Multipurpose ultrasonographic characteristics of primary uveal MALT lymphoma.

PURPOSE: To investigate the ultrasonographic features in patients with primary uveal mucosa-associated lymphoid tissue (MALT) lymphoma. METHODS: Medical records of 12 patients (13 eyes) diagnosed with primary uveal MALT lymphoma between September 2014 and September 2021 were retrospectively reviewed. Ultrasonography, B-scan ultrasonography, color Doppler flow imaging, and ultrasound biomicroscopy findings were retrieved from the medical records. RESULTS: Mean age of the included patients was 59.4 ± 8.6 years. Typical ultrasonographic features of the choroidal infiltrates were flat, diffuse, and thickened, with low and homogenous internal reflectivity and with rich arterial blood flow from posterior ciliary arterioles. The mean thickness of the choroidal infiltrates was 1.34 ± 0.68 mm (n = 13). Most of the affected eyes had posterior episcleral extensions, with a mean thickness of 1.66 ± 1.21 mm (n = 12). Typical crescent-like posterior episcleral extensions were detected in nine eyes (69.2%). In six eyes, the blood flow from the choroidal infiltrates communicated with the episcleral extensions. In the ciliary body, the mean thickness of the infiltrates was 1.08 ± 0.43 mm (n = 9), and seven eyes (77.8%) had 360° ring-like infiltrations. The initial best-corrected visual acuity (BCVA) was significantly correlated with the final BCVA after treatment (p < 0.001). CONCLUSION: Multipurpose ultrasonographic imaging revealed the unique characteristics of the primary uveal MALT lymphoma and is helpful in the diagnosis of this rare disease.

Rare lymphomas in routine practice - Treatment and outcome in marginal zone lymphoma in the prospective German Tumour Registry Lymphatic Neoplasms.

Owing to its heterogeneity and rarity, management of disseminated marginal zone B-cell lymphoma (MZL) remains largely understudied. We present prospective data on choice of systemic treatment and survival of patients with MZL treated in German routine practice. Of 175 patients with MZL who had been documented in the prospective clinical cohort study Tumour Registry Lymphatic Neoplasms (NCT00889798) collecting data on systemic treatment, 58 were classified as extranodal MZL of mucosa-associated lymphoid tissue (MALT) and 117 as non-MALT MZL. We analyzed the most commonly used first-line and second-line chemo(immuno)therapies between 2009 and 2016 and examined objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and prognostic factors for survival. Compared to patients with MALT MZL, those with non-MALT MZL more often presented with bone marrow involvement (43% vs. 14%), Ann Arbor stage III/IV (72% vs. 57%) and were slightly less often in good general condition (ECOG = 0; 41% vs. 47%). In German routine practice, rituximab-bendamustine for a median of 6 cycles was the most frequently used first-line (76%) and second-line treatment (36%), with no major differences between MZL subtypes. The ORR for patients encompassing any positive response was 81%. For patients with MALT and non-MALT MZL, respectively, 5-years PFS was 69% (95% CI 52%-81%) and 66% (95% CI 56%-75%), 5-years OS 79% (95% CI 65%-89%) and 75% (95% CI 66%-83%). Cox proportional hazards models showed a significantly increased risk of mortality for higher age in all patient groups. Our prospective real world data give valuable insights into the management and outcome of non-selected patients with MZL requiring systemic treatment and can help optimize therapy recommendations.

Primary marginal zone B-cell lymphoma of the cavernous sinus: a case report and review of the literature.

BACKGROUND: Primary lymphoma of the cavernous sinus is a rare form of extranodal non-Hodgkin lymphoma, of which very few cases have been reported in the published literature. This report presents the MRI findings with apparent diffusion coefficient (ADC) value in an exceedingly rare primary marginal zone B-cell lymphoma (MZBCL) of the cavernous sinus. CASE PRESENTATION: The case in this study is a 59-year-old immunocompetent male patient with a 2-month history of right ptosis and blurred vision. Right third cranial nerve palsy and binocular diplopia were observed upon neurological examination. Preoperative brain CT showed an extra-axial enhancing mass lesion in the right cavernous sinus. On MRI, ipsilateral internal carotid arterial encasement was noted without causing stenosis of the vessel. Isointense signal on T1-weighted and T2-weighted images, homogeneous contrast enhancement, and diffusion restriction were also observed. The mean ADC value of the tumor is 0.64 × 10-3 mm2/s (b value = 1000 s/mm2). Subtotal resection of the tumor was performed, and improvement of clinical symptoms were observed. The pathologic diagnosis of MZBCL was established by immunohistochemical examinations. CONCLUSIONS: Primary MZBCL of the cavernous sinus is exceedingly rare, and preoperative confirmation poses a major challenge with CT and conventional MRI only. In this case, preoperative quantitative ADC value is shown to offer valuable additional information in the diagnostic process.

