Mycosis Fungoides and Granulomatous Slack Skin: A Single Entity With Distinct Clinical Phenotypes

ABSTRACT

Granulomatous cutaneous T-cell lymphoma includes mycosis fungoides with significant granulomatous inflammation (GMF) and granulomatous slack skin (GSS), listed in the WHO classification as a subtype of mycosis fungoides (MFs). 1 These overlapping entities have shared clinical and histopathologic features which can present a diagnostic challenge. The dominance of the granulomatous infiltrate and the often sparse lymphocytic infiltrate frequently with minimal cytological atypia are features that distract from the correct diagnosis, even when raised by the clinician. We describe the clinical and histopathologic characteristics of 3 cases of granulomatous cutaneous T-cell lymphoma, illustrate the close clinical and pathologic relationship between GMF and GSS and emphasize the diagnostic difficulties that the granulomatous infiltrate can present. Furthermore, we demonstrate, for the first time, considerable elastolysis in a significant proportion of classical (Alibert-Bazin) MF lesions and therefore postulate that the differences observed between GMF and GSS are one of degree and secondary to their anatomic location rather than reflecting meaningful separate entities.

Prominent Blasts in Primary Cutaneous CD4+ Small/Medium T-Cell Lymphoproliferative Disorder. A Reconsideration of Diagnostic Criteria

ABSTRACT

Primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder (PCSM-LPD), recently downgraded from a T-cell lymphoma, is a poorly characterized histopathological entity. Presenting as a solitary lesion that often grows rapidly, it may raise suspicion for a cutaneous B-cell lymphoma. However, classically, the dermal lymphoid proliferation is predominantly CD4+ with a follicular T-helper profile and a smaller B-cell fraction. Diagnostic uncertainty may arise when B cells are present in large numbers, a B-cell clone is present, or large cell populations are seen. To meet the diagnostic criterion of PCSM-LPD, large cells should not constitute more than 30% of the infiltrate. The 2 cases presented in this article caused diagnostic uncertainty owing to the observation of high numbers of large cells and in one case the presence of a B-cell clone, on the background of otherwise typical clinicopathological features of PCSM-LPD. We review the literature specifically regarding the prevalence of large cell populations and their immunophenotypic characteristics and in light of this discuss whether a current diagnostic criterion should be reconsidered.

Primary Cutaneous CD4+ Small/Medium T-Cell Lymphoproliferative Disorder or Primary Cutaneous Marginal Zone B-Cell Lymphoma? Two Distinct Entities With Overlapping Histopathological Features

ABSTRACT

Primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder and primary cutaneous marginal zone B-cell lymphoma are 2 distinct entities with several overlapping features which can result in diagnostic uncertainty. Clinically, they both follow an indolent course and present with solitary or multiple papules or nodules. Histologically, they are characterized by polymorphous dermal infiltrates rich in mixed populations of B cells and T cells, often in similar proportions. The histological hallmark of primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder is the presence of follicular T-helper cells within the infiltrate and has historically been used as a marker for differentiating between the 2 conditions. However, there is now mounting evidence that follicular T-helper cells are also seen in primary cutaneous marginal zone B-cell lymphoma and nodal marginal zone lymphoma. The 2 cases presented herein caused diagnostic uncertainty because they displayed appreciable features of both conditions. We discuss the potential mechanisms behind these overlapping histopathological features and hypothesize a model that explores the idea of a collective organoid response to an antigenic stimulus.

Follicular T-Helper Cells in Marginal Zone Lymphoma: Evidence of an Organoid Immune Response

INTRODUCTION

Primary cutaneous marginal zone B-cell lymphoma (MZL) follows an indolent clinical course. Histopathologically, there is a polymorphous infiltrate that includes small lymphocyte-like and centrocyte-like B cells and plasma cells usually with a substantial T-cell fraction. Primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder, in which the signature cells have a follicular T-helper (TFH) phenotype and are admixed with numerous B cells. Thus, both present histologies of combined B-cell and T-cell infiltrates and represent differential diagnoses. The presence of TFH in MZL has yet to be elucidated.

