Cutaneous T-cell lymphomas are a heterogeneous group of cutaneous non-Hodgkin's lymphomas,¹ the 2 most common forms of which are mycosis fungoides (MF) and Sézary syndrome (SS). The following sections discuss types, incidence, staging, and clinical phases of CTCL.

Types of CTCL
Incidence and Prevalence
Disease Staging
Clinical Phases of CTCL

Types of CTCL¹

Indolent CTCLs

Mycosis fungoides
MF variants and subtypes
Folliculotropic MF
Pagetoid reticulosis
Granulomatous slack skin
Subcutaneous panniculitis-like T-cell lymphoma
CD4+ small/medium pleomorphic T-cell lymphoma
CD30+ lymphoproliferative disorders
Anaplastic large cell lymphoma
Lymphomatoid papulosis

Aggressive CTCLs

Sézary syndrome
Cutaneous peripheral T-cell lymphoma, unspecified
Cutaneous aggressive CD8+ T-cell lymphoma
Cutaneous γ/δ T-cell lymphoma
Cutaneous NK/T-cell lymphoma, nasal type

Reference: 1. Willemze R, Jaffe ES, Burg G, et al. WHO-EORTC classification for cutaneous lymphomas. Blood. 2005;105:3768–3785.

Incidence and Prevalence

The incidence of CTCL in the United States is approximately 1,500 new cases per year.¹
The prevalence of CTCL in the United States ranges from 16,000 to 20,000 cases.²
In general, patients with T1 disease (the earliest skin lesions, such as patches covering <10% of the body surface area), have the longest survival. These patients survive longer than those with T2 disease with the same type of skin lesions covering ≥10% of the body surface area.
The prognosis for patients with skin tumors (T3 disease) is significantly worse than for patients with T1 or T2 disease. Survival is better for patients with skin tumors involving <10% of the body surface area than for those with ≥10% involved with tumors. As the skin lesions progress, the likelihood that the patient will develop lymph node involvement increases, and the chance for long-term survival worsens.^1,2

TNM Classification for CTCLs
Stage at Diagnosis³	Patients at Diagnosis, %³
T1: Patches/plaques covering <10% of body surface	42
T2: Patches/plaques covering ≥10% of body surface	30
T3: Tumor(s)	15
T4: Erythroderma	12

References: 1. Cutaneous Lymphoma Foundation. CTCL-MF fast facts. Available at: http://www.clfoundation.org/publications/publications.htm. Accessed February 14, 2007. 2. Lymphoma and Leukemia Society. Cutaneous T cell lymphoma. Available at: http://www.leukemia-lymphoma.org/all_mat_toc.adp?item_id=9846. Accessed February 14, 2007. 3. Habermann TM, Pittelkow MR. Cutaneous T-cell lymphoma and cutaneous B-cell lymphoma. In: Abeloff MD, Armitage JO, Niederhuber JE, Kastan MB, McKenna WG, eds. Clinical Oncology. 3rd ed. New York, NY: Churchill Livingstone; 2004:3077–3108.

Disease Staging

The information below the chart depicts the disease-specific survival by stage.

Stage¹	TNM Classification¹
IA	T1	N0	M0
IB	T2	N0	M0
IIA	T1-T2	N1	M0
IIB	T3	N0-N1	M0
III	T4	N0-N1	M0
IVA	T1-T4	N2-N3	M0
IVB	T1-T4	N0-N3	M1

TNM=primary tumor, regional lymph nodes, and distant metastasis; T=tumor size; N=nodes; M=metastasis.

In a study published by Kim and colleagues, the median survival by stage was²:

12.9 years for Stage IB/IIA
4.0 years for Stage IIB/III
1.5 years for Stage IV

References: 1. National Institutes of Health. Mycosis fungoides and the Sézary syndrome (PDQ®): treatment. National Cancer Institute. Available at: http://www.nci.nih.gov/
cancertopics/pdq/treatment/mycosisfungoides/HealthProfessional/page3. Accessed March 2, 2007. 2. Kim YM, Liu HL, Mraz-Gernhard S, Varghese A, Hoppe RT. Long-term outcome of 525 patients with mycosis fungoides and Sézary syndrome: clinical prognostic factors and risk for disease progression. Arch Dermatol. 2003;139:857–866.

Clinical Phases of CTCL

Patch

Tumor

Plaque

Erythroderma

These photos show the various stages of CTCL: patch, plaque, tumor, and erythroderma.

Patch: lesion of any size that does not have significant elevation or induration; may show pigment changes, scaling, crusting, or wrinkling
Plaque: lesion of any size that is elevated or indurated; may show pigment changes, scaling, crusting, or follicular prominence
Tumor: solid, nodular lesion >1 cm; may be ulcerated
Erythroderma: confluent erythematous lesions covering >80% of the body; may or may not include clinically significant blood involvement