Marginal zone lymphoma of the dura - two case reports with long-term follow-up.

Primary MALT lymphoma arising at the dura is a rare circumstance with no categorical therapeutic plan in literature. There are few reports available with different treatment courses. Here, we report two cases with a long-term follow-up after the same pattern of management and review the literature.

High throughput sequencing reveals high specificity of TNFAIP3 mutations in ocular adnexal marginal zone B-cell lymphomas.

The majority of ocular adnexal (OA) lymphomas (OAL) are extranodal marginal zone lymphomas (MZL). First high throughput sequencing (HTS) studies on OA-MZL showed inconsistent results and the distribution of mutations in reactive lymphoid lesions of this anatomic region has not yet been sufficiently addressed. We characterized OAL and lymphoid lesions of the OA by targeted HTS. The study included 34 OA-MZL, 11 chronic conjunctivitis, five mature small cell B-cell lymphomas spreading to the OA, five diseases with increase of IgG4+ plasma cells, three Burkitt lymphomas (BL), three diffuse large B-cell lymphomas (DLBCL), three mantle cell lymphomas, three idiopathic orbital inflammations/orbital pseudo tumors (PT), and three OA lymphoid hyperplasia. All cases were negative for Chlamydia. The mutational number was highest in BL and lowest in PT. The most commonly (and exclusively) mutated gene in OA-MZL was TNFAIP3 (10 of 34 cases). Altogether, 20 out of 34 patients harbored mutually exclusive mutations of either TNFAIP3, BCL10, MYD88, ATM, BRAF, or NFKBIE, or nonexclusive mutations of IRF8, TNFRSF14, KLHL6, and TBL1XR1, all encoding for NK-κB pathway compounds or regulators. Thirteen patients (38%) had, to a great part, mutually exclusive mutations of chromatin modifier-encoding genes: KMT2D, CREBBP, BCL7A, DNMT3A, EP300, or HIST1H1E. Only four patients harbored co-occurring mutations of genes encoding for NK-κB compounds and chromatin modifiers. Finally, PTEN, KMT2D, PRDM1, and HIST1H2BK mutations were observable in reactive lymphoid lesions too, while such instances were devoid of NF-κB compound mutations and/or mutations of acetyltransferase-encoding genes. In conclusion, 80% of OA-MZL display mutations of either NK-κB compounds or chromatin modifiers. Lymphoid lesions of the OA bearing NF-κB compound mutations and/or mutations of acetyltransferase-encoding genes highly likely represent lymphomas.

Trends of Incidence and Survival Rates of Mucosa-associated Lymphoid Tissue Lymphoma in the Korean Population: Analysis of the Korea Central Cancer Registry Database.

BACKGROUND: Extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT-lymphoma) is an extranodal lymphoma that occurs at various sites in the body. There is a limited understanding of the incidence and survival rates of MALT-lymphoma. To investigate the nation-wide incidence and survival rates of MALT-lymphoma in Korea during 1999-2017, the data on MALT-lymphoma were retrieved from the Korea Central Cancer Registry. METHODS: During the time period of 1999-2017, 11,128 patients were diagnosed with MALT-lymphoma. The age and sex of the patients and the Surveillance, Epidemiology, and End Results (SEER) summary stage of the tumor were analyzed, and the relative survival rates (RSRs) were calculated. RESULTS: The age-standardized incidence rates of MALT-lymphoma in 2017 among males and females were 1.53 and 1.61 per 100,000 individuals, respectively, whereas those in 1999 among males and females were 0.21 and 0.20, respectively in Korea. The RSRs were more than 97% at 10 years post-diagnosis between 1993 and 2017. The 5-year RSRs were 87.4%, 94.8%, 97.8%, and 98.6% during 1996-2000, 2001-2005, 2006-2010, and 2013-2017, respectively. Based on SEER summary staging, the 5-year RSRs during 2013-2017 were 100.3%, 90.8%, 91.3%, and 97.9% for patients with localized, regional, distant, and unknown stages of MALT-lymphoma, respectively. CONCLUSION: Although the incidence of MALT-lymphoma is low in Korea, it has been increasing in recent years. The prognosis of MALT-lymphoma is good even at advanced stages. These findings provide useful insights to clinicians about MALT-lymphoma and inform patients about the survival rate.

