Expert Consensus Recommendations on Biomarker Testing in Metastatic and Nonmetastatic NSCLC in Asia.

INTRODUCTION: Most published guidelines for genomic biomarker testing in NSCLC reflect the disease epidemiology and treatments readily available in Europe and North America. Nevertheless, 60% of annual global NSCLC cases occur in Asia, where patient characteristics, tumor molecular profiles, and treatments vary greatly from the Western world. For example, mutations in the EGFR occur at a higher prevalence in Asia than in other world regions. Although medical associations such as the International Association for the Study of Lung Cancer, European Society for Medical Oncology, and American Society of Clinical Oncology have described principles for tumor genomic biomarker testing in NSCLC, there is a need for recommendations specific for Asia. METHODS: This report provides consensus recommendations for NSCLC biomarker testing from Asian lung cancer experts for clinicians working in Asia to improve patient care. Biomarker testing approaches for actionable genetic alterations in EGFR, ALK, ROS1, and others are discussed. RESULTS: These recommendations are divided into nonmetastatic and metastatic forms of adenocarcinoma and squamous cell carcinoma. Owing to the higher prevalence of EGFR mutations in Asia, the experts emphasized the need for EGFR testing to include not just common mutations (exon 19 deletions and L858R substitutions) but also other uncommon EGFR mutations. In addition to the assessment of biomarkers in the tumor tissue, the role of assessing tumor biomarkers by liquid biopsy is discussed. CONCLUSION: This consensus provides practical recommendations for biomarker testing in nonmetastatic and metastatic Asian NSCLC patients.

Genomic signatures define three subtypes of EGFR-mutant stage II-III non-small-cell lung cancer with distinct adjuvant therapy outcomes.

The ADJUVANT study reported the comparative superiority of adjuvant gefitinib over chemotherapy in disease-free survival of resected EGFR-mutant stage II-IIIA non-small cell lung cancer (NSCLC). However, not all patients experienced favorable clinical outcomes with tyrosine kinase inhibitors (TKI), raising the necessity for further biomarker assessment. In this work, by comprehensive genomic profiling of 171 tumor tissues from the ADJUVANT trial, five predictive biomarkers are identified (TP53 exon4/5 mutations, RB1 alterations, and copy number gains of NKX2-1, CDK4, and MYC). Then we integrate them into the Multiple-gene INdex to Evaluate the Relative benefit of Various Adjuvant therapies (MINERVA) score, which categorizes patients into three subgroups with relative disease-free survival and overall survival benefits from either adjuvant gefitinib or chemotherapy (Highly TKI-Preferable, TKI-Preferable, and Chemotherapy-Preferable groups). This study demonstrates that predictive genomic signatures could potentially stratify resected EGFR-mutant NSCLC patients and provide precise guidance towards future personalized adjuvant therapy.

A Novel Combined Conjugate Therapeutic Cancer Vaccine, Recombinant EGF-CRM197, in Patients With Advanced Solid Tumors: A Phase I Clinical Study.

INTRODUCTION: The therapeutic cancer vaccine recombinant Epidermal Growth Factor (EGF)-CRM197 is a novel combined conjugate EGF with CRM197 as a carrier protein. Immunization with the EGF-CRM197 vaccine can induce high levels of neutralizing anti-EGF antibodies that inhibit EGF/EGFR signaling and thereby suppress growth of tumors that rely on this signaling pathway. Herein, we characterize the humoral immune responses elicited by the recombinant EGF-CRM197 vaccine in patients with advanced solid tumors in a phase I clinical trial and assess the safety, tolerability, and immunogenicity of this vaccine (CTR20190473). METHODS: A total of 16 subjects were enrolled in this study. Under 6 + 3 design, patients in each dosing cohort were administrated subcutaneously at a dosage of 0.4 mg, 0.8 mg, and 1.6 mg, respectively. The patients received vaccinations for immune induction (once a week for 4 consecutive weeks) and booster vaccinations (once every 4 weeks). Safety evaluation was performed 1 week after the immune induction. Booster vaccination was given until the occurrence of disease progression, intolerance, withdrawal of informed consent by the patient, or negative result of anti-EGF test after two booster vaccinations. RESULTS: Vaccination with EGF-CRM197 is safe and well-tolerated in patients with advanced solid tumors. Adverse reactions at the injection site were the most common adverse events (AEs) in recipients. No severe adverse reactions post vaccination were observed in the present study. Vaccinated patients developed a robust neutralizing antibody response triggered by EGF-CRM197 that significantly reduced the levels of EGF in serum. For lung cancer patients who were super good antibody responders (sGAR) to EGF-CRM197, the median progress-free survival (PFS) was 4.83 months, significantly longer than that of the good antibody responder (GAR) patients with lung cancer whose median PFS was 2.10 months (P=0.0018). The median overall survival (OS) of GAR lung cancer patients was 10.67 months while the OS) for sGAR lung cancer patients was not reached until analysis was performed. The median follow-up of the sGAR lung cancer patients was 14.6 months. CONCLUSION: Our study demonstrates that the recombinant EGF-CRM197 therapeutic cancer vaccine can induce a good immune response in patients with advanced solid tumors and is safe and well tolerated, which ensures further clinical development of the vaccine for extending the survival time of EGF-CRM197 sensitive patients with advanced solid tumors. CLINICAL TRIAL REGISTRATION: http://www.chinadrugtrials.org.cn, identifier CTR20190473, EGF-CRM197.

