Subclonal TP53 mutations are frequent and predict resistance to radioimmunotherapy in follicular lymphoma

Although TP53 is commonly mutated in transformed follicular lymphoma, mutations are reported in <5% of pretreatment follicular lymphoma (FL) specimens. We assayed archival follicular B-cell non-Hodgkin lymphoma specimens from a completed clinical trial, Southwest Oncology Group S0016, a phase 3 randomized intergroup trial of CHOP (cyclophosphamide, hydroxydaunorubicin, oncovin, and prednisone) chemotherapy plus R-CHOP (rituximab-CHOP) compared with CHOP chemotherapy plus 131-iodine tositumomab (radioimmunotherapy [RIT]-CHOP). Subclonal TP53 mutations (median allele frequency 0.02) were found in 25% of diagnostic FL specimens and in 27% of a separate validation cohort. In the R-CHOP arm, pathogenic TP53 mutations were not associated with progression-free survival (PFS) (10-year PFS 43% vs 44%). In contrast, among patients with no detectable pathogenic TP53 mutation, RIT-CHOP was associated with a longer PFS than with R-CHOP (10-year PFS 67% vs 44%; hazard ratio = 0.49; P = .008). No relationship was detected between PFS and the extent of activation-induced cytidine deaminase (AICDA)-mediated heterogeneity. In summary, subclonal TP53 mutations are common in FL and are a distinct phenomenon from AICDA-mediated genetic heterogeneity. The absence of a detectable subclonal mutation in TP53 defined a population that particularly benefited from RIT.

Orthogonal SARS-CoV-2 Serological Assays Enable Surveillance of Low-Prevalence Communities and Reveal Durable Humoral Immunity

We conducted a serological study to define correlates of immunity against SARS-CoV-2. Compared to those with mild coronavirus disease 2019 (COVID-19) cases, individuals with severe disease exhibited elevated virus-neutralizing titers and antibodies against the nucleocapsid (N) and the receptor binding domain (RBD) of the spike protein. Age and sex played lesser roles. All cases, including asymptomatic individuals, seroconverted by 2 weeks after PCR confirmation. Spike RBD and S2 and neutralizing antibodies remained detectable through 5-7 months after onset, whereas α-N titers diminished. Testing 5,882 members of the local community revealed only 1 sample with seroreactivity to both RBD and S2 that lacked neutralizing antibodies. This fidelity could not be achieved with either RBD or S2 alone. Thus, inclusion of multiple independent assays improved the accuracy of antibody tests in low-seroprevalence communities and revealed differences in antibody kinetics depending on the antigen. We conclude that neutralizing antibodies are stably produced for at least 5-7 months after SARS-CoV-2 infection.

Detection, prevalence, and duration of humoral responses to SARS-CoV-2 under conditions of limited population exposure

We conducted an extensive serological study to quantify population-level exposure and define correlates of immunity against SARS-CoV-2. We found that relative to mild COVID-19 cases, individuals with severe disease exhibited elevated authentic virus-neutralizing titers and antibody levels against nucleocapsid (N) and the receptor binding domain (RBD) and the S2 region of spike protein. Unlike disease severity, age and sex played lesser roles in serological responses. All cases, including asymptomatic individuals, seroconverted by 2 weeks post-PCR confirmation. RBD- and S2-specific and neutralizing antibody titers remained elevated and stable for at least 2-3 months post-onset, whereas those against N were more variable with rapid declines in many samples. Testing of 5882 self-recruited members of the local community demonstrated that 1.24% of individuals showed antibody reactivity to RBD. However, 18% (13/73) of these putative seropositive samples failed to neutralize authentic SARS-CoV-2 virus. Each of the neutralizing, but only 1 of the non-neutralizing samples, also displayed potent reactivity to S2. Thus, inclusion of multiple independent assays markedly improved the accuracy of antibody tests in low seroprevalence communities and revealed differences in antibody kinetics depending on the viral antigen. In contrast to other reports, we conclude that immunity is durable for at least several months after SARS-CoV-2 infection.

Continued Excellent Outcomes in Previously Untreated Patients With Follicular Lymphoma After Treatment With CHOP Plus Rituximab or CHOP Plus 131I-Tositumomab: Long-Term Follow-Up of Phase III Randomized Study SWOG-S0016

Purpose SWOG S0016 was a phase III randomized study that compared the safety and efficacy of R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) with CHOP-RIT (CHOP followed by consolidation with iodine-133-tositumomab radioimmunotherapy) for previously untreated patients with follicular lymphoma. Understanding the long-term outcome of patients provides a benchmark for novel treatment regimens for FL. Patients and Methods Between 2001 and 2008, 531 previously untreated patients with FL were randomly assigned to receive either six cycles of R-CHOP or six cycles of CHOP-RIT. Patients with advanced-stage disease (bulky stage II, III, or IV) of any pathologic grade (1, 2, or 3) were eligible. Results After a median follow-up of 10.3 years, 10-year estimates of progression-free and overall survival were 49% and 78% among all patients, respectively. Patients in the CHOP-RIT arm had significantly better 10-year progression-free survival compared with patients in the R-CHOP arm (56% v 42%; P = .01), but 10-year overall survival was not different between the two arms (75% v 81%; P = .13). There was no significant difference between the CHOP-RIT and R-CHOP arms in regard to incidence of second malignancies (15.1% v 16.1%; P = .81) or myelodysplastic syndrome or acute myeloid leukemia (4.9% v 1.8%; P = .058). The estimated 10-year cumulative incidences of death resulting from second malignancies were not different (7.1% v 3.2%; P = .16), but cumulative incidence of death resulting from myelodysplastic syndrome or acute myeloid leukemia was higher in the CHOP-RIT arm compared with the R-CHOP arm (4% v 0.9%; P = .02). Conclusion Given these outstanding outcomes, immunochemotherapy should remain the standard induction approach for patients with high-risk FL until long-term follow-up of alternative approaches demonstrates superiority.

Abstract 4057: Inhibition of polyploidy and senescence induces intrinsic apoptosis in double hit or double expresser DLBCL

Introduction: Double Hit (DH) or Double Expresser (DE) DLBCL are aggressive Non-Hodgkin’s Lymphomas (NHLs) with translocation or over-expression of MYC and BCL-2 which are incurable with current therapies. MYC is a critical driver of oncogenic phenotypes and regulates expression of numerous genes including aurora kinases (AKs), which are validated drug targets. AKs are over-expressed in DLBCL and AK inhibition in two Phase-II trials of relapsed and refractory B/T-NHL resulted in 20%-30% overall response rate. Bruton’s tyrosine kinase (BTK) plays a central role in B-cell receptor (BCR) signaling and inhibitors of BTK have shown efficacy in B-NHL clinical trials. Targeting CD20 (rituximab) in DLBCL inhibits BCL-2 and induces apoptosis via caspase-3 activation. We hypothesized that DH/DE-DLBCL are amenable to a novel therapeutic strategy of AK, BTK and CD20 inhibition.

Methods: Four DH/DE DLBCL cell lines were evaluated for viability by MTS; polyploidy, senescence and apoptosis by flow cytometry; DNA damage by TUNEL assay. Phospho-BCL-2, -AK and -BTK analysis by western. Safety and efficacy of drug combinations in a mouse xenograft model. Analysis of patient samples and mouse tumors by IHC.

Results: DH/DE-DLBCL cell lines and patient samples displayed over-expression of MYC, BCL-2, BTK and AK-A proteins. Cell viability assays with alisertib alone showed ~30% cell death, while majority of remaining ~70% cells were polyploid and senescent at day-4 (a mechanism of treatment failure). These polyploid and senescent cells (PASC) showed increased levels of phospho-BTK indicating increased BCR signaling (a rationale for combination therapy). We show that alisertib + ibrutinib + rituximab significantly reduced PASCs leading to intrinsic cell death compared to single/double combinations. Dual inhibition of AK + BTK reduced phospho-ERK-1/2, -Bcl-6 and -MYC with increased DNA breaks indicated by up regulation of phospho-H2A-X, -Chk-2, and pro-apoptotic Noxa and Puma proteins. Triple therapy reduced Bcl-2, Bcl-xL and increased Noxa and Puma compromising the mitochondrial outer membrane potential, release of Cyt-C, activation of caspase-3 and induction apoptosis by PARP cleavage. A DLBCL SCID mouse xenograft model showed ibrutinib alone is inactive while alisertib + ibrutinib was additive with a tumor growth inhibition (TGI) rate of ~25%. TGI for ibrutinib + rituximab was ~50-60%. However, triple therapy showed a TGI of &gt;90% and was well tolerated. Survival analysis: 67% of mice alive at day-89 with triple therapy versus 20% with ibrutinib + rituximab. Other treatments showed no survival past day-52.

Conclusions: A novel triple therapy consisting of alisertib + ibrutinib + rituximab inhibits PASCs induced by AK inhibition in DH/DE-DLBCL leading to a significant anti-proliferative signal and intrinsic apoptosis. Our work provides a rationale for exploring these combinations in the clinic.