Front-line management of indolent non-Hodgkin lymphoma in Australia. Part 2: mantle cell lymphoma and marginal zone lymphoma.

Mantle cell lymphoma (MCL) and the marginal zone lymphoma (MZL) subtypes (nodal MZL, extra-nodal MZL of mucosa-associated lymphoid tissue (MALT lymphoma) and splenic MZL) are uncommon lymphoma subtypes, accounting for less than 5-10% of all non-Hodgkin lymphoma. The evidence base for therapy is therefore limited and enrolment into clinical trials is preferred. Outcomes for patients with MCL have been steadily improving mainly due to the adoption of more intense strategies in younger patients, the use of rituximab maintenance and the recent introduction of bendamustine in older patients. MZL is a more heterogeneous group of cancer with both nodal, extra-nodal and splenic subtypes. Extranodal MZL may be associated with autoimmune or infectious aetiologies, and can respond to eradication of the causative pathogen. Proton pump inhibitor plus dual antibiotics in Helicobacter pylori positive gastric MALT lymphoma is curative in many patients. Watchful waiting is appropriate in most patients with asymptomatic advanced stage disease, which tends to behave in a particularly indolent manner. Other options for symptomatic disease include splenectomy, chemoimmunotherapy with rituximab and, more recently, targeted therapies.

Frequent immunoglobulin G4 expression in a common variant of primary cutaneous marginal zone B-cell lymphoma.

Immunoglobulin (Ig)G4 expression was recently observed in a proportion of primary cutaneous marginal zone B-cell lymphoma (PCMZL) with plasmacytic differentiation. IgG4-related disease is characterised by polyclonal lymphoplasmacytic infiltration with IgG4 expression, storiform fibrosis and obliterative phlebitis in histopathology. Here we report three cases of common variants of PCMZL with predominant and varied IgG4 expression, suggesting there is an underlying clonal progression between these two entities.

[Possible contribution of disseminated Mycobacterium shigaense infection to development of splenic marginal zone lymphoma].

A 73-year-old male who underwent splenectomy was diagnosed with splenic non-caseating granuloma in May 201X, and sarcoidosis was disregarded from the differential diagnosis. Owing to the persisting inflammation, the patient was carefully followed up with no treatment. Four months post splenectomy, the patient was hospitalized due to progressive dyspnea. Chest computed tomography revealed an encapsulated pleural effusion and lymphocytic infiltration in the left lower lung, with subclavian and mediastinal lymphadenopathy. Although the patient was treated with antibiotics, his condition showed no improvement; therefore, prednisolone 40 mg was administered, resulting in lung lesion improvement. A re-examination of the tissue obtained from the previously removed spleen revealed splenic marginal zone lymphoma (SMZL), a specific low-grade, small B-cell lymphoma. As a result, the patient was treated with rituximab combined with chemotherapy. During the fifth course of the chemotherapy, a subcutaneous abscess appeared in the cervical region, and Mycobacterium shigaense was isolated from the pus discharge, suggesting that the splenic granulomatous lesion formed due to M.shigaense, and dissemination of the Mycobacterium infection occurred following splenectomy and chemotherapy, when the patient was immunosuppressed. Overall, we consider that SMZL developed because of chronic inflammation resulting from a nontuberculous mycobacterial infection.

Pulmonary extranodal marginal zone B-cell lymphoma of mucosa-associated lymph tissue: A case report and literature review.

Extranodal marginal zone B-cell lymphoma of mucosa-associated lymph tissue (MALT lymphoma) is a rare subtype of marginal zone B-cell lymphoma. Most primary MALT lymphoma occurs in the stomach, while lung is an uncommon site of MALT lymphoma. We herein report a case of MALT lymphoma in a 44-year-old female who underwent a pulmonary lobectomy and received rituximab plus CHOP chemotherapy regimen. The patient had an uneventful postoperative course and a good prognosis without tumor recurrence for 3 years.

