Frequency of Hypopigmented Mycosis Fungoides in Egyptian Patients Presenting With Hypopigmented Lesions of the Trunk

Mycosis fungoides refractory to treatment - importance of a multidisciplinary approach

We report a case of difficult-to-control mycosis fungoides (MF), where the role of the dental surgeon was crucial for the control and prognosis of the disease. A 62-year-old female patient diagnosed with MF had a previous record of red patches and small raised bumps on the face, along with a cancerous growth in the cervical and vulvar region. The patient was initially treated with methotrexate and local radiotherapy without resolution. Chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone was then started (CHOP protocol). The dental team of a reference hospital was consulted to evaluate swelling in the anterior region of the palate, which had been developing for two months, reporting discomfort when eating. The role of the dentistry team was fundamental in the differential diagnosis of oral lesions with dental infections, second neoplasia, or even a new site of disease manifestation, in addition to controlling mucosal changes resulting from chemotherapy. After ruling out dental infection, the dentistry team performed a lesion biopsy to confirm the diagnosis. The histopathological and immunohistochemical analysis showed atypical lymphoid infiltration of T cells (CD3+/CD4+/CD7-/CD8-), coexpression of CD25, and presence of CD30 cells, corresponding to the finding for MF. Identifying CD30 + allowed for a new chemotherapy protocol with brentuximab vedotin (BV) combined with gemcitabine. This protocol effectively controlled MF, which previous protocols had failed to do. The diagnosis by the dental team was essential for therapeutic change and improvement of the patient's clinical condition without the need for invasive medical procedures.

Fifth Edition of the World Health Organization Classification of Tumors of the Hematopoietic and Lymphoid Tissues: Mature T-Cell, NK-Cell, and Stroma-Derived Neoplasms of Lymphoid Tissues

This review focuses on mature T cells, natural killer (NK) cells, and stroma-derived neoplasms in the fifth edition of the World Health Organization classification of hematolymphoid tumors, including changes from the revised fourth edition. Overall, information has expanded, primarily due to advancements in genomic understanding. The updated classification adopts a hierarchical format. The updated classification relies on a multidisciplinary approach, incorporating insights from a diverse group of pathologists, clinicians, and geneticists. Indolent NK-cell lymphoproliferative disorder of the gastrointestinal tract, Epstein-Barr virus-positive nodal T- and NK-cell lymphoma, and several stroma-derived neoplasms of lymphoid tissues have been newly introduced or included. The review also provides guidance on how the fifth edition of the World Health Organization classification of hematolymphoid tumors can be applied in routine clinical practice.

Hypopigmented lesions in pityriasis lichenoides chronica patients: Are they only post-inflammatory hypopigmentation?

BACKGROUND/OBJECTIVES

Pityriasis lichenoides chronica (PLC) lesions are reported to subside with post-inflammatory hypopigmentation (PIH); hence, the most widely perceived nature of hypopigmented macules in PLC is PIH. However, to the best of our knowledge, no studies describing histopathological findings in these lesions are reported in literature. The aim of this study is to evaluate the hypopigmented lesions encountered in PLC patients and to shed light on their histopathological features.

METHODS

A cross-sectional observational study included twenty-one patients with PLC recruited in a period of twelve months. Clinical characteristics of each patient were collected. A skin biopsy from hypopigmented lesions whenever present was taken and assessed with routine haematoxylin and eosin stain.

RESULTS

Seventeen patients (81%) were less than 13 years old. Most patients (85.7%) demonstrated diffuse distribution of lesions. Hypopigmented lesions were present on the face in 12 (57.14%) patients. Histopathologically, hypopigmented lesions showed features of post-inflammatory hypopigmentation in 19% of patients, residual PLC in 52.4% and active PLC 28.6% of patients.

CONCLUSION

Hypopigmented lesions in PLC were noted mainly in younger ages, histopathologically they may show features of active or residual disease, beyond post-inflammatory hypopigmentation. Consequently active treatment for patients presenting predominantly with hypopigmented lesions could be required to control the disease.

Hypopigmented Mycosis Fungoides: A Clinical and Histopathology Analysis in 9 Children

BACKGROUND

Hypopigmented mycosis fungoides (HMF) is an uncommon variant of mycosis fungoides.

AIMS

To study the clinical and histopathology presentation in children with HMF.

METHOD

We reviewed 9 children diagnosed with HMF. The clinical data were collected and analyzed.