METHODS

Forty-one biopsies from 40 cases of MZL and 7 cases of lymphoid hyperplasia cutis (LCH) were stained with antibodies to follicular T-helper cells, including Bcl-6, PD-1, ICOS, and CD10, as part of their diagnostic workup, were reviewed, and the stained slides were evaluated semiquantitively. Five reactive lymph nodes were also evaluated as controls.

RESULTS

All cases of MZL and LCH contained TFH, albeit usually in low proportions. There were repeated differences in levels of expression between TFH markers, with PD1 and Bcl-6 being the most prevalent. The pattern of involvement in MZL and LCH closely mirrored that observed in the reactive lymph nodes.

CONCLUSION

MZL includes TFH cells, similar to reactive lymph nodes, and a complexity of cell types. This provides evidence of an organoid immune response challenging its simple categorization as a malignancy.

Management of skin cancer in recipients of solid organ transplants

Recent improvements in post-transplant care have led to an increased life expectancy for recipients of organ transplants. These patients require lifelong immunosuppression, which is associated with an increased incidence of malignant disease. Skin cancers are the most common malignancies seen in recipients of organ transplants and are associated with significant morbidity and mortality. This review describes factors pertaining to the development and prognosis of skin cancers in recipients of organ transplants, as well as outlining prevention and management strategies in this cohort.

U.K. consensus statement on safe clinical prescribing of bexarotene for patients with cutaneous T-cell lymphoma

BACKGROUND

Bexarotene is a synthetic retinoid from the subclass of retinoids called rexinoids which selectively activate retinoid X receptors. It has activity in cutaneous T-cell lymphoma (CTCL) and has been approved by the European Medicines Agency since 1999 for treatment of the skin manifestations of advanced-stage (IIB-IVB) CTCL in adult patients refractory to at least one systemic treatment. In vivo bexarotene produces primary hypothyroidism which may be managed with thyroxine replacement. It also affects lipid metabolism, typically resulting in raised triglycerides, which requires prophylactic lipid-modification therapy. Effects on neutrophils, glucose and liver function may also occur. These side-effects are dose dependent and may be controlled with corrective therapy or dose adjustments.

OBJECTIVES

  To produce a U.K. statement outlining a bexarotene dosing schedule and monitoring protocol to enable bexarotene prescribers to deliver bexarotene safely for optimal effect.

METHODS

 Leaders from U.K. supraregional centres produced this consensus statement after a series of meetings and a review of the literature.

RESULTS

 The statement outlines a bexarotene dosing schedule and monitoring protocol. This gives instructions on monitoring and treating thyroid, lipid, liver, blood count, creatine kinase, glucose and amylase abnormalities. The statement also includes algorithms for a bexarotene protocol and lipid management, which may be used in the clinical setting.

CONCLUSION

 Clinical prescribing of bexarotene for patients with CTCL requires careful monitoring to allow safe administration of bexarotene at the optimal dose.

Treatment of severe, recalcitrant, chronic plaque psoriasis with fumaric acid esters: a prospective study

BACKGROUND

Fumaric acid esters (FAE) are used in Germany as a first-line systemic treatment for chronic plaque psoriasis, with proven efficacy and low toxicity. Their use in the U.K. is variable, and they remain unlicensed. Consequently, efficacy and safety data from U.K. patients is limited and their place in the psoriasis treatment armamentarium is unclear.

OBJECTIVES

To examine the efficacy and safety of FAE in a prospective cohort of U.K. patients with severe, treatment-recalcitrant, chronic plaque psoriasis.

METHODS

A single-centre, open, nonrandomized, prospective study was performed in a regional referral centre for patients with severe psoriasis. Outcomes were measured by the Psoriasis Area and Severity Index (PASI), Dermatology Life Quality Index (DLQI), blood investigations and adverse events monitoring.

RESULTS

Eighty patients were recruited. Fifty-nine per cent were taking a concomitant oral antipsoriatic agent; 20% achieved a PASI-50, 8% a PASI-75 and 4% a PASI-90 on intention-to-treat analysis at 3 months with an overall, statistically significant, reduction in PASI from 13.9 + or - 9.0 to 11.3 + or - 9.2 (P < 0.0001). At 3 months, lymphopenia was seen in 33% of the cohort with significantly lower counts in patients responsive to FAE (P = 0.008). In addition, by 3 months, 36% of concomitant antipsoriatic medication had been stopped and 25% of doses had been reduced without loss of disease control. Side-effects (most commonly diarrhoea, abdominal pain and flushing) were reported by 74% of patients resulting in cessation of FAE in 36%.

