Skin - Merkle

Question 1

Merkel cell T staging

Answer 1

T1: </= 2 cm
T2: > 2 but </= 5 cm
T3: > 5 cm
T4: invades fascia, muscle, cartilage or bone

Question 2

Merkel cell clinical N staging

Answer 2

N1: metastasis in regional lymph node(s)
N2: In-transit mets WITHOUT lymph node mets
N3: In-transit AND nodal mets

Question 3

Merkel cell pathologic N staging

Answer 3

N1: metastasis in regional lymph node(s)
N1a(sn): sentinel biopsy detected
N1a: clinically occult, detected on dissection
N1b: clinically detected
N2: In-transit mets WITHOUT lymph node mets
N3: In-transit AND nodal mets

Question 4

Merkel cell M staging

Answer 4

M1a: Mets to distant skin/subcu tissue or nodes
M1b: mets to lung
M1c: mets to all other visceral sites

Question 5

Merkel cell treatment paradigm if resectable

Answer 5

Surgery -> RT for + margins, + nodes/ENE, tumor > 1 cm, solid organ transplant or other immunosuppression, HIV, CLL, head and neck primary, LVI +

Question 6

Merkel cell: Follow-up after definitive treatment

Answer 6

Exam, complete skin and nodes every 3-6 months for 3 years then 6-12 mo thereafter

Question 7

Merkel cell: RT dosing

Answer 7

Adjuvant: negative margins 50-56 Gy, mic + 56-60 Gy, gross disease 60-66 Gy
Unresectable: 60-66 Gy

Question 8

Merkel cell: RT margins

Answer 8

5 cm