Case 4 -

Cutaneous EBV-Associated Lymphoproliferative Disorder Soon Bahrami University of Louisville School of Medicine Louisville, KY

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Clinical History: The patient is a 15 year-old female with a 7 year history of ulcerative colitis who presents with an enlarging painful lesion of the left lower eyelid. The lesion developed 3 weeks prior to presentation as a small red papule which the patient thought occurred following discovery of "a spider in her bed". Her ulcerative colitis is well controlled by azathioprine and 6-mercaptopurine (6-MP). Six weeks prior to presentation the patient had mononucleosis as confirmed by symptoms and a positive heterophil antibody test. Physical examination revealed a 3cm indurated tumor of the left lower eyelid that had a violaceous hue. Case 4 - Slide 1 Click to view with ImageScope Click to view with a Web-Based Viewer Case 4 - Figure 1 Scanning power shows a dense nodular infiltrate of small blue cells throughout the biopsy specimen. Case 4 - Figure 2 Closer view confirms the nodular architecture and cells appear to be lymphoid. Case 4 - Figure 3 Lymphocytes consist of a small to medium size population. Case 4 - Figure 4 Lymphocytes are infiltrating in and around skeletal muscle. Case 4 - Figure 5 Atypical and plasmacytoid forms are noted. Case 4 - Figure 6 Another view of atypical and plasmacytoid forms. Case 4 - Figure 7 - CD3 CD3 highlights small admixed lymphocytes. Case 4 - Figure 8 - CD20 CD20 highlights most of the infiltrate including atypical lymphocytes. Case 4 - Figure 9 - EBER In-situ hybridization reveals nuclear positivity for EBER in many of the large atypical lymphocytes. Biopsy Findings: Sections demonstrate a dense nodular dermal lymphoid infiltrate of small and large lymphocytes that extend to and infiltrate throughout the skeletal muscle at the base of the biopsy. The epidermis is spared. Cytologically, large round atypical lymphoid cells containing prominent nucleoli are noted. Some cells have a plasmacytoid appearance. Other inflammatory cell types are inconspicuous. Diagnostic Considerations and Ancillary Studies: In this case as in most cases of dense lymphoid infiltrates, the main diagnostic issue is to determine whether the population represents a benign/reactive lymphoid infiltrate or a lymphoma. Diagnostic considerations may include both B and T cell lymphomas, leukemia cutis, lymphocytoma cutis, lymphomatoid drug reactions, persistent nodular arthropod bite reactions, and an inflammatory stage of a connective tissue disorder. Table 1 lists clinical and pathologic features that may aid in sorting out this differential diagnosis in a pediatric population. However, in our patient we have clinical information that quickly narrows the differential diagnosis; the presence of a recent EBV infection in the setting of immunosuppression makes a diagnosis of EBV associated lymphoproliferative disorder highly likely. This underscores the importance of clinical history when dealing with an "atypical lymphoid infiltrate" under the microscope! Furthermore, it allows you to choose a directed immunohistochemical panel to confirm your clinicopathologic impression. In this case, many of the lymphoid cells including larger atypical forms were positive for CD20 and EBER (in situ hybridization). Weak and focal CD30 positivity was seen in some of these cells. Additionally, CD3 highlighted a significant number of admixed small lymphocytes that were composed of both CD4 and CD8 positive subsets. Plasmacytoid forms labeled with CD79a. Pertinent negative stains included TdT, CD10, and BCL-2. Unfortunately, tissue was not available for clonality studies. However, with the highly suggestive clinical presentation and supportive histopathologic and immunohistochemical evaluation, a diagnosis of EBV-associated lymphoproliferative disorder was made. Table 1. Differential Diagnostic Considerations Diagnosis Clinical Pathology Ancillary Techniques Lympho-blastic lymphoma/leukemia Children and young adults Single nodule in head and neck region B-cell disease more common in cutaneous disease Grenz zone Small to medium sized monotonous infiltrate of lymphoblasts Lacks stromal or inflammatory response IPox (B): +TdT, CD43, CD99, CD19, CD10**CD45 may be - IPox (T): +TdT, CD43, CD99Usually CD7+Variable