Citation Format: Shariful Islam, Wenqing Qi, Carla Morales, Laurence Cooke, Catherine M. Spier, Daruka Mahadevan. Inhibition of polyploidy and senescence induces intrinsic apoptosis in double hit or double expresser DLBCL [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4057. doi:10.1158/1538-7445.AM2017-4057

Prediction of Outcome in Diffuse Large Cell Lymphoma by the Major Histocompatibility Complex Class II (HLA-DR, DP, DQ) and Class I (HLA-A, B, C) Phenotype

Ninety-nine consecutive diffuse large cell lymphoma (DLCL) patients were studied by immunohistochemistry to determine whether clinical outcome was predicted by major histocompatibility complex (MHC) antigen phenotypic expression. Statistically significantly shorter disease free survival (p = 0.005), but not overall survival (p = 0.47), was observed when patient lymphomas failed to express class I MHC antigens. We also observed significantly reduced survival of class II MHC HLA-DP negative patients (p = 0.038). This extends our previous finding of poor outcome with absent class II MHC HLA-DR in DLCL(1) to other MHC antigens and demonstrates that the phenomenon of defective class II antigen expression comprises 16% of these DLCL patients. Known clinical parameters predictive of prognosis were equally distributed between phenotypic groups. These findings indicate that aberrancy of immune phenotype in DLCL is critical to patient outcome and we speculate that loss of MHC expression may confound host immunosurveillance and tumor containment.

Genetic polymorphisms in oxidative stress-related genes are associated with outcomes following treatment for aggressive B-cell non-Hodgkin lymphoma

Variable survival outcomes are seen following treatment for aggressive non-Hodgkin lymphoma (NHL). This study examined whether outcomes for aggressive B-cell NHL are associated with single nucleotide polymorphisms (SNPs) in oxidative stress-related genes, which can alter drug metabolism and immune responses. Genotypes for 53 SNPs in 29 genes were determined for 337 patients given anthracycline-based therapies. Their associations with progression-free survival (PFS) and overall survival (OS) were estimated by Cox proportional hazard regression; associations with hematologic toxicity were estimated by logistic regression. To validate the findings, the top three SNPs were tested in an independent cohort of 572 DLBCL patients. The top SNPs associated with PFS in the discovery cohort were the rare homozygotes for MPO rs2243828 (hazard ratio [HR] = 1.87, 95% confidence interval [CI] = 1.14-3.06, P = 0.013), AKR1C3 rs10508293 (HR = 2.09, 95% CI = 1.28-3.41, P = 0.0032) and NCF4 rs1883112 (HR = 0.66, 95% CI = 0.43-1.02, P = 0.06). The association of the NCF4 SNP with PFS was replicated in the validation dataset (HR = 0.66, 95% CI = 0.44-1.01, P = 0.05) and the meta-analysis was significant (HR = 0.66, 95% CI = 0.49-0.89, P < 0.01). The association of the MPO SNP was attenuated in the validation dataset, while the meta-analysis remained significant (HR = 1.64, 95% CI = 1.12-2.41). These two SNPs showed similar trends with OS in the meta-analysis (for NCF4, HR = 0.72, 95% CI = 0.51-1.02, P = 0.07 and for MPO, HR = 2.06, 95% CI = 1.36-3.12, P < 0.01). In addition, patients with the rare homozygote of the NCF4 SNP had an increased risk of hematologic toxicity. We concluded that genetic variations in NCF4 may contribute to treatment outcomes for patients with aggressive NHL.

Phase 2 trial of combined cisplatin, etoposide, gemcitabine, and methylprednisolone (PEGS) in peripheral T-cell non-Hodgkin lymphoma: Southwest Oncology Group Study S0350

BACKGROUND

Patients with peripheral T-cell lymphomas (PTCLs) have inferior progression-free survival (PFS) and overall survival (OS) compared with patients who have aggressive B-cell non-Hodgkin lymphoma. Because PTCLs over express multidrug resistance gene 1/P-glycoprotein (MDR-1/P-gp), we devised platinum, etoposide, gemcitabine, and methylprednisolone (PEGS) with agents that are not substrates of the efflux pump. Gemcitabine was included because of its excellent single-agent activity in PTCL.

METHODS

Patients who had PTCL with stage II bulky disease, stage III or IV disease with extra-nodal, nodal, and transformed cutaneous presentations were eligible. Patients received intravenous cisplatin 25 mg/m(2) on days 1 through 4, etoposide 40 mg/m(2) on days 1 through 4, gemcitabine 1000 mg/m(2) on day 1, and methylprednisolone 250 mg on days 1 through 4 of a 21-day cycle for 6 cycles.

RESULTS

In total, 34 patients were enrolled, 33 were eligible, and 79% were newly diagnosed. Histologic types were PTCL not otherwise specified (n = 15), anaplastic lymphoma kinase (ALK)-negative anaplastic large cell lymphoma (n = 4), angioimmunoblastic T-cell lymphoma (n = 6), or other T-cell non-Hodgkin lymphomas (n = 8). Adverse events included 1 grade 5 infection with grade 3 or 4 neutropenia and 9 grade 4 hematologic toxicities. The overall response rate was 39% (47% in PTCL not otherwise specified, 33% in angioimmunoblastic T-cell lymphoma, 25% in ALK-negative and 38% in other T-cell non-Hodgkin lymphomas). The PFS rate at 2 years was 12% (95% confidence interval, 0.1%-31%), and the median PFS was 7 months. The OS rate at 2 years was 30% (95% confidence interval, 8%-54%), and the median OS was 17 months. Immunohistochemical analysis of P-gp expression revealed strong positivity in a subset of lymphoma cells (n = 6) and tumor endothelium (n = 25).