Clinical characteristics of primary gastric lymphoma detected during screening for gastric cancer in Korea.

BACKGROUND AND AIM: The role of screening endoscopy in primary gastric lymphoma (PGL) has not been investigated. This study aimed to evaluate the clinical characteristics and outcomes of PGLs detected by screening endoscopy in the high prevalence area of Helicobacter pylori (H. pylori) infection. METHODS: This retrospective cohort study enrolled consecutive subjects who were diagnosed with PGL by endoscopic screening in Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Korea, between October 2003 and September 2013. The characteristics and outcome of screening-detected patients (screening group) were compared with consecutive subjects diagnosed with PGL in the outpatient clinic (outpatient group). RESULTS: Of the 105 194 recipients of screening upper endoscopy, 52 (0.049%) were found to have PGL. The median age was 54.2 years (range 23-79), and 65.4% were women. The proportion of PGL to gastric malignancy was 12.1% (52/429) overall, but >30% (25/73) in middle-aged (40-59) women. PGLs in the screening group were more likely to be mucosa-associated lymphoid tissue lymphoma (98.1% vs 60.0%, P < 0.001) and treated with H. pylori eradication alone (90.0% vs 48.1%, P < 0.001) than those in the outpatient group. Moreover, the screening group showed better 5-year overall survival (100.0% vs 89.3%, P = 0.016) and progression-free survival (94.9% vs 83.4%, P = 0.040) than the outpatient group. CONCLUSIONS: In Korea, a high prevalence area of H. pylori infection, PGL seems more prevalent than in Western countries. Endoscopic screening may help to detect early stage H. pylori-positive mucosa-associated lymphoid tissue lymphoma. A high index of suspicion is needed, especially in middle-aged women.

Management of Suspicious Mucosa-Associated Lymphoid Tissue Lymphoma in Gastric Biopsy Specimens Obtained during Screening Endoscopy.

It is often difficult to differentiate gastric mucosa-associated lymphoid tissue (MALT) lymphoma from Helicobacter pylori-associated follicular gastritis, and thus, it becomes unclear how to manage these diseases. This study aimed to explore the management strategy for and the long-term outcomes of suspicious gastric MALT lymphoma detected by forceps biopsy during screening upper endoscopy. Between October 2003 and May 2013, consecutive subjects who were diagnosed with suspicious gastric MALT lymphomas by screening endoscopy in a health checkup program in Korea were retrospectively enrolled. Suspicious MALT lymphoma was defined as a Wotherspoon score of 3 or 4 upon pathological evaluation of the biopsy specimen. Of 105,164 subjects who underwent screening endoscopies, 49 patients with suspicious MALT lymphomas who underwent subsequent endoscopy were enrolled. Eight patients received a subsequent endoscopy without H. pylori eradication (subsequent endoscopy only group), and 41 patients received H. pylori eradication first followed by endoscopy (eradication first group). MALT lymphoma development was significantly lower in the eradication first group (2/41, 4.9%) than in the subsequent endoscopy only group (3/8, 37.5%, P = 0.026). Notably, among 35 patients with successful H. pylori eradication, there was only one MALT lymphoma patient (2.9%) in whom complete remission was achieved, and there was no recurrence during a median 45 months of endoscopic follow-up. H. pylori eradication with subsequent endoscopy would be a practical management option for suspicious MALT lymphoma detected in a forceps biopsy specimen obtained during screening upper endoscopy.

IgG4-producing lymphoma arising in a patient with IgG4-related disease.

We herein report a case in which an IgG4-producing lymphoma arose in a patient with a previous diagnosis consistent with an IgG4-related disease. A 43-year-old man presented with enlarged cervical lymph nodes and was treated with steroids and radiation for what was initially assumed to be Kimura's disease, although the lesions were later histologically re-diagnosed as IgG4-related lymphadenopathy. Fourteen years later, when the patient was 58-years-old, he presented with retroperitoneal fibrosis and swollen lymph nodes. The suspicious lesions were not histologically examined as the patient did not give consent. However, the serum IgG4 concentration was high (1400 mg/dL) and he was clinically diagnosed with systemic IgG4-related disease. Although steroid administration reduced the size of the lesions, tapering the dose finally resulted in systemic, prominently enlarged lymph nodes. Analysis of the biopsy specimen revealed that these multiple lymph node lesions were marginal zone B cell lymphomas that themselves expressed IgG4. Complete remission was achieved after a total of six courses of chemotherapy including rituximab. This case suggests that the infiltrating IgG4-expressing cells observed in IgG4-related disease can clonally expand to malignant lymphomas.