CD1a, CD2, CD3, CD4, CD5, CD8, CD10 BM/peripheral blood Myeloid Leukemia Cutis Much more frequently in adults; predisposition in children with Downs, Ataxia telangiectasia, Bloom, Fanconi, and Kostmann syndrome Solitary to multiple papules, nodules, and plaques on scalp, face, trunk, extremities; gingival hyperplasia Skin involvement MC with Acute myelomonocytic or monoblastic/monocytic type Grenz zone Single filing of atypical cells between collagen bundles (cell mixture dependent on underlying leukemia Periadnexal accentuation IPox: + lysozyme, MPO, CD45, CD43, CD74Variable CD68, CD34, chloracetate esterase BM/peripheral blood Burkitt Lymphoma Three clinical variants: (1) Endemic: Africa, children, EBV relatedJaw and orbit (2) Sporadic: worldwide, children and young adultsAbdominal mass, bilateral breast involvement (3) Immunodeficiency Associated: primarily with HIV, EBV in 25-40%Nodal and BM involvement Diffuse monotonous pattern of medium sized cells w/ multiple prominent central nucleoli; deeply basophilic cytoplasm; squared off borders (retraction artifact) Starry sky pattern IPox: + CD19, CD20, CD10, BCL6 CD5, TdT neg. **Ki-67 marks almost 100% of the cells MYC translocationt(8;14), t(2;8), t(8;22) Lympho-cytoma Cutis MC association w/ Borrelia burgdorferi; very common in children located in endemic regions Females > Males Firm solitary red-brown nodule or tumor Earlobe, nipple, scrotum pathognomonic sites Dense, nodular mixed cell infiltrates that may be top heavy but are more commonly diffuse Reactive germinal centers Plasma cells and eosinophils Polyclonal immunoglobulin light chains Serum antibodies or PCR for Borrelia Lympho-matoid Drug Rxn Many drugs can cause but anticonvulsants (hydantoins) common culprit May have generalized B type symptoms Edema of face and erythematous pruritic macules, papules, nodules Can simulate T or B cell pattern including mycosis fungoides, follicular lymphoma, MZL, CD30+ LPD Polyclonal immunoglobulin light chains Regress with removal of drug Persistent Nodular Arthropod Bite Rxn Nodular scabies MC Round to oval bright red nodules especially in genitalia, axilla, elbows May be persistent for months Mite rarely identified Dense superficial and deep nodular infiltrates of lymphohistiocytic character with scattered atypical large lymphocytes Admixed plasma cells and eosinophils Prominent vessels with reactive endothelial hyperplasia almost always found Polyclonal immunoglobulin light chains Predominantly a T cell infiltrate **Beware that large atypical lymphs may be CD30+. Pitfall for LyP. **Another caveat: a persistent arthropod bite reaction in the elderly population may indicate CLL. CTD's Inflammatory phase of morphea and scleroderma Lymphocytic infiltrate of Jessner Can demonstrate dense nodular infiltrates Correlation with clinical findings usually sufficient for diagnosis Topic Discussion: It is well known that the incidence of lymphoproliferative disease (LPD) is higher in immunosuppressed individuals than in the general population; this immunosuppression may be acquired, congenital, or iatrogenically induced. It is convenient to refer to this group of disorders as immunodeficiency/immunosuppression-related lymphoproliferative disorders (IR-LPD). This is a clinically and pathologically heterogeneous group of disorders. One of the most commonly encountered and best investigated subsets are those IR-LPDs that occur in the setting of solid organ and bone marrow transplantation, and this subset is referred to as post-transplant lymphoproliferative disorders (PTLDs). They occur in approximately 1% of renal transplants and up to 10% of heart and combined heart/lung transplants under various immunosuppressive agents. They have been well classified according to clinical, pathological, and molecular parameters as described in Table 2, and they represent a spectrum of lesions between reactive proliferations and true lymphomas. They frequently occur in extranodal sites such as the lung, gastrointestinal tract, CNS, and the allograft in addition to presentation in lymph nodes. Children and young adults are frequently affected. The disease may arise months to many years following transplantation, and interval to presentation is dependent on various factors including immunosuppressive agent, type of transplant, and EBV status of the tissue with positive cases