Advances in follicular lymphoma

Efficacy and toxicity of two schedules of bortezomib in patients with recurrent or refractory follicular lymphoma: a randomised phase II trial from the Groupe d'Etude des Lymphomes de l'Adulte (GELA)

PURPOSE

Bortezomib has previously demonstrated activity in indolent lymphomas including follicular lymphoma with response rate ranging from 13% to 56%. However, the optimal schedule of bortezomib remains to be investigated in follicular lymphoma.

EXPERIMENTAL DESIGN

We conducted a randomised phase II study where patients with follicular lymphoma in relapse or refractory receive either bortezomib 1.5 mg/m(2) biweekly on days 1, 4, 8 and 11 of a 21-day cycle (arm A) or 1.6 mg/m(2) weekly on days 1, 8, 15 and 22 of a 35-day cycle (arm B). An interim analysis was planned after 15 fully evaluable patients randomised in each treatment arm. If only five subjects or fewer respond, the treatment arm was concluded to be ineffective and was closed to inclusion.

RESULTS

Eighty-seven patients were included in the trial. Arm B was closed to inclusion after interim analysis. 15/50 patients (30%) in arm A and 8/37 patients (22%) in arm B achieved a response. Median duration of response was 16 and 15 months for arms A and B, respectively. Most drug-related adverse events (AEs) (all grades, all cycles) were mild.

CONCLUSION

This study demonstrates tolerability and durable clinical benefit of bortezomib when given at 1.5 mg/m(2) biweekly. Despite a higher response rate in the biweekly arm, no major difference in patient's outcome was observed between the two arms in the final analysis.

Antiproliferative Properties of Type I and Type II Interferon

The clinical possibilities of interferon (IFN) became apparent with early studies demonstrating that it was capable of inhibiting tumor cells in culture and in vivo using animal models. IFN gained the distinction of being the first recombinant cytokine to be licensed in the USA for the treatment of a malignancy in 1986, with the approval of IFN-α2a (Hoffman-La Roche) and IFN-α2b (Schering-Plough) for the treatment of Hairy Cell Leukemia. In addition to this application, other approved antitumor applications for IFN-α2a are AIDS-related Kaposi's Sarcoma and Chronic Myelogenous Leukemia (CML) and other approved antitumor applications for IFN-α2b are Malignant Melanoma, Follicular Lymphoma, and AIDS-related Kapoisi's Sarcoma. In the ensuing years, a considerable number of studies have been conducted to establish the mechanisms of the induction and action of IFN's anti-tumor activity. These include identifying the role of Interferon Regulatory Factor 9 (IRF9) as a key factor in eliciting the antiproliferative effects of IFN-α as well as identifying genes induced by IFN that are involved in recognition of tumor cells. Recent studies also show that IFN-activated human monocytes can be used to achieve >95% eradication of select tumor cells. The signaling pathways by which IFN induces apoptosis can vary. IFN treatment induces the tumor suppressor gene p53, which plays a role in apoptosis for some tumors, but it is not essential for the apoptotic response. IFN-α also activates phosphatidylinositol 3-kinase (PI3K), which is associated with cell survival. Downstream of PI3K is the mammalian target of rapamycin (mTOR) which, in conjunction with PI3K, may act in signaling induced by growth factors after IFN treatment. This paper will explore the mechanisms by which IFN acts to elicit its antiproliferative effects and more closely examine the clinical applications for the anti-tumor potential of IFN.

Multicenter Randomized Phase II Study of Weekly or Twice-Weekly Bortezomib Plus Rituximab in Patients With Relapsed or Refractory Follicular or Marginal-Zone B-Cell Lymphoma

Purpose

To determine overall response rate (ORR), time to progression (TTP), and duration of response (DOR) with twice-weekly/weekly bortezomib plus rituximab, and evaluate safety/tolerability, in patients with relapsed or refractory CD20+ follicular lymphoma (FL) or marginal-zone lymphoma.

Patients and Methods

Patients were randomly assigned (minimization method) to bortezomib 1.3 mg/m2 twice weekly (days 1, 4, 8, and 11; 21-day cycle, five cycles; arm A) or bortezomib 1.6 mg/m2 weekly (days 1, 8, 15, and 22; 35-day cycle, three cycles; arm B) plus rituximab 375 mg/m2 weekly for 4 weeks (both arms). Response/progression was determined by International Workshop Response Criteria using oncologist/radiologist-adjudicated data from independent radiology review and investigator assessment.

Results

Eighty-one patients (arm A, n = 41; arm B, n = 40) were enrolled. Dose-intensity was higher in arm A; mean total bortezomib received was similar between arms (18.5 and 17.1 mg/m2). In arm A, ORR was 49% (14% complete response [CR]/CR unconfirmed [CRu]), median TTP was 7.0 months, and median DOR was not reached. In arm B, ORR was 43% (10% CR/CRu), and median TTP/DOR were 10.0/9.3 months. The weekly combination regimen seemed better tolerated. Grade 3 or worse adverse events seemed more common in arm A (54%) versus arm B (35%), including thrombocytopenia (10% v 0%) and peripheral neuropathy (10% v 5%), but diarrhea seemed less frequent (7% v 15%). No grade 4 toxicities were reported in arm B.