RESULT

Eight boys and 1 girl were included, with a median onset age of 7.4 year old and median age of diagnosis of 10.5 year old. Multiple hypopigmented patches were observed in all patients, and 5 patients exhibited multiple scaly erythema at the center of hypopigmented patches. Histopathology showed atypical lymphocytes with hyperchromatic, irregular, and cerebriform nuclei, infiltrated in the epidermis and dermis. Pautrier's microabscesses was noted in 6 of 9 patients, and papillary dermal fibroplasia was noted in 6 of 9 patients. CD8 predominance was detected in 4 of 6 patients. Four patients were simultaneously subjected to skin biopsy on hypopigmented patches and scaly erythema simultaneously. Compared with hypopigmented specimens, erythema biopsy detected deeper and denser infiltration of atypical lymphoid cells in 3 of 4 patients, higher CD4+/CD8+ ratio in 4 of 4 patients, more CD5 loss in 2 of 4 patients, and more CD7 loss in 2 of 4 patients. TCR gene monoclonal rearrangement was detected in 2 of 5 patients. Narrowband ultraviolet B phototherapy was applied in 7 patients. One of 7 patients achieved complete response, and 6 of 7 patients achieved partial response. No recurrence was noted with the median follow-up period of 6 months.

CONCLUSION

HMF could occur in young patients, with indolent and benign course. HMF could gradually seem as scaly erythema based on hypopigmented patches. The histopathology indicated a more advanced stage of the scaly erythema lesions than hypopigmented patches.

Hypopigmented Mycosis Fungoides: Loss of Pigmentation Reflects Antitumor Immune Response in Young Patients

Hypopigmented mycosis fungoides (HMF) is a form of cutaneous T-cell lymphoma (CTCL), a heterogeneous group of extranodal non-Hodgkin's lymphomas. HMF has a unique set of defining features that include light colored to achromic lesions, a predilection for darker skin phototypes, an early onset of disease, and predominance of CD8⁺ T-cells, among others. In the current review, we detail the known pathways of molecular pathogenesis for this lymphoma and posit that an active Th1/cytotoxic antitumor immune response in part explains why this variant is primarily seen in children/adolescents and young adults, who do not exhibit signs of immunosenescence. As a result of this potent cytotoxic response, HMF patients experience mostly favorable overall prognosis, while hypopigmentation may in fact represent a useful surrogate marker of cytotoxic immunity targeting the malignant cells. Understanding the molecular processes behind the specific features that define HMF may lead to improved diagnostic accuracy, personalized prognosis by risk stratification, and improved management of HMF. Moreover, improving our knowledge of HMF may aid our further understanding of other cutaneous lymphomas.

Ki67 and CD31 Differential Expression in Cutaneous T-Cell Lymphoma and Its Mimickers: Association with Clinicopathological Criteria and Disease Advancement

BACKGROUND

Cell proliferation and angiogenesis are important in progression of cancerous processes. Differentiating cutaneous T-cell lymphoma (CTCL) from its mimicking dermatoses and prognosticating it are challenging.

AIM

This study assesses cell proliferation and angiogenesis in different CTCL subtypes using immunohistochemistry (IHC) for Ki67 and CD31 to testify their usability in differentiating CTCL from mimicking dermatoses and discriminating CTCL subtypes from each other with correlation to clinicopathological parameters and disease advancement.

PATIENTS AND METHODS

IHC for Ki67 and CD31 were applied to skin biopsies from 81 patients divided into CTCL (n=59) and dermatoses (n=22) groups. Hot-spot analysis was used to score Ki67 and CD31 microvascular density (MVD) semiquantitatively. Statistical analysis was performed to compare Ki67 index and MVD between CTCL and dermatoses. CTCL subgroups were compared to each other. Ki67 index and CD31 were compared to age, gender, skin and nodal involvement, blood tumor burden and TNMB stage.

RESULTS AND CONCLUSION

There were significant differences in proliferation index and MVD between dermatoses and CTCL, and between dermatoses and all CTCL subtypes with exception of Ki67 in early mycosis fungoides (MF) and CD31 in patch lesions. Increased cell proliferation and MVD were significantly associated with older age, T3 and 4 skin involvement, significant nodes (N1-3), positive blood tumor burden (B1,2) in CTCL and TNMB stage of MF. Both markers differentiated significantly late from early MF, classic MF from its variants and non-MF CTCL from total MF, but not from late MF. In conclusion, Ki67 and CD31 expression in skin biopsies using IHC reproduces the role of proliferation and angiogenesis in the differential diagnosis and prognostication of CTCL being expressed at higher levels in aggressive than indolent CTCL. Therapeutic targeting of cell proliferation and angiogenesis may improve patient's outcome in CTCL. Usability of these markers into patient's stratification should be considered in further studies.

