Page 1540 - Hematology_ Basic Principles and Practice ( PDFDrive )

Chapter 85 T-Cell Lymphomas 1367

Histopathologic evaluation demonstrates that infiltrates are nonepi- of cutaneous γδ T-cell lymphoma. Patients often present with a high
dermotropic, with variable numbers of medium-sized to large pleo- level of LDH and constitutional symptoms and succumb to the
morphic T cells with or without cerebriform nuclei and immunoblasts. disease, often associated with hemophagocytic syndrome. For the
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The tumor cells are CD4 , with CD30 expression restricted to a few most part, all therapies have shown modest effectiveness. Sustained
scattered tumor cells. The infiltrate is often accompanied by a mixed remissions have not resulted from radiation, immune therapy, or
infiltrate with reactive B cells and granulomatous or histiocytic multiagent chemotherapy. However, a case with CR for 23 months
component. Multiagent chemotherapy is used in most instances, with following aSCT has been reported. Cytotoxic features such as
radiation therapy reserved for patients with localized disease. The necrosis, hemorrhage, and vasculitis are commonly encountered. The
5-year survival rate is less than 20%. immunophenotype is characterized by CD4/CD8 double negativity
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(with some CD8 cases), lack of CD5 expression, and expression of
Pleomorphic Small- or Medium-Sized Cutaneous cytotoxic granules.
T-Cell Lymphoma
Primary Cutaneous Aggressive Epidermotropic CD8
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Pleomorphic small- or medium-sized CTCL is a rare entity. Patients T-Cell Lymphoma
typically present with a single red-purplish nodule or tumor involving
the head and neck regions. Rarely are multiple nodules noted. The This extremely rare condition, formerly known as generalized pagetoid
neoplastic cells are accompanied by many reactive B cells and histio- reticulosis or Ketron-Goodman syndrome, constitutes less than 1% of
cytes, which has led to the hypothesis that they may arise from a all cutaneous lymphomas. The term Berti lymphoma is often used to
follicular T-helper cell population expressing BCL6, PD-1, and refer to this condition. Men are affected more commonly, and patients
CD10. Typically, CD30 is negative, and CD4 expression is strong. present with extensive erosive patches with frequent mucosal involve-
TCR should be positive. In our opinion, cases presenting with a ment. Occasionally the lesions are exophytic and hemorrhagic,
single lesion should not be diagnosed as having lymphoma; despite resembling pyogenic granuloma. The course is invariable and rapidly
its clonal nature, the prognosis is invariably benign. These lesions fatal with exceptional cases reported surviving following ASCT.
were called pseudolymphomas in the past without significant conse- Histologically the infiltrate is markedly epidermotropic and adnexo-
quences. However, patients presenting with multiple lesions are part tropic, infiltrating into hair follicles and sweat glands, eventually
of the d’emblée presentation and should be approached more aggres- becoming hemorrhagic and ulcerated. The cells are also of intermedi-
sively, including full staging and systemic therapy. Patients with more ate size, always expressing CD8 as well as other T-cell markers such
generalized disease have been treated with regimens used for indolent as CD7 and CD45RO.
NHLs. Five-year survival rates are 100% in unilesional cases and
exceed 60% in patients with more extensive disease.
Extranasal Natural Killer/T-Cell Lymphoma
Subcutaneous Panniculitis-Like T-Cell Lymphoma EBV-induced extranasal NKTCLs rarely appear in the skin as the
initial site of presentation. This condition is mostly reported in Asia
Subcutaneous panniculitis-like T-cell lymphoma is a rare entity. and Latin America with rare cases seen in the United States. Although
Patients, typically younger and female, present with asymptomatic occasional cases remain localized in the skin, most of these lympho-
deep subcutaneous nonulcerated nodules and plaques involving the mas eventually involve other sites such as the testes or the gastro-
legs. Systemic symptoms are common, including fevers, fatigue, and intestinal tract. A careful ear, nose, and throat evaluation to rule out
anorexia. Overlapping or preceding signs of systemic lupus erythe- nasopharyngeal involvement is important. The lesions are mostly
matosus or other autoimmune conditions are commonly observed. large ulcerated tumor lesions with hemorrhagic and necrotic appear-
Histopathologic examination reveals a subcutaneous infiltrate with ance. Histologically the tumor is composed of a deep infiltrate with
pleomorphic medium-sized T cells mixed with a reactive lymphoid intermediate-sized lymphocytes with cytotoxic changes, hemorrhage,
infiltrate and some histiocytes. Tumor cell necrosis, karyorrhexis, and and necrotic debris. A histologic landmark is the presence of angio-
erythrophagocytosis are common findings. Differential diagnosis centric and angiodestructive features. The immunophenotype is
includes the frequently fatal but nonneoplastic cytophagic histiocytic characterized by the expression of CD3ε in the cytoplasmic mem-
panniculitis. Neoplastic infiltration of deep blood vessels can be noted brane, as well as CD56. Cytotoxic cytoplasmic granules are always
in some cases. Immunophenotyping reveals postthymic T-cell markers identified, and EBV in the tumor cells can be demonstrated by the
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with a CD8 phenotype and expression of cytotoxic markers such as expression of EBER or LMP1. A lymphoproliferative disorder resem-
TIA-1 and granzyme B. By definition the tumor cells are negative for bling hydroa vacciniforme has been reported almost exclusively in
EBV markers and lack expression of the γδ heterodimer. However, Latin America, especially in the Andes region, where the combination
T-cell clonality including the γ- or β-gene is commonly identified. of high altitude with intense ultraviolet rays triggers this process,
The prognosis is fairly good, with a 5-year survival rate over 80% which is mostly seen in vulnerable indigenous patients. These patients
with the exception of patients with a concurrent hemophagocytic present with facial edema, hepatosplenomegaly, and necrotizing
syndrome (fevers, cytopenias). Cases in which the panniculitic find- hemorrhagic lesions triggered by sun exposure or an arthropod bite
ings coexist with systemic lupus erythematosus may behave in a reactions. These conditions are associated with a very aggressive clini-
clinically indolent fashion. cal course and patients often succumb to hemophagocytic syndrome.
Multiagent chemotherapy has not been effective, and perhaps the
only hope for these individuals is an ASCT.
Primary Cutaneous γδ-T-Cell Lymphoma

Cutaneous γδ T-cell lymphoma is a rare condition that tends to Lymphomatoid Granulomatosis
present with extensive panniculitis-like plaques on the extremities
with a tendency to ulcerate during the course of the disease. A subset Lymphomatoid granulomatosis is a rare multiorgan disease of the
of patients present with single lesions resembling an infectious process lungs, nasopharynx, joints, and peripheral and central nervous
or with extensive chronic erythematous and scaly patches resem- systems. Cutaneous involvement occurs in 25%–50% of patients.
bling MF. Several of our patients had comorbidities associated with Although nodules are most common, some patients have nonspecific
immune suppression, including autoimmune conditions or other macules, papules, or ulceration. Histologic evaluation reveals an
lymphoproliferative conditions or malignancies. Chronic antigen angiocentric, polymorphous infiltrate of atypical lymphocytes and
stimulation has been hypothesized to play a role in the pathogenesis histiocytes surrounding and invading blood vessels within the dermis.