[Follicular and mantle cell lymphoma diagnosed in biopsies of gastroenterocolic region]. / Folikulový lymfóm a lymfóm z plástových buniek v biopsiách orgánov zalúdocno-crevnej oblasti.

The authors present a retrospective analysis of follicular lymphomas (FL) and mantle cell lymphomas (MCL) diagnosed according to the WHO classification (2008) in consecutive biopsies of GI organs in a period of 11 years. The series includes 18 patients with FL verified in 22 biopsies and 44 patients with MCL diagnosed in 54 biopsies. FL represented always a solitary tumor, most often - up to ¾ of all the cases - of a small intestine, more often in its jejunoileal than duodenal parts. The biopsies were obtained almost equally by endoscopical approach, they were usually mucosal and rarely polypectomic, as well as by surgical resections (54,5 % and 45,5 % of the cases respectively). FL of grade 3 was identified in approximately 11 % of the cases, while majority of the patients showed FL of grade 1 or 2. Only 2 patients with duodenal FL relapsed and bioptically verified recidives did not show signs of a high grade transformation. Although it was difficult to identify a nodular growth pattern in more common small biopsies, a typical histomorphology and phenotype mostly allowed the FL diagnosis in the majority of the cases. The FL diagnosis had to be supported by detection of BCL2 translocation only in one case. MCL appeared most often in the stomach and large intestine, the small intestinal cases represented less than 23 %. In » of the patients the lymphoma was multifocal and manifested as lymphomatoid polyposis affecting most often both large and small intestine. In a majority of the MCL patients, the diagnosis was done in mucosal and polypectomic endoscopic biopsies, surgical intervention and resection was recorded in less than 10 % of the cases. Most of the patients showed conventional "centrocytic" MCL morphology and approximately » of the cases showed blastoid MCL. The rebiopsies of 9 patients revealed a relaps of the disease which was locoidentical in 5 of them; in other 4 patients the biopsies documented a dissemination to other GI organs. The blastic transformation was recognized only in one of the relapsing patients. In contrast to FL, in 18 % of the biopsies the MCL diagnosis required a CCND1 gene rearrangement detection by FISH. In summary both of the studied GI lymphomas showed different and heterogenous incidence, clinical manifestation and necessity to support the biopsy diagnosis also by FISH examination. The correct FL and MCL diagnosis represents a conditio sine qua non for an indication of different therapeutical modalities as well as for the prognostic stratification of the patients.

Role of 18F-FDG-PET/CT in the management of marginal zone B cell lymphoma.

The use of PET in patients with marginal zone B cell lymphoma (MZL) is controversial because of variability of fluorodeoxyglucose (FDG) avidity. We analyzed 40 PET/CT in 25 consecutive patients to compare its performance with CT at staging and as a first-line response assessment. Sensitivity of PET/CT and CT was 96 and 76%. Mean standard uptake value was 6.1, 6.9 and 3.4 (p = 0.3) in nodal, extranodal and splenic subtypes, respectively. Of 17 patients (extranodal: n = 9; nodal: n = 6; splenic subtype: n = 2) with both imaging tests available at diagnosis, 8 (47%) had more involved areas with PET/CT than with CT, 75% of which were extranodal lesions. PET/CT resulted in upstaging of five patients although treatment of only two of them was changed. Responses of 15 patients with post-treatment PET/CT were the following: 9 negative and 6 positive of which 3 were isolated residual lesions. Progression was documented in two of these three patients. Response was also assessed by CT in 11 patients. Discrepancies were found in three: Two were in complete remission by CT while PET/CT detected localized residual disease; another patient was in partial remission by CT, whereas PET/CT showed only one positive lesion. Two of these three patients relapsed. Patients with negative post-treatment PET/CT did not relapse. With a median follow-up of 50 months (10-152 months), 3-year overall survival was 100 and 80% for patients with negative and positive post-treatment PET/CT (p = 0.2). Three-year disease-free survival was 86%; the negative predictive value (NPV) was 100%, and the positive predictive value (PPV) was 83.3%. Although a larger number of patients will be required to further confirm these data, we can conclude that PET/CT is a useful imaging tool for both staging and response assessment in patients with nodal and extranodal MZL as a result of its high sensitivity, NPV and PPV.

