Malignant MelanomaMalignant MelanomaDr Foroogh MousaviDr Foroogh Mousavi

What is melanomaWhat is melanoma

Skin malignancy that is the result of Skin malignancy that is the result of uncontrolled multiplication of melanocytes.uncontrolled multiplication of melanocytes.

Melanocytes are a group of cells in the Melanocytes are a group of cells in the superficial layer of the skin that produce superficial layer of the skin that produce melanin ( a dark pigment) as a response to melanin ( a dark pigment) as a response to ultraviolet light.ultraviolet light.

Other forms: ocular , visceral Other forms: ocular , visceral

Etiology Etiology

Genetics : p16,p19,ras.Genetics : p16,p19,ras.

UV exposure , by various mechanisms UV exposure , by various mechanisms including damaging melanocytes DNA.including damaging melanocytes DNA.

Sunburn : intermittent, blistering sunburns.Sunburn : intermittent, blistering sunburns.

Warning signs: changing moles, positive Warning signs: changing moles, positive family history, previous history of melanomafamily history, previous history of melanoma

EpidemiologyEpidemiology

Highest incidence rate in Highest incidence rate in Queensland ,Australia: 57 per100,000.Queensland ,Australia: 57 per100,000.

Rapid increase in incidence worldwide, only Rapid increase in incidence worldwide, only second to lung cancer. Risk: 1 in 1500 in second to lung cancer. Risk: 1 in 1500 in 1935 , 1 in 75 in 2000.1935 , 1 in 75 in 2000.

Gender demographics :M>FGender demographics :M>F

Average age of diagnosis : 57 yrs, rare in <10 Average age of diagnosis : 57 yrs, rare in <10 yrs.yrs.

DiagnosisDiagnosis

Clinical: checking suspicious lesion , ABCD.Clinical: checking suspicious lesion , ABCD.

Pathology/biopsy : confirms diagnosisPathology/biopsy : confirms diagnosis

Imaging: staging and spreadImaging: staging and spread

Staging Staging

According to skin layers involved ( Clarke):According to skin layers involved ( Clarke): Level I : epidermis, Level II to IV : dermis, Level Level I : epidermis, Level II to IV : dermis, Level

V: subcutaneous fatV: subcutaneous fat

According to depth (Breslow): 0.75 mm, 0.76-According to depth (Breslow): 0.75 mm, 0.76-1.5, 1.51-4mm, > 4mm.1.5, 1.51-4mm, > 4mm.

TNM :Thickness and ulceration, Nodes , TNM :Thickness and ulceration, Nodes , MetastasisMetastasis

Nodal assessmentNodal assessment

Sentinel node biopsy : Sentinel node biopsy : Indicated if >1mm thick Indicated if >1mm thick Sentinel node : the very first draining lymph nodeSentinel node : the very first draining lymph node Blue dye or Tc radioisotopeBlue dye or Tc radioisotope

Melanoma on medical Melanoma on medical imagingimaging

Chest radiograph : Chest radiograph :

-Routinely obtained on diagnosis -Routinely obtained on diagnosis

-Usually negative on stage I and II: usually -Usually negative on stage I and II: usually negative , provides a baseline for future negative , provides a baseline for future comparison.comparison.

- Important to obtain in stage III and higher : - Important to obtain in stage III and higher : first metastatic site are lungs.first metastatic site are lungs.

Melanoma on medical Melanoma on medical imagingimaging

CT CT Head : brain mets assessmentHead : brain mets assessment Chest: indicated in stage IV disease to detect Chest: indicated in stage IV disease to detect

asymptomatic metsasymptomatic mets Abdomen : stage III, in-transit and locally Abdomen : stage III, in-transit and locally

recurrent recurrent

usually low yield but provide a base line.usually low yield but provide a base line. Pelvis : only when primary region is below the Pelvis : only when primary region is below the

waistwaist

58 year old female who developed left-handed weakness. A. Non-contrast melanoma on CT, usually has a hemorrhagic appearance. B. Contrast enhanced CT , mets show contrast enhancement due to destruction of blood-brain barrier.

AA B

Medical imagingMedical imaging

MRI : brain MRI : brain

Only in case of known mets or symptomatic Only in case of known mets or symptomatic patients.patients.

A 55 yr female with melanoma of right leg and hemorrhagic metastasis to the brain. T1: large hyperintense lesion left posterior parietal lobe. Increased conspicuity of smaller lesions on post-Gad.

Melanoma on medical Melanoma on medical imaging imaging

PET : PET :

Indicated for staging of known nodal disease, Indicated for staging of known nodal disease, in-transit diseasein-transit disease

Therapy responseTherapy response

Pre-operative assessment ( excluding mets)Pre-operative assessment ( excluding mets)

AB

82 year old male with right knee melanoma. A.Initial PET scan showing intensely FDG right knee lesion.B. progressive disease , cutaneous , subcutaneous and intramuscular mets.

67 year old male with resected lip, shoulder and scalp melanoma.

Also confirmed duodenojejunal junction melanoma. Brain mets found on staging PET

Course and prognosisCourse and prognosis

Curable if detected early. Usual presentations are Curable if detected early. Usual presentations are on extreme ends of spectrum. on extreme ends of spectrum.

Depends on :Thickness, ulceration, nodal Depends on :Thickness, ulceration, nodal involvement, metastasis.involvement, metastasis.

If up to 1mm thick , no ulceration and no nodal If up to 1mm thick , no ulceration and no nodal involvement : 95 %, 5 year survival .involvement : 95 %, 5 year survival .

If 4 mm and ulcerated: 45% 5yr survival If 4 mm and ulcerated: 45% 5yr survival

If ulcerated lesion & positive node: 24-29%If ulcerated lesion & positive node: 24-29%

Lung mets : 7% , 5 yr survival Lung mets : 7% , 5 yr survival

TreatmentTreatment

Surgery : wide local excision, Sentile node Surgery : wide local excision, Sentile node excision, brain mets ( symptomatic ) excision, brain mets ( symptomatic )

ChemotherapyChemotherapy

RadiotherapyRadiotherapy

References References

emedicine.comemedicine.com

Radiopedia.orgRadiopedia.org

Dermnetnz.orgDermnetnz.org