| • | = neoplastic proliferations of T-lymphocytes that home to the skin |
| • | CTCL in which lesions evolve from patches into plaques and ultimately into tumors is termed mycoses fungoides |
the concept of a cutaneous T-cell:
| • | the diverse clinical entities that comprise CTCL can be grouped together because they are lymphomas of cutaneous T-cells (T-cells that hone to the skin; their job presumably is to patrol this organ) |
| • | cutaneous lymphocytes are CLA+ the ability to express CLA is presumably conferred on a lymphocyte during its activation in a draining lymph node by an antigen presenting cell that has migrated from inflamed skin |
| • | vast majority of CTCL = CD4+ T-cells |
| • | in leukemic CTCL, circulating malignant cells are CD45RO+, CLA+ |
clinical:
| • | tend to be distributed asymmetrically |
| • | predilection for area of skin that are protected by two layers of clothing such as the buttocks and breasts (girdle distribution) |
VARIATIONS (based on clinical appearance):
| • | clinical picture is dominated by a poikilodermatous appearance |
|
| • | AKA Woringer-Kolopp disease |
| • | characterized by prominent epidermotropism and a benign prognosis |
| • | some consider it to be a localized form of MF, whereas others argue it is a distinct clinicopathologic entity |
| • | presents as a solitary, slowly enlarging, erythematous, scaly plaque on an extremity |
| • | (or a group of lesions limited to one area, usually acral) |
| • | long duration and slow growth are characteristic |
| • | histology: many lymphocytes in the epidermis, reminiscent of Paget’s disease |
|
| • | a rare disorder most commonly found in Japan |
| • | characterized by pruritic flat-topped papules that spare the skin folds = the “deck chair sign” |
| • | considered a form of erythroderma in the elderly by some and a paraneoplastic syndrome by others |
| • | frequently there is an associated blood eosinophilia |
| • | histology – dense lymphohistiocytic infiltrate, eosinophils in papillary dermis |
| • | not enough cases have been reported to determine a true association with malignancies |
|
| • | a form of CTCL in which the lymphocytic infiltrate is associated with a granulomatous component and destruction of cutaneous elastic tissue |
| • | patients develop large regions of lax skin, especially in the axillae and groin |
|
| • | a variant of patch or early plaque stage MF that is seen in dark skinned patients |
| • | patients respond to therapy by repigmenting |
| • | relapse is often heralded by a return of hypopigmentation |
|
Sezary syndrome – best applied to patients with leukocytosis and Sezary cells
erythrodermic CTCL – a broader term that encompasses all stages of erythrodermic and leukemic disease (whether or not Sezary cells are identified in the blood)
| • | Pautrier’s microabscesses = a tightly packed cluster of lymphocytes in the epidermis surrounded by a clear space; a fairly specific finding, though not present in the majority of biopsies |
| • | histology may vary with type of lesion: |
| • | patch and plaque – cyologic atypia not striking; band-like infiltrate unassociated with vacuolar alteration; epidermotropism without spongiosis |
| • | tumor stage – nearly always have striking nuclear atypia; less epidermotropism (suggesting that the malignant t-cells are less dependent on the epidermal microenvironment for growth) |
|
TREATMENT (for patch and plaque stage):
| • | works by delivering a lymphocyte-toxic mustard chemotherapy to the entire skin – the domain of the cutaneous lymphocyte |
| • | cutaneous lymphocytes are re-circulating through the skin, the proliferative rates of the malignant cells are low enough to require long term treatment to therapeutically reduce their numbers ( = principle behind maintenance treatment) |
| • | apply nightly to whole body surface until remission, then QOD X 6months, then Qweek X 1 year |
| • | hypersensitivity and primary irritant reactions |
| • | hypo- and hyperpigmentation |
| • | second cutaneous malignancies |
|
| • | applied to total skin QD until the inevitable irritant reaction occurs, or for a maximum of 6 to 8 weeks |
| • | in general, one achieves a remission within a few weeks |
| • | advantages over nitrogen mustard: shorter treatment course |
| • | contact hypersensitivity (10%); severe erythema (35%); post-treatment telangiectasia (35%) |
| • | mild bone marrow suppression (30%), therefore monitor CBC |
|
| • | TIW until mostly clear; then BIW until complete remission |
| • | then Qweek X 1year; then QOweek X 2 years (d/c after 5 years of remission) |
|
| • | because electrons penetrate only to the dermis, electron beam therapy may be used without systemic effects |
| • | local side effects minimized when total dose is highly fractionated |
| • | as total dose increases, so does risk of SCC and radiodermatitis |
|
| • | extracorporeal photochemotherapy |
| • | DAB-IL2 (diphtheria A toxin interleukin 2 gene fusion product) |
| • | methotrexate, etoposide, fludarabine monophosphate, interferon |
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