Gefitinib Versus Vinorelbine Plus Cisplatin as Adjuvant Treatment for Stage II-IIIA (N1-N2) EGFR-Mutant NSCLC: Final Overall Survival Analysis of CTONG1104 Phase III Trial.

PURPOSE: ADJUVANT-CTONG1104 (ClinicalTrials.gov identifier: NCT01405079), a randomized phase III trial, showed that adjuvant gefitinib treatment significantly improved disease-free survival (DFS) versus vinorelbine plus cisplatin (VP) in patients with epidermal growth factor receptor (EGFR) mutation-positive resected stage II-IIIA (N1-N2) non-small-cell lung cancer (NSCLC). Here, we report the final overall survival (OS) results. METHODS: From September 2011 to April 2014, 222 patients from 27 sites were randomly assigned 1:1 to adjuvant gefitinib (n = 111) or VP (n = 111). Patients with resected stage II-IIIA (N1-N2) NSCLC and EGFR-activating mutation were enrolled, receiving gefitinib for 24 months or VP every 3 weeks for four cycles. The primary end point was DFS (intention-to-treat [ITT] population). Secondary end points included OS, 3-, 5-year (y) DFS rates, and 5-year OS rate. Post hoc analysis was conducted for subsequent therapy data. RESULTS: Median follow-up was 80.0 months. Median OS (ITT) was 75.5 and 62.8 months with gefitinib and VP, respectively (hazard ratio [HR], 0.92; 95% CI, 0.62 to 1.36; P = .674); respective 5-year OS rates were 53.2% and 51.2% (P = .784). Subsequent therapy was administered upon progression in 68.4% and 73.6% of patients receiving gefitinib and VP, respectively. Subsequent targeted therapy contributed most to OS (HR, 0.23; 95% CI, 0.14 to 0.38) compared with no subsequent therapy. Updated 3y DFS rates were 39.6% and 32. 5% with gefitinib and VP (P = .316) and 5y DFS rates were 22. 6% and 23.2% (P = .928), respectively. CONCLUSION: Adjuvant therapy with gefitinib in patients with early-stage NSCLC and EGFR mutation demonstrated improved DFS over standard of care chemotherapy. Although this DFS advantage did not translate to a significant OS difference, OS with adjuvant gefitinib was one of the longest observed in this patient group compared with historic data.

Frequency of the acquired resistant mutation T790 M in non-small cell lung cancer patients with active exon 19Del and exon 21 L858R: a systematic review and meta-analysis.

BACKGROUND: Although EGFR-TKI is the preferred treatment for NSCLC patients with sensitive mutations, subsequent drug resistance is almost inevitable. The specific mechanisms of EGFR-TKI drug resistance can be identified through repeat biopsy. METHODS: To better understand the clinical characteristics of TKI resistance in NSCLC patients, we retrospectively reviewed studies of acquired TKI drug resistance using repeat biopsy from the last decade. The relevant literature was retrieved from January 2005 to August 2015 in the databases Medline and Embase. The search terms were NSCLC or non-small cell lung cancer and T790 M. RESULTS: A total of 478 patients with NSCLC tested by repeated biopsy were confirmed to have acquired TKI resistance. Analysis indicated that 240 patients (50.21%) of the 478 patients with acquired TKI drug resistance had the T790 M mutation. The detection rate of T790 M in different repeat biopsy sites was also different, with the highest positive rate in the lymph nodes (60%) and the lowest detection rate in cerebrospinal fluid (less than 5%). In addition, patients with T790 M had longer overall survival compared to those without the mutation (P < 0.05). Of the 240 patients with T790 M mutations, 213 patients showed results consistent with the mutation analysis before TKI treatment, and the rate of patients with the L858R point mutation along with the T790 M mutation was lower than that of patients with the exon 19 deletion (36.42% to 58.30%). CONCLUSIONS: T790 M occurred more frequently in patients with the exon 19 deletion than in those with exon 21 L858R, which gave the survival benefit of the T790 M mutation and may explain why patients with the exon 19 deletion had an improved overall survival.

