Malignant melanomas of the parotid: comparison of survival for patients with metastases from known vs unknown primary tumor sites

Is Primary Poorly Differentiated Sarcomatoid Malignancy of the Parotid Gland Sarcomatoid Undifferentiated/Dedifferentiated Melanoma? Report of Three Unusual Cases Diagnosed by Fine-Needle Aspiration Combined with Histological, Immunohistochemical, and Molecular Analyses

INTRODUCTION

Poorly differentiated primary sarcomatoid parotid malignancies are extremely rare. These tumors have not been consistently studied by morphology, immunohistochemistry, or molecular techniques.

CASE PRESENTATION

We report three unusual cases of parotid gland poorly-differentiated sarcomatoid malignancy investigated by fine-needle aspiration and studied histologically, by immunohistochemistry and molecular investigations. Aspirates showed poorly specific polymorphous sarcomatoid malignancy in all cases. Histologically, all cases were polymorphous high-grade malignancies, and additionally, one case showed epithelial structures and was finally classified as salivary carcinosarcoma. Immunohistochemistry showed classical melanocytic markers negativity but positivity for PRAME, CD10, and WT1 in all three tumors and for CD56 in two tumors, which can potentially be supportive of melanocytic origin. Although not entirely specific, molecular characterization also suggested the melanocytic lineage of these tumors.

CONCLUSION

Although rare, primary malignant melanoma of salivary gland was already described, but undifferentiated/dedifferentiated amelanotic forms are unknown in this localization up today. Further case reports of similar presentations are required to confirm the unequivocal primary origin of these obscure neoplasms in the parotid gland.

Malignant melanoma of parotid glands from a neglected lesion: A case report

Observing a metastatic malignant melanoma and its primary lesion at the same time is rare. The histopathological detection of any unusual pigmented lesion is critical.

Identification of Cancer Stem Cell Subpopulations in Head and Neck Metastatic Malignant Melanoma

Cancer stem cells (CSCs) have been identified in many cancer types. This study identified and characterized CSCs in head and neck metastatic malignant melanoma (HNmMM) to regional lymph nodes using induced pluripotent stem cell (iPSC) markers. Immunohistochemical (IHC) staining performed on 20 HNmMM tissue samples demonstrated expression of iPSC markers OCT4, SOX2, KLF4, and c-MYC in all samples, while NANOG was expressed at low levels in two samples. Immunofluorescence (IF) staining demonstrated an OCT4+/SOX2+/KLF4+/c-MYC+ CSC subpopulation within the tumor nests (TNs) and another within the peritumoral stroma (PTS) of HNmMM tissues. IF also showed expression of NANOG by some OCT4+/SOX2+/KLF4+/c-MYC+ cells within the TNs in an HNmMM tissue sample that expressed NANOG on IHC staining. In situ hybridization (n = 6) and reverse-transcription quantitative polymerase chain reaction (n = 5) on the HNmMM samples confirmed expression of all five iPSC markers. Western blotting of primary cell lines derived from four of the 20 HNmMM tissue samples showed expression of SOX2, KLF4, and c-MYC but not OCT4 and NANOG, and three of these cell lines formed tumorspheres in vitro. We demonstrate the presence of two putative CSC subpopulations within HNmMM, which may be a novel therapeutic target in the treatment of this aggressive cancer.

Melanoma of unknown primary

Formally described in the 1960s, melanoma of unknown primary (MUP) is characterized by the finding of metastatic melanoma within the lymph nodes, subcutaneous tissues, and other distant sites without an evident primary lesion. The most likely hypothesis of its etiology is an immune-mediated regression of the primary after metastasis has occurred. In addition, patients with MUP appear to have equivalent or better outcomes compared with patients with known primaries of a similar stage.

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.

Malignant melanoma of parotid gland in a child-our unique experience

Malignant melanoma (MM) of parotid gland is a rare condition. This pathology is often a result of secondary metastasis from primary lesions in the head and neck skin. A MM arising de novo in parotid gland is very rare. This malignant tumour is more prevalent in adults rather than children and it tends to have several distinct features. Treatment options are limited especially for an advanced lesion. Despite best treatments this condition carries a poor prognosis. This case details our experience in treating a child with MM of parotid gland without other primary cutaneous lesions.

Metastases of Melanoma to Head and Neck Mucosa: A Report of Short Series

Objectives

Metastasis of melanoma to the head and neck mucosa is a very unusual condition. The aim of this study was to report four cases of patients with metastatic melanoma in the head and neck mucosa treated at a single institution.

Methods

Clinical data were obtained from the medical records. All cases were histologically reviewed to confirm the diagnosis, and immunohistochemical reactions were performed in the cases submitted to biopsy.