Thymocyte selection-associated high-mobility group box as a potential diagnostic marker differentiating hypopigmented mycosis fungoides from early vitiligo: A pilot study

BACKGROUND

Hypopigmented mycosis fungoides is a rare variant of mycosis fungoides that may mimic many benign inflammatory hypopigmented dermatoses, and as yet there is no identified marker to differentiate between them.

AIM

The aim of this study was to study the expression of thymocyte selection-associated high-mobility group box (TOX) in hypopigmented mycosis fungoides and one of its inflammatory mimickers (early active vitiligo) to assess its potential as a differentiating diagnostic marker.

METHODS

A case-control study was done using immunohistochemical analysis of TOX expression in 15 patients with hypopigmented mycosis fungoides and 15 patients with early active vitiligo. Immunohistochemical analysis was done via a semi-quantitative method and an image analysis method.

RESULTS

Hypopigmented mycosis fungoides showed a statistically significant higher expression of TOX than early active vitiligo. The expression of TOX was positive in a majority of hypopigmented mycosis fungoides cases (14 cases, 93.3%), while only one case (6.7%) of vitiligo was weakly positive. TOX also displayed 93.3% sensitivity and specificity, with a cut-off value of 1.5.

LIMITATIONS

This was a pilot study testing hypopigmented mycosis fungoides against only a single benign inflammatory mimicker (early vitiligo). Other benign mimickers were not included.

CONCLUSION

Our findings showed that TOX expression can differentiate hypopigmented mycosis fungoides from early active vitiligo which is one of its benign inflammatory mimickers, with a high degree of sensitivity and specificity.

Acquired disorders with hypopigmentation: A clinical approach to diagnosis and treatment

Acquired hypopigmented skin changes are commonly encountered by dermatologists. Although hypopigmentation is often asymptomatic and benign, occasional serious and disabling conditions present with cutaneous hypopigmentation. A thorough history and physical examination, centered on disease distribution and morphologic findings, can aid in delineating the causes of acquired hypopigmented disorders. The second article in this 2-part continuing medical education series focuses on conditions with a hypopigmented phenotype. Early diagnosis and appropriate management of these disorders can improve a patient's quality of life, halt disease progression, and prevent irreversible disability.

Hypopigmented Interface T-Cell Dyscrasia and Hypopigmented Mycosis Fungoides: A Comparative Study

Hypopigmented interface T-cell dyscrasia (HITCD) is a distinct form of lymphoid dyscrasia that may progress to hypopigmented mycosis fungoides (HMF). We compared both diseases as regards their CD4/CD8 phenotype and expression of granzyme B and tumor necrosis factor-alpha (TNF-α) and how these are affected by narrow-band UVB (nb-UVB). The study included 11 patients with HITCD and 9 patients with HMF. They received nb-UVB thrice weekly until complete repigmentation or a maximum of 48 sessions. Pretreatment and posttreatment biopsies were stained using anti CD4, CD8, TNF-α, and granzyme B monoclonal antibodies. Epidermal lymphocytes were CD8 predominant in 54.5% and 66.7% of HITCD and HMF cases, respectively, whereas dermal lymphocytes were CD4 predominant in 63.6% and 66.7%, respectively. Significantly, more dermal infiltrate was encountered in HMF (P = 0.041). In both diseases, granzyme B was only expressed in the dermis, whereas TNF-α was expressed both in the epidermis and dermis. No difference existed as regards the number of sessions needed to achieve repigmentation or cumulative nb-UVB dose reached at end of study. (P > 0.05). Narrow-band UVB significantly reduced only the epidermal lymphocytes in both diseases (P ≤ 0.05) with their complete disappearance in 8 (72.7%) HITCD and 6 (66.7%) HMF cases. In both diseases, nb-UVB did not affect granzyme B or TNF-α expression (P > 0.05). In conclusion, both diseases share the same phenotype, with HITCD being a milder form of T-cell dysfunction. In both diseases, epidermal lymphocytes are mainly CD8-exhausted cells lacking cytotoxicity, whereas dermal cells are mostly reactive cells exerting antitumor cytotoxicity. Tumor necrosis factor-alpha mediates hypopigmentation in both diseases and prevents disease progression. Repigmentation after nb-UVB in both diseases occurs before and independently from disappearance of the dermal infiltrate.

Cutaneous Lymphomas with Cytotoxic Phenotype

Primary cutaneous cytotoxic lymphomas are T-cell or natural killer-cell lymphomas that express 1 or more cytotoxic markers. These neoplasms constitute a spectrum of diseases. In this review, an overview of clinical, morphologic, and phenotypical features of each subtype is provided. Differential diagnosis is discussed with attention to scenarios in which diagnostic difficulties are most frequently encountered.