Primary localized cutaneous lichen myxedematosus with light chain-restricted plasma cells: A distinct variant of the localized form of lichen myxedematosus

Lichen myxedematosus (LM) is a chronic cutaneous mucinosis that can present as a localized skin lesion or as a generalized systemic disease termed scleromyxedema. The differential diagnosis is determined by a combination of clinical presentation, serological studies, and histopathological examination. Currently, well-established and accepted histopathological features to distinguish localized LM from scleromyxedema have not been elucidated. Our recent publication, together with a retrospective literature review, suggests that the presence of groups of light chain-restricted plasma cells represents a distinct histopathological clue for the diagnosis of localized LM. In this report, we provide two additional cases of localized LM with lambda light chain-restricted plasma cells, together with clinical and histopathological findings that are similar to our previous publication. These cases support our theory that the light chain-restricted plasmacytic microenvironment is primarily attributed to the pathogenesis of localized LM. Therefore, we consider these cases to constitute a clinically and pathologically new variant of localized LM and name it primary localized cutaneous LM with light chain-restricted plasma cells.

DUSP22-IRF4 Rearranged CD30-Positive Primary Cutaneous Lymphoproliferative Disorder With Gamma/Delta Phenotype

ABSTRACT

CD30-positive primary cutaneous lymphoproliferative disorders (CD30 + PCLPD) are a heterogeneous group of cutaneous T-cell lymphoma (CTCL) that includes lymphomatoid papulosis (LyP) and primary cutaneous anaplastic large cell lymphoma. They exist as a clinical and pathological spectrum, which display significant overlap and variability. The diagnosis is made based on correlation between clinical and histopathologic findings. LyP with 6p25.3 rearrangement subtype represents <5% of LyP cases and is defined by DUSP22-IRF4 rearrangement on 6p25.3 locus. The reported cases express the alpha/beta T-cell receptor and follow an indolent clinical behavior typical of LyP. The same rearrangement is detected in 28% of anaplastic large cell lymphoma. We hereby present an extraordinary case of CD30 + PCLPD with DUSP22-IRF4 rearrangement and novel expression of gamma/delta T-cell immunophenotype in a young patient. Although the gamma/delta T-cell immunophenotype has been described in many other T-cell lymphomas, this is the first reported association with CD30 + PCLPD with DUSP22-IRF4 rearrangement.

Spindle Cell Lipoma With Florid Primary Follicular Lymphocytic Hyperplasia: A Novel Association With Potential Diagnostic Pitfalls

ABSTRACT

Spindle cell lipoma (SCL) is a benign subcutaneous lipomatous neoplasm with a heterogeneous histologic appearance that varies greatly depending on the amount of fat, collagen, and myxoid stroma, which define the multiple subtypes of SCL, such as fat poor SCL, pseudoangiomatous SCL, and dendritic fibromyxolipoma. Cutaneous lymphoid hyperplasia is a spectrum of benign conditions characterized by reactive B-cell and T-cell cutaneous lymphocytic infiltrates. Cutaneous B-cell lymphoid hyperplasia is a heterogeneous group of non-neoplastic conditions that can be observed as reactive phenomena to infections, medications, allergens, or neoplasms and must be distinguished from cutaneous B-cell lymphomas. Here, we report a novel case of spindle cell lipoma, associated with B-cell primary lymphoid follicular hyperplasia, mixed within the tumor in a peculiar pattern, while discussing potential diagnostic pitfalls with low-grade B-cell lymphomas. This is the first report of such association in the literature.

Lichen Planopilaris Pemphigoides: A Novel Bullous Dermatosis Due to Programmed Cell Death Protein-1 Inhibitor Therapy

ABSTRACT

Lichen planus pemphigoides (LPPemph), apart from bullous pemphigoid, is a rare bullous dermatosis that can be induced by programmed cell death protein-1 (PD-1)/PD ligand 1 (PD-L1) inhibitors. The primary location of PD-1/PD-L1 inhibitor-induced LPPemph has previously only been reported at the nonfollicular dermal-epidermal junction. We present a case of nivolumab-induced LPPemph with an intense perifollicular lichenoid reaction, prominent multifocal perifollicular clefting, which in addition, was also accompanied by linear IgG and C3 immunofluorescence deposits along the dermal-epidermal junction as well as demonstrating a perifollicular pattern. Intriguingly, the serological study of BP180 and BP230 antibodies was negative, suggesting the presence of additional novel antibodies, which primarily favor hair follicles and may contribute to the pathogenesis. Therefore, we consider this entity a novel variant of PD-1/PD-L1 inhibitor-induced bullous dermatosis. To the best of our knowledge, this is the first report that highlights perifollicular bullae accompanied by immunofluorescence findings in a PD-1/PD-L1 inhibitor-induced lesion. We propose a new immunotherapy associated entity, lichen planopilaris pemphigoides, and emphasize the significance of perifollicular changes in the pathogenesis.

