The Roles of Radiotherapy and Chemotherapy in the Era of Multimodal Treatment for Early-Stage Nasal-Type Extranodal Natural Killer/T-Cell Lymphoma

Treatment Outcomes and Prognostic Factors of Chemotherapy Combined With Radiation Therapy for Patients With Early-Stage Extranodal Natural Killer/T-Cell Lymphoma

Purpose

This study aimed to assess the treatment outcomes, toxicity, and potential prognostic factors in patients with early-stage extranodal natural killer/T-cell lymphoma treated with radiation therapy combined with chemotherapy.

Methods and Materials

One hundred eighteen patients with stage I/II extranodal natural killer/T-cell lymphoma who were treated with radiation therapy combined with chemotherapy were retrospectively analyzed between July 2003 and January 2019. The median dose was 50 Gy (Range, 45-61.2 Gy). The Kaplan-Meier method was used to calculate progression-free survival and overall survival. The patients were scored according to their prognostic indices.

Results

The overall and complete response rates were 93.2% and 82.2%, respectively. At a median follow-up of 43 months, the 5-year overall survival and progression-free survival rates were 73.9% and 68.4%, respectively. Adverse events of grade 3 or higher were observed in 20 patients (16.9%). Patients with primary disease in the Waldeyer's ring had poorer survival (P = .015). Compared with anthracycline-based regimens, non-anthracycline-based regimens significantly improved the 5-year overall survival (76.6% vs 54.8%, P = .027) and progression-free survival (72.4% vs 53.1%, P = .013). After treatment, the 5-year overall survival rate was 78.6% in complete response patients versus 44.9% in noncomplete response patients (P = .003). For patients with low- and intermediate-low-risk according to the nomogram-revised risk index model, the complete response rate was 100%. When primary lesion data were added to the nomogram-revised risk index as the basis for another prognostic index (modified nomogram-revised risk index), the low-risk (0 to 2 risk factors) and high-risk (3 or more risk factors) categories were noted (84.2% vs 62.2%, P = .036).

Conclusions

Patients with early-stage extranodal natural killer/T-cell lymphoma had high response rates and favorable survival rates with radiation therapy and non-anthracycline-based chemotherapy regimens. Patients who achieved complete response had better survival than those who did not. The extranodal natural killer/T-cell lymphoma-specific prognostic models may require further optimization.

Phase 2 Clinical Trial of Simultaneous Boost Intensity Modulated Radiation Therapy With 3 Dose Gradients in Patients With Stage I-II Nasal Type Natural Killer/T-Cell Lymphoma: Long-Term Outcomes of Survival and Quality of Life

PURPOSE

The aim of this study was to investigate the treatment results and long-term quality of life in patients with early-stage extranodal natural killer/T-cell lymphoma who were prospectively treated with simultaneous boost intensity modulated radiation therapy (SIB-IMRT) with 3 dose gradients.

METHODS AND MATERIALS

Sixty patients with stage I-II nasal cavity natural killer/T-cell lymphoma (NKTCL) and Waldeyer's ring NKTCL were enrolled in a single-arm, prospective, phase 2 clinical trial from August 2011 to April 2015. All patients were treated with definitive radiation therapy combined with short-course induction chemotherapy. A newly designed SIB-IMRT scheme was uniformly adopted, with 54.6 Gy for the gross tumor volume (GTV) of the primary tumor and GTV of the positive lymph nodes, 50.7 Gy for the high-risk clinical target volume (CTV), and 45.5 Gy for the low-risk CTV, all delivered in 26 daily fractions. Before SIB-IMRT, L-asparaginase-based induction chemotherapy was used in 95.0% (57/60) of patients.

RESULTS

With a median follow-up time of 95.8 months, the 5-year locoregional recurrence-free survival, progression-free survival, and overall survival rates were 83.3%, 81.7%, and 88.3%, respectively. Dosimetric analysis in the first 21 patients showed satisfying conformality for planning target volume of GTV, high-risk CTV, and low-risk CTV, while the organs at risk were well protected. The results of long-term quality-of-life investigations in patients without progression were favorable, and nasal discomfort was the most common symptom. No grade 3 or 4 acute or late toxicities were observed.