CONCLUSIONS

Overall, PEGS was well tolerated, but OS was not considered promising given the design-specified targets. These results may serve as a benchmark for future comparisons for non-CHOP regimens.

A phase III randomized intergroup trial (S0016) comparing CHOP plus rituximab with CHOP plus iodine-131-tositumomab for front-line treatment of follicular lymphoma: Results of subset analyses and a comparison of prognostic models

8001

Background: Advanced follicular lymphomas (FL) are considered incurable with chemotherapy and there is no consensus on the best treatment. Outcomes are variable, but can be partially predicted by defined prognostic factors. SWOG and CALGB compared the safety and efficacy of 2 immunochemotherapy regimens in a Phase III trial enrolling 554 patients between 3/1/2001 and 9/15/2008. Methods: Patients were eligible if they had bulky stage II, III or IV FL and had not received prior therapy. Patients randomized to CHOP-R received 6 cycles of CHOP every 21 days + 6 doses of rituximab. Patients randomized to CHOP-RIT received 6 cycles of CHOP, followed by consolidative radioimmunotherapy with tositumomab/iodine I-131 tositumomab. A Cox proportional hazards multi-variable regression analysis assessed the prognostic impact of age, stage, LDH, LN size and number, performance status, hemoglobin, β2 microglobulin, BM involvement, and B symptoms.  The prognostic value of 3 multi-variable models were compared. Results: Outcomes were outstanding with either CHOP-R or CHOP-RIT (2 yr PFS: 76% vs 80% [ p =0.11]; 2 yr OS: 97% vs 93% [p =0.08], respectively).  Subset analyses so far have not identified any subgroups clearly benefitting to a greater degree from CHOP-R or CHOP-RIT in terms of both PFS and OS. Cox multivariable regression analysis identified serum-β2M, LDH level, and FLIPI index as the strongest prognostic factors associated with worse PFS and OS. Conclusions: Both regimens produced outstanding PFS and OS, and no statistically significant differences between them were observed.  FLIPI, FLIPI2, and LDH + β2M models were all strong predictors of patient outcomes.  A combination of LDH + β2M was as good as the FLIPI index, and was simpler to apply.  (Supported in part by NCI grants CA32102 and CA38926 from the NCI and GlaxoSmithKline.) [Table: see text]

Phase II Study of Rituximab Plus Three Cycles of CHOP and Involved-Field Radiotherapy for Patients With Limited-Stage Aggressive B-Cell Lymphoma: Southwest Oncology Group Study 0014

Purpose

To evaluate the effect of rituximab in limited-stage diffuse large B-cell lymphoma (DLBCL), we conducted a multicenter phase II trial combining rituximab with three cycles of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone; R-CHOP) followed by involved-field radiation therapy (IFRT).

Patients and Methods

Southwest Oncology Group (SWOG) study S0014 enrolled patients with newly diagnosed, aggressive, CD20-expressing non-Hodgkin's lymphoma (NHL). Patients had limited-stage disease and at least one adverse risk factor as defined by the stage-modified International Prognostic Index (nonbulky stage II disease, age > 60 years, WHO performance status of 2, or elevated serum lactate dehydrogenase). Four doses of rituximab were infused on days −7, 1, 22, and 43, and CHOP was administered on days 3, 24, and 45, followed 3 weeks later by 40 to 46 Gy of IFRT.

Results

Sixty patients with aggressive NHL were eligible. With the median follow-up of 5.3 years, treatment resulted in a progression-free survival (PFS) of 93% at 2 years and 88% at 4 years. Overall survival (OS) was 95% at 2 years and 92% at 4 years. These results were compared with those from a historic group of patients treated without rituximab on S8736, demonstrating PFS of 78% and OS of 88% at 4 years.

Conclusion

In limited-stage DLBCL, the addition of rituximab to three cycles of CHOP plus IFRT met prespecified study criteria of efficacy, with 2-year PFS of at least 84%, meriting further investigation. There is a pattern of continuing relapse with modest survival gains. We hypothesize that such a pattern may be the result of biologic differences between limited- and advanced-stage lymphoma.

Diffuse Aggressive Histologies of Non-Hodgkin Lymphoma: Treatment and Biology of Limited Disease

A quarter century has passed since the paradigm for treating aggressive histologies of non-Hodgkin lymphoma (NHL) presenting with limited extent of disease (LD) changed from using aggressive surgical staging techniques followed by primary radiotherapy (RT) to clinical staging followed by initial treatment with doxorubicin-containing chemotherapy (CT). This paradigm shift occurred for two reasons. First, unlike the predictable contiguous spread of Hodgkin lymphoma from one lymph node region to the next, the NHLs are largely systemic diseases characterized by early hematogenous spread. Second, the discovery of a potential curative combination of drugs, including cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), for use in advanced disease could eradicate micro-metastatic disease in patients with LD. The focus of current investigation on controlling the systemic nature of the disease has not changed. In this regard, new effective systemic therapies using combination chemotherapy plus monoclonal antibodies have resulted in improved outcome for patients with advanced disease and those treatment strategies are now under investigation in patients with LD.