Overlapping Features of Primary Cutaneous Marginal Zone Lymphoproliferative Disorder and Primary Cutaneous CD4 + Small/Medium T-Cell Lymphoproliferative Disorder : A Diagnostic Challenge Examined by Genomic Analysis

Primary cutaneous marginal zone lymphoproliferative disorder (PCMZL) and primary cutaneous CD4 + small/medium T-cell lymphoproliferative disorder (CD4 + TLPD) are indolent lymphoproliferative disorders. However, cases with overlapping features can be challenging. We identified 56 CD4 + TLPD and 38 PCMZL cases from our pathology archives. Clinical, morphologic, and immunophenotypic features were reviewed. Polymerase chain reaction for immunoglobulin (IG) and T-cell receptor gamma (TRG) gene rearrangements were analyzed. Next-generation sequencing studies were performed on 26 cases with adequate material, 19 with CD4 + TLPD, and 7 with PCMZL. CD4 + TLPD presented mostly (91%) as solitary lesions, located in the head and neck area (64%), while PCMZL occurred mostly in the upper extremity (47%) and trunk (34%). Lesions were sometimes multiple (40%) and recurrences (67%) were more common. Cases of PCMZL had an increase in reactive CD3 + T cells, with frequent programmed cell death protein 1 expression, whereas cases of CD4 + TLPD often contained abundant reactive B cells. Twenty-five cases were identified as having overlapping features: 6 cases of PCMZL were clonal for both IG and TRG; 11 cases of CD4 + TLPD were clonal for IG and TRG and 6 cases of CD4 + TLPD had light chain-restricted plasma cells. By next-generation sequencing, 23 variants were detected in 15 genes, with PCMZL more likely to show alterations, most commonly affecting TNFAIP3 and FAS, altered in 5 cases. Both entities have an indolent clinical course with response to conservative therapy and management, and warrant interpretation as a lymphoproliferative disorder rather than overt lymphoma.

A case of leprosy in central Florida

Hansen disease, also known as leprosy, is a chronic granulomatous infectious disease that is caused by Mycobacterium leprae. We report an unusual case of a 65-year-old man who presented with multiple anesthetic, annular, erythematous, scaly plaques with a raised border without any known exposures to leprosy. Histologic examination revealed a perineural lymphohistiocytic infiltrate and rare bacilli demonstrated on Fite staining. After confirmation with polymerase chain reaction (PCR) and consultation with the National Hansen's Disease Program (Baton Rouge, Louisiana), the patient was placed on a regimen of rifampicin 600 mg once monthly and dapsone 100 mg once daily for 6 months, which showed considerable improvement. This case demonstrates the identification of leprosy in central Florida, a region that is not known to be endemic to the disease. Leprosy, however rare, must be part of a practitioner's differential diagnosis even without history of traditional exposures.

Abstract 1208: Discovery of a previously undescribed cutaneous T-cell neoplasm with chromosomal rearrangements of 6p25.3

Background: Cutaneous T-cell neoplasms display markedly heterogeneous clinical behavior despite often similar pathologic features. For example, transformed mycosis fungoides (tMF) has a poor prognosis and requires intensive therapy whereas lymphomatoid papulosis (LyP) is an indolent lymphoproliferative disorder with spontaneously resolving lesions. These entities have overlapping histologic features and no molecular tools currently exist to aid in subclassification.

Methods: We identified 11 T-cell neoplasms with histologic appearances distinct from previously described cutaneous T-cell neoplasms but with features overlapping those of both tMF and LyP. The phenotypic and genetic characteristics of the tumors were studied using immunohistochemistry and fluorescence in situ hybridization, respectively. Clinical data on presentation, treatment, evolution of the lesions, and follow-up were obtained.

Results: All patients were older adults (mean age, 75 yr; range, 67-88 yr; 9M:2F). Clinical presentations were similar, with papulonodular skin lesions (0.3-1.0 cm) restricted to a single body area in all but two patients. Histologically there was an extensive atypical lymphoid infiltrate in the epidermis and a dermal tumor containing large transformed cells with numerous mitotic figures and apoptotic bodies. All tumors had a T-cell phenotype and expressed CD30 in both dermal and epidermal components. No case expressed ALK. Most cases had a high proliferative rate (&gt;80%) by Ki67 staining. FISH analysis demonstrated rearrangements of the DUSP22-IRF4 locus on 6p25.3 in all cases. No patient had evidence of systemic disease on imaging studies. In 4 untreated patients, papules began to regress spontaneously a few weeks after presentation, with complete resolution within a month or two. Seven patients were treated with local excision (with or without cryotherapy) or radiotherapy. All non-excised lesions ultimately regressed. All patients were alive at last follow-up (median, 21 mo; range, 7-150 mo). Cutaneous recurrences occurred in 5 patients. At last follow-up only 1 patient had active lesions, which were confined to the presenting site. The remaining 10 patients had been disease-free from 2 to 32 months.

