Table 3: Summary of etiopathogenesis and characteristic clinical features of primary cutaneous B-cell lymphoma variants.

 

PCDLBCL-LT

PCFCL

PCMZL

Epidemiology

 

- 20% of all primary B-cell lymphomas

- seventh decade

- female predominance [11]

- 60% of all primary B-cell lymphomas

- fifth decade

- male predominance[3]

- fifth and sixth decades

- male predominance

[12]

Pathogenesis

- no identifiable risk factors or hereditary tendencies [13]

- MYC, BCL6, IGH, MALT1, CDKN2A/2B, PDL1/2, FOXP1, PAX5, PIM1, MYD88, CARD11, CD79B, and TNFAIP3/A20 mutations [10, 13]

- Borrelia burgdorferi [6]

Clinical

- violaceous papules, plaques, or nodule(s) +/- ulceration

- multifocal

- 80% leg involvement

- aggressive

- high relapse rate, in general

- 60% extracutaneous dissemination

[1,3,11]

- violaceous papules, plaques, or nodule(s) +/- ulceration

- 75% solitary

- head/scalp > trunk

- 5% on the legs

- indolent

- 10% extracutaneous dissemination

[1,3]

- violaceous papules, plaques, or nodule(s) +/- ulceration

- 50% solitary

- trunk > arms

- indolent

- higher relapse rate if multiple skin lesions present

- extracutaneous dissemination rare

[1,3,12]

First-line therapy [4]

Polychemotherapy

Radiotherapy, surgery

Radiotherapy, surgery

Additional therapies [4]

- Radiotherapy, surgery

- Monoclonal antibodies

- Lenalidomide

- Ibrutinib

Polychemotherapy

Polychemotherapy

Prognosis

5-year overall survival, 50-60% [1]

5-year overall survival, 95% [1]

5-year overall survival, 97% [8]

PCDLBCL-LT: primary cutaneous diffuse large B cell lymphoma- leg type; PCFCL: primary cutaneous follicle center lymphoma; PCMZL: primary cutaneous marginal zone lymphoma; MYC: proto-oncogene; BCL6: B-cell lymphoma 6; IGH: Immunoglobulin heavy locus; MALT1: Mucosa-associated lymphoid tissue lymphoma translocation protein 1; CDKN2A/2B: cyclin-dependent kinase inhibitor 2A/2B, PDL1/2: programmed death‐1/2; FOXP1: Forkhead box P; PAX5: Paired Box 5; PIM1: proto-oncogene and serine/threonine kinase; MYD88: Myeloid differentiation primary response protein; CARD11: Caspase recruitment domain-containing protein 11; CD79B: Cluster of differentiation 79B; TNFAIP3/A20: Tumor necrosis factor, alpha-induced protein 3 or A20; Polychemotherapy, e.g. rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone.