Primary Cutaneous Gamma-delta T-cell Lymphoma Research Articles

Abstract 813: Primary cutaneous gamma-delta T-Cell lymphoma in the United States: A nationwide analysis of demographics and survival outcomes among the Hispanic population

Abstract BACKGROUND: Primary Cutaneous Gamma-Delta T-Cell Lymphoma (PCGDTCL) is a rare subtype of cutaneous T-cell lymphoma (CTCL) that, despite comprising <1% of cutaneous lymphomas, has gained recognition in recent years as an entity separate from other rare CTCLs. (LeukemiaPMID 35732829) A 5 year survival of 11% demonstrates a low response to current available therapies. (BloodPMID 30635287, Clin Hematol Int.PMID 35950208) Due to lack of consistency in behavior between CTCLs, there exists a need for studies of demographic, clinical, and survival disparities, including between Hispanics (HI) vs. non-Hispanics (NH). METHODS: Data were analyzed on PCGDTCL patients in the United States reported to the National Cancer Database (NCDB) between 2004-2019. Demographic and treatment characteristics were compared between ethnic groups. Kaplan-Meier and Cox regression analyses were used to compare OS between populations. Multivariate analysis and propensity score matching was performed with adjustment for age, stage, co-morbidity score, and insurance status, type of facility and great circle distance. RESULTS: Among 132 PCGDTCL patients studied (5% HI, 92% NH), the HI group was younger at diagnosis than NH (49.5y vs. 60y) (p=0.384); The majority of HI (50%) was diagnosed between 2010-2012 vs 2017-2019 for NH (45%) (p=0.673). Most of HI and NH were white (67% vs 79%). Private insurance was the most prevalent type in HI (67%) vs government sponsored for NH (49%). The most non-Insured group was NH (3%) vs HI (0%). The most prevalent bracket for Census Median Income (2008-2012) was $63,000+ for both HI (50%) and NH (31%). 17% HI vs 13%. NH had median income <$38,000. For Charlson-Deyo Score (comorbidities score), HI had 0% =/> 2 score, vs NH 6%. NCI-designated comprehensive cancer centers were the most prevalent type of facility providing care for HI (100%) and NH (56%) Survival probability (OS) at 2, 5 and 10y (HI vs NH) were (80% vs 48%), (80% vs 44%), and (80% vs 26%), respectively. Median survival time (MS) was not reached for HI vs 1.9 years for NH. Overall survival (OS) difference favored HI (p=0.13) On multivariate analysis, there was no independent variable associated with better or worse OS. Interestingly, the propensity matched analysis demonstrated significant MS difference between HI vs NH (median not reached vs. 1.35 years). CONCLUSION: There was no significant difference in OS between groups; however, the weighed MS favored the HI cohort, likely in part due to the difference in numbers between cohorts. The drastically low survival in all demographics is consistent with prior studies. These results demonstrate an unmet need for more comprehensive studies with the potential inclusion of correlatives looking at intrinsic biologic characteristics that may offer insight into druggable targets, aiming for improvement in survival outcomes for this rare lymphoma. Citation Format: Katherine Thiel, Rosa White, Qianqian Liu, Joel Michalek, Adolfo Enrique Diaz Duque. Primary cutaneous gamma-delta T-Cell lymphoma in the United States: A nationwide analysis of demographics and survival outcomes among the Hispanic population [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 813.

A Rare Case of Primary Cutaneous Gamma-Delta T-cell Lymphoma with Aberrant B-cell Marker Expression.

Primary cutaneous gamma-delta T-cell lymphoma (PCGDTL) is a rare and diagnostically challenging primary skin lymphoma. We present a case of a 78-year-old otherwise healthy man who developed nonhealing nodules on his right posterior calf. Initial biopsy showed a dense, atypical, lymphoid infiltrate with gamma-delta and cytotoxic T-cell immunophenotypes. The diagnosis of PCGDTL was rendered; however, concurrent flow cytometry revealed expression of aberrant B-cell markers, including CD19 and cytoplasmic CD79a. Subsequent immunohistochemical studies corroborated this result. We report the extremely rare phenomenon of aberrant B-cell marker expression in PCGDTL, the first formally reported case to our knowledge.

Descriptive Analysis and Factors Influencing Survival in Patients With Primary Cutaneous Gamma-Delta T Cell Lymphoma. A Retrospective National Cancer Database Study.

BackgroundGamma delta T cells gives rise to a rare malignancy called Primary cutaneous Gamma-Delta T cell lymphoma (PCGDTCL). MethodsFrom the National Cancer Database (NCDB), 110 (0.015%) patients with PCGDTCL were identified. ResultsMales aged >60 years were the commonest cohort. Caucasian race was the most common (Caucasian: 79.09%, African American:16.36%). Most patients were diagnosed at stage 1 (52.33%), followed by stage 4 (30.23%). On analyzing income categories, <$48,000 group had 48.15% stage 4 (13/27) and 40.74% (11/27) stage 1. Overall survival (OS) of the study group at 3 years by Kaplan-Meier (KM) analysis was 46.6%. African American race (37.5%), income of <$48,000 (27.6%) and government insurance (38.8%) had lower survival rates in KM analysis. In the adjusted hazard ratio (HR) analysis, only age <=40 years compared to >60 years (0.165 [0.036, 0.768], P= .0217) reached significance. Although the group that did not receive any chemotherapy or radiation seemed to have a better survival by KM analysis at 74.3% at 3 years, significance was not seen in the adjusted HR estimates and majority of the patients in this group were stage 1. This group may have received topical treatments which may have not been captured in NCDB. Adjusted analysis also revealed chemoradiation to have a lower mortality risk compared to chemotherapy alone (0.229 [0.079, 0.670], P = .0071), suggesting that aggressive strategies may be required for management when needed. ConclusionSocioeconomic disparities significantly impact access to healthcare and are of particular importance in rare lymphomas.

499 - The Impact of Stem Cell Transplant on Clinical Outcomes of Primary Cutaneous Gamma-Delta T-Cell Lymphoma, Primary Cutaneous CD8+ Aggressive Epidermotropic Cytotoxic T-Cell Lymphoma, and Subcutaneous Panniculitis-like T-Cell Lymphoma: Analysis of Pooled Databases of Rare Cutaneous Extra-Nodal T-Cell Lymphoma Entities

499 - The Impact of Stem Cell Transplant on Clinical Outcomes of Primary Cutaneous Gamma-Delta T-Cell Lymphoma, Primary Cutaneous CD8+ Aggressive Epidermotropic Cytotoxic T-Cell Lymphoma, and Subcutaneous Panniculitis-like T-Cell Lymphoma: Analysis of Pooled Databases of Rare Cutaneous Extra-Nodal T-Cell Lymphoma Entities

Demographic Features, Clinical Characteristics and Survival Outcomes of Primary Cutaneous Gamma-Delta T Cell Lymphoma, a Retrospective National Cancer Database Analysis

Introduction The cytotoxic gamma delta T cells give rise to an extremely rare malignancy, known as Primary cutaneous Gamma-Delta T cell lymphoma (PCGDTCL), which represents < 1% of all lymphomas. These are considered aggressive lymphomas with a median survival of 15-31 months. Since they usually present as plaques in the extremities, they mimic nonspecific panniculitis and need a high index of suspicion for diagnosis. Using a large national cancer repository, the National Cancer Database (NCDB), we analyzed the demographic distribution, clinical characteristics, treatment strategies and survival outcomes and studied the impact of various factors on the survival of patients with PCGDTCL. Methods The 2004-2018 NCDB file was used to extract patients with a diagnosis of PCGDTCL. We included patients who had skin and lymph nodes as the primary disease sites. All patients were adults aged ≥ 18 years. Frequencies and chi-square tests were used to compare patient distribution among various demographic and clinical characteristics as shown in the table. Kaplan-Meier (KM) analysis and hazard ratios (HR) were used to compare survival outcomes. Results A total of 110 patients with PCGDTCL were identified. The table summarizes the distribution of patients by various demographic features and disease stage. The median age of our cohort was 58 years. Most of the patients were elderly males aged >60 years (>60 years: 42.73%, 41-60 years: 36.36%, <=40 years: 20.91%) (Males: 56.36%, Females: 43.64%). Caucasian race was the most common (Caucasian: 79.09%, African American: 16.36%). There was an equal distribution of patients using private and government insurance (48.18% each). Income, facility type, and area distribution is shown in the table. Most of the patients were diagnosed at stage 1 (52.33%), followed by stage 4 (30.23%). 55.88% (38/68) of Caucasians were diagnosed at stage 1 and 27.94% (19/68) were diagnosed at stage 4. Among African Americans, the distribution between stage 1 and stage 4 was 38.46% (5/13) each. On analyzing income categories, <$48,000 group had 48.15% stage 4 (13/27) and 40.74% (11/27) stage 1. Among the >=$48,000 group, 57.88% (26/45) were stage 1 and 24.14% (11/45) were stage 4. Distribution by insurance used is shown in the table. The distribution among various systemic treatment strategies used were as follows: Chemotherapy only - 47 (42.72%), Chemotherapy with Radiation - 17 (15.46%), Radiation alone -13 (11.82%), No chemotherapy or Radiation - 33 (30%). Among patients who did not receive chemotherapy or radiation, 79.17% had stage 1 disease. Overall survival of the study group at 3 years was 46.6%. The group that did not receive chemotherapy or radiation had the highest 3-year survival (74.3%). Survival rates of the other treatment groups and the survival by race, income and insurance is represented in the table. HR estimates showed that compared to the no systemic therapy group, the chemotherapy [2.994 (95% CI 1.400, 6.401)p=0.0047] and chemotherapy with radiation [2.611 (95% CI 1.048,6.5090)p=0.0394] groups had more adverse outcomes. Comparison between the other treatment groups were not significant. The African American race had a lower overall survival (37.5%), but the HR did not reach significance compared to Caucasians [1.524 (95% CI 0.779,2.984)p=0.2187]. Having an income of <$48,000 had a lower survival (27.6%) with HR [2.151 (95% CI 1.225,3.778)p=0.0077] compared to the higher incomes. Government insurance had a lower survival (38.8%), but the HR did not show significance compared to private insurance [1.708 (95% CI=0.980, 0.977)p=0.0591]. Conclusion We provide one of the first descriptive analysis of a very rare lymphoma. Although the group that did not receive any chemotherapy or radiation had better survival, majority of the patients in this group were stage 1. We hypothesized that this group may have received topical treatments which may have not been captured in NCDB. Socioeconomic disparities significantly impact access to healthcare and is of particular importance in rare lymphomas like PCGDTCL. In our analysis, patients with a lower income had a worse survival. The survival was also lower among African Americans, although the HR was not significant. A higher percentage of African American patients and those with a lower income were also diagnosed at Stage 4. Limitations of our study include the use of non-population-based data and the confounding that may arise from it. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Clinical Characteristics, Treatment Patterns, and Outcomes of Cytotoxic Cutaneous T-Cell Lymphomas

Introduction Cytotoxic cutaneous T-cell lymphomas (CCTCLs) are an uncommon group of neoplasms defined by expression of at least one cytotoxic marker (e.g. TIA-1, granzyme B, or perforin). Due to their rarity, comparatively little is known about their presentation and overall course. Here, we present a detailed retrospective experience of patients with CCTCLs, focusing on their clinicopathologic and molecular characteristics, treatment details, and survival outcomes. Methods The Stanford University Cutaneous Lymphoma Database was queried to gather data on patients with CCTCLs seen between 1995-2020, including the following diagnoses: subcutaneous panniculitis-like T-cell lymphoma (SPTCL), primary cutaneous gamma-delta T-cell lymphoma (PCGDTCL), primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma (PCAECTCL), and unclassified CCTCLs (CCTCL-NOS). Clinical and laboratory data, including clinical suspicion of hemophagocytic syndrome (HPS), were extracted from the electronic medical record. Treatment data were recorded, including use of radiotherapy (RT), pralatrexate, romidepsin, brentuximab vedotin (BV), combination chemotherapy, allogeneic stem cell transplant (allo-SCT), and others. We evaluated time to next treatment (TTNT), calculated as the start date of one line of therapy to the start date of next line of therapy, in addition to overall survival (OS) and factors predictive of outcome. A subset of patients was evaluated with a clinically validated high-throughput sequencing panel for hematopoietic and lymphoid neoplasms (Heme-STAMP) covering 164 genes. Results 46 patients were included: 22 (47.8%) SPTCL, 13 (28.2%) PCGDTCL, 3 (6.5%) PCAECTCL, and 8 (17.3%) CCTCL-NOS. Mean age at diagnosis was 55.7 years (range: 14.9 - 87.4). Most patients (87%) presented with generalized skin lesions, while involvement of lymph nodes (22.2%), viscera (8.9%), or bone marrow involvement (3.1%) were uncommon. Clinical suspicion for HPS was noted in 23 (50%) patients. Median lines of therapy received was 2.5 (range: 1-12). Median TTNT (mTTNT) from first-line therapy was 8.5 months, second-line 5.3 months, and third-line 7.8 months. Variation in mTTNT was observed between CCTCL subtypes. In patients with SPTCL, mTTNT from first and second-line therapy were 10.2 and 24.0 months, respectively. In patients with PCGDTCL, mTTNT after first-line therapy was 11.1 months, decreasing sharply thereafter (0.5-3.1 mo. for 2nd-5th lines). Patients with PCAECTCL had short mTTNT of less than 3 months for all lines of treatment. Patients with CCTCL-NOS exhibited more heterogeneity (mTTNT 2.9 - 9.1 mo. for 1st-5th lines). The most commonly used treatments were combination chemotherapy (n=24 instances, mTTNT 7.2 mo.), pralatrexate (n=18, mTTNT 11.6 mo.), romidepsin (n=17, mTTNT 2.4 mo.), RT (n=16, mTTNT 3 mo.), and BV (n=11, mTTNT 3.7 mo.). Median TTNT varied between CCTCL subtypes and was generally longest in patients with SPTCL. 2- and 5-year OS were 73.5% and 64.2%, respectively. Significant differences were observed between CCTCL subtypes (Figure 1).Age > 60 was associated with worse survival (2-year OS 42.3% vs. 100%, p < .0001). Extracutaneous involvement was not associated with outcome (2-year OS 60.6% vs. 69.1%, p=0.5), nor was documented clinical suspicion for HPS (2-year OS 82.2% vs. 64.8%, p=0.21). Patients undergoing allo-SCT (n=9) had superior OS (2-year OS 100% vs. 66.1%, p=0.03) (Figure 2). Thirteen (28.3%) patients had data available from Heme-STAMP testing; every patient who underwent testing had at least one identified mutation. The most frequently occurring somatic mutations included TP53 (n=3), TERT (n=3), and JAK1 (n=3). Conclusions CCTCLs are rare entities with heterogeneous presentation, response to therapy, and survival. Chemotherapy remains an effective treatment, and we identify pralatrexate as a promising single agent option. Allo-SCT offers curative potential in eligible patients. Given wide variation in disease behavior, treatment intensity should be tailored to each individual's clinical phenotype to optimally balance risk and benefit. Further efforts to define the molecular basis of CCTCLs are urgently needed to aid in the identification of more effective therapies. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Primary Cutaneous Gamma-Delta T-Cell Lymphoma (PCGDTCL) Descriptors and Clinicopathologic Determinants of Survival: Analysis of a Pooled Database

