This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Alert me to new issues of the journal Save to my personal folders Download to citation manager Rights & Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Laszlo, D. Articles by Martinelli, G. Search for Related Content PubMed Articles by Laszlo, D. Articles by Martinelli, G. Social Bookmarking                            What's this?

In Reply:

Haematoncology Division, European Institute of Oncology, Milan, Italy
Pathology Division, European Institute of Oncology, Milan, Italy
Department of Onocology, Oncology Institute of Southern Switzerland, Bellinzona, Switzerland
Haematoncology Division, European Institute of Oncology, Milan, Italy

We thank Salar et al for their interest and comments about our article concerning clinical activity of anti-CD20 monoclonal antibody in resistant/refractory gastric mucosa-associated lymphoid tissue (MALT) lymphomas.

This entity represents clinical problems: The first issue is to identify a prognostic marker to predict the response to therapy. The second is to investigate whether an alternative, safer therapeutic strategy could be proposed instead of the standard approach (ie, radiation therapy, chemotherapy, gastrectomy). Finally, the clinical relevance of a persistent monoclonality in patients achieving a histologic complete remission after treatment still needs to be clarified.

The role of persistent molecular disease after treatment in gastric MALT lymphomas has been investigated by Bertoni et al,¹ but it is still questionable regarding its intrinsic value.

We agree with the authors, who suggest that the evaluation of the t(11;18) translocation by reverse transcriptase polymerase chain reaction may be a highly specific and sensitive method for monitoring minimal residual disease in MALT lymphoma patients. Interestingly, they found t(11;18) positive cells in their three patients after therapy. We recently analyzed by conventional PCR of immunoglobulin heavy chain (IgH) at FR2 and FR3A 56 gastric biopsies obtained during a mean follow-up period of 45 months from four patients included in the present study and showing a 18q21 locus translocation at diagnosis (unpublished data). Interestingly, in line with previous findings in patients treated by antibiotic therapy only,² a monoclonal rearrangement of the IgH gene was found in 78% of the cases. In particular, at least a biopsy obtained from every endoscopic examination resulted positive by this method. We are now sequencing the products of the rearrangement, in order to compare with those found in the diagnostic biopsy. Interphase fluorescence in situ hybridization analysis after immunofluorescence with an anti-CD20 antibody was also performed in 18 biopsies showing lymphoid aggregates composed by more than 10 lymphocytes, and showed a 18q21 locus translocation in 11% of the cases only, thus further confirming that reverse transcriptase polymerase chain reaction may be considered a method more reliable than interphase fluorescence in situ hybridization for evaluating the t(11;18) translocation in MALT lymphoma patients showing clinical and morphologic complete remission.

From a clinical point of view, the efficacy of maintenance treatment with rituximab has been demonstrated in follicular lymphomas,^3,4 but no data are available about marginal-zone non-Hodgkin's lymphoma. Moreover the best maintenance timing with rituximab (ie, once every two months v other modality) has to be investigated yet.

Radioimmunotherapy (ibritumomab tiuxetan) that combines the effect of the monoclonal anti-CD20 antibody with the targeted radiotherapy could be an intriguing alternative strategy, and a study about this new therapeutic approach in this field is still ongoing at our institute.

Authors' Disclosures of Potential Conflicts of Interest

The authors indicated no potential conflicts of interest.

REFERENCES

1. Bertoni F, Conconi A, Capella C, et al: Molecular follow-up in gastric mucosa-associated lymphoid tissue lymphomas: Early analysis of the LY03 cooperative trial. Blood 99:2541-2544, 2002[Abstract/Free Full Text]

2. Thiede C, Wundisch T, Alpen B, et al: Long-term persistence of monoclonal B cells after cure of Helicobacter pylori infection and complete histologic remission in gastric mucosa-associated lymphoid tissue B-cell lymphoma. J Clin Oncol 15:1600-1609, 2001

3. Hainsworth J, Litchy S, Shaffer D, et al: Maximizing therapeutic benefit of rituximab: Maintenance therapy versus re-treatment at progression in patients with indolent non-Hodgkin's lymphoma—A randomized phase II trial of the Minnie Pearl Cancer Research Network. J Clin Oncol 23:1088-1095, 2005[Abstract/Free Full Text]

4. Hainsworth J: Prolonging remission with rituximab maintenance therapy. Sem Oncol 31:27-32, 2004 (suppl 2)

CiteULike    Complore    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Alert me to new issues of the journal Save to my personal folders Download to citation manager Rights & Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Laszlo, D. Articles by Martinelli, G. Search for Related Content PubMed Articles by Laszlo, D. Articles by Martinelli, G. Social Bookmarking                            What's this?