history of smoking or alcohol use, who presented with a right sided cervical swelling of 3-month duration. An ultrasound guided fine needle aspiration cytology was negative, as well as a panendoscopy with systemic biopsy of the base of tongue and the homolateral palatine tonsil. In addition, a blind fine needle aspiration cytology from the mass during the panendoscopy was performed and was positive for squamous cell carcinoma. A PET scan showed hypermetabolism of the right submandibular gland with no distant lesions. Therefore, a submandibular gland excision was performed with a frozen section histopathological examination in favor of squamous cell carcinoma, therefore the intervention was completed by a selective neck dissection. High clinical suspicion should be present while dealing with this rare entity, as well as not underestimating the poor outcomes associated with it.

A Rare Case of Primary Squamous Cell Carcinoma of the Submandibular Salivary Gland: Brief Overview of Diagnostic Ambiguity and Treatment Challenges

Primary squamous cell carcinoma of the submandibular salivary gland is a rarity with obscure etiology and atypical presentation. The features include a progressively enlarging swelling in the lateral neck just below the mandible, which is rarely tender. Surgery is the mainstay of the treatment, and the role of adjuvant therapies is not defined. Precise diagnosis demands a step-by-step systematic approach to exclude the presence of any index tumor. A 65-year-old countryside male presented to our institute with a complaint of submandibular swelling of the right side. After the exclusion of the primary, he was treated surgically with safe margins, ipsilateral comprehensive neck dissection, and adjuvant therapy. One month post-chemoradiotherapy, the patient developed a second primary in the contralateral submandibular region with lung metastasis and succumbed to death due to malignant cachexia. The stage of the disease at presentation, bone and skin involvement, lymphovascular invasion, poorer differentiation, and distant metastasis are associated with dismal outcomes. An early diagnosis and comprehensive surgical management with adjuvant chemoradiotherapy must be accomplished.

Primary squamous cell carcinoma of the salivary gland: immunohistochemical analysis and comparison with metastatic squamous cell carcinoma

BACKGROUND

Primary squamous cell carcinoma (SCC) of the salivary gland is a rare disease, and distinguishing primary SCC from metastatic SCC is difficult. This study investigated the histological and immunohistochemical differences between primary and metastatic salivary gland SCC to improve the accuracy of diagnosis and to explore the pathogenesis of this disease.

METHODS

Data of 16 patients who underwent surgery for SCC of salivary glands between 2000 and 2018 at Asan Medical Center were retrieved. Eight patients had a history of SCC at other sites, and eight patients had only salivary gland SCC. Immunostaining for p16, p53, androgen receptor (AR), gross cystic disease fluid protein 15 (GCDFP-15), and c-erbB2, as well as mucicarmine staining, were compared between the two groups.

RESULTS

Most tumors were located in the center of the salivary glands with extraparenchymal extension. The histology of primary SCC of the salivary gland was consistent with moderately differentiated SCC with extensive desmoplastic reaction and peritumoral inflammation. Involvement of the salivary gland ducts and transition into the ductal epithelium were observed in two cases. Metastatic SCC resembled the primary tumor histologically and was associated with central necrosis. Both groups exhibited negative mucin staining. Two, one, and one primary SCC case exhibited AR, GCDFP-15, and c-erbB2 positivity, respectively.

CONCLUSIONS

A subset of primary SCCs originated in salivary ducts or was related to salivary duct carcinoma. Distinguishing primary from metastatic SCC of the salivary gland is difficult using histologic features and immunoprofiles. A comprehensive review of the medical history is essential.