Skin Cancer 3 Flashcards
What are 75% of most cutaneous lymphomas?
T cell
What are cutaneous T cell lymphoma?
- Heterogenous group of neoplasms of skin-homing T-cells
2. show considerable variation in clinical presentation, histological appearance, immunophenotype and prognosis
What are the most common subtypes of cutaneous T cell lymphoma?
- Sezary syndrome
- Mycosis fungoides
What is the underlying molecular pathogenesis of CTCL?
- unknown
- inactivation of genes controlling cell cycle and apoptosis has been identified
What is the epidemiology of T cell lymphoma?
- Mycosis fungoides 0.4/100,000
- Typically older adults (median age of diagnosis 55-60)
- Sézary syndrome is rare - <5% of all CTCL
What is mycosis fungoides?
Common variant of primary CTCL and accounts for 50% of all primary cutaneous lymphoma
What does diagnosis of cutaneous T cell lymphoma require?
- Indolent clinical course
* Diagnosis requires skin biopsy
How long can diagnosis of mycosis fungiodes take?
- Diagnosis may take years as skin lesions may be present that are neither clinically nor histologically diagnostic for many years
- Atypical T-cell infiltrates may also be found in lymphomatoid drug eruptions
- Patches or plaques
What is the progression of mycosis fungiodes?
patch stage → plaque stage → (finally) tumour stage disease
years to decades
What is the duration of mycosis fungoides?
- Generally many years of nonspecific eczematous or psoriasiform skin lesions
- Median duration of onset of skin lesions to diagnosis of MF is 4-6 years, but may vary from several months to more than 5 decades
How is the early patch stage of mycosis fungoides characterised?
variably sized erythematous, finely scaling lesions which may be mildly pruritic
What is the pathogenesis of mycosis fungoides?
stepwise accumulation of genetic abnormalities → clonal proliferation → malignant transformation → progressive and widely disseminated disease
What are the molecular events in mycosis fungoides?
unidentified
What are the genetic abnormalities of Mycosis fungoides?
- P53, CDKN2A, PTEN, STAT3 identified in advanced MF, but not early
e. g. likely secondary genetic events - Persistent antigenic stimulation plays a crucial role in various lymphomas but no antigens known in MF
What evaluation and investigation is needed in mycosis fungoides?
- Type and extent of skin lesions
- Presence of palpable lymph nodes
- Skin biopsies
- Complete blood counts and serum chemistries
How do you treat the mycosis fungoides plaque/patch stage?
- topical corticosteroids
- phototherapy
- radiotherapy
When do you give systemic chemotherapy in mycosis fungoides?
-advanced stage when there is nodal or visceral involvement or in patients with rapidly progressive tumours unresponsive to less aggressive therapies
•Brentuximab vedotin (anti-30)
What are the 10 year survival rates in mycosis fungoides?
- > 95% in limited patch / plaque disease
- 85% in generalised patch / plaque disease
- 42% in tumour stage disease
- 20% in those with histological lymph node involvement
What are the differential diagnosis for mycosis fungoides?
- psoriasis
- eczema (discoid)
- parapsoriasis
What is the triad in sezary syndrome?
- Erythroderma
- Generalised lymphadenopathy
- Presence of neoplastic T-cells (Sézary cells) in the skin, lymph nodes and peripheral blood
What is sezary syndrome?
cutaneous T cell lymphoma
What is the criteria for diangosis of sezary syndrome?
- Demonstration of a T-cell clone in peripheral blood (eventhough skin) by molecular or cytogenetic methods
- Demonstration of immunophenotypical abnormalities an expanded CD4+ T-cell population – resulting in a CD4/ CD8 ratio of greater than 10 and / or aberrant expression of pan-T-cell antigens)
- An absolute Sézary cell count of at least 1000 cells per microlitre
What is the treatment of sezary syndrome?
- Systemic treatment is required
- Extracorporeal photophoresis
- Skin-directed therapies like PUVA or potent topical corticosteroids may be used as adjuvant therapy
What is kaposi sarcoma?
- HHV8
* Multifocal systemic disease
What can kaposi sarcoma look like?
- May be endemic or related to immunosuppression
* Cutaneous lesions can vary from pink patches to dark violet plaques, nodules or polyps
What is the treatment of kaposi sarcoma?
- chemotherapy (vincristine, doxorubicin, etoposide, bleomycin)
- and / or radiation is favoured over surgery
What is merkel cell carcinoma?
malignant proliferation of highly anaplastic cells which share structural and immunohistochemical features with various neuroectodermally derived cells, including Merkel cells
What is merkel cell carcinoma associated with?
80% are associated with polyomavirus
What is an aetiological factor for merkel cell carcinoma?
UV exposure
Where is merkel cell carcinoma?
predilection for the head and neck region of older adults
What does merkel cell carcinoma look like?
- solitary, rapidly growing nodule
- pink-red to violaceous, firm, dome shaped
- Ulceration can occur
Is merkel cell carcinoma aggressive?
- Aggressive, malignant behaviour
* >40% develop advanced disease
What is the treatment of merkel cell carcinoma?
- Treated with surgery, radiation therapy
- anti-PD1 (Pembrolizumab) / anti-PDL1 (Avelumab)
- checkpoint inhibitors when metastasis present
