Epidemiology, Clinical Features, and Outcome of HTLV-1-Related Adult T-Cell Leukemia/Lymphoma in Latin America: A Study from the Latin American Group of Lymphoproliferative Disorders (GELL)

INTRODUCTION: Adult T-cell leukemia/lymphoma (ATLL) is a mature peripheral T-cell neoplasm caused by the Human T-cell Leukemia Virus Type 1 (HTLV-1). HTLV-1 infects up to 10 million people worldwide and is most endemic in Southwestern Japan, the Caribbean basin, South America, and Western Africa. In Latin America (LA), Peru and Brazil have the highest prevalence of HTLV-1-related diseases, however, data on ATLL in other LA countries is scarce. ATLL carries a dismal prognosis and is essentially incurable by conventional drugs. We describe the epidemiology, clinical features, treatment, and disease outcome of ATLL encountered in 11 countries in LA. METHODS: We retrospectively analyzed patients (pts) diagnosed with ATLL between January 1995 and December 2019. ATLL cases were classified according to the Shimoyama criteria into acute (A), lymphomatous (L), chronic (C) and smoldering (S). Treatment approaches used as first-line therapy were: 1) chemotherapy alone; 2) combined chemotherapy with zidovudine/interferon-alpha (AZT-IFN); and 3) AZT-IFN alone, as previously done with Miami cohort (Malpica and Ramos et al. Blood Advances 2018). Treatment response was assessed according to Tsukasaki et al. (JCO 2009) criteria. To be classified as complete response (CR), partial response and stable disease, these had to persist for a period of at least 4 weeks. Survival curves were estimated using the Kaplan-Meier method and Log rank test. RESULTS: A total of 253 pts with ATLL were identified. Two hundred twenty six pts (L=122, A=73, C=26, S=5) had sufficient data for analysis. Demographic and clinical features are shown in Figure 1 and Table 1. Median age at diagnosis was 57 years, with a female predominance in A (58%) and S (100%) types. Most ATLL pts were from Peru (n=159, 63%) followed by Chile (n=44, 17%), Argentina (n=20, 8%) and Colombia (n=17, 7%). B symptoms were high present in A, L and C types (73%, 72%, 58% vs. 8% S type, respectively, p=0.011). Hypercalcemia was highly associated with A type (57% vs. L 27%, p=0.014). The PIT score yielded to a more aggressive risk classification compared to the IPI score (high-risk: 55% vs. 29%, respectively, p<0.001). Strongyloidiasis (n=5) and pneumocystis jirovecii pneumonia (n=5) were the most commonly observed co-infections at diagnosis. Commonly affected extranodal sites other than bone marrow in all subtypes were skin 25% (n=63) and liver 9% (n=24). The therapy approach used during the first 2 therapy evaluations are summarized in Table 2. The median survival (MS) times were 4.3 months, 7.9 months, 21.1 months, and not reached for A, L, C and S form, with 4-year survival of 8%, 22%, 40% and 80%, respectively (Figure 2). First-line AZT-IFN resulted in overall response (OR) rate of 63% (CR 24%) for A (n=8) and 75% (CR 50%) for L (n=8), respectively (Table 3). The OR rates after first-line multi-agent chemotherapy alone for A vs. L were 21% (CR 8%) and 41% (CR 29%), respectively (Table 3). The most commonly used regimens were CHOP/CHOP-like (n=117, 59%) and CHOEP (n=40, 20%) regimens with OR rates of 29% (CR 12%) and 60% (CR 42%), respectively (Table 3). Progression-free survival (PFS) rates in pts with aggressive ATLL who achieved CR after chemotherapy vs. AZT-IFN (alone or in combination with chemotherapy) were 2.8 months vs. 30.4 months for A (n=8) type and 67.1 months vs. 17.7 months for L (n=30) type, respectively (Figure 3). Only 2 pts with L type underwent allogeneic hematopoietic stem cell transplant (allo-HSCT) with PFS of 12 and 17 months (Table 4). CONCLUSION: ATLL continues to carry a dismal outcome with conventional therapies thus urging the development of novel approaches. Our study found that Latin American ATLL variant presents at a younger age, has a female predominance, high incidence of L type, low incidence of indolent types and lower survival rates, suggesting that Latin American ATLL variant presents earlier and more aggressively than in Japanese pts. AZT-IFN produced durable responses in A type patients who achieved CR as compared to chemotherapy alone. Chemotherapy responses were more durable in L types who achieved CR as compared to A type. In conclusion, in the management of aggressive ATLL, chemotherapy remains the preferred choice for L type (with consideration of allo-HSCT upfront), while AZT-IFN is a good option to attempt for A type upfront. Figure Disclosures Peña: Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sandoz: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees; Amgen: Speakers Bureau; BindingSite: Research Funding. Idrobo:Amgen: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Tecnofarma: Honoraria, Speakers Bureau; Takeda: Honoraria, Speakers Bureau; Abbvie: Honoraria, Speakers Bureau. Altamirano:Hospital Nacional Guillermo Almenara Irigoyen: Other: Servicio de Hematologia. Perini:Abbvie: Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Takeda: Honoraria. Castillo:Janssen: Consultancy, Research Funding; Abbvie: Research Funding; TG Therapeutics: Research Funding; Kymera: Consultancy; Pharmacyclics: Consultancy, Research Funding; Beigene: Consultancy, Research Funding. Ramos:NIH: Research Funding. Villela:Roche: Other: advisory board, Speakers Bureau; amgen: Speakers Bureau