Introduction Primary Cutaneous Gamma-Delta T-cell Lymphoma (PCGDTL) is a rare clinical entity that represents <1% of all cutaneous lymphomas. It is characterized by clonal proliferation of mature, activated T-cells expressing the T-cell receptor (TCR) γ/δ and cytotoxic molecules. PCGDTL is often resistant to conventional chemotherapy and is usually associated with poor prognosis. We have conducted this pooled database analysis to delineate key disease characteristics and clinicopathologic determinants of survival in this rare cutaneous T-cell lymphoma. Methods To study the demographic characteristics, molecular and immunohistochemical signatures, therapeutic interventions, survival, and prognostic factors, we compiled a pooled database of 140 cases. Kaplan-Meier survival curves were constructed. Cox proportional-hazards model and Log-rank tests were used to assess the influence of demographic and clinicopathologic factors on overall survival (OS). Results A total of 140 patients with confirmed PCGDTCL were identified. The median age was 54 years with peak incidence between ages 52 and 65 years. There was no sex preponderance. The median duration of symptoms prior to diagnosis was 9 months. Eighty percent of patients presented with >4 lesions with an average size of 3.4cm. The disease involved mostly the lower extremities followed by the upper extremities, trunk, and lastly the face. Almost all the lesions involved the dermis with 48% involving the epidermis. Twenty-four percent of the lesions presented with ulceration and 30% had fat necrosis. Patients presented with constitutional symptoms in 28%, splenomegaly 6%, lymphadenopathy 16%, and hemophagocytic syndrome (HPS) 13%. Compared to no treatment, combination chemotherapy and stem cell transplant (SCT) were statistically superior with median OS months of 2, 16, and not reached respectively (p<0.0001). Age inversely correlated with survival while time from symptoms to diagnosis has a positive correlation. CD30+ imparted a survival advantage while HPS was detrimental to OS, both at borderline significance. Visceral involvement was also associated with a worse median OS (9.5 vs 18 months). OS was not impacted by sex, size of the lesions, or subcutaneous involvement. While solitary disease and absence of constitutional symptoms and bone marrow involvement seemed to have better OS, they did not reach statistical significance. Conclusions This study presents an updated clinicopathologic data from a pooled cohort of patients with PCGDTCL. It details the features of this rare disease and identifies the clinical, immunohistochemical, and treatment modalities that are major determinants of OS.

Hist-PO-03 - Primary cutaneous gamma-delta T-cell lymphoma: a devastating malignancy in wolf’s clothing in 13 patients

Hist-PO-03 - Primary cutaneous gamma-delta T-cell lymphoma: a devastating malignancy in wolf’s clothing in 13 patients

A Registry-Based Geodemographic Assessment of Non-Hodgkin Lymphoma Subtypes in North Carolina

