Radiation Oncology/Melanoma/Staging

Melanoma Staging Clark Levels Level I - Confined to epidermis (in situ); not an invasive lesion Level II - Invasion of papillary dermis; invasion past basement membrane Level III - Papillary dermis filled by tumor and reticular dermis compressed, but not invaded Level IV - Invasion of reticular dermis; subcutaneous tissue not involved Level V - Invasion of subcutaneous tissue Univ Pennsylvania; 1989 2593166 -- "Model predicting survival in stage I melanoma based on tumor progression." (Clark WH Jr, J Natl Cancer Inst. 1989 Dec 20;81(24):1893-904.) Prognostic model for primary, clinical Stage I cutaneous melanoma. Clark levels defined Current staging AJCC 7th Edition (2009) Primary Tumor: (Based on thickness, not level of invasion) Tis - melanoma in situ (epidermis only) T1 - <= 1.0 mm in thickness T1a - no ulceration; mitotic rate < 1/mm2 T1b - with ulceration or mitotic rate >= 1/mm2 T2 - 1.01 - 2 mm in thickness T2a - no ulceration T2b - with ulceration T3 - 2.01 - 4 mm in thickness T3a - no ulceration T3b - with ulceration T4 - > 4 mm in thickness T4a - no ulceration T4b - with ulceration Regional Lymph Nodes: N0 - no nodes N1 - 1 positive lymph node N1a - micrometastasis N1b - macrometastasis N2 - 2-3 nodes or intralymphatic regional metastasis without nodal metastasis N2a - micrometastasis N2b - macrometastasis N2c - satellite or in-transit metastasis without nodal metastasis N3 - 4 or more nodes, or matted metastatic nodes, or satellite/in-transit metastases with nodal mets Satellite metastases: defined as grossly visible cutaneous or subcutaneous intralymphatic metastases occurring within 2 cm of primary melanoma Microsatellites: any discontinuous nest of intralymphatic metastatic cells >0.05 mm in diameter that are clearly separated from the main invasive lesion by a distance of at least 0.3 mm In-transit metastases: grossly visible cutaneous or subcutaneous intralymphatic metastases more than 2 cm from primary melanoma but before the first echelon of regional lymph nodes Distant Metastases: M1a - metastasis to skin, subcutaneous tissues, or distant lymph nodes M1b - metastasis to lung M1c - all other visceral sites, or mets to any site with elevated LDH Clinical Stage Grouping: Clinical staging is based on information from excision of the melanoma and clinical evaluation for distant metastatic disease but does not include lymphadenectomy 0 - Tis IA - T1a N0 IB - T2a or T1b N0 IIA - T3a or T2b N0 IIB - T4a or T3b N0 IIC - T4b N0 III - Any N+ IV - Any M1 Note: ulceration (b) upstages by one grouping Pathologic Stage Grouping: Includes information obtained from lymphadenectomy Same as clinical staging except for Stage III IIIA - N1a or N2a (micrometastasis), no ulceration (T1-4a) IIIB - N1b or N2b or N2c (micromets or satellite), no ulceration (T1-4a); N1a or N2a (micromets), with ulceration (T1-4b) IIIC - N1b or N2b or N2c (micromets or satellite), with ulceration (T1-4b); or any N3 Changes from 6th Edition: T-stage: T1a vs T1b now includes mitotic rate in addition to ulceration; eliminated use of Clark level. T2-T4 unchanged. No changes in N-stage or M-stage No changes in Stages I or II. No changes in Clinical Stage III For Pathologic Stage III, N2c with ulceration reclassified from IIIB to IIIC Older staging systems AJCC 6th Edition (2002) T-stage: (Based on thickness, not level of invasion, except for T1 melanomas) Tis - melanoma in situ (epidermis only) T1 - <= 1.0 mm in thickness T1a - Clark level II or III, no ulceration T1b - Clark level IV or IV or with ulceration T2 - 1.01 - 2 mm in thickness T2a - no ulceration T2b - with ulceration T3 - 2.01 - 4 mm in thickness T3a - no ulceration T3b - with ulceration T4 - > 4 mm in thickness T4a - no ulceration T4b - with ulceration N-stage: N0 - no nodes N1 - 1 positive lymph node N1a - clinically occult (microscopic) N1b - clinically apparent (macroscopic) N2 - 2-3 nodes or intralymphatic regional metastasis without nodal metastasis N2a - microscopic N2b - macroscopic N2c - satellite or in-transit metastasis without nodal metastasis N3 - 4 or more nodes, or matted metastatic nodes, or satellite/in-transit metastases with nodal mets M-stage: M1a - metastasis to skin, subcutaneous tissues, or distant lymph nodes M1b - metastasis to lung M1c - all other visceral sites, or mets to any site with elevated LDH Clinical stage grouping: Clinical staging is based on information from excision of the melanoma and clinical evaluation for distant metastatic disease but does not include lymphadenectomy 0 - Tis IA - T1a N0 IB - T2a or T1b N0 IIA - T3a or T2b N0 IIB - T4a or T3b N0 IIC - T4b N0 III - Any N+ IV - Any M1 Note: ulceration (b) upstages by one grouping Pathologic stage grouping: Includes information obtained from lymphadenectomy Same as clinical staging except for Stage III IIIA - N1a or N2a, no ulceration (T1-4a) IIIB - N1b or N2b, no ulceration (T1-4a); N1a or N2a, with ulceration (T1-4b); or any N2c IIIC - N1b or N2b, with ulceration (T1-4b); or any N3 Satellite metastases: defined as intralymphatic metastases occurring within 2 cm of primary melanoma In-transit metastases: more than 2 cm from primary melanoma but before the first echelon of regional lymph nodes AJCC 5th edition (1997) T stage was based primary on Clark level of invasion. Used Breslow thickness as a secondary prognostic factor: with different thresholds of 0.75, 1.5, and 4 mm. Did not include ulceration. Satellite mets were in the T-stage. Thick (>4mm) melanomas were Stage III, not IIC. For N-stage used size not number of mets. Did not use microscopic vs macroscopic. Did not have separate M stage for lung mets. Did not use LDH. Survival 10-year OS: (estimated from graph, AJCC staging manual) Stage IA: 90%, IB: 80% Stage IIA: 65%, IIB: 50%, IIC: 35% Stage III: 35% Stage IV: < 10%