Impact of Cutaneous Involvement on the Clinical Outcome of Adult T-Cell Leukemia/Lymphoma: A Study from the Latin American Group of Lymphoproliferative Disorders (GELL)

INTRODUCTION: Adult T-cell leukemia/lymphoma (ATLL) is an aggressive peripheral T-cell neoplasm caused by the Human T-cell Leukemia Virus Type 1 (HTLV-1). HTLV-1 infects up to 10 million people worldwide and is most endemic in Southwestern Japan, Western Africa, the Caribbean basin and South America. Cutaneous signs of ATLL are varied and may consist of macules (M), plaques (P), multiple papules (MP), tumoral nodules (TN), erythroderma (E) or mixed-lesions (≥2 predominant lesions, ML). M and P forms are believed to carry a better prognosis. However, data on cutaneous presentation of ATLL remains scarce. Herein, we report cases of ATLL with cutaneous involvement diagnosed in 4 Latin American countries over the last 3 decades. METHODS: We retrospectively analyzed patients (pts) diagnosed with ATLL between January 1995 and December 2019. ATLL subtypes were classified according to the Shimoyama criteria into acute, lymphomatous, chronic and smoldering. Primary cutaneous tumoral (PCT) variant was classified according to the 2019 International Revised ATLL Consensus. We designed 2 cohorts: the first, ATLL pts with cutaneous involvement, and the second, matched cases without cutaneous involvement. We determined the type of skin lesion as well as the survival associated with the various types of skin lesions. We compared the frequency of clinical features using Fisher's exact test. Treatment response was assessed according to Tsukasaki et al. (JCO 2009) criteria. To be classified as complete response (CR), partial response, and stable disease, these had to persist for a period of at least 4 weeks. We analyzed survival data according to ATLL subtype, cutaneous involvement status, and type of skin lesion using the Kaplan-Meier method and Log rank test. RESULTS: A total of 169 pts with ATLL were identified; 63 had cutaneous involvement and 106 did not. Clinical features are shown in Table 1. In both groups the median age was 57 years with a female predominance. Cutaneous involvement was most frequently found in acute (41%) and lymphomatous (37%) ATLL pts. The E (24%) and P (22 %) types were the most frequent skin lesions. Disease stage, presence of B symptoms, hypercalcemia, ECOG ≥2, elevated LDH, and IPI/ PIT score were not different among groups. Table 2 and Table 3 summarize the first-line therapy used and response rates. The use of first-line zidovudine plus interferon alpha (AZT-IFN), regardless of the type of skin lesion, resulted in relatively high response rates [overall response (OR) 100%, n=8; CR 62.5%] as compared to multi agent-chemotherapy (OR 33.3%, n=12). Overall, the presence of cutaneous involvement was associated with better overall survival (OS) compared to non-cutaneous involvement (aHR 0.55 [95% CI: 0.37-0.82], p<0.01; 1-year OS 53% vs. 27%, respectively, p=0.012) (Figure 1). PCT pts had better outcome compared to acute and lymphomatous ATLL forms (1-year OS 75% vs. 39% vs. 25%, respectively, p=0.002). The presence of P and MP skin lesions was associated with better OS compared to other subtypes (1-year OS: P/MP 65% vs. others 41%, respectively, p=0.027) (Figure 2, supplemental figure 1). In a multivariate analysis, hypercalcemia was an independent poor prognostic factor for survival among ATLL pts with cutaneous involvement (aHR 3.99 [95% CI: 139-11.45], p=0.01) (supplemental figure 2). One patient with lymphomatous ATLL and plaque lesions underwent allogeneic stem cell transplant with high-dose chemotherapy after achieving CR with AZT-IFN; patient remains alive and progression-free for 17 months. Illustrative cases of cutaneous ATLL are shown in Figure 3. CONCLUSION: In Latin American pts with aggressive ATLL, cutaneous involvement appears to be associated with better survival compared to non-cutaneous involvement. PCT subtype, an ATLL variant characterized by isolated skin lesions with no organ involvement and poor outcome, appeared to have a better prognosis compared to acute and lymphomatous ATLL forms. P and MP skin lesions were both associated with better survival. Hypercalcemia was found as an independent prognostic factor for survival in pts with cutaneous involvement. Finally, AZT-IFN appears to be reasonable first-line option for aggressive ATLL subtypes with cutaneous involvement regardless of the type of skin lesion at diagnosis, based on the relatively high response rates observed in this subset; further investigation in randomized clinical trials is needed. Disclosures Peña: Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sandoz: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees; Amgen: Speakers Bureau; BindingSite: Research Funding. Idrobo:Takeda: Honoraria, Speakers Bureau; Tecnofarma: Honoraria, Speakers Bureau; Abbvie: Honoraria, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Amgen: Honoraria, Speakers Bureau. Altamirano:Hospital Nacional Guillermo Almenara Irigoyen: Other: Servicio de Hematologia. Perini:Abbvie: Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Takeda: Honoraria. Castillo:Pharmacyclics: Consultancy, Research Funding; Beigene: Consultancy, Research Funding; Abbvie: Research Funding; Kymera: Consultancy; TG Therapeutics: Research Funding; Janssen: Consultancy, Research Funding. Ramos:NIH: Research Funding. Villela:amgen: Speakers Bureau; Roche: Other: advisory board, Speakers Bureau