Background: Non-Hodgkin lymphoma (NHL) is the most common hematologic malignancy in the United States. NHL comprises a heterogeneous group of over 40 histological subtypes, each of which has distinct genetic, morphologic and clinical features. While NHL epidemiology as a single entity has been well-characterized using population-based cancer registry data, the epidemiology of NHL subtypes is not well understood and even less data are available for rarer subtypes. We aimed to determine geodemographic correlates for NHL subtypes in North Carolina to provide rarely reported epidemiologic characterization of each distinct malignancy.Methods: Demographic data were obtained on all NHL subtypes reported in persons >18 years of age from 2009-2019 from the North Carolina Central Cancer Registry (NCCCR). NHL subtypes were determined based on World Health Organization International Classification of Diseases for Oncology,Third Edition (ICD-O-3) Morphology codes provided by NCCCR. Crude incidence and mortality rates were estimated per 100,000 persons for the 10-year period using 2019 population data from the U.S Census Bureau. Urban and rural residence designations were based on zip code using rural-urban commuting codes developed by the Rural Health Research Center. County tier designations were used as markers of economic prosperity, with 3 being most prosperous, and provided by the North Carolina Department of Commerce. Data are being mapped using ESRI ArcMap 10.8.1.Results: A total of 25,627 incident cases of NHL and 9,930 associated deaths were reported between 2009 and 2019 in North Carolina. Therefore, the standard NHL incidence and mortality rates are 24.1 and 9.3 per 100,000 persons. For incident NHL cases, median age at diagnosis was 68 years (range 19-103), 55% were male and 45% female. Most (83%) identified as white, 14% as black, and 3% as other. Median age at death was 70 years (range 19-106). Twenty-eight NHL subtypes were identified with the four most common NHL subtypes being Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma (CLL/SLL), Diffuse Large B Cell Lymphoma (DLBCL), Follicular Lymphoma (FL), and Marginal Zone Lymphoma with 6.54, 6.42, 3.55, and 2.0 cases (per 100,000 persons), respectively. Least common subtypes included Intravascular Large B Cell Lymphoma, Primary Effusion Lymphoma, Primary Cutaneous Gamma Delta T-cell Lymphoma (PCGD-TCL) and Subcutaneous Panniculitis-Like T-cell Lymphoma, all with 0.01 cases per 100,000 persons (or 15, 14, 9 and 6 cases respectively). The distribution of NHL subtypes varied according to demographics with several notable findings. DLBCL had the highest crude mortality rate of 2.98 deaths/100,000 persons, followed by CLL (2.12 deaths/100,000 persons), FL (0.98 deaths/100,000 persons) and Lymphoma NOS (0.51 deaths/100,00 persons). Mediastinal Large B-cell Lymphoma (MLBCL) was diagnosed in the youngest individuals with median age of 36 (range 20-74), whereas PCGD-TCL occurred in the oldest with median age of 74 (range 31-99). Primary Effusion Lymphoma had the highest male predominance (93%) and MLBCL had the highest female predominance (73%). Mantle Cell Lymphoma had the highest predominance of persons who identify as white (90%), Anaplastic Large Cell Lymphoma (ALK+/-) with those who identify as black (66%), and Primary Effusion Lymphoma with those who identify as other (14%). Predominance of rurality and county tier designations varied by NHL subtype.Conclusions: A registry-based assessment of NHL subtypes illustrates the heterogeneous nature of this group of malignancies and highlights significant variation in the geodemographic features of each subtype. Evaluating geodemographic correlates deepens our understanding of NHL subtypes and can inform populations at risk for each unique NHL subtype. [Display omitted] DisclosuresDittus: BeiGene: Other: Advisory Board; Seattle Genetics: Research Funding; AstraZeneca: Research Funding; Genentech: Research Funding.

High incidence of adnexotropism in cytotoxic cutaneous lymphomas

Primary cutaneous gamma-delta T-cell lymphoma (PCγδTCL) and primary cutaneous aggressive epidermotropic T-cell lymphomas (PCAETCL) are rare aggressive cytotoxic cutaneous lymphomas (CyCL) often difficult to diagnose. Histopathologically, PCAETCL and PCγδTCL may resemble mycosis fungoides (MF) and the presence of adnexotropism in CyCL (CyCL) contributes to this diagnostic challenge, especially in the setting of atypical and double-negative phenotypes. In this retrospective study clinical data and histopathological section of 91 patients were analyzed for signs of clinical and histopathological signs adnexotropism. Adnexotropism was identified in 48.4% (44/91) of cases, including PCAETCL (40.9%, 18/44), PCγδTCL and cytotoxic cutaneous lymphomas, not otherwise specified (CyCTCL, NOS) (43.2%, 19/44 and 15.9%, 7/44). Comparison between disease-related mortality with Kaplan-Meier survival analysis of non-adnexotropic vs adnexotropic CyCL did not show any significant difference between the two groups (P=0.8). Clinically they present with patches, plaques, and tumors and commonly with ulceration, but follicular prominence or alopecia are rare. Clinical signs of adnexotropism such as alopecia and hypo- or anhidrosis were rarely seen. Adnexotropism is a common finding in CyCL, especially in PCAETCL. Adnexotropic CyCL may be histopathologically difficult to distinguish from folliculotropic mycosis fungoides. A comprehensive IHC panel should be routinely performed in such cases.

Primary cutaneous gamma-delta T-cell lymphoma: Two cases and a review of the literature

Background: Primary cutaneous gamma delta T cell lymphoma (PCGD TCL) is a rare and rapidly progressive cutaneous malignancy that can be diagnostically challenging. Purpose: To improve characterization of the clinical and histologic features of PCGD-TCL. Methods: We present two patients with PCGD TCL and review an additional 97 PCGD TCL cases from the English literature. Results: A 51 year old male with biopsy proven psoriasis and a previously healthy 31 year old male with vitiligo developed PCGD-TCL. Initial biopsy specimens in both patients suggested tumor stage mycosis fungoides (MF), but subsequent histopathology confirmed PCGD TCL. Ninety-seven patients were identified in the literature, mostly males (53%) with a mean age of 55.2 years. Lesions most commonly involved the lower (60%) and upper (30%) extremities and existed a mean of 26 months before diagnosis. The most common immunohistochemical markers were EBV(-), CD3(+), CD4(-), CD5(-), CD7(-), CD8(-), CD30(-), CD56(+), granzyme-B(+), perforin(+), and βF1(-). Radiation and CHOP chemotherapy were the most common interventions and 52% of patients died. Conclusion: PCGD TCL is a devastating disease that can clinically and histologically mimic more common dermatologic conditions, such as psoriasis and MF, and its diagnosis may require multiple biopsies and review by a multi specialty pathology team.