Clinical activity of everolimus in relapsed/refractory marginal zone B-cell lymphomas: results of a phase II study of the International Extranodal Lymphoma Study Group.

The International Extranodal Lymphoma Study Group coordinated a phase II trial to evaluate the activity and safety of everolimus in marginal zone lymphomas (MZLs). Thirty patients with relapsed/refractory MZLs received everolimus for six cycles or until dose-limiting toxicity or progression. Median age was 71 years (range, 51-88 years). Twenty patients had extranodal, six splenic, four nodal MZL. Twenty-four patients had stage III-IV. Median number of prior therapies was two (range 1-5). Seventeen patients had early treatment discontinuation, in most cases due to toxicity. Median number of cycles was 4.5 (range, 1-16). Among the 24 assessable patients, the overall response rate (ORR) was 25% (95% confidence interval: 10-47). Grade 3-4 adverse events were neutropenia and thrombocytopenia (17% of patients, each), infections (17%), mucositis and odontogenic infections (13%) and lung toxicity (3%). The median response duration was 6.8 months (range, 1.4-11.1+). After a median follow-up of 14.5 months, five deaths were reported: four deaths were due to lymphoma, one was due to toxicity. In an intent-to-treat analysis, the projected median progression-free survival was 14 months. The moderate antitumour activity of everolimus in relapsed/refractory MZLs and the observed toxicity limit its therapeutical applicability in these indolent entities. Lower doses of the drug and, perhaps, different strategies including combination with additional agents need to be explored.

Treatment of gastric marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue with rituximab, cyclophosphamide, vincristine and prednisone.

There is no standard treatment for patients with gastric marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) who are resistant to, or ineligible for, anti-Helicobacter pylori (anti-HP) therapy. In this study, we investigated the activity of the rituximab, cyclophosphamide, vincristine and prednisone (R-CVP) regimen in patients with gastric MALT lymphoma. Patients were included provided they had untreated gastric MALT lymphoma (except for anti-HP therapy) and were resistant to, or ineligible for, anti-HP therapy. Treatment plan consisted of six to eight 21-day cycles of the R-CVP chemotherapy regimen. Toxicity, response, relapse and survival were evaluated. Twenty patients (12 women and 8 men) were included in the analyses with median age of 59 years. Thirteen patients (65%) had stage I tumours, and seven patients (35%) had stages II-IV tumours. The overall response rate was 100%, with 19 (95%) complete responses and one (5%) partial response. Regimen toxicity was mild and mainly hematological, and no cases of gastric bleeding or perforation occurred. After a median follow-up of 56.3 months, three patients had relapsed, and 19 patients remained alive (specific lymphoma survival 100%), of whom 17 had no evidence of disease. In our experience, the R-CVP regimen is a well-tolerated and effective treatment for patients with gastric MALT lymphoma who are resistant to, or ineligible for, anti-HP therapy.

Treatment of indolent primary cutaneous B-cell lymphomas with subcutaneous interferon-alfa.

BACKGROUND: Interferon-alfa is used in the treatment of primary cutaneous B-cell lymphoma (PCBCL). Therapy with interferon-alfa has thus far been reported solely in case reports and small case series, mostly describing intralesional use. OBJECTIVE: We sought to evaluate efficacy, response rate, time to response, duration of response, and safety of subcutaneously administered interferon-alfa for the treatment of cutaneous B-cell lymphoma. METHODS: We conducted a retrospective chart analysis of patients given the diagnosis of PCBCL and treated with interferon-alfa subcutaneously at a tertiary referral center. RESULTS: Fifteen patients with indolent subtypes of PCBCL were identified. The overall response rate was 66.7%; all responding patients went into complete remission. Response was not significantly associated with the maximum tolerated dose. Within the median follow-up time of 40 months, 90% of the responders experienced a relapse; median duration of response was 15.5 months. Adverse events were predominantly mild and in no case led to cessation of therapy. LIMITATIONS: Retrospective nature of the analysis and small number of patients because of scarcity of the disease are limitations. CONCLUSION: Treatment of indolent PCBCL with subcutaneously injected interferon-alfa demonstrated good response rates and tolerability. Response was not dose dependent. Relapses were observed in nearly all responding patients raising the question of interferon-alfa maintenance therapy in PCBCL.