CONCLUSIONS

The scheme of target volume delineation and dose setting that we designed has favorable clinical effects with mild side effects in treating patients with stage I-II nasal cavity NKTCL and Waldeyer's ring NKTCL.

Treatment of extranodal NK/T-cell lymphoma: From past to future

Extranodal NK/T-cell lymphoma (ENKTCL) is the most common subtype of T/NK-cell lymphoma in Asia and Latin America, but very rare in North American and Europe. Patient survival has improved significantly over the past two decades. However, standard treatment has not yet been established, although dozens of prospective trials have been conducted. To help understand how the treatment of ENKTCL has evolved in the past and what trends lie ahead, we have comprehensively reviewed the treatment of this aggressive malignancy, with a particular focus on neglected or unanswered issues, such as the optimal staging method, the best partner of asparaginase (Asp), the individualized administration of Asp, the preferred sequence of CT and RT and so on. Overall, the 5-year overall survival (OS) of patients with Ann Arbor stage I/II disease increased from < 50% in the early 20th century to > 80% in recent years, and the median OS of patients with Ann Arbor stage III/IV disease increased from < 1 year to more than 3 years. The improvement in patient survival is largely attributable to advances in radiation technology and the introduction of Asp and anti-PD-1/PD-L1 immunotherapy into practice. Radiotherapy is essential for patients with early-stage disease, while Asp-based chemotherapy (CT) and PD-1/PD-L1 inhibitors significantly improved the prognosis of patients with advanced-stage disease. ENKTCL management is trending toward simpler regimens, less toxicity, and higher efficacy. Novel drugs, such as manufactured T cells, monoclonal antibodies, and small molecule inhibitors, are being intensively investigated. Based on the fact that ENKTCL is highly resistant to cytotoxic drugs except Asp, and aggressive CT leads to higher toxicity rather than better outcomes, we recommend it is unnecessary to expend additional resources to compare different combinations of Asp with cytotoxic agents. Instead, more efforts should be made to optimize the use of Asp and immunotherapy to maximize efficacy and minimize toxicity, explore ways to overcome resistance to Asp and immunotherapy, identify novel treatment targets, and define subpopulations who may benefit more from specific treatments.

The optimal timing of radiotherapy in the combination treatment of limited-stage extranodal natural killer/T-cell lymphoma, nasal type: an updated meta-analysis

This study was designed to explore the relative efficacy and toxicity of upfront radiotherapy (RT) and late RT in combination treatments for patients with limited-stage extranodal natural killer/T-cell lymphoma nasal type (LS-ENKTL). We searched for clinical trials in the PubMed database that compared upfront RT with late RT in the combined treatment of patients with LS-ENKTL. We systematically evaluated the differences in survival, treatment response, and treatment-related adverse events (AEs) between these two groups. Ten retrospective studies with a total of 1752 patients were included. Upfront RT significantly prolonged the overall survival (OS) and progression-free survival (PFS) of patients compared to late RT in combination with chemotherapy (CT) (HR = 0.72, 95% CI 0.59-0.88, P = 0.001 for OS; HR = 0.57, 95% CI 0.41-0.79, P = 0.0007 for PFS). The complete remission (CR) rate in the upfront RT group was superior to that in the late RT group (HR = 1.61, 95% CI 1.09-2.37, P = 0.02). Patients experienced similar local recurrence-free survival (LRFS), objective response rates (ORR), and toxicity between these two arms (P > 0.05 for all) in the analysis of each subgroup. The survival benefit of upfront RT was not correlated with the RT dose, concurrent chemoradiotherapy (CCRT) (or not), or the CT regimen (P > 0.05 for all). Without compromises in terms of toxicity, RT dose, and treatment modality, upfront RT can significantly benefit OS, PFS, and CR compared to late RT in combination treatment. These findings verified that the upfront RT regimen is more suitable for patients with LS-ENKTL.