Comparative Transcriptomics of Alpha-Beta Subcutaneous Panniculitis-like T-Cell Lymphoma and Primary Cutaneous Gamma Delta T-Cell Lymphoma

Background: Subcutaneous lymphomas are a heterogeneous group of diseases with variable clinical behavior that ranges from a lymphoproliferative disorder to an aggressive cytotoxic lymphoma. Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is an uncommon, often indolent cutaneous lymphoma that localizes to the subcutaneous adipose tissue. These tumors exhibit an alpha/beta phenotype (abSPTCL). Primary cutaneous gamma-delta T-cell lymphoma (PCgdTCL) is a rare, highly aggressive lymphoma that frequently involves the subcutaneous adipose tissue. The goal of this study is to identify key inflammatory and oncogenic pathways in SPTCL and PCgdTCL to determine which mutational or expression patterns differentiate abSPTCL and PCgdTCL. A comprehensive catalog of cancer gene expression profiles generated via RNA sequencing on patient samples is essential to understand tumorigenesis and to develop effective therapies. Methods: We performed transcriptomic profiling analysis using RNA sequencing in lesional skin biopsies from patients of abSPTCL (n=10), PCgdTCL (n=9), and controls (n=5). Differential analyses were performed on the entire transcriptomic profiles among the 3 groups. Results: Although the transcriptomic profiles of abSPTCL and PCgdTCL samples had similarities, there were notable differences between these groups that may elucidate unique pathways that propagate each disease. In contrast to abSPTCL, PCgdTCL samples demonstrated upregulation of cell motility and proliferation, and downregulation of pathways involving apoptosis and tumor necrosis factor production. The most significantly upregulated gene pathways in both abSPTCL and PCgdTCL samples were those involving immune and inflammatory response, viral defense, type I interferon signaling, interferon-gamma-mediated signaling, and positive regulation of T cell proliferation. The most significantly downregulated gene pathways in the two groups were those involving cell adhesion, rRNA processing and translation, and extracellular matrix organization. The top 5 upregulated immune response and downregulated cell adhesion hub genes for abSPTCL highlighted by gene interaction network analysis included: TNF, CTLA4, CD86, IL10, CCR5 &amp; ITGB5, ITGA8, VWF, APP, CDH5, respectively. Conclusion: Our transcriptomic profiling pinpoints disease-related enrichment pathways and gene functions in abSPTCL and PCgdTCL patients, which may shed light on molecular mechanisms that drive disease activity. Hub genes in abSPTCL represent potential drug targets for further development of novel therapies. Disclosures Mangold: Kirin:Membership on an entity's Board of Directors or advisory committees;Elorac:Research Funding;Sun Pharma:Research Funding;MiRagen:Research Funding;Solagenix:Research Funding.

Characteristics, Treatment Patterns, and Outcomes in Primary Cutaneous Gamma Delta T Cell Lymphoma (PCGDTCL): A Real World Multi-Institutional Analysis of a Rare Malignancy

Characteristics, Treatment Patterns, and Outcomes in Primary Cutaneous Gamma Delta T Cell Lymphoma (PCGDTCL): A Real World Multi-Institutional Analysis of a Rare Malignancy

Primary cutaneous gamma-delta T-cell lymphoma masquerading as severe soft tissue infection

N/A- Case report

Volumetric Modulated Arc Therapy and 3-Dimensional Printed Bolus in the Treatment of Refractory Primary Cutaneous Gamma Delta Lymphoma of the Bilateral Legs

Primary cutaneous gamma-delta T-cell lymphoma (PCGDTL) is an aggressive subtype that comprises <1% of cutaneous T-cell lymphomas. 1 Guitart J. Weisenburger D.D. Subtil A. et al. Cutaneous γδ T-cell lymphomas: A spectrum of presentations with overlap with other cytotoxic lymphomas. Am J Surg Pathol. 2012; 36: 1656-1665 Google Scholar , 2 Phan A. Veldman R. Lechowicz M.J. T-cell lymphoma epidemiology: The known and unknown. Curr Hematol Malig Rep. 2016; 11: 492-503 Google Scholar , 3 Foppoli M. Ferreri A.J.M. Gamma-delta t-cell lymphomas. Eur J Haematol. 2015; 94: 206-218 Google Scholar Deep dermal and subcutaneous lesions are common and may be necrotic or ulcerated. 4 Tripodo C. Iannitto E. Florena A.M. et al. Gamma-delta T-cell lymphomas. Nat Rev Clin Oncol. 2009; 6: 707-717 Google Scholar Radiation therapy (RT) is an effective treatment for patients with localized PCGDTL, using doses from 30 to 36 Gy. However, RT poses a challenge for patients with widespread subcutaneous disease because irradiating the core of limbs increases the risk of lymphedema, vascular leakage, and fibrosis. 5 El-Bared N. Wong P. Wang D. Soft tissue sarcoma and radiation therapy advances, impact on toxicity. Curr Treat Options Oncol. 2015; 16: 19 Google Scholar Techniques such as total skin electron beam therapy do not adequately penetrate to the depth of subcutaneous PCGDTL lesions: degraded 9 MeV electrons, 80% dose at 0.7 cm, and 50% dose at 1.25 cm. 6 Hoppe R.T. Mycosis fungoides: Radiation therapy. Dermatol Ther. 2003; 16: 347-354 Google Scholar , 7 Chinn D.M. Chow S. Kim Y.H. Hoppe R.T. Total skin electron beam therapy with or without adjuvant topical nitrogen mustard or nitrogen mustard alone as initial treatment of T2 and T3 mycosis fungoides. Int J Radiat Oncol Biol Phys. 1999; 43: 951-958 Google Scholar Volumetric modulated arc therapy (VMAT), a form of intensity modulated radiation therapy, is an effective technique to treat circumferential surfaces while sparing the inner body. 8 Servy A. Kramkimel N. Franck N. Park S. Kirova Y.M. Helical tomotherapy in oncodermatology: Case report of circumferential cutaneous lymphoma treated by this optimized radiotherapy. Cancer Radiother. 2014; 18: 136-138 Google Scholar A reproducible bolus that covers extended irregular surfaces would simplify setup and minimize air gaps that can cause dosimetric distortion. We present a patient with extensive bilateral leg involvement with PCGDTL who achieved remission after treatment with VMAT, using 3-dimensional printed bolus and positioning to irradiate each leg individually.