CONCLUSIONS

FAE is a useful alternative treatment option in patients with severe, treatment-resistant, chronic plaque psoriasis and can allow dose reduction, and subsequent cessation, of other, potentially more toxic agents.

Treatment of severe, recalcitrant, chronic plaque psoriasis with fumaric acid esters: a prospective study

BACKGROUND

Fumaric acid esters (FAE) are used in Germany as a first-line systemic treatment for chronic plaque psoriasis, with proven efficacy and low toxicity. Their use in the U.K. is variable, and they remain unlicensed. Consequently, efficacy and safety data from U.K. patients is limited and their place in the psoriasis treatment armamentarium is unclear.

OBJECTIVES

To examine the efficacy and safety of FAE in a prospective cohort of U.K. patients with severe, treatment-recalcitrant, chronic plaque psoriasis.

METHODS

A single-centre, open, nonrandomized, prospective study was performed in a regional referral centre for patients with severe psoriasis. Outcomes were measured by the Psoriasis Area and Severity Index (PASI), Dermatology Life Quality Index (DLQI), blood investigations and adverse events monitoring.

RESULTS

Eighty patients were recruited. Fifty-nine per cent were taking a concomitant oral antipsoriatic agent; 20% achieved a PASI-50, 8% a PASI-75 and 4% a PASI-90 on intention-to-treat analysis at 3 months with an overall, statistically significant, reduction in PASI from 13.9 + or - 9.0 to 11.3 + or - 9.2 (P < 0.0001). At 3 months, lymphopenia was seen in 33% of the cohort with significantly lower counts in patients responsive to FAE (P = 0.008). In addition, by 3 months, 36% of concomitant antipsoriatic medication had been stopped and 25% of doses had been reduced without loss of disease control. Side-effects (most commonly diarrhoea, abdominal pain and flushing) were reported by 74% of patients resulting in cessation of FAE in 36%.

CONCLUSIONS

FAE is a useful alternative treatment option in patients with severe, treatment-resistant, chronic plaque psoriasis and can allow dose reduction, and subsequent cessation, of other, potentially more toxic agents.

Congenital anetoderma in a preterm infant

Isolated, small lesions of anetoderma presenting at birth have been reported in twins born at 25 weeks of gestational age. We report the first case of widespread congenital anetoderma occurring in an infant born at 24 weeks of gestation weighing 640 g and discuss the potential factors in its etiology.

Three cases of lymphomatoid papulosis with a CD56+ immunophenotype

We report 3 cases of lymphomatoid papulosis (LyP) with a CD56+, cytotoxic immunophenotype. All 3 patients presented with clinical histories typical of LyP, with one patient having associated mycosis fungoides. Histologically, two cases were type A LyP and one was type B. All 3 cases demonstrated a T-cell receptor clone in lesional skin without evidence of blood involvement. The atypical lymphocytes in each of the 3 cases expressed cytotoxic granules (T-cell intracellular antigen-1+ and granzyme B+) and were CD8+ and CD56+. Expression of CD56 is associated with a poor prognosis in subcutaneous panniculitis-like T-cell lymphoma and blastic natural killer cell lymphoma. However, the two cases of CD56+ LyP previously reported and the 3 cases in this series all appear to be pursuing an indolent course with no evidence of systemic disease.

Mycosis fungoides with a CD56+ immunophenotype

We report 3 cases of mycosis fungoides (MF) with a CD56+ cytotoxic immunophenotype. Each patient presented with a different clinical phenotype: one exhibited limited poikilodermatous patches (skin stage T1); one, widespread hypopigmented lesions (skin stage T2); and one, poikiloderma with a single cutaneous tumor (skin stage T3). MF was confirmed both histologically and by the presence of a T-cell receptor clone in lesional skin in all cases. CD56 and T-cell intracellular antigen-1 were expressed by the malignant lymphocytes in all patients and two expressed CD8. No sample demonstrated loss of the pan T-cell markers CD2 or CD3. None of the 3 developed systemic disease and T-cell receptor gene analysis of peripheral blood was polyclonal in all cases. Only 3 cases of CD56+ MF have been reported previously, none of which exhibited tumor-stage disease. Currently, the disease in our patients appears to be behaving in a manner similar to that predicted for MF with a normal immunophenotype but the prognosis has to be guarded in view of the rarity of this subtype.