Loss of MHC class II gene and protein expression in diffuse large B-cell lymphoma is related to decreased tumor immunosurveillance and poor patient survival regardless of other prognostic factors: a follow-up study from the Leukemia and Lymphoma Molecular Profiling Project

The Leukemia and Lymphoma Molecular Profiling Project recently published results from DNA microarray analyses of 240 diffuse large B-cell lymphomas (DLBCLs). Four gene expression "signatures" were identified as correlated with patient outcome, including the major histocompatibility complex (MHC) class II genes (eg, HLA-DRA) which correlated with better survival. We further analyzed the effects of HLA-DRA on survival and correlated gene expression with protein status and tumor-infiltrating lymphocytes. The 5-year overall survival was 24% in the lowest 10% of HLA-DRA expression, 37% in the 10% to 25% group, 50% in the 25% to 50% group, and 55% for patients in the highest 50%. Further analysis demonstrated that the hazard ratio of death was a nonlinear function of HLA-DRA expression. Adjustment for the International Prognostic Index did not alter the impact of HLA-DRA on survival. Other MHC class II genes were found to predict survival similarly. Microarray HLA-DRA expression correlated with the presence or absence of human leukocyte antigen-DR (HLA-DR) protein in 20 of 22 cases assessed. Fewer tumor-infiltrating CD8(+) T cells were detected in MHC class II-negative cases compared with positive cases (2.8% versus 11.0%; P =.001), supporting the hypothesis that loss of tumor immunosurveillance has a devastating effect on patient outcome in DLBCL.

Successful renal transplant outcome after intravenous gamma-globulin treatment of a highly sensitized pediatric recipient

Approximately 10% of patients on the renal transplant (Tx) cadaver waiting list have high (> 20%) panel-reactive antibody (PRA) levels to human leukocyte antigens (HLA). Intravenous gamma-globulin (IVIG) has been shown to reduce anti-HLA cytotoxic antibody levels through an anti-idiotypic antibody-blocking effect. We report a successful renal Tx outcome in a 7-yr-old-girl with high PRA levels owing to a failed renal Tx who experienced a significant reduction in PRA levels (from 96% to 0%) concomitant with IVIG therapy. IVIG was infused weekly (500 mg/kg/week) for 3 consecutive weeks every 12 weeks. Thirty-four months after starting IVIG therapy, the PRA activity dropped to zero and IVIG was stopped. Then IVIG therapy was resumed after 8 months due to a rebound in PRA activity to 52%. Forty-four months after starting IVIG therapy, the patient was cross-matched with a cadaver donor who shared three antigens with the first living donor. The cross-match was positive with the recipient's sera obtained prior to IVIG therapy and negative with the recipient's sera obtained post-IVIG therapy. A successful cadaver renal Tx was performed using anti-thymocyte globulin (ATGAM) induction therapy and a tacrolimus-based immunosuppression protocol. IVIG was given (1 g/kg) prior to Tx and at day 4 post-operatively. A single mild acute rejection episode occurred 10 days post-transplantation that responded to pulse methylprednisolone therapy and an increase in the tacrolimus oral dose. We conclude that a prolonged course of IVIG infusions, without immunosuppressive medications or plasmapheresis, is likely to have been beneficial in modulating the immune response in this highly sensitized recipient. Randomized multicenter trials are required to define the role of IVIG in this specific population.

Chemotherapy alone compared with chemotherapy plus radiotherapy for localized intermediate- and high-grade non-Hodgkin's lymphoma

BACKGROUND

Patients with clinically localized, intermediate- or high-grade non-Hodgkin's lymphoma usually receive initial treatment with a doxorubicin-containing regimen such as cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). Pilot studies suggest that eight cycles of CHOP alone or three cycles of CHOP followed by involved-field radiotherapy are effective in such patients.

METHODS

We compared these two approaches in a prospective, randomized, multi-institutional study. The end points were progression-free survival, overall survival, and life-threatening or fatal toxic effects. Two hundred eligible patients were randomly assigned to receive CHOP plus radiotherapy, and 201 received CHOP alone.

