[Metastasis to the parotid gland]

Metastases of Cutaneous Squamous Cell Carcinoma Seem to be the Most Frequent Malignancies in the Parotid Gland: A Hospital-Based Study From a Salivary Gland Center

Malignant parotid tumors account for approximately 20% of all parotid lesions. In addition to the various primary parotid lesions there are secondary parotid malignancies, such as metastases or lymphomas. Data on histopathological distribution of all malignancies-including secondary parotid lesions-is limited. Recent evidence indicated a rising surgical incidence of secondary parotid malignancies. This study aims to review the distribution of malignancies in parotid resections from a salivary gland center. A retrospective review of prospectively collected data for all patients who had received parotidectomy between 2014 and 2019 was performed. Histopathological distribution was displayed separately for all parotid malignancies and for primary parotid malignancies. Further, patients` characteristics were compared between benign and malignant parotid lesions and between the two most common malignant parotid lesions. Out of 777 patients, 614 (78.9%) patients had a benign and 164 (21.1%) patients had a malignant parotid lesion. The most common parotid malignancy was metastatic cutaneous squamous cell carcinoma (cSCC) accounting for 35.4% of all parotid malignancies. 71.5% of all malignant lesions were secondary malignancies. Patients with metastatic cSCC were significantly older (p < 0.001) and significantly more likely to be male (p < 0.001) than patients with primary parotid malignancies. No significant difference was found when the lesion size of metastatic cSCC was compared to primary parotid malignancies (p = 0.216). The present study shows the high prevalence of secondary parotid malignancies in patients who had received parotidectomy. Furthermore, it confirms a rising surgical incidence of metastatic cSCC to the parotid gland in a series from a salivary gland center. At this time, parotid surgery for malignant lesions is more likely to be performed for metastases than for primary parotid malignancies.

The Clinical Significance of Incidental Parotid Uptake in a PET/CT Study: A Diagnostic Algorithm

BACKGROUND

Patients diagnosed with cancer do not have sufficient clinical data for the management of incidental parotid lesions. We aimed to reveal the importance of randomized parotid lesions encountered during oncologic F-18 fluorodeoxyglucose positron emission tomography (FDG PET/CT) imaging in our clinical practice and the diagnostic algorithm of such lesions.

METHODS

We performed a database search of PET/CT records generated from 2009 to 2015 for "parotid" in reports of patients who underwent PET/CT examination for a known malignancy elsewhere, or cancer screening.

RESULTS

Incidental parotid FDG uptake on PET/CT had a prevalence of 1.1%. The incidence of parotid metastasis in our series was 36.4%, and 75% of them had malign melanoma metastasis. Of the 11 cases, 5 were of Warthin tumours, and Warthin tumours showed stronger GLUT1 expression than metastatic parotid lesions.

CONCLUSION

In patients with malignancy elsewhere, focal involvement of FDG by the parotid gland, especially if malignant melanoma or SCC is absent, should not be considered a metastatic disease without histopathologic confirmation. If parotid disease would change the patient's treatment plan and disease stage, the parotid lesion should be evaluated by additional methods, such as fine needle aspiration biopsy.

The rising incidence of parotid metastases: our experience from four decades of parotid gland surgery

Secondary neoplasia in the parotid gland is increasingly frequent. We examined outcomes from 40 years of parotid surgery to analyse patterns for metastasis, review the staging procedure and discuss management. We retrospectively examined 772 consecutive cases of parotid surgery in a university hospital between 1975 and 2015 and assessed changes in incidence and management over four decades. In all, 71% percent of patients were male and 29% were female, with a mean age of 68 years, aged between 23 and 93 years. We diagnosed 683 parotid tumours of which 15.8% (n = 108) were malignant; 44% (n = 48) of all malignant lesions were metastases. The incidence of malignant tumours rose from 8% in the first decade, 14% in the second, 17% in the third to 21% in the fourth. The incidence increased even further from 10% in the first to 57% in the final decade. Most frequent tumours were metastases of squamous cell carcinoma (79%), and the majority of these lesions (87%) arose from above the clavicle, with 30 primary tumours in the skin. In most cases, the skin tumour had been excised between 6 and 24 months prior to parotid metastasis. Management consisted of surgery with neck dissection. 48 patients (67%) received adjuvant therapy, but despite aggressive multimodal treatment, disease progressed in the majority of cases, in 57% squamous cell carcinoma of the skin primaries, 67% of mucosal primaries above the clavicle and 83% of infraclavicular primaries. Parotid malignant tumours are increasing in incidence, mostly due to a rise in metastatic malignant tumours within the parotid gland, most of which are metastases of skin tumours, commonly squamous cell carcinoma. Despite multimodal therapy, their recurrence and progression rate remains high. We propose inclusion in head and neck follow-up in all cases of head and neck skin cancers.

Parotid gland metastases of distant primary tumours: A diagnostic challenge

OBJECTIVE

Metastatic disease is common among parotid malignancies. The majority of primary tumours are located in the head and neck, but primary tumours below the clavicle must also be considered, especially in histological types not usually found in primary parotid or skin tumours.

METHODS

We performed 644 consecutive parotidectomies between 1980 and 2012. Benign tumours were found in 555 patients (86%) and malignant tumours in 89 patients (14%).

