Very good partial response in a patient with MALT-lymphoma of the lung after treatment with low-dose thalidomide

t(11;18)(q21;q21) translocation as predictive marker for non-responsiveness to salvage thalidomide therapy in patients with marginal zone B-cell lymphoma with gastric involvement

PURPOSE

Activation of TNF-α/NF-κB-related signaling pathway is crucial in sustain the growth of Helicobacter pylori-independent gastric mucosa-associated lymphoid tissue type (MALT) lymphoma. Thalidomide is an anti-angiogenic agent with anti-TNF-α and anti-NF-κB activity. This retrospective study evaluated the efficacy of thalidomide in standard therapy-failure gastric MALT lymphoma.

METHODS

Between October 2003 and September 2007, 10 patients with antibiotics-resistant, chemotherapy-refractory gastric MALT lymphoma who received salvage thalidomide therapy at daily doses of 100-200 mg were identified from medical records and included. Status of t(11;18)(q21;q21) was determined by reverse transcriptase polymerase chain reaction for API2-MALT1 transcript, while expression of NF-κB was detected by immunohistochemistry. Tumor response was evaluated by RECIST criteria.

RESULTS

Tumors were of stage IV in seven and IE/IIE-1 in three. The best tumor response after thalidomide was complete response in two and partial in three, with an overall response rate of 50% (95% confidence interval, 12.3-87.7%). At median follow-up of 39.3 months, the 3-year event-free and overall survival rates were 36.0% and 85.7%, respectively. API2-MALT1 transcript was detected in four (40%) tumors. Objective response rates of tumors with and without t(11;18)(q21;q21) were 0% (0/4) and 83% (5/6), respectively, P = 0.048 (Fisher's exact test). Thalidomide treatment was associated with significant down-regulation of nuclear NF-κB expression levels in residual neoplastic cells and microenvironments of responsive tumors, but not in t(11;18)(q21;q21)-positive, thalidomide-refractory tumors.

CONCLUSIONS

Thalidomide is an effective salvage treatment for standard therapy-failure, t(11;18)(q21;q21) translocation-negative gastric MALT lymphoma and deserves further exploration.

Bronchus-associated lymphoid tissue lymphomas: an update of a rare extranodal maltoma

Mucosa-associated lymphoid tissue (MALT) lymphomas were first described by Isaacson and Wright in 1983 in a small series of patients with low-grade B-cell gastrointestinal lymphomas. Although MALT lymphomas occur most frequently in the stomach, they have also been described in various non-gastrointestinal sites, such as the salivary gland, conjunctiva, thyroid, orbit, lung, breast, kidney, skin, liver, uterus, and prostate. The risk of a diagnostic dilemma is reduced by the favorable prognosis of this low-grade lymphoma and its tendency to remain localized to the primary site for a long time. On therapeutic grounds, in contrast to nodal lymphomas, low-grade MALT lymphomas also respond favorably to local treatments, such as surgery and/or local radiation therapy. The outcome and prognosis of low-grade MALT lymphomas are more favorable than those for other extranodal lymphomas. The purpose of this review is to point out the state of the art regarding bronchus-associated lymphoid tissues lymphomas in terms of etiology, pathogenesis, clinics, and therapeutics, including our single-center experience of 23 cases.

Targeted therapies for non-Hodgkin lymphoma: rationally designed combinations

Non-Hodgkin lymphoma is a diverse group of lymphoid malignancies treated historically with cytotoxic chemotherapy. Recent technologic advances have enabled the development of new therapies specifically targeted to inhibit various pathways involved in disease pathophysiology. Led by the anti-CD20 monoclonal antibody rituximab, these agents are expected to revolutionize patient care. Several new drugs might have limited single-agent activity but could combine with other targeted therapies to produce significant effects. Although the current level of understanding makes this sort of rational combination challenging, there is evidence that certain combinations might be very effective. Examples include the combination of rituximab with other monoclonal antibodies, immunomodulatory drugs, Bcl-2 inhibitors, and bortezomib. All of these agents face the challenge of optimal integration with rituximab. The strategies most likely to produce initial success will be those that incorporate rituximab in sensitive patients, as well as those that target patient populations with rituximab-refractory disease. Ideally, these studies will incorporate biologic correlates, such that the mechanisms of action and the patients most likely to benefit can be better defined. We discuss several combinations, their rationale, and the clinical evidence that justifies further evaluation.

Non-Hodgkin's lymphoma of mucosa-associated lymphoid tissue

The concept of mucosa-associated lymphoid tissue (MALT) lymphomas was introduced by Isaacson and Wright [Cancer 1983; 52:1410-1416] in 1983. After more than 20 years of clinical research MALT lymphomas are now recognized as a distinct subtype of non-Hodgkin's lymphoma (NHL) with unique pathogenic, histological, and clinical features. Although this subtype of NHL occurs frequently, optimal management remains elusive. This manuscript reviews features of the clinical presentation, diagnosis, pathology, molecular characteristics, and management of both gastric and non-gastric MALT lymphoma.