RESULTS

Patients treated with three cycles of CHOP plus radiotherapy had significantly better progression-free survival (P=0.03) and overall survival (P=0.02) than patients treated with CHOP alone. The five-year estimates of progression-free survival for patients receiving CHOP plus radiotherapy and for patients receiving CHOP alone were 77 percent and 64 percent, respectively. The five-year estimates of overall survival for patients receiving CHOP plus radiotherapy and for patients receiving CHOP alone were 82 percent and 72 percent, respectively. The adverse effects included one death in each treatment group. Life-threatening toxic effects of any type were seen in 61 of 200 patients treated with CHOP plus radiotherapy and in 80 of 201 patients treated with CHOP alone (P=0.06). The left ventricular function was decreased in seven patients who received CHOP alone, whereas no cardiac events were recorded in the group receiving CHOP plus radiotherapy (P=0.02).

CONCLUSIONS

Three cycles of CHOP followed by involved-field radiotherapy are superior to eight cycles of CHOP alone for the treatment of localized intermediate- and high-grade non-Hodgkin's lymphoma.

The presence of bcl-1 and bcl-2 gene rearrangements in diffuse small cleaved-cell lymphoma. A disease with diverse molecular and immunophenotypic findings

Clonal rearrangements of the bcl-1 and bcl-2 protooncogenes are found in many B-lineage non-Hodgkin's lymphomas (NHL) and may play a role in their pathogenesis. We investigated rearrangements of the bcl-1 and bcl-2 protooncogenes in 13 cases of B lineage diffuse small cleaved-cell lymphoma (DSCL), and correlated the results with clinical history, immunophenotype, and outcome. Six cases showed bcl-2 rearrangements, including four patients with an antecedent follicular small cleaved-cell lymphoma (FSCL). Two patients had a bcl-1 rearrangement, including one with a previous FSCL. Of the five patients who lacked detectable bcl-1 or bcl-2 rearrangements, one had an FSCL history. Similar to the lack of correlation between clinical history and genotype, there was no correlation between genotype and immunophenotype. Our results indicate that although DSCL is a morphologically uniform disease, different molecular genetic pathways are involved in its genesis. Follow-up showed four of the six DSCL patients with bcl-2 rearrangements were alive with a median survival of 56 months, whereas the median survival of the seven patients lacking a bcl-2 rearrangement was 17 months and included only one survivor. Thus bcl-2 rearrangements in DSCL may define a patient subset with a more indolent genetic abnormality and prolonged survival.

Prognostic significance of the Ki-67-associated proliferative antigen in aggressive non-Hodgkin's lymphomas: a prospective Southwest Oncology Group trial

The growth fraction of tumors from patients with non-Hodgkin's lymphomas (NHL) has been shown to correlate with survival in retrospective studies. The growth fraction can be evaluated using immunohistochemical techniques employing the Ki-67 monoclonal antibody (MoAb) that marks a nuclear protein present in cycling cells. The purpose of this study was to evaluate the clinical utility of the Ki-67 MoAb for predicting survival. Using a prospective trial design in a multi-institutional cooperative trials group, the proliferative index, clinical outcome, and statistical correlations were independently assessed for previously untreated patients with advanced stages of intermediate- and high-grade histologies of NHL treated on Southwest Oncology Group study (SWOG 8516, Intergroup 0067). The proportion of Ki-67-positive cells was determined on snap-frozen thin tissue sections. A proliferative index of 80% or greater, as determined from prior retrospective studies, identified a group of patients (18%) who had a poor outcome. Overall survival was significantly reduced in these patients with a high Ki-67-associated proliferative index compared with those with a low proliferative index (P = .001). One-year survival estimates were 82% (low proliferative index) versus 18% (high proliferative index). A multivariate regression analysis incorporating commonly used clinical prognostic features confirmed the independent effect of proliferation on survival (relative risk estimate 5.9; 95% confidence interval, 2.2, 16.1). The Ki-67 MoAb identifies a group of patients with rapidly fatal NHL for whom currently available chemotherapy is inadequate.

NCAM (CD56)-positive malignant lymphoma

CD56 has been found to identify an isoform of the neural cell adhesion (NCAM). NCAM is a member of the immunoglobulin superfamily of cell adhesion molecules; it is related to a variety of leukocyte antigens and to several cell adhesion molecules believed relevant to malignant behavior in a variety of neoplasms. It contains polysialic acid, which appears to regulate binding avidity of NCAM and other cell adhesion processes. We have identified a group of NCAM-positive lymphomas. Compared to a group of NCAM-negative lymphomas, this group exhibited frequent involvement of unusual sites and a generally aggressive course. Another series of CD56-positive hematolymphoid malignancies has recently been described, from Hong Kong; this group also exhibited involvement of unusual sites and displayed a very aggressive course. Together these series suggest that NCAM on lymphoma is of biological and clinical significance in terms of tumor behavior and spread.