Necrobiotic xanthogranuloma with paraproteinaemia

Necrobiotic xanthogranuloma is a rare cutaneous condition that can be mistaken for atypical necrobiosis lipoidica. It has a strong association with a paraproteinaemia, which may progress to frank haematological malignancy. We describe four patients with variable cutaneous features, and their treatment response.

Fine mapping of chromosome 10q deletions in mycosis fungoides and sezary syndrome: Identification of two discrete regions of deletion at 10q23.33-24.1 and 10q24.33-25.1

Previous cytogenetic studies in mycosis fungoides (MF) and Sezary syndrome (SS) have identified a large and poorly defined area of chromosomal deletion on chromosome 10q. We report an extensive fine-mapping allelotyping study using 19 microsatellite markers in the region 10q22.3-10q26.13. Allelic loss was identified by loss of heterozygosity analysis in 26 of 60 (43%) cases: 15 of 45 (33%) with MF and 11 of 15 (73%) with SS. MF and SS samples showed similar patterns of allelic loss with the identification of two discrete regions of deletion which were mutually exclusive in all but two cases. Within the first region of deletion at 10q23.33-10q24.1, around microsatellite marker D10S185 (2.77 Mb), 23 genes were identified, including three (KIF11, HHEX, and HELLS) with functions that, if dysregulated, could be critical in MF and SS. The second region of deletion, 10q24.33-10q25.1, around microsatellite marker D10S530 (3.92 Mb), encodes 11 genes, the majority of which have poorly identified functions. This extensive allelotyping study provides the basis for future highly selective candidate gene analyses.

Outcome in 34 patients with juvenile-onset mycosis fungoides

BACKGROUND

Mycosis fungoides (MF) is predominantly a disease of older patients, but occasionally occurs in children. The aims of the current study were to describe the clinical presentation, pathologic features, and disease progression (DP) in patients who developed MF before age 16 years.

METHODS

A retrospective study was performed. Patients with juvenile-onset MF were identified from our databases. Clinical features were determined from the medical records and patient interviews. Histologic, immunohistochemical, and T-cell receptor (TCR) gene analysis was performed.

RESULTS

Thirty-four patients were identified: 50% had Stage IA disease, 47% had Stage IB disease, and 3% had Stage IIA disease. The male-to-female ratio was 2:1. Clinical features included hypopigmented lesions (24%), poikiloderma (26%), pilotropic disease (9%), and disease associated with lymphomatoid papulosis (18%). Twenty-eight patients had diagnostic histology, and six patients were included on the basis of compatible histology and a TCR clone in lesional skin. A cytotoxic immunophenotype was observed in 38%, including 71% of patients with hypopigmented lesions. Overall disease-specific survival (DSS) rates at 5 and 10 years were 95% and 93%, respectively. DP rates were 5% at 5 years and 29% at 10 years. Subgroup analysis demonstrated improved DSS and reduced DP in patients with Stage IA disease, those with hypopigmented or poikilodermatous lesions, and those with associated lymphomatoid papulosis.

CONCLUSIONS

The prognosis for juvenile-onset MF is similar to that of adult-onset disease. There was an overrepresentation of a cytotoxic phenotype, which was most marked in hypopigmented variants. Widespread cutaneous disease (Stage IB) indicated a less favorable outcome.

Mycosis fungoides involving the oral mucosa in a child

Involvement of the oral mucosa in cutaneous T-cell lymphoma is uncommon and is usually associated with a poor prognosis (the majority of patients dying from the disease within 3 years of the diagnosis of oral involvement). We report the first case of intraoral mycosis fungoides occurring in a child. In addition, our patient has had intraoral disease for 3 years and is currently systemically well with no evidence of cutaneous or systemic disease progression.