RESULTS

Of 89 malignant tumours, 39 were metastases (44%). In 5 cases, the primary tumour was located below the clavicle (6% of malignant tumours). A carcinoma of the bronchus was subsequently diagnosed in three patients: one patient had breast carcinoma and one renal cell carcinoma.

CONCLUSION

The majority of metastases in the parotid gland arise from primary tumours of the head and neck. In 10-20% of metastases, the primary tumour arises below the clavicle. Parotid metastases can be the first clinical manifestation of a malignant tumour, and can also occur years after curative intent treatment. Histopathology and immunohistochemistry will offer clues to a possible metastatic process and to primary tumour location. Parotidectomy with complete excision of the tumour can be a curative measure or form an essential part of symptom control and should be considered in all but the most moribund patients.

Challenges in the differential diagnosis of interdigitating dendritic cell sarcoma of intraparotid lymph node vs. metastatic malignant melanoma with unknown primary site

Interdigitating dendritic cell sarcoma (IDCS) is an uncommon form of malignant histiocytosis affecting dendritic cells. The parotid gland more frequently than other salivary glands has metastasis from extraparotid tumours, which in 80% of cases are melanomas and squamous cell carcinomas. Herein we report our case, a 64-year-old woman who presented with a short history of fluctuating in size swelling below her right ear. Ultrasound scan showed a loculated cystic lesion extending in the parotid parenchyma. Fine needle aspiration (FNA) revealed appearances that were highly suspicious of malignancy, therefore MRI scan was arranged, and parotidectomy planned. The histology of tumour was a malignant spindle cell neoplasm, with immunohistochemical features highly suggestive of metastatic malignant melanoma with divergent differentiation. The challenges in the differential diagnosis of IDCS of intraparotid lymph node vs. metastatic malignant melanoma with unknown primary tumour are described here.

The rarity of this neoplasm figures highlights the importance of describing all new cases putting special emphasis on the steps to be taken in order to shorten the diagnosis, management and treatment process.

Atypical presentations and rare metastatic sites of renal cell carcinoma: a review of case reports

Renal cell carcinoma is a potentially lethal cancer with aggressive behavior and a propensity for metastatic spread. Due to the fact that the patterns of metastases from renal cell carcinomas are not clearly defined, there have been several reports of cases of renal cell carcinoma associated with rare metastatic sites and atypical presenting symptoms. The present review focuses on these atypical rare clinical presentations of renal cell carcinomas both at the time of diagnosis of the primary tumor but also in the years after radical nephrectomy.

[Tumoral pathology of salivary glands. Our experience]

INTRODUCTION AND OBJECTIVES

We report a descriptive epidemiologic study of 63 patients with major and minor salivary gland tumours diagnosed at our centre over the last ten years.

METHODS

The data collected from all patients included gender, age, location, histopathology, diagnostic procedures, treatment and follow-up.

RESULTS

Among the 38 males and 25 females, we found 39 with benign tumours and 24 with malignant tumours. Most of these tumours (42; 67%) arose in the parotid gland, 12 (19%) in the submaxillary gland, 7 (11%) in the palate and 2 (3%) in external auditory canal. The mean age was 54 years for benign tumours and 80 years for malignant ones. The most common benign tumours found were pleomorphic adenomas (67%) whereas epidermoid carcinoma (54%) followed by lymphomas (25%) were the most frequent among malignant tumours.

CONCLUSIONS

We have found two main differences with previously reported studies: the elevated mean age of patients with malignant tumours and, probably as a result of this advanced age, the high incidence of squamous cell carcinoma due to metastatic dissemination of skin cancers.

Head and neck manifestations of distant carcinomas

Metastatic tumors to the head and neck from distant carcinomas are rare lesions that epitomize the "zebras." They represent a diagnostic and therapeutic challenge for clinicians and health providers. These lesions usually rank low in the differential diagnosis list, but a history of cancer should prompt clinicians about the possibility of a metastatic lesion from a distant carcinoma. The presence of these lesions usually represents a poor prognosis. The surgeon's role in treating these lesions is to improve or maintain the patient's quality of life, taking into consideration the overall prognosis.

Metastatic adenocarcinoma of parotid gland originating from the ampulla of vater: case report and review of the literature

AIM

To report a rare case of metastasis from an adenocarcinoma of the ampulla of Vater to the parotid gland.

PATIENTS AND METHODS

In February 2004, a 61-year-old male underwent Whipple surgery due to a grade II adenocarcinoma of the ampulla of Vater (stage IB:pT2N0M0). Post surgery, the patient did not receive any adjuvant treatment, but was followed up regularly. Two years post surgery, an abdominal computed tomography (CT) revealed metastatic hepatic lesions. The patient subsequently underwent three lines of chemotherapy without significant response. Two months after chemotherapy (April 2007), the patient complained of a painless lump in the parotid region that was progressing fast. Not long after presentation, the mass caused severe local pain that was hardly managed with opioid analgesics. A head and neck CT depicted a 5 x 4 x 3 cm solid mass that was infiltrating the masseter and pterygoid muscles, the mandible, and parotid gland. Fine needle aspiration showed that the infiltrating mass was due to an adenocarcinoma of the ampulla of Vater. The patient subsequently received palliative radiotherapy (50.4 Gy), achieving a considerable therapeutic response.

CONCLUSIONS

Metastasis of adenocarcinoma of the ampulla of Vater to the parotid gland has not to our knowledge been previously reported. Radiotherapy offers an excellent means of palliation with minimal morbidity.