High Expression of Cathepsin E is Associated with the Severity of Airflow Limitation in Patients with COPD.

BACKGROUND: It was reported that Cathepsin E (Cat E) plays a critical role in antigen processing and in the development of pulmonary emphysema. The aim of this study was to investigate the role of Cat E and airflow limitation in the pathogenesis of COPD. METHODS: Sixty-five patients with COPD, 20 smoking control subjects without COPD and 15 non-smoking healthy control subjects were enrolled. Cat E and EIC (Elastase inhibitory capacity) expressions were measured by ELISA in sputum and serum samples and compared according to different subgroups. RESULTS: Cat E concentrations were significantly higher in patients with COPD than smoking control and non-smoking control subjects (P < 0.01). The levels of CatE were inversely correlated with FEV1% predicted in COPD patients (r = -0.95, P < 0.01). The levels of EIC were inversely positively correlated with FEV1% predicted in COPD patients (r = 0.926, P < 0.01). Levels of Cat E were also inversely correlated with the levels of EIC (r = -0.922, P < 0.01). CONCLUSIONS: Cat E contributes to the severity of airflow limitation during progression of COPD.

High feasibility of liquid-based cytological samples for detection of EGFR mutations in Chinese patients with NSCLC.

BACKGROUND: Activating mutations of epidermal growth factor receptor (EGFR) could predict response to tyrosine kinase inhibitor (TKI) treatment in patients with non-small cell lung cancer (NSCLC). However, the detection of EGFR mutation is frequently challenging in clinical practice for the lack of tumor tissue. The aim of this study was to investigate the feasibility of performing EGFR mutation testing on various types of liquid-based cytology (LBC) samples. MATERIALS AND METHODS: A total of 434 liquid-based cytology samples were collected from March 2010 and November 2013. Among them, 101 with diagnosis of lung adenocarcinoma had paired surgically resected specimens. The ADx Amplification Refractory Mutation System (ADx-ARMS) was used to determine EGFR mutation status both in LBC and resected samples. RESULTS: All liquid-based cytology samples were adequate for EGFR mutation analysis. The mutation rate was 50.5% in the 434 NSCLC patients with LBC samples and the incidence rates of EGFR mutation were consistent among different specimens. We also detected EGFR positives in 52.5% (53/101) patients with paired histologic specimens. The concordance rate of EGFR mutation between LBC samples and paired histologic specimens was 92.1%. CONCLUSIONS: Our results suggest that liquid-based cytology samples are highly reliable for EGFR mutation testing in patients with NSCLC.

Efficacy of first-line chemotherapy affects the second-line setting response in patients with advanced non-small cell lung cancer.

BACKGROUND: Chemotherapy is the mainstay of treatment for the majority of patients with advanced non- small cell lung cancer (NSCLC) without driver mutations and many receive therapies beyond first-line. Second- line chemotherapy has been disappointing both in terms of response rate and survival and we know relatively little about the prognostic factors. MATERIALS AND METHODS: One thousand and eight patients with advanced NSCLC who received second-line chemotherapy after progression were reviewed in Shanghai Pulmonary Hospital, China, from September 2005 to July 2010. We analyzed the effects of potential prognostic factors on the outcomes of second-line chemotherapy (overall response rate, ORR; progression free survival, PFS; overall survival, OS). RESULTS: The response and progression free survival of first-line chemotherapy affects the ORR, PFS and OS of second-line chemotherapy (ORR: CR/PR 15.4%, SD 10.1%, PD2.3%, p<0.001; PFS: CR/PR 3.80 months, SD 2.77 months, PD 2.03 months, p<0.001; OS: CR/PR 11.60 months, SD 10.33 months, PD 6.57 months, p=0.578, p<0.001, p<0.001, respectively). On multivariate analysis, better response to first-line therapy (CR/PR: HR=0.751, p=0.002; SD: HR=0.781, p=0.021) and progression within 3-6 months (HR=0.626, p<0.001), together with adenocarcinoma (HR=0.815, p=0.017), without liver metastasis (HR=0.541, p=0.001), never-smoker (HR=0.772, p=0.001), and ECOG PS 0-1 (HR=0.745, p=0.021) were predictors for good OS following second- line chemotherapy. CONCLUSIONS: Patients who responded to first-line chemotherapy had a better outcome after second-line therapy for advanced NSCLC, and the efficacy of first-line chemotherapy, period of progression, histology, liver metastasis, smoking status and ECOG PS were independent prognostic factors for OS.