presenting sooner than negative cases. Epstein Barr virus has been strongly implicated in the pathogenesis of these disorders. It is thought that usual T-cell immune surveillance keeping a latent EBV infection in check is compromised by the state of immunosuppression allowing proliferation and transformation of lymphoid cells harboring viral genomic material. Table 2. Categories and Features of PTLD Category Histopathologic Features Clonality Oncogene and/or Tumor Suppressor Alterations Clinical Course/Outcome Reactive plasmacytic hyperplasia/IM-like Normal architecture retained Mixture of lymphs, plasma cells, rare immunoblasts Minimal cytologic atypia Usually polyclonal None Regression with reduction/removal of immunosuppression Polymorphic PTLD Normal architecture disrupted Mixture of lymphs, plasmacytoid lymphs, immunoblasts Necrosis variable Cytologic atypia variable Clonal None Partial to complete regression with reduction/removal of immunosuppression OR Resolution with surgery and radiation or chemotherapy OR Progression despite therapy Monomorphic PTLD-subclassified according to lymphoma classification* Disruption of normal architecture Cytologically malignant cells with large transformed blastic appearing cells Plasmacytic forms may be seen Clonal Present Aggressive disease course; many result in death despite treatment *B-cell neoplasms include DLBCL, Burkitt lymphoma, Plasma cell myeloma, Plasmacytoma-like lesions. T-cell neoplasms generally refer to Peripheral T-cell lymphoma NOS though other types are recognized. The WHO classification recognizes Hodgkin lymphoma and Hodgkin lymphoma-like PTLD as a fourth category. Another interesting subset of IR-LPDs is methotrexate-associated LPDs which occur in the setting of methotrexate therapy for autoimmune disease; most commonly this is seen in rheumatoid arthritis but has also been described in psoriasis and dermatomyositis. Reported cases morphologically represent diffuse large B-cell lymphoma (35%), Hodgkin lymphoma (25%), Hodgkin-like lymphoma (8%), polymorphous PTLD-like lymphoproliferative disorder (14%) in addition to a small number of other morphologies (follicular lymphoma, Burkitt lymphoma, and peripheral T-cell lymphomas). Many of these cases occur in extranodal locations including the gastrointestinal tract, skin, lung, kidney, and soft tissue. EBV has also been implicated in this subset and positivity varies dependent on the morphologic type: Hodgkin and Hodgkin-like >> PTLD-like and DLBCL. Cessation of methotrexate therapy leads to regression in many of the cases; this is found to be especially representative in those cases that are EBV+. Immunophenotypic evaluation variably depends on the category of LPD that one is dealing with. In plasmacytic hyperplasias there is an admixture of polyclonal B cells, plasma cells, and T cells. Immunoblasts will be EBV+. Polymorphic LPD will show similar findings or may have monotypic surface and cytoplasmic Ig. EBV positivity is found in the majority of cases. Monomorphic LPDs will phenotype as CD19, CD20, and CD79a in B-cell cases with demonstration of monotypic Ig in 50% of cases. Antigens usually associated with T cells, namely CD43 and CD45RO may be expressed. CD30 is found in some cases, regardless of the presence or absence of anaplastic morphology. EBV is expressed in the majority of cases. Monomorphic T-cell LPDs are recognized by pan T cell antigen expression and depending on the type of lymphoma may express CD4, CD8, CD56, or CD30. Either αβ or γδ T-cell receptors are present. EBV positivity is much less frequent in this subset. In general, monomorphic LPDs will immunophenotype as to the category of lymphoma that is represented. Cutaneous presentation of IR-LPDs has been described, though it is rare and usually in the setting of multi-system involvement. Less than 100 reported cases are found in the literature. A recent case-series by Wallet-Farber et al reviewed 68 cases of IR-LPDs that had reported cutaneous involvement, the great majority of which had other organ involvement also. Of these, 45 were of B-cell type and 23 were T-cell type. Clinical presentations are diverse with single or multiple skin lesions that may include nodules, plaques, and ulcerative lesions. In the B-cell subset, most LPDs are EBV +, however, this is in contrast to T-cell LPDs where EBV was