A Rare Presentation of Metastatic Melanoma
Abstract:
The prevalence of melanoma is on the rise in western society especially as the younger generation ages. Although considered a malignancy of the skin, melanoma can spread to multiple systems throughout the body due to the location of melanocytes in multiple organ systems. Therefore, it is essential for physicians to detect malignant melanoma at the earliest stage in order to decrease the risk of metastasis. We describe a case of a 69-year-old gentleman with a significant past medical history of stage 1a melanoma diagnosed 5 years ago, who presents with multiple nodal masses. The patient is diagnosed with metastatic melanoma after discovery of enhancing lesions on CT imaging of the head, neck, and abdomen confirmed via biopsy of the supraclavicular node. Although the stage 1a melanoma has a low rate of recurrence and metastasis, it is paramount that physicians continue to due serial, thorough dermatologic exams even after successful excision of the primary tumor.
The prevalence of melanoma is on the rise in western society especially as the younger generation ages. Although considered a malignancy of the skin, melanoma can spread to multiple systems throughout the body due to the location of melanocytes in multiple organ systems. Therefore, it is essential for physicians to detect malignant melanoma at the earliest stage in order to decrease the risk of metastasis. We describe a case of a 69-year-old gentleman with a significant past medical history of stage 1a melanoma diagnosed 5 years ago, who presents with multiple nodal masses. The patient is diagnosed with metastatic melanoma after discovery of enhancing lesions on CT imaging of the head, neck, and abdomen confirmed via biopsy of the supraclavicular node. Although the stage 1a melanoma has a low rate of recurrence and metastasis, it is paramount that physicians continue to due serial, thorough dermatologic exams even after successful excision of the primary tumor.
Melanomas constitute only 5% of skin cancers but account for a majority of skin cancer related deaths worldwide 1. Mortality from melanoma is determined primarily by the stage at diagnosis and with its rising prevalence, early recognition and management is of ought most importance.
Figure 1: Unremarkable CT of abdomen & pelvis with 3d reconstruction on 5/2010.
Melanoma results from malignant transformation of melanocytes, therefore it can arise anywhere in the body with melanocytes. As with all cancers, the prognosis and treatment plan for patients with melanoma are determined by the stage of cancer at presentation. Accurate staging is critical in determining the patient’s prognosis. Melanoma is primarily staged by the depth of invasion and the presence or absence of ulceration in the primary lesion.
Below we will discuss a patient who presented with a 0.52 mm malignant melanoma that was successfully excised. This particular patient had stage 1 disease that is considered to have a relatively good prognosis. After six years, he returns with a painless right supraclavicular node that has likely arisen from metastatic melanoma.
Figure 2: Head CT showing cerebral metastasis within right frontal lobe (left) and left high parietal lobe (right) on 2/2012.
This is a 69-year-old Caucasian male who presented to Emergency Department with a painless right supraclavicular mass. The patient does not recall how long he has had the mass. He denied any cough, hemoptysis, recent weight loss or sick contacts. His surgical history was significant for a previous wide excision of an invasive 0.5 mm melanoma on the cheek 5 years prior to presentation. On exam, there is a non-tender, immobile right neck and chest wall mass. No focal neurological signs are elicited. A complete head to toe skin evaluation revealed no other suspicious lesions. A CT scan of the chest, abdomen, neck, and head (Figures 1-4) revealed a large edematous tumor in the right frontotemporal portion of his brain, as well as a large right adrenal mass with multiple intra-abdominal and retroperitoneal masses suggestive of metastatic melanoma. An excisional biopsy of the chest wall mass was performed and pathology confirmed the diagnosis of metastatic melanoma. A mediport was placed and he was referred to hematology oncology for chemotherapy and CNS radiation therapy.
Figure 3: Neck CT scan showing mild lymphadenopathy
at the base of the neck posteriorly on right and left sides. Largest nodes measure approximately 16 mm.
According to the American Cancer Society, melanoma has a 95% ten-year survival rate for stage 1a melanoma following excision with appropriate margins as well as very low recurrence rate following excision 2. However, given his history and the CT findings, metastatic melanoma remained at the top of our differential diagnosis. Other causes of cervical lymphadenopathy including but not limited to lymphoma, thymoma, human immunodeficiency disease, lung cancer, and other neoplasms should also be considered. It should also be noted that while wide excision (1 cm margin) is considered curative for stage 1a melanoma, local recurrence as well as metastasis is not uncommon. One study reported a 10-year recurrence rate for stage 1 melanoma to be as high as 4.7% 3. In this study, they were able to identify certain risk factors associated with recurrence following excision of a stage 1 melanoma. The risk factors listed include male sex, location in the head and neck region, and melanoma type (acrolentiginous and lentigo malignancy). Given these findings, regular follow up physical exams post excision is necessary for early detection of recurrence. It is recommended that patients with stage 1 melanoma be evaluated every 6 months for 2 years, then annually 3. Early detection of locoregional recurrence can improve survival by detecting disease prior to lymph node or distant metastasis.
Figure 4: Abdominal CT scan showing multiple metastatic lesions involving bilateral adrenal glands, mesenteric lymph nodes, right femoral lymph node, and retroperitoneal fat below the left kidney.
Generally considered uncommon, stage 1a melanoma can recur with devastating consequences, especially in a subset of patients (i.e. men with head and neck melanoma of acrolentiginous or lentigo malignant type). In addition to adequate excision with at least 1 cm margins, thorough routine follow up skin exams are necessary for detection of early recurrence.
- American Cancer Society. Melanoma Skin Cancer. American Cancer Society. http://www.cancer.org/cancer/skincancer- melanoma/detailedguide/melanoma-skin-cancer-key-statistics. Published September 9, 2012. Accessed October 15, 2012.
- American Cancer Society. Melanoma Skin Cancer. American Cancer Society. http://www.cancer.org/cancer/skincancer- melanoma/detailedguide/melanoma-skin-cancer-survival-rates. Published September 9, 2012. Accessed October 15, 2012.
- Schmid-Wendtner, M H Baumert, J eberle, G Plewig, M Volkemandt, and C A Sander. “Disease Progression in Patients with Thin Cutaneous Melanomas (tumour Thickness < or = 0.75 mm): Clinical and Epidemiological Data from the Tumour Center Munich 1977-98.” The British Journal of Dermatology. October 2003; 149: no. 4; 788-793.