Conclusions: Despite pathologic features mimicking an aggressive lymphoma, the benign clinical course observed in all 11 patients suggests these cases represent a newly recognized subtype of LyP. These neoplasms are characterized by 6p25.3 rearrangements, representing the first recurrent genetic abnormality identified in LyP. In contrast, we previously have shown absence of these rearrangements in tMF. Distinction of LyP from tMF is critical in this older patient population unlikely to tolerate intensive therapy. Thus, detection of 6p25.3 rearrangements represents a new tool for molecular classification of cutaneous T-cell neoplasms.

Citation Format: Andrew L. Feldman, Laszlo J. Karai, Marshall E. Kadin, Eric D. Hsi, Jason C. Sluzevich, Rhett P. Ketterling, Ryan A. Knudson. Discovery of a previously undescribed cutaneous T-cell neoplasm with chromosomal rearrangements of 6p25.3. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1208. doi:10.1158/1538-7445.AM2013-1208

Reactivation of DNA viruses in association with histone deacetylase inhibitor therapy: a case series report

Histone deacetylase inhibitors are a class of anti-neoplastic agents that induce growth arrest, differentiation, and/or apoptotic cell death of transformed cells in vitro and in vivo. A phase II study exploring the efficacy of romidepsin, an histone deacetylase inhibitor, in patients with cutaneous or peripheral T-cell lymphomas was initiated at the National Cancer Institute. To date, over 120 patients with T-cell lymphoma have been treated on a multi-institutional phase II trial of romidepsin. Reactivation of latent DNA viruses including EBV, HBV, and VZV is well described as a consequence of the immune suppression associated with systemic chemotherapy. The incidence of viral reactivation in patients treated with histone deacetylase inhibitors is not yet known. We report the observation of EBV-associated illnesses in 2 patients and the reactivation of HBV in an additional patient treated with romidepsin. These cases may represent reactivation of DNA viruses due to histone deacetylase inhibitor induced immunosuppression, or direct promotion of viral replication via histone deacetylase inhibitor induced chromatin remodeling, or, alternatively, may be related to the underlying disease process. These observations suggest that vigilance for DNA virus reactivation is needed to quantify the risk in patients treated with histone deacetylase inhibitors.

Elephantiasis nostras verrucosa in a patient with systemic sclerosis

Elephantiasis nostras verrucosa (ENV) is an unusual skin condition characterized by dermal fibrosis and hyperkeratotic verrucous lesions resulting from chronic nonfilarial lymphoedema. The condition is similar to 'elephantiasis tropica', in which elephantiasis develops secondary to filariasis. Lymphatic obstruction can be primary or due to various causes such as surgery, tumour, radiation, congestive heart failure or obesity. Recurrent attacks of cellulitis lead to further impairment of lymphatic drainage, causing permanent swelling, dermal fibrosis and epidermal thickening. We report a case of a 56-year-old man with systemic sclerosis (SS), who presented with painful lesions on both legs, consistent with ENV. He developed extensive, fungating, papillomatous lesions on the skin of the legs, toes and dorsa of the feet over a period of 3 years. Histology revealed dense dermal fibrosis, oedema of the papillary dermis and extensive pseudo-epitheliomatous changes. To our knowledge, this is the first report of ENV in which SS was considered to be the primary cause for the impairment of lymphatic flow.

Perineural resiniferatoxin selectively inhibits inflammatory hyperalgesia

Resiniferatoxin (RTX) is an ultrapotent capsaicin analog that binds to the transient receptor potential channel, vanilloid subfamily member 1 (TRPV1). There is a large body of evidence supporting a role for TRPV1 in noxious-mediated and inflammatory hyperalgesic responses. In this study, we evaluated low, graded, doses of perineural RTX as a method for regional pain control. We hypothesized that this approach can provide long-term, but reversible, blockade of a portion of nociceptive afferent fibers within peripheral nerves when given at a site remote from the neuronal perikarya in the dorsal root ganglia. Following perineural RTX application to the sciatic nerve, we demonstrated a significant inhibition of inflammatory nociception that was dose- and time-dependent. At the same time, treated animals maintained normal proprioceptive sensations and motor control, and other nociceptive responses were largely unaffected. Using a range of mechanical and thermal algesic tests, we found that the most sensitive measure following perineural RTX administration was inhibition of inflammatory hyperalgesia. Recovery studies showed that physiologic sensory function could return as early as two weeks post-RTX treatment, however, immunohistochemical examination of the DRG revealed a partial, but significant reduction in the number of the TRPV1-positive neurons. We propose that this method could represent a beneficial treatment for a range of chronic pain problems, including neuropathic and inflammatory pain not responding to other therapies.