Management of parotid metastases from cutaneous melanoma of the head and neck

Primary malignant melanoma of the parotid gland: A case report and review of the literature

INTRODUCTION

Malignant melanomas (MM) of the parotid gland are rather rare and when discovered in the parotid gland without an identifiable primary site, they are considered even rarer.

PRESENTATION OF CASE

We report a case of a 27 years-old woman who was admitted to our department with a complaint of a painless mass in the parotid area. Clinical examination and radiological investigations found a mass compatible with pleomorphic adenoma. Treatment consisted of superficial parotidectomy. The evolution was marked by the appearance of a tumefaction regarding the scar. A total parotidectomy with neck dissection was performed and the histopathological examination found an intraglandular melanoma.

CONCLUSION

Primary malignant melanoma may represent a serious diagnostic challenge. It should be considered in the differential diagnosis of parotid tumors even if it's rare.

Determining the number and distribution of intraparotid lymph nodes according to parotidectomy classification of European Salivary Gland Society: Cadaveric study

BACKGROUND

To investigate the distribution of the parotid gland's intraglandular lymph nodes using the parotidectomy zones determined by the parotidectomy classification of the European Salivary Gland Society (ESGS).

MATERIALS AND METHODS

A total of 128 parotid glands were dissected from 64 fresh cadavers, by bilateral parotidectomy without additional incision within the standard autopsy procedure, and categorized.

RESULTS

Eighty-six percent of the IGLNs were located in the superficial lobe and 14% in the deep lobe. An average of 7.09 ± 3.55 IGLNs were found for each of the gland; there were 6.11 ± 3.28 in the superficial lobe and 0.98 ± 1.46 in the deep lobe. While the most common lymph nodes were found in level 2 with 47.7%, only 5% of IGLNs were at level 4. According to the proposed modification, the most common lymph nodes (35.24%) were located at level 2B.

CONCLUSION

Level 2B was found to contain significantly more lymph nodes than other levels, which has not been evaluated before in literature.

[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.

[Secondary malignant tumors of the parotid]

AIM OF THE STUDY

Secondary malignant tumors of the parotid gland are uncommon. They arise from primary tumors located in the head and neck or from distant primary tumors. The formers are dominated by squamous cell carcinomas and melanomas, the latters by renal and lung cancers. Distinction between malignant primary tumors and metastasis of other primary tumors to the parotid gland is very important to appreciate, because the result of this will change therapeutic procedure and the evaluation of prognosis.

METHODS

A series of 23 patients with tumors metastatic to the parotid gland are reported. All clinical and pathological data were reviewed. The management of secondary tumors of the parotid gland and the results were analyzed in order to try to identify common features and implications for management.

RESULTS

The most frequent histologic types were squamous cell carcinoma and melanoma. Most primary tumors occurred in the head and neck. Metastasis to the parotid gland presented with a median time of 18 months after diagnosis of the primary tumor. All the patients had a parotid mass. No patient had facial nerve weakness. Parotid metastases were treated by superficial parotidectomy with preservation of the facial nerve in all cases, associated in 14 cases with a homolateral selective neck dissection and in 6 cases with a homolateral radical neck dissection. Twenty-one patients were submitted to radiation therapy. Seven patients died after the treatment: in 3 cases, death was due to a local recurrence with cervical relapse; 4 patients presented cervical and metastatic lesions.

CONCLUSION

This retrospective review confirmed that patients with involvement of cervical nodes and metastatic parotid tumors have a worse prognosis than those without involvement of cervical nodes. The addition of postoperative radiotherapy provides no additional benefit.

Melanoma metastatic to cervical lymph nodes: Can radiotherapy replace formal dissection after local excision of nodal disease?

BACKGROUND

Completion cervical lymphadenectomy is usually performed after excisional biopsy of nodal metastases from melanoma. Radiation (XRT) might be effective for some patients in lieu of formal lymph node dissection.

METHODS

Thirty-six patients with parotid or cervical node metastases from melanoma were treated with excision of nodal disease and postoperative XRT without formal lymph node dissection. Radiation was delivered to the primary site (if known), the site of nodal excision, and the undissected ipsilateral neck.

RESULTS

With a median follow-up of 5.3 years, the disease recurred within the regional basin in two patients and at distant sites in 14 patients. The actuarial 5-year regional control and distant metastasis-free survival rates were 93% and 59%, respectively. Two patients had a clinically significant side effect develop.

CONCLUSIONS

The results of this study suggest that selected patients may receive regional XRT after local excision of nodal disease from melanoma in lieu of formal lymph node dissection.

Melanoma arising within the parotid salivary gland--a case report and review of management

Melanoma arising within the parotid salivary gland is an unusual, though well-recognized phenomenon. Melanocytes are derived, embryologically, from neural crest tissue and are not a constituent of normal salivary tissue. It is, therefore, reasonable to assume that a melanoma within the parotid has arisen either as a metastasis to a parotid lymph node or as a metastasis to the gland itself. The primary lesion cannot always be identified--spontaneous regression of melanomas is an equally well-recognized phenomenon. This is a report of such a case, with a review of the management.

The deep parotid lymph nodes: an anatomical and oncological study

In order to better define the anatomical and clinical importance of the deep parotid lymph nodes, the surgical specimens obtained from a series of 18 total parotidectomies were evaluated. In 10 cases primary parotid pathology was found, whereas in the remaining eight cases metastases to glandular lymph nodes were present. One hundred and forty-nine lymph nodes, in all, were identified (range 3-14, average 8.2, mean 8), 118 located in the superficial parotid lobe (range 3-11, average 6.5, mean 7), and 31 in the deep lobe (range 0-5, average 1.7, mean 2). In the group of patients with oncological pathology, of the total 64 lymph nodes examined, 21 were found to be sites of metastasis, 11 in the superficial lobe, and 10 in the deep lobe. The above findings confirm the anatomical and oncological importance of the deep parotid lymph nodes, and highlight the necessity of a total parotidectomy in all cases in which intraglandular spread of lymph node metastases is certain or suspect.