Lymphomatoid Papulosis Workup

Updated: Oct 15, 2020
  • Author: John A Zic, MD; Chief Editor: William D James, MD  more...
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Laboratory Studies

No WBC count or serum chemistry abnormalities are expected in lymphomatoid papulosis (LyP) patients. However, they may be abnormal in patients with an associated lymphoma. Therefore, complete blood cell count and differential, blood chemistries, including lactate dehydrogenase (LDH), are recommended at baseline. Serology for human T-cell lymphotropic virus-1/2 is recommended only in areas with endemic human T-cell lymphotropic virus infection to identify adult T-cell lymphoma/leukemia, in which expression of CD30 by tumor cells can occur. [15]


Imaging Studies

No imaging studies are indicated for newly diagnosed patients with lymphomatoid papulosis (LyP), unless there are clinical concerns for a secondary lymphoma.



Obtain skin biopsy specimens from two or more fully developed inflammatory papules without necrosis or excoriation.

Skin biopsy is indicated to confirm the diagnosis and to exclude primary cutaneous ALCL, if possible. Because histologic distinction may be difficult, consult a dermatopathologist with experience in diagnosing lymphoproliferative skin disorders.


Histologic Findings

Upon low-power histologic examination, lymphomatoid papulosis shows a wedge-shaped dense dermal infiltrate of lymphoid cells with numerous eosinophils, neutrophils, and atypical lymphocytes. As much as 50% of the infiltrate shows the atypical lymphocytes. Epidermotropism of lymphoid cells may occur. Dermal vessels may show endothelial swelling, fibrin deposition, and red blood cell extravasation.

Histologically, lymphomatoid papulosis is divided into the following subtypes [29, 30] :

  • Type A is characterized by large (25-40 µm) CD30+ atypical cells intermingled with a prominent inflammatory infiltrate. The large tumor cells have polymorphic convoluted nuclei with a minimum of 1 prominent nucleolus and resemble Reed-Sternberg cells when binucleate, as is seen in HD. Type A lymphomatoid papulosis is the most common histologic variant and accounts for 75% of all lymphomatoid papulosis specimens.

  • Type B is characterized by smaller (8-15 µm) atypical cells with hyperchromatic cerebriform nuclei resembling the atypical lymphocytes in MF. CD30+ large cells are rare, but epidermotropism is more common in this variant. There is some concern that Type B lymphomatoid papulosis may be better classified as a papular variant of MF.

  • Type C (diffuse large cell type) is characterized by sheets of CD30+ anaplastic large cells indistinguishable from ALCL, with the exception of the minimal subcutaneous invasion. These lesions resolve spontaneously and are therefore classified as lymphomatoid papulosis; however, some authorities view this histologic variant as borderline ALCL or, perhaps, pcALCL. [31]

  • Type D epidermotropic CD8 variant of lymphomatoid papulosis mimics primary cutaneous aggressive epidermotropic CD8+ cytotoxic T-cell lymphoma histologically with CD8+ CD30+ atypical T cells infiltrating the epidermis. Clinically, patients present with rapidly ulcerating papulonodules. [32]

  • Type E angioinvasive lymphomatoid papulosis is characterized by an angiodestructive infiltrate of small-to-medium atypical lymphocytes with CD30+ and often CD8+ staining. [33]

Uncommonly, patients may have more than one histologic subtype of lymphomatoid papulosis. In 2013, 11 cases with spontaneously regressing papules were described harboring chromosomal rearrangements of the DUSP22-IRF4 locus on 6p25.3. [34] The overall findings suggest that these cases may represent a newly recognized of lymphomatoid papulosis subtype characterized by 6p25.3 rearrangements.

Immunophenotyping and molecular findings

CD 30 (Ki-1) expression is characteristic. The atypical lymphocyte is predominantly a CD4+ helper/inducer T cell with HLA-DR and interleukin 2 receptor (CD25) expression and variable loss of CD5 and/or CD7 antigen expression. CD30+ expression is characteristic, but, paradoxically, the small tumor cells in lymphomatoid papulosis type B are usually CD30 negative. Tumor cells in lymphomatoid papulosis may express cytotoxic molecules such as CD56, TIA-1, and granzyme B. CXCR3, a Th1 cell marker, is expressed in up to 85% of lymphomatoid papulosis cases. Emergence of CCR4 positivity, a Th2 marker common in pcALCL, has been hypothesized as a risk factor for malignant progression. CD8 lymphomatoid papulosis is now considered a distinct clinical entity.

Clonality in lymphomatoid papulosis is controversial, and not all cases of lymphomatoid papulosis in the literature are clonal as detected by analysis of T-cell antigen receptor genes. However, monoclonal rearrangement of the T-cell antigen receptor has been detected in 40-90% of lymphomatoid papulosis lesions, and identical clones have been demonstrated in the peripheral blood cells of patients with severe disease. One investigation suggested that the cell infiltrate in lymphomatoid papulosis comprises a mixture of polyclonal large atypical cells (CD30+) and smaller monoclonal T cells (CD30-negative). The (2;5)(p23;q35) translocation is not detected.



No staging scheme has been described for lymphomatoid papulosis.