[Effect of Wnt signaling suppression on gefitinib in non small cell lung cancer cell lines].

OBJECTIVE: To explore the effect of Wnt signaling suppression on proliferation of non small cell lung cancer to gefitinib, and its related mechanisms. METHODS: PC9 and PC9/AB2 cells of both gefitinib sensitive and resistant were treated with different concentrations of gefitinib, and the proliferation index was measured using CCK8 kit. The members of Wnt signaling pathway were detected by Western blot. Dual luciferase reportor gene assay (TOP Flash) was used to document the transcriptional level of ß-catenin. ß-catenin siRNA was transfected into PC9/AB2 cells to suppress the Wnt signaling transcription, followed by treatment with different concentrations of gefitinib. Western blot was then used to detect the expression of EGFR and its downstream signaling after inhibit the expression of ß-catenin. RESULTS: Treating with different concentrations of gefitinib, the resistance of PC9/AB2 cells to gefitinib was significantly increased (P < 0.05). The members of Wnt signaling expressed at higher level in PC9/AB2 cells than in PC9 cells (t = 24.590, P = 0.000). TOP Flash examination showed that the endogenous transcriptional activity of Wnt signaling was higher in PC9/AB2 cell than that in PC9 cell (t = 4.983, P = 0.008). Compared with the negative control group, apoptotic rate and sensitivity to gefitinib significantly increased in interfered group (P < 0.05). The expression of p-ERK1/2 significantly decreased after Wnt signaling suppression, although other proteins showed no significant alterations. CONCLUSION: Suppressing the activity of Wnt signaling can partly reverse the celluar resistance to gefitinib in non small cell lung cancer.

Serum cytokine levels in patients with advanced non-small cell lung cancer: correlation with clinical outcome of erlotinib treatment.

BACKGROUND: Serum expression of cytokines may provide information about the clinical outcome of advanced non-small cell lung cancer (NSCLC) patients. This study aimed to investigate the relationship between serum cytokine levels and the clinical outcome of erlotinib treatment in a second or third line setting in patients with advanced NSCLC. METHODS: A total of 162 patients with advanced NSCLC who received erlotinib as either second or third line therapy were enrolled in this study. Blood samples were collected before the initiation of erlotinib treatment, and the levels of IL-1, IL- 2R, IL-6, and tumor necrosis factor (TNF)-α were assessed by enzyme-linked immunosorbent assay (ELISA). Cutoff points were defined as the median levels of IL-1 (low (≥26.5 pg/ml) and high (>26.5 pg/ml)), IL-2R (low ( = 115 pmol/L) and high (>15 pmol/L)), IL-6 (low (≤49.5 pg/ml) and high (>49.5 pg/ml)), and TNF-α (low (≤48.5 pg/ml) and high (>48.5 pg/ml)). Kaplan-Meier analysis was used to estimate the survival time, and Cox regression analyses were used to correlate cytokines and baseline clinical characteristics with clinical outcomes, including time to progression (TTP) and overall survival (OS). RESULTS: Between January 2007 and May 2011, 162 patients were enrolled. Their median age was 58 years. In this group, 109 were males and 53 were females, 74 were former or current smokers and 88 were non-smokers. A total of 122 patients had adenocarcinoma, 27 had squamous cell carcinoma, and 13 had tumors with other types of histology. And 139 patients had an Eastern cooperative oncology group (ECOG) performance status of 0-1, while 23 scored at 2-3. Expression of IL-1, IL-2R, and IL-6 was not significantly associated with age, gender, ECOG performance status, smoking status, or histology and stage of tumor. Only TNF-α was associated with smoking status (P = 0.045). Survival analysis showed that patients with low levels of either IL-6 or TNF-α had a statistically longer TTP and OS than patients with high expression (P < 0.05). These cytokines remained significant upon multivariate analysis (P < 0.05). CONCLUSION: IL-6 or TNF-α may serve as potential predictive biomarker for the efficacy of erlotinib.