Conclusion

Both bortezomib plus rituximab regimens seem feasible in relapsed or refractory indolent lymphomas. The more convenient weekly combination regimen is being compared with single-agent rituximab in an ongoing phase III study in relapsed FL.

Characterization of follicular lymphoma in the small intestine using double-balloon endoscopy

Follicular lymphomas occur rarely in the gastrointestinal tract, representing only 1-3% of all gastrointestinal tract B-cell non-Hodgkin lymphomas. We describe endoscopic analysis of 3 cases of follicular lymphoma in the small intestine using double-balloon endoscopy. Double-balloon endoscopy revealed multiple nodular lesions and elevated white patches, multiple polypoid lesions, and scattered white polypoid and nodular lesions in the duodenum and small intestine. Fuji Intelligent Chromo Endoscopy demonstrated small, whitish nodules, and narrow-band imaging showed a coiled, elongated vascular pattern within the elevated lesions. These cases are the first follicular lymphomas in the small intestine evaluated using narrow-band imaging or Fuji Intelligent Chromo Endoscopy to be reported.

Economic evaluation of rituximab plus cyclophosphamide, vincristine and prednisolone for advanced follicular lymphoma

The addition of rituximab to cyclophosphamide, vincristine and prednisolone (CVP) for advanced follicular lymphoma increases median time to progression by 17 months. A US societal cost-effectiveness of R-CVP versus CVP is estimated for a representative 50-year-old patient. Progression-free survival (PFS) and overall survival are based on a randomized Phase III trial. Costs are estimated using Medicare reimbursement rates and published drug price data, and include drug and administration costs, adverse events, treatment of relapses, and end-of-life care. Utility estimates are derived from the literature and a 3% discount rate is employed. Mean overall survival is projected to be 1.51 years longer for patients assigned to R-CVP versus CVP. The cost per quality-adjusted year of life gained is $28,565. The utility associated with stable or progressive disease and the unit drug cost of rituximab most influence the findings. The cost-effectiveness ratio of R-CVP compared with CVP is projected to be cost-effective in the United States under a range of sensitivity analyses.

Proteasome inhibition with bortezomib: a new therapeutic strategy for non-Hodgkin's lymphoma

The incidence of non-Hodgkin's lymphoma (NHL) has markedly increased in the US and other westernized countries in recent years and presents a considerable clinical challenge. NHL is divided into subtypes that follow an aggressive or indolent course. Follicular lymphoma (FL), the most common indolent subtype, and mantle cell lymphoma (MCL), an aggressive subtype that accounts for approximately 5% of cases, are generally incurable. MCL has a relatively poor prognosis, with a median survival of 3-4 years. Despite improving response rates with new agents and regimens, the lack of demonstrated improvement in overall survival in many subtypes supports the development of novel approaches, such as proteasome inhibition. Bortezomib is the first proteasome inhibitor to be evaluated in human studies. It has already been approved as second-line treatment in multiple myeloma and is now under active investigation in NHL. The US FDA has granted bortezomib fast-track designation for relapsed and refractory MCL. In vitro and in vivo studies have demonstrated single-agent activity against various lymphoid tumors, and additive or synergistic effects in combination with other agents, including standard chemotherapy drugs employed in NHL. Phase 2 clinical trials indicate that bortezomib is well tolerated and active in several NHL subtypes, with response rates of 18-60% in FL and 39-56% in MCL. A number of combination trials are currently underway with a range of standard agents. Bortezomib has the potential to play a significant role throughout the NHL treatment algorithm in the future.

A primary follicular lymphoma of the duodenum treated successfully with radiation therapy

A 48-year-old man was admitted to our hospital because of repeated episodes of epigastralgia. Endoscopy showed multiple whitish granules extending from the 2nd to 3rd portion of the duodenum. Biopsy specimens showed well circumscribed follicles with a monotonous population of predominantly small cleaved cells that were positive for CD20, CD10 and BCL2, but negative for CD5. A full staging study showed no abnormalities. The tumor was finally diagnosed according to the WHO classification as a stage I follicular lymphoma (FL), grade 1, of the duodenum and subsequently received irradiation to the involved area. After 3 years of followup, he is still in complete remission. Because FL arising in the duodenum has recently reported with increasing frequency, patients with multiple granules in the duodenum should be examined carefully.

What sense lies in antisense inhibition of inducible nitric oxide synthase expression?

