Risk of Second Cancer in Nongastric Marginal Zone B-Cell Lymphomas of Mucosa-Associated Lymphoid Tissue: A Population-Based Study from Northern Italy

Characterization of Second Primary Malignancies in Mucosa-Associated Lymphoid Tissue Lymphomas: A SEER Database Interrogation

INTRODUCTION

Second primary malignancies (SPMs) are long-term complications in cancer survivors. Mucosa-associated lymphoid tissue (MALT) lymphomas are indolent extra-nodal marginal zone lymphomas, the majority of which typically have long-term survival. In this study, we investigated the incidence and pattern of SPMs in adult patients diagnosed with MALT lymphomas between January 2000 and December 2016.

METHODS

Using the SEER-18 database and multiple primary standardized incidence ratio (MP-SIR) session of SEER stat software for statistical analysis, we assessed SPMs in MALT lymphomas.

RESULTS

During this time, a total of 12,500 cases of MALT lymphomas were diagnosed, of which 1466 patients developed 1626 SPMs (O/E ratio: 1.48, 95% CI:1.41-1.55, P<.001). The median latency period for development of SPMs was 54 months (range 6-201 months). Secondary non-Hodgkin lymphomas, as defined by SEER as distinct from the primary lymphoma, was the most common SPM with 299 cases, followed by lung cancer (O/E ratio: 6.15, 95% CI:5.47-6.89, P<.0001). There were 898 SPMs that developed between 6- 59 months (O/E ratio: 1.47, 95% CI:1.37-1.57, P<.0001) and 728 after 60 months latency (O/E ratio: 1.5, 95% CI:1.39-1.61, P<.0001) after diagnosis of the primary MALT lymphomas. An increased incidence of both solid and hematologic cancers occurred in patients as early as 6 months after diagnosis of MALT lymphoma.

CONCLUSION

These findings indicate that despite the indolent nature of most MALT lymphomas, there is an increased risk for SPMs warranting long-term follow up.

[Pulmonary malt lymphoma]

This review will describe the current knowledge in the pathophysiology, diagnosis, prognosis and treatment of pulmonary MALT (Mucosa Associated Lymphoid Tissue) lymphoma. Pulmonary MALT lymphomas are low-grade B cell lymphoma and are the most frequent lymphomas arising from the lung. Tumour cells arise from mucosa associated lymphoid tissue. Unlike other sites, no pathogen has been associated with pulmonary location of MALT lymphoma. However addictive translocations involving the MALT1 gene are frequently evidenced Patients are frequently asymptomatic and present with a chronic alveolar opacity. Diagnosis requires histology that may be retrieved by minimally invasive procedures during bronchial endoscopy or by CT scan guided percutaneous biopsies. Prognosis is good and treatment may vary with abstention, surgery, radiotherapy, immunotherapy or chemotherapy.

Risk of second malignancies in patients with gastric marginal zone lymphomas of mucosa associate lymphoid tissue (MALT)

BACKGROUND

It is controversial whether patients with gastric marginal zone lymphomas of mucosa associated lymphoid tissue (MALT) have higher risk of second malignancies. The aim of this study was to define the risk of second malignancies in these patients.

METHODS

We analyzed prospective follow-up data of 146 consecutive patients with gastric MALT lymphoma treated at Aichi Cancer Center Hospital and compared the incidence of second malignancies with that in the general population. We calculated the standardized incidence ratio (SIR), using age- and sex-specific incidence rates from the Aichi Cancer Registry.

RESULTS

The median follow-up period was 74 months. A total of 27 tumors occurred in 22 patients (15.1%), including 19 solid tumors. Of these, nine tumors were detected concomitantly with, and 18 tumors following, the diagnosis of gastric MALT lymphoma. Four patients had two second malignancies each. For the entire group, the SIR of an additional malignancy was 3.39 (95% confidence interval [CI] 2.11-4.66). An increased incidence of solid tumors (SIR 2.91 [1.60-4.22]) and hematologic malignancies (SIR 5.54 [1.70-9.38]) were seen. In addition, there was increased risk for development of second malignancies during follow up (SIR 2.26 [1.21-3.30]). Chemotherapy for treatment of MALT was an independent risk factor for second malignancies (age-sex adjusted hazard ratio 3.98 [1.47-10.79].

CONCLUSIONS

Compared with the general population, patients with gastric MALT lymphoma are at increased risk for second malignancies, including gastric cancer.

Risk for second malignancies in non-Hodgkin's lymphoma survivors: a meta-analysis

BACKGROUND

Late side-effects are becoming an important issue in non-Hodgkin's lymphoma (NHL) survivors. We intended to estimate pooled relative risk (RR) of secondary malignant neoplasms (SMNs), to evaluate site-associated RR and the impact of different treatments.

DESIGN

We carried out an electronic search of Medline and EMBASE seeking articles investigating the risk of SMNs and reporting RR measures. The studies were evaluated for heterogeneity before meta-analysis and for publication bias. Pooled RRs were estimated using fixed- and random-effects models.

RESULTS

A total of 23 studies met the inclusion criteria. Pooled RRs of SMNs overall and for solid tumors were 1.88 and 1.32, respectively. We found an excess of risk for several specific cancer sites. Radiotherapy alone did not increase the risk for SMNs, while chemotherapy and combined treatments augmented the RR. Regression analyses revealed a positive significant association for all SMNs with total body irradiation, and for solid SMNs with younger age. No publication bias was observed.

CONCLUSIONS

Our results indicate that NHL patients experience a higher risk for SMNs than the general population and that various treatments have different impact on RR. More information will be necessary to evaluate possible interactions with genetic susceptibility and environmental exposure.