Results

All patients were males and the mean age was 40.5 years old. The sites of the metastatic tumors were gingival mucosa, floor of the mouth, oropharynx, and larynx. Two tumors appeared as submucosal nodules with normal color; one lesion was a blackish nodular lesion, and one was shown to be an ulcerated lesion. The size of tumors ranged from 2.0 to 4.0 cm. All patients had developed systemic disease at time of diagnosis of metastatic tumor in the head and neck mucosa. Survival rates ranged from 2 to 19 months after the diagnosis of the metastatic mucosal melanoma in the head and neck region.

Conclusion

Although rare, patients with melanoma must be closely and regularly followed up, with careful routine examination of head and neck, because metastatic tumors in this region seem to be part of a lethal widespread metastatic disease.

Parotid metastasis of an amelanotic melanoma of the scalp: The great masquerader

BACKGROUND

Cutaneous melanoma is often characterized by its pigmented appearance; however, up to 8.1% of such lesions contain little or no pigmentation. Amelanotic melanomas, lesions devoid of visible pigment, present a diagnostic quandary because they can masquerade as many other skin pathologies. Recognizing amelanotic melanoma is even more clinically challenging when it is first detected as a metastasis to the secondary tissue.

METHODS

We report a rare case of metastasis of an amelanotic melanoma to the parotid gland.

RESULTS

A 75-year-old man presented with an 8-month history of a painless, mobile, hardened mass in the right parotid region. Histopathological analysis of a fine-needle aspiration biopsy of the parotid mass indicated that the mass was melanoma. Careful clinical and radiological examination revealed an 8 mm erythematous papule in the right temporal scalp, initially diagnosed by visual examination as basal cell carcinoma. After right superficial parotidectomy, neck dissection, and excision of the temporal scalp lesion, histological examination revealed the scalp lesion to be amelanotic melanoma.

CONCLUSION

Although metastatic amelanotic melanoma to the parotid gland is a rare diagnosis, the clinician should be familiar with this presentation to increase the likelihood of making the correct diagnosis and delivering prompt treatment.

Maxillofacial metastases: a retrospective review of one institution's 15-year experience

PURPOSE

Metastasis to the maxillofacial region is a rare occurrence. In our retrospective study of patients with metastasis to the maxillofacial region, the subjects were evaluated to define the clinical behavior patterns in response to the treatment given.

MATERIALS AND METHODS

A retrospective record review during a 15-year period (1990 to 2005) was conducted. The patients were selected for inclusion in the present study if they had histologically confirmed maxillofacial metastases.

RESULTS

In our retrospective study, during the 15-year period, 1,221 new patients with maxillofacial/oral cancer were seen and evaluated. Of these 1,221 patients, 26 (16 men and 10 women) were identified as having a histologically confirmed metastasis to the maxillofacial region, for an incidence of 2.1%.

CONCLUSIONS

Patients with metastasis to the maxillofacial region are often deemed to not be surgical candidates because of the extensive nature of the metastatic disease. We believe that surgical intervention plays a beneficial role in improving quality of life in a properly selected group of patients with metastasis to the maxillofacial region. In our case series, surgery was performed in about 50% of the patients, and palliation and radiotherapy were the most commonly used modalities.

Malignant melanoma of unknown primary site. To make the long story short. A systematic review of the literature

INTRODUCTION

Although more than 90% of melanomas have a cutaneous origin, occasionally it is discovered as a secondary deposit without evident primary site. The aim of this study was to systematically review published literature and analyse data on incidence, presentation, therapeutic interventions, survival and prognostic factors.

METHODS

We searched MEDLINE, (search terms Melanom*, unknown origin, unknown primary, indolent, occult) and the abstracts from major congresses of the last 4 years and perused the references of the retrieved relevant articles.

RESULTS

4348 patients with MUP were reported along with 132,643 patients with Melanoma of Known Primary (MKP). The incidence of MUP was 3.2%. The male to female ratio was 2:1 while the age peak was in the 4th and 5th decades. MUP patients harbouring nodal disease had a median overall survival ranging between 24 and 127 months, 5-year survival rate between 28.6% and 75.6% and 10-year survival rate between 18.8% and 62.9%. MUP patients with visceral disease had median survival times between 3 and 16 months, and 5-year survival rates between 5.9% and 18%. Presence of tumour regression in metastatic sites and low nodal burden were associated with favourable outcome. Potentially curative surgical treatment offered survival advantage in comparison to patients with residual metastatic foci. MUP patients who received adjuvant chemotherapy or radiotherapy paradoxically seemed to fare worse compared to patients observed.

