Bendamustine, Carboplatin and Dexamethasone (BCD) for Refractory or Relapsed Peripheral T-cell Lymphoma

BCD (Bendamustine, carboplatin and dexamethasone)chemotherapy regimen is proposed as the salvage treatment for relapsed or refractory PTCLs in this study protocol, which would be expected to show more promising clinical outcomes than that of bendamustine single therapy. Platinum combination with bendamustine is a theoretically ideal salvage regimen for the patients of PTCLs because these both agents are highly effective drugs in lymphoma treatment and have rare cross-resistance. Carboplatin was selected as a platinum agent for combination with bendamustine, which is a second generation platinum agent and has a less neurotoxicity than that of cisplatin, considering use for previously treated patients with vinc alkaloid agents.

In a prior phase I study of carboplatin in combination with bendamustine for previously untreated small cell lung cancer patients, the recommended dose for phase II studies was bendamustine 100 mg/m2 on day 1 and 2, carboplatin AUC 5 on day 1, respectively \[16\]. In consideration of previously treated subjects, however, the dose of bendamustine was decided on 80mg/m2 in this study protocol with concerning about the toxicities, especially to severe cytopenia.

Dexamethasone is one of the corticosteroids using a key drug for lymphoid malignancy and has a strong antiemetic effect. Therefore, dexamethasone could enhance the therapeutic efficacy and antiemetic effect, using with bendamustine and carboplatin.

Peripheral T-cell lymphoma (PTCL) represents a heterogeneous group of nodal and extranodal mature T-cell lymphomas, which constitute about 5 - 10% of all non-Hodgkin lymphomas (NHLs) in Western countries compared to 20 - 30% of all lymphomas in the East Asia. The most common histologies include PTCL, not otherwise specified (PTCL-NOS), angioimmunoblastic T-cell lymphoma (AITL), and anaplastic large cell lymphoma (ALCL) \[3\]. Most of these subtypes include a high percentage of patients with advanced disease stage, widespread dissemination and aggressive behavior. As a result, the prognosis of PTCL remains dismal, with the 5-year overall survival (OS) rate for many of these subtypes ranging between 25 and 45%, except for ALCL (ALK ), which demonstrates a better 5-year OS (70%) \[4 - 6\]. Thus, new therapeutic strategies are needed to improve the survival of patients with PTCL.

Current multiagent chemotherapeutic regimens for patients with PTCL are extrapolated mainly from therapeutic paradigms of B-cell lymphomas, with the cornerstone treatment being an anthracycline-containing regimen. Although some patients with PTCL can be cured with these approaches, relapsed and chemorefractory disease constitutes a significant clinical dilemma in the care of these patients \[7\]. At present, high dose chemotherapy with autologous stem cell support seems to offer potential curative treatment for those patients with relapsed PTCL who are responsive to salvage chemotherapy \[8\]. However, the majority of elderly patients with relapsed or refractory PTCL cannot benefit from high dose chemotherapy as a result of advanced age, significant comorbidities, poor functional status, toxicities from previous treatments and inherent chemoresistance \[9\]. Conventional salvage regimens have been mostly designed for younger or fitter populations, and can hardly be delivered to these elderly patients due to marked hematologic and non-hematologic toxicities, mainly involving renal and neurological functions \[10\]. Therefore, it is imperative that innovative salvage regimens based on drug combinations with increased efficacy and reduced toxicity be explored for the management of elderly patients with relapsed or refractory PTCLs.

BCD chemotherapy regimen is proposed as the salvage treatment for relapsed or refractory PTCLs in this study protocol, which would be expected to show more promising clinical outcomes than that of bendamustine single therapy. Platinum combination with bendamustine is a theoretically ideal salvage regimen for the patients of PTCLs because these both agents are highly effective drugs in lymphoma treatment and have rare cross-resistance. Carboplatin was selected as a platinum agent for combination with bendamustine, which is a second generation platinum agent and has a less neurotoxicity than that of cisplatin, considering use for previously treated patients with vinc alkaloid agents.

Eligibility Criteria:
Inclusion Criteria:

1. Histologically proven aggressive T-cell Non-Hodgkin's lymphoma (NHL)
2. Age 18 -75 years
3. Ann Arbor stage II, III and IV (Appendix A)
4. Relapsed or refractory cases to previous treatments
5. Performance status (ECOG) ≤ 2 (Appendix B)
6. At least one or more bidimensionally measurable lesion(s)

   * ≥ 2 cm by conventional CT
   * ≥ 1 cm by spiral CT
   * skin lesion (photographs should be taken) ≥ 2 cm
   * measurable lesion by physical examination ≥ 2 cm
7. Cardiac ejection fraction ≥ 50 % as measured by MUGA or 2DECHO without clinically significant abnormalities
8. Adequate renal function: serum creatinine level \< 2 mg/dL (177 μmol/L)
9. Adequate liver functions: Transaminase (AST/ALT) \< 3 X upper normal value (or \< 5 x ULN in the presence of DLBCL involvement of the liver), Bilirubin \< 2 X upper normal value (or \< 5 x ULN in the presence of PTCL involvement of the liver)
10. Adequate BM functions: hemoglobin ≥ 9 g/dL absolute neutrophil count (ANC) ≥ 1,500/μL and platelet count ≥ 75,000/μL, unless abnormalities are due to bone marrow involvement by lymphoma
11. A negative serum or urine pregnancy test prior to treatment must be available both for pre-menopausal women and for women who are \< 1years after the onset of menopause.
12. Informed consent

Exclusion Criteria:

1. ALK-positive anaplastic large cell lymphoma and Sezary syndrome.
2. CNS or testis involvement.
3. Previously treated with the regimen containing bendamustine or platinum agents.
4. Any other malignancies within the past 5 years except curatively treated non-melanoma skin cancer or in situ carcinoma of cervix uteri
5. Pregnant or lactating women, women of childbearing potential not employing adequate contraception
6. Other serious illness or medical conditions
7. Unstable cardiac disease despite treatment, myocardial infarction within 6 months prior to study entry
8. History of significant neurologic or psychiatric disorders including dementia or seizures
9. Active uncontrolled infection (viral, bacterial or fungal infection)
10. Other serious medical illnesses
11. Known hypersensitivity to any of the study drugs or its ingredients
12. Concomitant administration of any other experimental drug under investigation, or concomitant chemotherapy, hormonal therapy, or immunotherapy.