[Evaluation of endobronchial ultrasound-guided transbronchial needle aspiration in the diagnosis of hilar and mediastinal tumors].

OBJECTIVE: To explore the diagnostic values of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in patients with hilar and mediastinal tumors. METHODS: A total of 837 patients with chest CT or PET/CT confirmed mediastinal/hilar lymphadenopathy and or tumors in (or around) the trachea or bronchi, were evaluated by EBUS-TBNA examination. Pathological study or follow-up visit was carried out in the same period to make a final diagnosis, and therefore to verify the accuracy of EBUS-TBNA. RESULT: The study punctured 1631 lymph nodes totally, with an average of 1.95 times per case. The 4R group and the 7th group of lymph nodes accounted for 43% and 34%, respectively. The success rate of TBNA was 100%. The diagnosis rates of lung cancer was 94.11%, of which squamous cell carcinoma accounted for 19.22% (89 cases), adenocarcinoma 32.40% (150 cases), small cell carcinoma 23.54% (109 cases), non-small cell carcinoma of unknown histological type 9.50% (44 cases), adenosquamous carcinoma 7.56% (35 cases), and other types 7.78% (36 cases). The diagnosis rate of tuberculosis was 85.50%, and that of sarcoidosis was 55.88%. The overall sensitivity of EBUS-TBNA was 94.02%, specificity 100%, positive predictive value 100%, negative predictive value 61.91%, and the accuracy was 94.56%. Besides mild bleeding in the puncture site, no other complications occurred, and there were no severe complications such as pneumothorax, pneumomediastinum, or major vascular injury. CONCLUSION: EBUS-TBNA is of high value as a minimally invasive, convenient, and low-risk procedure for the diagnosis of mediastinal and hilar lymphadenopathy and tumors.

[The ultrastructural features of sputum deposition and its value in the diagnosis of pulmonary alveolar proteinosis].

OBJECTIVE: To investigate the ultrastructural features of sputum deposition (SD) and its value in the diagnosis of pulmonary alveolar proteinosis (PAP). METHODS: Seven patients with PAP diagnosed by lung biopsy and cytology were enrolled in this study. The patients consisted of 5 men and 2 women, whose median age was 48 years (range 36 to 73). SD and bronchoalveolar lavage fluid (BALF) sediment were made into ultrathin sections and observed under transmission electron microscope (TEM), respectively. Seven cases of control group composed of 4 men and 3 women whose median age was 49 years (range 39 to 68) including 3 cases of bacterial pneumonia, two cases of COPD and 2 cases of exudative pulmonary tuberculosis. Each SD was made into ultrathin section, and compared with the experimental group. RESULTS: In PAP group, Periodic acid-schiff (PAS) staining was performed on 7 sputum smears and none of them was tested positive for any components with diagnostic interest. Four cases from the 7 paraffin-embed sections of BALF sediment by microscopic examination suggested PAP. Under TEM, BALF sediment showed that many lamellar bodies existed in and outside alveolar epithelial cells, and 5 specimens were consistent with PAP diagnosis. Compared with BALF sediment, SD had apparent degeneration with more myelin phagosomes in the cytoplasm of macrophages, more lamellar bodies in alveolar epithelial cells, and lots of lamellar bodies in the shape of concentric circle in the extracellular spaces. Four from the 7 SD samples were consistent with the diagnosis of PAP. No significant difference was found between SD and BALF in the diagnosis of PAP by electronic examination (P > 0.05). In the 7 cases of control group no drifting osmiophilic lamellar bodies in extracellular space were detected. CONCLUSIONS: The osmiophilic lamellar bodies with diagnostic value were found in SD and BALF of patients with PAP. TEM of SD in combination with clinical manifestations and radiologic findings can make a definitive diagnosis of PAP, especially for those patients who have contraindications to lung biopsy and lung lavage.

Individualized Chemotherapy in Advanced NSCLC Patients Based on mRNA Levels of BRCA1 and RRM1.