CONCLUSIONS

This is the first review to bring together the information of 89 years and to analyze all the potential information accumulated. Although a well know entity no consensus is reached in order to describe MUP presentation, management or prognosis.

[Primary malignant melanoma of the parotid gland: a case report and review of the literature]

Malignant melanomas (MMs) of the parotid gland are relatively uncommon. They occur almost invariably as metastases from a primary tumour located in the region of the scalp or the mucous membranes of the nose, paranasal sinuses, or throat. Primary MMs arising in the parotid gland are extremely rare. It is assumed that they originate in the glandular tissue or in intraglandular lymph nodes. We present a case report and review of the literature on the diagnosis, treatment, and prognosis of intraparotid malignant melanoma. Diagnosis is based primarily on B-scan ultrasonography and fine-needle aspiration cytology. Patients with a cytological diagnosis of MM are further evaluated by magnetic resonance imaging and positron emission tomography and receive a thorough ear-nose-throat and dermatological examination. The treatment of choice is total parotidectomy and selective neck dissection. The effectiveness of adjuvant treatments such as radiotherapy, chemotherapy, or immunotherapy remains controversial. Patients with primary MMs of the parotid gland appear to have a better prognosis than those with parotid metastases from melanomas of the skin or mucous membranes.

Suspected case of primary malignant melanoma of the parotid gland

A patient presented with malignant melanoma of the parotid gland with no obvious primary lesions, which was treated by total parotidectomy with excision of skin. Despite radiotherapy for brain metastases and combination chemotherapy for lung and lymph node metastases, she died 13 months after the initial operation.

Distant metastasis of parotid gland tumors

The incidence of distant metastasis in head and neck cancer and especially in salivary gland cancer is relatively low in comparison to other malignancies. However, the presence of distant metastasis heralds a poor prognosis in head and neck cancer, with a median survival of 4.3-7.3 months. Treatment of these patients is usually performed in a palliative setting. Patients with malignant salivary gland tumors should have an X-ray or CT scan of the chest at their initial assessment to exclude the possibility of distant metastasis. The likelihood of developing distant metastasis is associated with high-grade tumors, such as adenoid cystic carcinoma, salivary duct carcinoma, high-grade mucoepidermoid carcinoma and tumors located in the submandibular gland, posterior tongue and pharyngeal tumors. A lower risk of developing distant metastasis is known for all other histological entities of salivary gland tumors. Nevertheless all patients who have a histologically confirmed malignant salivary gland tumor should have lifelong follow-up. On the basis of a clinical case regarding a patient with metastatic parotid gland cancer we present a review of the literature.

Parotid gland malignant melanomas

BACKGROUND

Malignant melanomas are relatively unusual tumors in the parotid gland. The majority of previously reported cases appear to represent metastatic lesions, often from cutaneous head and neck primaries.

METHODS

Retrospective clinicopathologic review of 12 cases of malignant melanoma involving the parotid gland encountered between 1980 and October 1999 at a tertiary referral center.

RESULTS

Patients consisted of 9 men and 3 women ranging in age from 30 to 84 years (median, 66 years). Eleven of 12 patients presented with a neck mass or nodule. In 9 of 12 patients, a cutaneous or conjunctival primary was noted in the head region. In 2 patients, a cutaneous melanoma and the parotid gland melanoma were diagnosed at the same time. In 1 patient, melanoma was initially diagnosed in the parotid gland, and a definite primary was not uncovered. All patients underwent excision of the parotid melanoma, which was accompanied by a lymph node biopsy or dissection in 10 out of 11 patients. Four patients received adjuvant radiotherapy, and 3 patients received adjuvant chemotherapy. Four of 11 patients had ipsilateral cervical lymph node metastasis at the time of parotid tumor resection, and 5 patients had involvement of intraparotid lymph nodes by metastatic melanoma. Tumors ranged in size from 0.3 to 2.5 cm in greatest dimension. Multiple parotid nodules were noted in 4 patients. All tumors were characterized by a diffuse proliferation of cells with abundant eosinophilic cytoplasm and prominent nucleoli. Four tumors demonstrated focal spindle cell regions. Intravascular and/or lymphatic involvement by tumor within the parotid gland was noted in 3 lesions. At last known follow-up, 6 patients had died with tumor at a median follow-up period of 11 months after parotid gland surgery. Four patients were alive with evidence of tumor at follow-up intervals of 4, 17, 21, and 113 months after parotid gland surgery. Two patients were alive with no evidence of residual tumor at 20 and 148 months of follow-up.

CONCLUSIONS

The majority of melanomas involving the parotid gland appeared to be associated with lymph node metastasis in and around the gland from a cutaneous primary in the head region. Prognosis is generally poor, although rare patients may survive a long period of time following surgery.