Deficient tumor-infiltrating T-lymphocyte response in malignant lymphoma: relationship to HLA expression and host immunocompetence

Tumor-infiltrating T-lymphocytes (T-TIL) are putative mediators of tumor containment that exhibit unique specificity for autologous tumor cells. The magnitude of T-TIL response in biopsy specimens from patients with B-cell lymphoma has been suggested as an independent predictor of clinical outcome. Since recognition of tumor antigens may occur in association with major histocompatibility complex (MHC) molecules, effective T-TIL tumor immunosurveillance may be limited by either failure to express MHC-encoded recognition structures and/or host T-cell immunocompetence. To further delineate T-cell immunoregulation in B-cell lymphoma, we assessed T-TIL fraction and tumor expression of invariant class I and class II HLA determinants by immunohistochemistry in biopsy specimens. Two distinct clinical cohorts of B-cell lymphoma were investigated to delineate pathogenetic differences in T-TIL response. One group, representing immunodeficient and transplant-related lymphomas, comprised 18 patients with AIDS- or allograft-related lymphoma. The second group comprised 83 consecutive cases of sporadic diffuse large cell (DLCL) lymphoma. Median CD8+ T-TIL was significantly lower (4.9% versus 12.7%) among immunodeficiency-associated lymphoma and the frequency of cases with low (< 6%) CD8+ T-TIL greater (76% versus 23%) (p < 0.0001). None of the immunodeficiency-associated lymphomas demonstrated non-polymorphic HLA loss. Absence of one or more class I or II HLA determinants was found in 13 out of 19 (68%) sporadic DLCL specimens with low CD8+ T-TIL, compared to 20% of cases with higher T-TIL fraction (p = 0.0004). These findings implicate impaired host immunosurveillance in deficient T-TIL response in immunodeficiency-associated B-cell lymphoma, whereas low T-TIL in sporadic cases of DLCL relates to tumor loss of HLA determinants. Strategies to modulate tumor HLA expression or augment antitumor response merit investigation in patients with B-cell lymphoma.

Isolated ocular involvement in non-Hodgkin's lymphoma with immunocytochemical evaluation

We report the case of a patient with isolated ocular involvement and non-Hodgkin's lymphoma (also known as reticulum cell sarcoma). Most non-Hodgkin's central nervous system lymphomas are large cell lymphomas derived from B-cells. The patient initially had iritis OD and vitreous cells OS. Eventually, rubeosis and vitritis developed OD. A systemic workup showed no extraocular lymphoma. Immunocytochemical analysis was done on the vitreous OD and detected a monoclonal B-cell population of large lymphoid cells. This case shows the frequent delay in making the diagnosis of this condition. This diagnosis must be remembered when a patient has vitreous opacities.

P-glycoprotein expression in human plasma cell myeloma: correlation with prior chemotherapy

Multidrug-resistant (MDR) myeloma patients failing chemotherapy may express P-glycoprotein (PGP), which serves as an efflux pump protecting the neoplastic cells. Unknown is whether PGP expression might relate to prior cytotoxic drug exposure. To address this question, we studied 106 consecutive bone marrow samples from 104 myeloma patients with samples studied either before or after therapy and at the time of relapse. We performed an established immunocytochemical assay of PGP using an MDR-1-specific monoclonal antibody and correlated PGP status with prior chemotherapy dosage. Myeloma patients with no prior therapy had a low incidence of PGP expression (6%, 3/47), whereas those receiving chemotherapy had a significantly higher incidence (43%, 21/49) (P < .0001). A substantially higher incidence of PGP expression (50%, 83%, respectively) occurred when the total vincristine dose exceeded 20 mg and when doxorubicin exceeded 340 mg. In the 11 patients who received both high vincristine and doxorubicin dosages (> 20 mg, > 340 mg total dose) there was 100% incidence of PGP expression in the tumor cells. These data provided the basis for a predictive mathematical model from which dose-related PGP expression normograms were generated. Time with myeloma for PGP-negative patients (mean 33 months) had overlapping confidence limits with PGP-positive patients (mean 42 months), suggesting that disease duration was not a significant variable. PGP expression did not correlate with other clinical factors or immunophenotypic factors. Our findings indicate a strong correlation between PGP expression in myeloma and past chemotherapy in myeloma, in particular, related to prior exposure to the natural product agents vincristine and doxorubicin. Additionally, the proportion of PGP-positive plasma cells was significantly higher in the doxorubicin-treated patients than the nondoxorubicin-treated patients (87.7% v 65.17%; P = .013). Combined high vincristine and doxorubicin total dosage appear highly predictive of PGP expression.

Multidrug resistance in acute leukemia: a conserved physiologic function

Native resistance to conventional chemotherapy remains an important cause of treatment failure in the adult acute leukemias. Delineation of cellular mechanisms of drug resistance therefore represents a prerequisite to the development of more effective treatment strategies. The multidrug resistance (MDR) phenotype represents one such mechanism of resistance with direct clinical relevance. This phenotype occurs normally in certain mammalian tissues, and is detectable in tumor cell lines selected for resistance to naturally occurring antineoplastics. The mdr1 gene or its glycoprotein product, P-glycoprotein, is detected with high frequency in secondary acute myeloid leukemia (AML) and poor-risk subsets of acute lymphoblastic leukemia. In prospective studies in AML, MDR overexpression is an independent determinant of response to treatment and overall survival with conventional-dose induction regimens. Investigations of mdr1 regulation in normal hematopoietic elements has shown a pattern which corresponds to its regulation in acute leukemia, explaining the linkage of mdr1 to specific cellular phenotypes. Therapeutic trials are now in progress to test the ability of various MDR-reversal agents to restore chemotherapy sensitivity in high-risk acute leukemias.

