Lymphoepithelioma-like carcinoma of the salivary gland: is radiotherapy alone adequate?

Could definitive radiotherapy be a treatment option for lymphoepithelial carcinoma of major salivary gland: Comparison of clinical outcomes of upfront surgery and upfront chemoradiotherapy

OBJECTIVES

The optimal treatment and associated clinical outcomes for lymphoepithelial carcinoma of the major salivary gland (LECSG) are currently unclear. As such, the purpose of this study was to assess the survival rates of LECSG patients who received either upfront surgery or upfront chemoradiotherapy (CRT).

MATERIALS AND METHODS

In this retrospective study, we analyzed cases of LECSG patients treated at our center from January 2010 to April 2021. The cumulative incidences of overall survival rate (OS) and locoregional failure-free survival rate (LRFFS) were evaluated using the Kaplan-Meier method. In order to balance potential risk factors between the treatment groups, we conducted propensity score matching (PSM) at a 1:1 ratio.

RESULTS

The study enrolled a total of 107 patients, among whom 24 received surgery alone, 56 underwent surgery combined with postoperative radiotherapy, and 27 underwent definitive radiotherapy. The 5-year LRFFS rate and 5-year OS rate for the entire cohort were 86.6% and 84.4%, respectively. Following PSM, the 5-year LRFFS and OS rates for the upfront CRT cases were comparable to those of upfront surgery, both before and after matching. However, the upfront surgery group showed a tendency toward more de novo facial nerve injury and post-treatment facial nerve injury.

CONCLUSION

The results of this study suggest that upfront CRT is as effective as upfront surgery in terms of locoregional control and overall survival for LECSG patients. Therefore, upfront CRT could be considered a viable treatment option, potentially avoiding the risks associated with surgical intervention.

Imaging Features of Lymphoepithelial-Like Carcinoma of the Salivary Glands

OBJECTIVE

Lymphoepithelial-like carcinoma of the salivary glands (LELCSG) is a rare tumour of unknown aetiology. No studies have reported the imaging features of primary LELCSG.

METHODS

The clinical information and imaging features of eight patients with LELCSG were reviewed. Computed tomography (n = 4 patients) and magnetic resonance imaging (n = 4 patients) features were analysed by two radiologists to identify the location, number, size, shape, boundary, signal intensity and enhancement of LELCSG.

RESULTS

The study included four women and four men, and the mean size of the tumours was 32.88 ± 3.41 mm (range, 27-38 mm). The tumours affected the parotid gland in six cases and the submandibular gland in two cases. The eight cases were evaluated by radiologists. All tumours were lobulated; three had clear edges and five had blurred edges. There was no necrosis in six tumours, while two tumours exhibited slight necrosis without bleeding. All eight tumours showed multiple nodular changes and extensive fusion. Four tumours with magnetic resonance imaging (MRI) were isointense or slightly hyperintense on T1-weighted imaging (T1WI) and obvious homogeneous enhancement on contrasted enhanced T1WI scan, while slightly hyperintense on T2-weighted imaging (T2WI). The other four lesions were isodense on computed tomography (CT) scan. The degree of enhancement varied among the eight tumours. The necrotic zones of the eight tumours did not exhibit any enhancement.

CONCLUSIONS

LELCSG is a lobulated, multi-nodular tumour, with some fused nodules. LELCSG lesions showed isointensity or slight hyperintensity on T1WI MRI, slight hyperintensity on T2WI MRI and isodense on CT scan. Larger tumours may exhibit some necrosis, but the necrotic cysts were relatively rare. Uniform enhancement was observed in non-necrotic areas on enhanced CT and MRI scan. The multi-nodular feature may be valuable for diagnosis.