Silent T-cell receptor cutaneous T-cell lymphoma associated to a clonal plasma cell proliferation.

Within T-cell lymphomas (TCL) there are 2 entities expressing gamma-delta TCR: hepatosplenic gamma-delta T-cell lymphoma (HSGDTL) and the primary cutaneous gamma-delta T-cell lymphoma (PCGDTL). PCGDTL is a rare form of Tcell lymphoma with specific tropism for skin that have a dismal prognosis. Although even rarer, there have been reports of TCL with loss of expression of the TCR, which have been termed peripheral TCL TCR-silent type. We report the case of a cutaneous TCR-silent type lymphoma associated to a clonal plasma cell proliferation with an ominous outcome that led to a lot of discussion in its classification. Due to the aggressiveness of the disease and the scant evidence about therapy in this strange entity the outcome was fatal. We report a unique case of a TCR-silent cutaneous TCL with an exceptional histopathology, prolonged clinical evolution and a subsequent plasma cell clonal expansion.

Primary Cutaneous Gamma Delta T Cell Lymphoma: A Clinicopathological Analysis

Primary cutaneous gamma-delta T-cell lymphoma (PCGD-TCL) is a very uncommon and extremely aggressive tumor, and is described in the newly re-vised World health organization for research and treatment of cancer classification of cutaneous lymphomas. A 43-year-old male patient presented with a 4 months history of cutaneous lesion over upper lip, without plaque and any constitutional symptom. Histopathological examination of skin biopsy revealed infiltration of atypical lymphocytes with hyperchromatic irregular nuclei. Immunophenotyping pattern of skin biopsy was compatible with PCGD-TLC. It is a highly aggressive tumor resistant to chemotherapy, immunotherapy, and radiation therapy. The GDTCL is characterized by a worse prognosis with a median survival of 15 months. Early diagnosis is essential and aggressive therapy is necessary.

Primary cutaneous lymphomas: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up

Primary cutaneous lymphomas: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up

Primary Cutaneous T-Cell Lymphomas Showing Gamma-Delta (γδ) Phenotype and Predominantly Epidermotropic Pattern are Clinicopathologically Distinct From Classic Primary Cutaneous γδ T-Cell Lymphomas.

Primary cutaneous gamma-delta (γδ) T-cell lymphoma is a rare disease that typically involves the dermis and subcutis. Cases of primary cutaneous T-cell lymphomas showing γδ phenotype and predominantly epidermotropic pattern (EγδTCL) are not well defined. In this series, cases of primary cutaneous T-cell lymphomas showing γδ phenotype were reviewed and classified as predominantly epidermotropic (EγδTCL) when >75% of lymphoma cells resided in the epidermis or predominantly dermal and/or subcutaneous (DSγδTCL). Clinical, pathologic, and immunophenotypic features were compared in 27 biopsies from 13 patients of EγδTCL and 13 biopsies from 7 patients of DSγδTCL. The lymphoma cells were diffusely positive for CD3 and T-cell receptor (TCR)γ, mostly positive for granzyme B and TIA-1, variably positive for CD8, CD7, and CD30, and negative for CD4 and TCRβ. Two patients with EγδTCL had dissemination to lymph nodes and 1 to the lung; 1 patient with DSγδTCL had gastrointestinal involvement. The median survival of patients with EγδTCL was not reached, and with a median follow-up of 19.2 months, 3/13 died. In contrast, the median survival of patients with DSγδTCL was 10 months, and after a median follow-up of 15.6 months, 5/5 died (P<0.01). EγδTCL is a rare presentation of cutaneous T-cell lymphoma that can be distinguished from DSγδTCL based on the extent of epidermotropism and has a better prognosis and longer median survival than DSγδTCL. However, although EγδTCL resembles mycosis fungoides clinically and histologically, a subset of EγδTCL is more likely to behave more aggressively than typical mycosis fungoides.