The impact of nitric oxide (NO) synthesized after activation by proinflammatory cytokines and/or bacterial products by an inducible NO synthase (iNOS) is still contradictory. Expression of iNOS in inflammatory reactions is often found predominantly in cells of epithelial origin, and in these cases NO may serve as a protective agent limiting pathogen spreading, downregulating local inflammatory reactions by inducing production of Th2-like responses in a classical feedback circle, or limiting tissue damage during stress conditions. However, an abundant amount of data on chronic human disorders with predominant proinflammatory Th1-like reactions points to a destructive role of iNOS activity calling for a specific inhibition. Various methods to inhibit iNOS have been established to elucidate a protective versus a destructive role of NO during various stresses. In this review, we focus on antisense (AS)-mediated gene knock-down as a relatively new method to inhibit NO production and summarize the techniques applied and their successes. At least in theory, it provides a specific, rapid, and potentially high-throughput method for inhibiting gene expression and function. We here discuss the opportunities of iNOS-directed AS-ODN, and extensively deal with limitations and experimental problems.

Chromosomal aberrations in follicular non-Hodgkin lymphomas of Japanese patients, detected with comparative genomic hybridization and polymerase chain reaction analysis

The t(14;18)(q32.3;q21), hallmark of follicular lymphoma (FL), is less frequently observed in Asian patients than in Westerners. Little is known about additional chromosomal aberrations in Asian FL patients. We applied comparative genomic hybridization (CGH) to screen for genomic imbalances in 32 biopsy samples from 23 Japanese patients with nodal FL. The t(14;18) was assessed with polymerase chain reaction (PCR) using primers for the major (MBR), 3'MBR, minor (mcr), 5'mcr, and intermediate breakpoint cluster regions (icr). In 17 of 23 patients, CGH analyses detected genomic imbalances. Gains frequently affected chromosomes 18p (6 of 23), X (5 of 23), 5 (4 of 23), 12 (4 of 23), 2 (3 of 23), and 16 (3 of 23). The only recurrent loss affected chromosome 6q (2 of 23). A t(14;18) was detected in 13 of 23 patients (56.5%). Breakpoints were located in the MBR (10 patients), in the 3'MBR, in the mcr, and in the icr (1 patient each). The frequency of aberrations detected by CGH as well as relapse-free survival were not distinctly different between patients with and without a t(14;18). In summary, no significant difference in the overall frequency of aberrations compared with Westerners was found. Despite the extended primer set used, the frequency of PCR-detected t(14;18) remained low. Additional studies are required to assess the reasons for geographic variation in FL.

Infections associated with purine analogs and monoclonal antibodies

Nucleoside analogs and monoclonal antibodies are commonly used to treat lymphoproliferative disorders and have become established as the treatment of choice in chronic lymphocytic leukemia, hairy cell leukemia, and follicular lymphomas, as well as a number of other malignant lymphoid neoplasms. When used in standard doses, these agents have a low incidence of extramedullary side effects resulting in their inclusion in a number of combination regimens. The most important complications associated with these drugs are myelosuppression, immunosuppression and infections. This is further accentuated when they are used in combination with other drugs such as alkylating agents. Several investigators have attempted to delineate the risk factors predicting the risk of infections associated with these agents. Furthermore, risk-based strategies to decrease the incidence of these infectious complications have been proposed.

Tumor dormancy and MYC inactivation: pushing cancer to the brink of normalcy

Upon MYC inactivation, tumors variously undergo proliferative arrest, cellular differentiation, and apoptosis and in some cases, apparently permanently revoking tumorigenesis. In liver tumor cells, we recently showed that MYC inactivation uncovers stem cell properties and triggers differentiation, but in this case, their neoplastic properties are restorable by MYC reactivation. Thus, whereas oncogene inactivation can push cancer to the brink of normalcy, some cells retain the latent capacity to turn cancerous again, arguing that they may exist in a state of tumor dormancy.

Molecular epidemiology of follicular lymphoma in Chinese: relationship with bcl-2/IgH translocation and bcl-6 397G/C polymorphism

The relative incidence of follicular lymphoma (FL) compared with diffuse large B-cell lymphoma (DLCL) is low in Chinese. This may be due to a lower incidence of t(14;18)-mediated disease, a rapid transformation of FL to DLCL, or a lower incidence of FL-prone genetic polymorphisms (e.g., bcl-6 G397C). Using a conventional and long-distance polymerase chain reaction technique, we showed that 93% (43/46) of Chinese FL cases are t(14;18) related and are molecularly indistinguishable from Caucasian cases. The translocation was uncommonly found in Chinese DLCL cases (8/58, 14%). Furthermore, the incidence of bcl-6 hypermutation in FL and DLCL cases appeared to be comparable. These data do not suggest a high incidence of transformation from FL to DLCL in Chinese. Sequencing study also did not show an increased incidence of G397C polymorphism (heterozygote+homozygotes) in FL compared to a population with Chinese background or DLCL cases (25+5% vs 30+4% vs 22+3%). The reasons for the lower incidence of FL in Chinese remain unanswered.