Metastatic Cancer – Melanoma
Gross Anatomy of Metastatic Melanoma
Lyz Boyd and Jennifer Kong
Learning Objectives
At the end of this section, you will be able to:
- Name common sites of metastasis.
- Upon visual inspection, identify key features of metastatic melanoma in organs.
Melanoma frequently metastasizes to the liver, lungs, and brain. However, metastases can also occur in other organs. The DHPLC collection is fortunate to have specimens (from various patients) of melanoma metastases in the liver, brain, lungs, kidneys and the heart. Regardless of the metastatic site, the melanoma will look similar to that seen in the primary site (i.e. skin). In essence, metastases will look like moles in these organs which normally would NOT have any melanocytes present.
Metastatic Melanoma in Liver (DHPLC Specimen: M0935) and Lung (DHPLC Specimen: A0901C) by Lyz Boyd, licensed under All rights reserved
Metastatic Melanoma in Brain (DHPLC Specimen: P0932 ) and Heart (DHPLC Specimen: B0901) by Lyz Boyd, licensed under All rights reserved
Melanoma can metastasize to other, less common, sites. The following images are from different patients, all with metastatic melanoma.
Recall that there are melanocytes in the uvea of the eye. Although less common, melanoma can arise within the eye and metastasize to any of the pre-mentioned locations.
- Common sites of metastasis are liver, lungs, and brain.
- Metastasis can occur to other organs, provided that they have blood or lymphatic flow. These abnormal melanocytes will grow in this new location, regardless of whether melanocytes were previously present. Thus melanoma will visually appear similar to those of the original site, but now in a distant organ: dark, irregularly shaped and sized moles of varying colours.
- Melanoma can also arise from tissues which also have melanocytes – the eye being an example of a less common origin of melanoma.
1. Which of the following organs is NOT a common site for metastases?
- Brain
- Liver
- Bone marrow
- Skin
2. Why can melanoma develop in the eye?
- There are melanocytes present in the eye which can get damaged and develop cancerous changes.
- The eye is highly vascularized with slow blood flow – an ideal location for metastatic cells to colonize.
- The eye has lots of lymphatic flow and mestatic melanoma tends to travel in the lymph.
- The eye is physically close to where primary melanoma cancers develop: on the upper face.
3. Fill in the blanks.
You are a surgeon, doing a surgery on the liver biliary tree trying to discover why the patient is experiencing jaundice and liver dysfunction. During the surgery, you find a lesion that you suspect is metastatic melanoma. This is because the lesion is _____ in colour with lots of blood vessels present. You take a biopsy of this lesion and send it to a pathologist for examination. The pathologist notices the presence of _____ in both the liver lobules and biliary tract. With these results, medical imaging is arranged to look for metastases in the _____ and ask if there are any neurological symptoms.
Answer Key
- Skin
- There are melanocytes present in the eye which can get damaged and develop cancerous changes.
- Black, melanocytes, brain