Outcome of Patients with Peripheral T-Cell Lymphoma Undergoing Allogeneic Stem Cell in British Columbia

Background:Peripheral T-cell lymphomas (PTCL) are a rare and heterogeneous group of non-Hodgkin lymphomas (NHLs) that accounts for approximately 10% of all aggressive NHLs in Western countries. The optimal management remains unclear, however, given the poor outcome, allogeneic transplant (allo-SCT) has been integrated into the front-line treatment for some rare extranodal subtypes as well in relapsed/refractory setting. We report our provincial experience of the outcome of patients with PTCL who have undergone allo-SCT at the British Columbia Cancer Agency (BCCA).Methods:The Leukemia/BMT Program of British Columbia database and the BCCA Lymphoid Cancer Database were searched to identify all patients diagnosed with PTCL who have undergone allo-SCT between November 1990 and January 2016. Overall survival and relapse free survival were estimated using the Kaplan-Meier method.Results:We identified 36 cases of PTCL patients who have undergone allogeneic transplant from a median time of 11 months from primary diagnosis (range 4-64) with the following clinical features: median age at transplant was 45 years (range 16-58 years); 24 (67%) were male; 32 (89%) patients had advanced stage disease; 22 (61%) had B-symptoms at diagnosis. Bone marrow involvement detected in 13/34 (38%) patients. Histological diagnosis based on the WHO 2008 classification were: Peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) n=15 (42%); anaplastic large cell lymphoma (ALCL) n=7 (19%) out of which three were ALK positive, angioimmunoblastic T-cell lymphoma (AITL) n=6 (17%), hepatosplenic T-cell lymphoma n=5 (14%), enteropathy associated T-cell lymphoma type I n=1, advanced primary cutaneous gamma-delta T-cell lymphoma n=1 and Sezary syndrome n=1. Ten patients (28%) underwent allo-SCT as part of planned primary therapy after achieving their first remission [6 were in complete remission 1 (CR1) and 4 were in partial remission 1 (PR1)], whereas 26 patients (72%) underwent allo-SCT for relapsed/refractory disease. CHOP was administered in 19 patients (53%) as the primary therapy. 17 (47%) patients received alternative chemotherapy regimen due to patient and/or physician preference. The clinical status at the time of transplantation was CR in 12 patients (33%), relapsed sensitive disease n=10 (28%), relapsed untreated n=5 (14%), partial remission (PR) in 5 (14%), primary progressive disease n=3 (8%) and relapsed resistant disease n=1 (3%).Thirty two patients (89%) underwent myeloablative conditioning, 4 (11%) underwent reduced intensity conditioning (RIC). The conditioning regimens included: cyclophosphamide/TBI n=24 (67%), busulfan/cyclophosphamide n=5 (14%), fludarabine containing reduced intensity n=4 (11%), and other regimens n= 3 (8%). With a median follow-up of alive patients from the time of allo-SCT of 69 months (range 1-186 months). At last follow-up, 17 (47%) patients have died, 6 from disease relapse, 5 from graft vs host disease (GVHD), 2 from regimen related toxicity and 4 from other causes. Nineteen patients (53%) still alive at last follow up post-transplant of which 14 (39%) still in remission. The 5-year event free survival (EFS) and overall survival (OS) from the time of allo-SCT of all patients were 43% and 63%, respectively. For PTCL-NOS the 5-year EFS and OS were 52% and 69%, respectively. Table 1 summarizes the patients' characteristics. Figures 1 and 2 shows the Kaplan-Meier curves for OS and EFS respectively.Conclusion:Allo-SCT can be effective strategy in select patients with relapsed/refractory PTCL and those with high risk histologies in the upfront setting PTCL with an acceptable toxicity. [Display omitted] [Display omitted] [Display omitted] DisclosuresToze:Roche Canada: Research Funding. Sehn:roche/genentech: Consultancy, Honoraria; amgen: Consultancy, Honoraria; seattle genetics: Consultancy, Honoraria; abbvie: Consultancy, Honoraria; TG therapeutics: Consultancy, Honoraria; celgene: Consultancy, Honoraria; lundbeck: Consultancy, Honoraria; janssen: Consultancy, Honoraria. Scott:NanoString Technologies: Patents & Royalties: named inventor on a patent for molecular subtyping of DLBCL that has been licensed to NanoString Technologies. Villa:Lundbeck: Honoraria; Roche: Honoraria, Research Funding; Celgene: Honoraria. Connors:NanoString Technologies: Research Funding; F Hoffmann-La Roche: Research Funding; Bristol Myers Squib: Research Funding; Seattle Genetics: Research Funding; Millennium Takeda: Research Funding. Song:Janssen: Honoraria; Otsuka: Honoraria; Celgene: Honoraria, Research Funding.