positive in only 4 of the 17 tested cases in the literature. T-cell cutaneous LPDs span a spectrum of CD30+ ALCL, mycosis fungoides, subcutaneous panniculitic T-cell lymphoma and others. They also found that B-cell LPDs had a much more favorable prognosis than T-cell LPDs. Furthermore, those cases presenting with disease limited to the skin tend to have a benign course; most cases resolve with reduction or removal of immunosuppression. More recently there have been a few reports of IR-LPDs in the setting of immunosuppression related to inflammatory bowel disease. Commonly implicated immunosuppressive agents include azathioprine and 6-mercaptopurine. All reported cases thus far have been nodal or extranodal disease (mostly gastrointestinal) without cutaneous manifestations, though soft tissue involvement has been described. The current illustrative case demonstrates that these inflammatory bowel related LPDs can also present with cutaneous involvement. Since we had the presence of architectural distortion in addition to an admixture of cell types, I favor this case represents a form of polymorphic LPD. As in the aforementioned subsets of IR-LPDs, EBV is implicated in many of previously described cases as it was in our case. The clinical course is variable but often shows regression with decreased or removed immunosuppression, and this was the case in the example presented. It is important for the pathologist/dermatopathologist to recognize IR-LPDs for a number of reasons: Numerous settings of immunosuppression in which LPDs can occur are recognized and include: Post-transplant LPDs Methotrexate-associated LPDs HIV-associated LPDs Congenital immune deficiency-associated LPDs Iatrogenically induced immune deficiency-associated LPDs to include recent descriptions of chronic immunosuppression in cases of inflammatory bowel disease These cases are more frequently being reported as manifesting with cutaneous involvement which is readily visible and detectable by clinical exam lending itself to biopsy and pathologic evaluation. Evaluation for EBV should be performed in the "atypical lymphoid infiltrate" found in a setting of immune suppression. Testing is readily available. EBER detection by in-situ hybridization is thought to be most sensitive. Recognition will allow for more conservative treatment and patient reassurance in those cases of hyperplasias and polymorphic LPDs. Selected References: Harris NL, Swerdlow SH, Frizzera G, Knowles DM. Post-transplant lymphoproliferative disorders. In: Jaffe ES, Harris NL, Stein H, Vardiman JW, editors. Pathology and genetics. Tumors of hematopoietic and lymphoid tissues. Lyon: IARC Press;2001. pp. 264-269. Harris NL, Swerdlow SH. Methotrexate-associated lymphoproliferative disorders. In: Jaffe ES, Harris NL, Stein H, Vardiman JW, editors. Pathology and genetics. Tumors of hematopoietic and lymphoid tissues. Lyon: IARC Press;2001. pp. 270-271 . Wallet-Faber N, Bodemer C, Blanche S, et al. Primary cutaneous Epstein-Barr virus-related lymphoproliferative disorders in 4 immunosuppressed children. J Am Acad Dermatol. 2008;58:74-80. Knowles DM. Immunodeficiency-associated lymphoproliferative disorders. Mod Pathol. 1999;12:200-217. Chai C, White WL, Shea CR, Prieto VG. Epstein Barr virus-associated lymphoproliferative-disorders primarily involving the skin. J Cutan Pathol. 1999;26:242-247. Clarke LE, Junkins-Hopkins J, Seykora JT, Adler DJ, Elenitsas R. Methotrexate-associated lymphoproliferative disorder in a patient with rheumatoid arthritis presenting in the skin. J Am Acad Dermatol. 2007;56:686-690. Capaldi L, Robinson-Bostom L, Kerr P, Gohh R. Localized cutaneous posttransplant Epstein-Barr virus-associated lymphoproliferative disorder. J Am Acad Dermatol. 2004;51:778-780. Verma S, Frambach GE, Seilstad KH, Nuovo G, Porcu P, Magro CM. Epstein-Barr virus-associated B-cell lymphoma in the setting of iatrogenic immune dysregulation presenting initially in the skin. J Cutan Pathol. 2005;32:474-483. Dayharsh GA, Loftus EV, Sandborn WJ, et al. Epstein-Barr virus-positive lymphoma in patients with inflammatory bowel disease treated with azathioprine or 6-mercaptopurine. Gastroenterology. 2002;122:72-77. Losco A, Gianelli U, Cassani B, Baldini L, Conte D, Basilisco G. Epstein-Barr virus-associated lymphoma in Crohn's disease. Inflamm Bowel Dis. 2004;10:425-429.