The promising outcome with simultaneous integrated boost intensity modulated radiotherapy in confined nasal extranodal NK/T-cell lymphoma

The study aimed to retrospectively analyze the prognosis of patients with stage IE nasal extranodal natural killer/T-cell lymphoma (ENKTL) with dose reduction to clinical target volume (CTV) by using simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT). Forty-four patients were reviewed retrospectively. The prescribed dose was 45 Gy/25 fractions for extended involved-field site and 50-55 Gy/25 fractions for primary tumor site by using SIB-IMRT. The 5-year overall survival (OS), local control (LC) and progression-free survival (PFS) were 81.2%, 93.0%, and 78.8%, respectively. The complete response (CR) rate was 85.4% (37/44). Three patients (6.8%) patients had local failure and 3 (6.8%) patients developed systemic failure. There was only one patient had grade 3 mucositis and 2 patients had grade 3 or grade 4 hematologic toxicities. For patients with stage IE nasal ENKTL, appropriate dose reduction to CTV by SIB-IMRT strategy is feasible and safe with a promising outcome.

Risk-based, response-adapted therapy for early-stage extranodal nasal-type NK/T-cell lymphoma in the modern chemotherapy era: A China Lymphoma Collaborative Group study

We aimed to determine the survival benefits of chemotherapy (CT) added to radiotherapy (RT) in different risk groups of patients with early-stage extranodal nasal-type NK/T-cell lymphoma (ENKTCL), and to investigate the risk of postponing RT based on induction CT responses. A total of 1360 patients who received RT with or without new-regimen CT from 20 institutions were retrospectively reviewed. The patients had received RT alone, RT followed by CT (RT + CT), or CT followed by RT (CT + RT). The patients were stratified into different risk groups using the nomogram-revised risk index (NRI). A comparative study was performed using propensity score-matched (PSM) analysis. Adding new-regimen CT to RT (vs RT alone) significantly improved overall survival (OS, 73.2% vs 60.9%, P < .001) and progression-free survival (PFS, 63.5% vs 54.2%, P < .001) for intermediate-risk/high-risk patients, but not for low-risk patients. For intermediate-risk/high-risk patients, RT + CT and CT + RT resulted in non-significantly different OS (77.7% vs 72.4%; P = .290) and PFS (67.1% vs 63.1%; P = .592). For patients with complete response (CR) after induction CT, initiation of RT within or beyond three cycles of CT resulted in similar OS (78.2% vs 81.7%, P = .915) and PFS (68.2% vs 69.9%, P = .519). For patients without CR, early RT resulted in better PFS (63.4% vs 47.6%, P = .019) than late RT. Risk-based, response-adapted therapy involving early RT combined with CT is a viable, effective strategy for intermediate-risk/high-risk early-stage patients with ENKTCL in the modern treatment era.

Long-term outcomes of upfront concurrent chemoradiotherapy followed by P-GDP regimen in newly diagnosed early stage extranodal nasal-type NK/T cell lymphoma: A prospective single-center phase II study