OBJECTIVE: Experimental evidence suggests that the overexpression of breast cancer-specific tumor suppressor protein 1 (BRCA1) gene enhances sensitivity to docetaxel and resistance to cisplatin and ribonucleotide reductase M1 (RRM1) gene overexpression enhances resistance to gemcitabine. To further examine the effect of BRCA1 and RRM1 mRNA levels on outcome in advanced non-small cell lung cancer (NSCLC), we performed this non-randomized phase II clinical trial which tested the hypothesis that customized therapy would confer improved outcome over non-customized therapy. METHODS: RNA was isolated from fresh tumor tissue. Patients received chemotherapy regimen based on their BRCA1 and RRM1 mRNA levels: both low-cisplatin plus gemcitabine (GP); both high-vinorelbine plus cisplatin (NP); BRCA1 low and RRM1 high-cisplatin plus docetaxel (TP); BRCA1 high and RRM1 low-vinorelbine plus gemcitabine (GN). RESULTS: From Dec 2005 to Nov 2008, 94 metastatic and locally advanced NSCLC patients from our institute were enrolled in this study. The median age was 58 years old. Among them, 21 patients received GP, 30 patients received TP and 43 patients received NP chemotherapy. GP group had a higher response rate, and longer median time to progression (TTP) and median overall survival (OS) time than the other 2 groups. The response rates in the GP, TP and NP groups were 42.9%, 36.7% and 27.9%, respectively (P=0.568). The median TTP was 5.6, 5.0, 4.8 months (P=0.975), respectively, and the median OS time was 12.5, 11.0, 9.7 months (P=0.808), respectively. CONCLUSION: Chemotherapy customized according to BRCA1 and RRM1 expression levels is associated with higher response rate and longer TTP and OS time in the GP group. This suggests that BRCA1 and RRM1 mRNA levels could be used as biomarkers in individual therapy in NSCLC.

[Impact of erlotinib treatment on symptoms and quality of life in patients with advanced non-small-cell lung cancer].

OBJECTIVE: To investigate the impact of erlotinib as a second or third line treatment on the symptoms and quality of life (QOL) in patients with advanced non-small cell lung cancer (NSCLC). METHODS: Fifty patients with stage III b and IV NSCLC, treated previously with at least one regimen of platinum-based chemotherapy, received 150 mg of erlotinib orally, once a day till disease progression. QOL was assessed by European Organization for Research and Treatment of Cancer QLQ-C30 and the lung cancer module (QLQ-LC13). The primary end points for QOL analysis were time to deterioration of three common lung cancer symptoms: cough, dyspnea and pain. RESULTS: Among 47 evaluable cases, there were partial remission (PR) in 18 cases, stable disease (SD) in 21 cases, and progressive disease (PD) in 8 cases. After two cycles of treatment, the mean scores of global QOL and all 5 functioning scales except the cognitive function increased significantly (P < 0.05). Mean scores of major general symptoms, hypodynamia and anorexia, and disease-related symptoms alleviated significantly. Both response rates of five functioning and global QOL were more than 44% after erlotinib treatment. Response rates of major general symptoms and disease-related symptoms varied from 14% to 76%. Patients with complete or partial response likely had improvement in the QOL response (P < 0.05), and the time to major symptom deterioration in those were significantly longer (P < 0.001) than that in patients with stable or even progressive disease. CONCLUSION: Erlotinib is effective to improve not only survival, but also tumor-related symptoms and quality of life in patients with advanced NSCLC previously treated with cisplatin-contained regimens. The improvement in the quality of life is positively correlated with objective tumor response.

[The clinical diagnosis and analysis of pulmonary mucosa associated lymphoid tissue lymphoma].

OBJECTIVE: To improve the diagnosis of pulmonary mucosa associated lymphoid tissue (PMALT) lymphoma. METHOD: The clinical and radiographic data of 13 cases of pathology confirmed PMALT lymphoma admitted from June 1998 to June 2006 were respectively analyzed. RESULTS: There were 9 males and 4 females, with an average age of 55 years. The course of the disease was 1.5 - 108 months (average 14 months). Clinical features were nonspecific, with mild symptoms including cough, chest pain, breathlessness, hemoptysis, fever, and weight loss. Some cases were suspected in the routine physical examination. Chest radiography showed multiple lesions, commonly bilateral (7/13). The lesions were of varied manifestations, including masses (2/13), nodules (2/13), increased airspace consolidation with air bronchogram (9/13) and pleural fluid (4/13). Bronchial stenosis and inflammation (6/13) were present under bronchoscopy. CONCLUSIONS: PMALT is not common, and tends to affect middle aged and older males. The disease progresses slowly and the clinical features are nonspecific.