Lack of association of conjunctival MALT lymphoma with Chlamydiae or Helicobacter pylori in a cohort of Chinese patients.

Feb 2012

Cai JP, Cheng JW, Ma XY, Li YZ, Li Y, Huang X, Wei RL.

Source

Department of Ophthalmology, Shanghai Changzheng Hospital, 2nd Military Medical University, Shanghai, China.

Abstract

Background:

This study was conducted to detect microbial pathogens in conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma specimens in an attempt to determine possible associations between conjunctival MALT lymphoma and microbial infections.

Material/Methods:

Using PCR technique, freshly obtained tumor specimens from 16 cases of conjunctival MALT lymphoma, as confirmed by postoperative pathology, were analyzed for DNA of Chlamydia psittaci (C. psittaci), Chlamydia trachomatis (C. trachomatis), Chlamydia pneumoniae (C. pneumoniae) and Helicobacter pylori (H. pylori). Synthetic C. psittaci, C. trachomatis, C. pneumoniae and H. pylori DNA were used as positive control, and blank plasmid DNA as negative control.

Results:

Electrophoresis showed that no bands corresponding to the positive control were observed in the specimens, indicating that no DNA of the 4 microorganisms was detected in the specimens of the 16 cases of conjunctival MALT lymphoma.

Conclusions:

The PCR technique was able to detect the positive control quickly and accurately, but the results of PCR in analyzing the 16 specimens were negative, indicating that there is no association between conjunctival MALT lymphoma and the 4 microorganisms in Chinese patients.

PubMed

Antibiotics Effective in Treatment of MALT Lymphoma

Antibiotics Effective in Treatment of MALT Lymphoma

Researchers from Taiwan have reported that treatment of Helicobacter pylori (H. pylori) infection with antibiotics is effective against early-stage, low-grade mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach as well as high-grade transformed tumors. The details of this study appeared in the September 21, 2005, issue of the Journal of the National Cancer Institute .

Researchers have long known that H. pylori is associated with a certain type of low-grade non-Hodgkin’s lymphoma referred to as MALT lymphoma. MALT lymphoma develops outside of lymph nodes, most commonly in the stomach, salivary glands, lungs, or thyroid. Treatment of H. pylori infection with antibiotics results in complete disappearance of lymphoma in some patients with early-stage MALT lymphoma of the stomach.

In order to further assess the role of antibiotics in the treatment of patients with early-stage MALT lymphoma of the stomach, researchers in Taiwan evaluated two groups of patients. One group had low-grade MALT lymphoma, while the other had high-grade transformed lymphoma.

The patients with high-grade lymphoma had diffuse large B-cell lymphoma (DLBCL) with features of MALT. Some have speculated that DLBCL(MALT) lymphoma is not dependent on H. pylori and will not be affected by antibiotic treatment.

A large majority of both groups of patients were infected with Helicobacter pylori —94% of the patients with low-grade lymphoma and 100% of the patients with high-grade lymphoma.

Patients were treated with two weeks of antibiotics. The antibiotics were highly effective in both groups:

Antibiotics eliminated the H. pylori infection in 97% of the low-grade patients.

H. pylori infection was eliminated in 92% of the high-grade patients.

Among those whose infection was eliminated:

80% of patients with low-grade lymphoma experienced a complete disappearance of detectable lymphoma.

64% of patients with high-grade lymphoma had a complete disappearance of their disease.
None of the patients who were initially negative for H.pylori and none who had persistent infection after antibiotic treatment experienced a complete disappearance of lymphoma. After roughly five years of follow-up, lymphoma recurred in three (13%) of the patients with low-grade lymphoma; none of the patients with high-grade lymphoma had a recurrence.
The researchers conclude that antibiotic treatment of H. pylori infection is effective for both low-grade MALT lymphoma of the stomach as well as DLBCL(MALT). They recommend additional studies to confirm that antibiotics are an appropriate first-line treatment for early stage, H. pylori-positive DLBCL(MALT).

Comments: These are very interesting results and it will be important to confirm these observations in American patients.

Reference: Chen L-T, Lin J-T, Tai JJ et al. Long-term results of anti-Helicobacter pyloritherapy in early-stage gastric high-grade transformed MALT lymphoma. Journal of the National Cancer Institute . 2005;97:1345-1353.

CancerConsultants