The optimal treatment strategy of newly diagnosed stage I/II, extranodal nasal-type natural killer/T cell lymphoma (NKTCL) remains unclear. This prospective phase II trial was conducted to explore the short-term and the long-term efficacy and safety of upfront concurrent chemoradiotherapy (CCRT) followed by pegaspargase, gemcitabine, dexamethasone, cisplatin (P-GDP) regimen in patients newly diagnosed with early stage NKTCL.Thirty patients newly diagnosed with stage I/II NKTCL were enrolled from January 2013 to December 2016, and treated as the following strategy: upfront CCRT with cisplatin weekly (25 mg/m) for 5 weeks, followed by 3 cycles of P-GDP regimen chemotherapy (pegaspargase 2500IU/m capped at 3750IU, intramuscular on day 4, gemcitabine 850 mg/m intravenous on days 1 and 8; dexamethasone 40 mg/day intravenous on days 1 to 4; and cisplatin 20 mg/m intravenous on days 1-3) 3 weeks after the completion of CCRT. The objective response rate (ORR) and the complete response (CR) rate were the primary endpoints, and the secondary endpoints were the overall survival (OS), progression-free survival (PFS), and the adverse event (AE).The median follow-up period was 51.5 months (range, 5-78months). The ORR was 93.3% (28/30) and all these 28 patients attained CR at the end of the treatment. Two patients suffered from lymphoma associated hemophagocytic syndrome (LAHS) during the period of consolidation chemotherapy and died within 2 months. The 5-year OS was 93.3%, and the 5-year PFS was 89.4%Mucositis was the most common grades 3/4 nonhematologic AEs (10%, 3/30) of CCRT. During the P-GDP chemotherapy, vomiting (6.7%, 2/30), neutropenia (43.3%, 13/30) and thrombocytopenia (23.3%, 7/30) were the major grades 3/4 toxicities during chemotherapy. No treatment-related deaths occurred.The upfront CCRT followed by P-GDP regimen chemotherapy is an effective and well-tolerated first-line treatment strategy for patients diagnosed with early stage NKTCL. Further investigation of larger sample size is warranted.

Upfront radiation is essential for high-risk early-stage extranodal NK/T-cell lymphoma, nasal type: comparison of two sequential treatment modalities combining radiotherapy and GDP (gemcitabine, dexamethasone, and cisplatin) in the modern era

Early/upfront radiation was associated with improved survivals compared with late radiation for early-stage NK/T-cell lymphoma (NKTCL) in the old era when anthracycline-base chemotherapy (CT) prevailed. However, in the modern era of effective l-asparaginase/gemcitabine-based CT, the optimal timing of radiation is unclear. In this study, 75 patients with newly diagnosed NKTCL, who were treated with combined involved-field intensity-modulated radiotherapy and GDP (gemcitabine, dexamethasone, and cisplatin) were retrospectively reviewed, including 45 from the RT + CT group and 30 from the CT + RT ± CT group. Compared with CT + RT ± CT, RT + CT sequence achieved superior progression-free survival (5-year PFS: 81.6% vs. 56.0%, p = .017) and locoregional control (LRC) (90.8% vs. 66.9%; p = .020). Responses, overall survivals or adverse event incidences did not differ across the groups. Upfront RT was a powerful prognostic variable for favorable PFS (HR 0.302; 95% CI: 0.125-0.729; p = .008). It indicated that upfront RT administration remains vital in enhancing LRC and survival for localized NKTCL in the modern era.

Granulysin, a novel marker for extranodal NK/T cell lymphoma, nasal type

Granulysin is a cytolytic protein expressed in cytotoxic T and natural killer (NK) cells. Abnormal serum levels of granulysin in lymphomas with NK and cytotoxic phenotype have been shown to correlate with tumour progression. In this study, we investigated the expression pattern of granulysin in routine sections of normal and reactive lymphoid tissues as well as in a large series of lymphomas. In normal tissues, granulysin labelled a small population of cells that double immunostaining revealed to belong to the pool of cytotoxic T/NK cells. Among lymphoid neoplasms, the highest expression of granulysin (71%) was found in extranodal NK/T cell lymphomas of nasal type (ENKTL). To note is that 29% of ENKTLs, which were negative for one or more of classical cytotoxic markers strongly expressed granulysin. Furthermore, expression of granulysin was observed in rare cases of T cell lymphomas with a cytotoxic phenotype (i.e. ALK-negative anaplastic large cell lymphoma (26%), enteropathy-associated T cell lymphoma (12%) and peripheral T cell lymphoma, NOS (4%)). None of the investigated non-Hodgkin B cell lymphomas, Hodgkin lymphoma and plasma cell myeloma were granulysin positive. The results suggest granulysin as a novel marker for a subset of cytotoxic NK cell derived malignancies and its usefulness is highlighted in those ENKTLs that lack expression of other cytotoxic markers but retain granulysin expression.

