Angioinvasive Lymphomatoid Papulosis: Another Case of a Newly Described Variant

Histologic and Immunohistochemical Patterns in Lymphomatoid Papulosis: A Systematic Review of Published Cases

Based on histologic and genetic patterns, the current World Health Organization (WHO) classification distinguishes six subtypes of lymphomatoid papulosis (Lyp). The aim of our article was to analyze the frequency of histologic and immunohistochemical features of different Lyp subtypes reported in the literature. We used PubMed advanced search builder to systematically review and evaluate English and German literature of Lyp from 1968 to April 2022. We considered only papers in which histopathologic features were mentioned in detail. We identified 48 publications with a total of 518 cases. The diagnoses were based on the diagnostic criteria at the time of publication. In Lyp A and Lyp B a CD8+ phenotype was more often reported than expected (53% and 52%, respectively). A double positive phenotype (CD4+/CD8+) was found in 28% of Lyp E and a double negative (CD4-/CD8-) in 50% of Lyp with 6p25.3 rearrangement. High rates of folliculo- and syringotropism were reported in both Lyp A and B. Surprisingly, strong epidermotropism occurred in 20/38 (53%) cases reported as Lyp B and in 43/64 (67%) of Lyp D cases. The predominating phenotype in Lyp D was CD8+, while TIA-1/granzymeB/perforin expression was reported in 37/46 (80%), and CD56 was expressed in 13/47 (28%) of the investigated cases. The limitation of the data is due to the retrospective approach with diagnostic criteria changing over time and on a case selection in some publications. However, the data indicate that the Lyp subtypes overlap more than assumed. They also show that a prospective study is needed to obtain valid data on the frequency distribution of certain histopathologic criteria.

Lymphomatoid papulosis types D and E: a multicentre series of the French Cutaneous Lymphomas Study Group

BACKGROUND

Lymphomatoid papulosis (LyP) type D (LyP D) and type E (LyP E) have recently been described in small series of cases or isolated case reports.

AIM

To further describe the clinical and histological features of LyP D and E based on a retrospective multicentre study.

METHODS

The clinical and histopathological features of 29 patients with an initial diagnosis of LyP D or LyP E were retrospectively assessed using standardized forms.

RESULTS

After exclusion of 5 cases, 24 patients (14 LyP D, 10 LyP E) were enrolled in the study. The median follow-up was 2.5 years (range 1 month to 13 years). LyP D was characterized by multiple recurrent self-regressing small papules that developed central erosion or necrosis, whereas LyP E presented as papulonodular lesions that rapidly evolved into necrotic eschar-like lesions > 10 mm in size. Epidermal changes were more frequent in LyP D, whereas dermal infiltrates were deeper in LyP E. Anaplastic cytology was rare and the DUSP22 rearrangement was never observed. Two patients (8%) had an associated cutaneous lymphoma.

CONCLUSION

LyP D and E have distinct clinical findings and may be associated with other cutaneous lymphomas.

Practical Management of CD30⁺ Lymphoproliferative Disorders

Primary cutaneous CD30⁺ lymphoproliferative disorders (LPDs) account for approximately 25% of cutaneous lymphomas. Although these LPDs are clinically heterogeneous, they can be indistinguishable histologically. Lymphomatoid papulosis rarely requires systemic treatment; however, multifocal primary cutaneous anaplastic large cell cutaneous lymphoma and large cell transformation of mycosis fungoides are typically treated systemically. As CD30⁺ LPDs are rare, there is little published evidence to support a specific treatment algorithm. Most studies are case reports, small case series, or retrospective reviews. This article discusses various treatment choices for each of the CD30⁺ disorders and offers practical pearls to aid in choosing an appropriate regimen.

Cutaneous CD30-Positive Lymphoproliferative Disorders

Cutaneous CD30+ lymphoproliferative disorders are the second most common types of cutaneous T-cell lymphomas. They represent a well-defined spectrum encompassing lymphomatoid papulosis (LyP), primary cutaneous anaplastic large-cell lymphoma (pcALCL), and borderline lesions. They share the expression of CD30 as a common phenotypic hallmark, but they differ in their clinical presentation, course, and histologic features. New variants have been recently identified, including CD8+ epidermotropic LyP type D, angioinvasive LyP type E, and ALK-positive pcALCL. This review describes clinical, histopathologic, and phenotypic variants; their differential diagnoses (benign and malignant); and the role of CD30 as a diagnostic, prognostic, and therapeutic marker.