The optimal timing of radiotherapy in the combined modality therapy for limited-stage extranodal NK/T cell lymphoma (ENKTL): a systematic review and meta-analysis

The optimal timing and sequencing of radiotherapy (RT) and chemotherapy (CT) in the treatment of limited-stage extranodal NK/T cell lymphoma (LS-ENKTL) has not been elucidated. The aim of this meta-analysis was to evaluate whether the timing of RT in relation to CT affects the survival of patients with LS-ENKTL. We searched Medline, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, Clinicaltrials.gov , and relevant meeting abstract databases from inception through April 2018 without age or language restrictions. Studies comparing upfront RT plus CT with induction CT followed by RT in patients with LS-ENTKL were eligible for inclusion. Seven studies with 1593 patients were included, and all were retrospective cohort studies. Compared with induction CT followed by RT, upfront RT significantly improved OS of patients with LS-ENTKL (HR = 0.70, 95%CI 0.55-0.88, P = 0.002), with no evidence of heterogeneity across studies (I² = 0%). In subgroup analyses, the beneficial effect of upfront RT on survival did not differ significantly between subgroups of studies with different types of chemotherapy regimens (anthracycline-based or non-anthracycline-based), the administration of concurrent chemoradiotherapy or not, and different median doses of RT (≥ 45 or < 45 Gy). These results suggest that upfront RT plus CT confers survival advantage over induction CT followed by RT for the treatment of LS-ENTKL, and this survival advantage is not significantly affected by the types of CT regimens or timing of CT. Given the retrospective nature of included studies, these results should be interpreted with caution in clinical practice.

A comparison of treatment modalities for nasal extranodal natural killer/T-cell lymphoma in early stages: The efficacy of CHOP regimen based concurrent chemoradiotherapy

This study was designed to evaluate the efficacy of several treatment modalities, including CHOP based concurrent chemoradiotherapy (CCRT), for the patients with stage IE or IIE nasal extranodal NK/T-cell lymphoma (nasal ENKL). The cases were retrieved between 2000 and 2010 (n=94), and were followed to the end of February 2016. The patients were grouped into A (chemotherapy alone; CT alone), B (sequential treatment) and C (CCRT). For those with efficacy evaluation for overall treatment (n=90), CR was attained in 60.0% (18/30), 69.8% (30/43) and 76.5% (13/17) patients in the group A, B and C, respectively. The 5-year OS rate was 35.2%, 41.9% and 70.6% in the group A, B and C, respectively. For patients with early stage diseases (IE and IIE), the ECOG performance status and the Ann Arbor stage were significant prognostic factors for both OS and PFS. Among the stage IE patients, besides the ECOG performance status, three prognostic factors which related to treatments (treatment modalities, efficacy of initial and overall treatment) were significant against OS or PFS. In conclusion, compared to chemotherapy alone and sequential treatment, nasal ENKL patients in early stages, especially stage IE, benefit the most from CHOP based concurrent chemoradiotherapy.

Hemoglobin level, a prognostic factor for nasal extranodal natural killer/T-cell lymphoma patients from stage I to IV: A validated prognostic nomogram

Although nasal extranodal natural killer/T-cell lymphoma (nasal ENKL) shares some prognostic factors with other lymphomas, seldom studies had explored the prognostic value of hemoglobin. The ENKL cases in stage I–IV during 2000 to 2015 were collected from two medical centers (group A, n = 192), and were randomly divided into the group B (n = 155) and C (n = 37). Although the significant factors identified by the univariate analysis differed between the group A and B, the multivariate Cox regression indicated the same factors. C-index of the model was slightly better than Yang’s, but its integrated Brier score (IBS) was obviously lower than Yang’s both in the group A and B. Additionally, minimal depth of random survival forest (RSF) classifier confirmed that the prognostic ability of hemoglobin was better than age both in the group A and B. In the calibration of the nomogram, the predicted 3-year or 5-year OS of our nomogram well agreed with the corresponding actual OS. In conclusion, Hemoglobin is a prognostic factor for nasal ENKL patients in stage I - IV, and integrating it into a validated prognostic nomogram, whose generalization error is the smallest among the evaluated models, can be used to predict the patients’ outcome.