Diffuse small cleaved-cell lymphoma: a heterogeneous disease with distinct immunobiologic subsets

PURPOSE AND METHODS

Diffuse small cleaved-cell lymphoma (DSCL) is a relatively uncommon non-hodgkin's lymphoma (NHL) in the United States and has not been the subject of recent in-depth study of factors predictive of outcome. It is unique among the NHL of intermediate grade because there is no evidence of a curable subset of patients. To investigate whether any laboratory data might predict outcome, we studied 33 cases collected during a 12-year period and correlated morphology, immunohistochemistry, and serum lactate dehydrogenase (LDH) with clinical data and outcome.

RESULTS

We found that proliferative rate (Ki-67), cell lineage (T v B cell), and serum LDH were associated with significant differences in survival. A Ki-67 value greater than or equal to 20% was associated with a median survival of 20 months compared with 80 months for lower values (P = .0002); patients with tumors of T-cell lineage had a median survival of 20 months compared with 40 months for those with B-cell neoplasms (P = .0143); and a serum LDH greater than 225 IU/L was associated with a median survival of 8 months compared with 40 months for lower LDH levels (P = .0004). Blastoid morphology was also linked to a trend toward poor outcome (P = .08). Neither a history of low-grade lymphoma nor the presence of residual immunologically detectable follicles influenced outcome (P = .93 and .97, respectively).

CONCLUSION

We conclude that high Ki-67, high LDH, and T-cell lineage each identify DSCL patients with poor outcome.

Neural cell adhesion molecule-positive peripheral T-cell lymphoma: a rare variant with a propensity for unusual sites of involvement

A distinct subset of patients with peripheral T-cell lymphoma (PTCL) is described which reacts with Leu-19 (CD56), an antibody that has been shown to identify the neural cell adhesion molecule (NCAM). These NCAM-positive PTCL patients (11 of a series of 46 PTCL; 24%) exhibited a striking predilection for unusual anatomic sites of involvement: central nervous system (36%), muscle (18%), gastrointestinal tract, and nasopharynx (27% each). Additional extranodal sites of involvement included the pituitary, thyroid, parathyroids, adrenals, and pancreas. The NCAM-positive subset also exhibited a characteristic phenotypic profile, with significantly lower expression of CD3 and CD5 compared with the NCAM-negative group. RNA transcripts consistent with the NCAM gene were detected in tissue samples from five Leu-19-positive cases using a reverse transcriptase-polymerase chain reaction assay, supporting the idea that Leu-19 recognizes NCAM in these patient samples. This suggests that the expression of the NCAM plays a role in the behavior and localization of lymphomas. Because of the unique clinical and phenotypic characteristics of this group it may be designated as "NCAM-positive peripheral T-cell lymphoma."

A multidisciplinary approach to the diagnosis of cutaneous T-cell lymphomas

The cutaneous T-cell lymphomas (CTCLs) comprise a spectrum of non-Hodgkin lymphomas with a predilection for the skin. This heterogeneous group of CTCLs include the prototypic CTCL mycosis fungoides (MF) and the recently described Ki-1+ lymphomas. MF is notoriously difficult to diagnose in its early stages. The histologic appearance of early MF is indistinguishable from that of chronic dermatitis. The limitations of light microscopy in the diagnosis of the CTCLs have led to the development of other diagnostic laboratory techniques. The best approach to the diagnosis of the CTCLs is a multidisciplinary one and should include ultrastructural morphometry, immunophenotyping, immunogenotyping, and histologic evaluation whenever possible. It is the purpose of this overview to point out the strengths and weaknesses of each of these techniques and, together with clinical input, to provide a comprehensive and rational approach to patient care.

Lymphomas of the mediastinum

The purpose of this clinicopathologic overview is to describe the types of lymphomas that present in the mediastinum. A comparison of the frequency of the different subtypes of lymphoma that are found in children and adults is provided. In general, immunohistochemistry and immunophenotyping studies are essential to the laboratory workup of neoplasms presenting in the mediastinum. An assessment of proliferative index in lymphoma is most helpful to determine tumor aggressiveness and patient prognosis. Electron microscopy is most helpful in the differential diagnosis of mediastinal neoplasms, where lymphomas may be distinguished from nonlymphomatous neoplasms using key ultrastructural features. The role of electron microscopy in the subclassification of lymphomas is mostly academic, with a few exceptions. The varied ultrastructural appearance of Hodgkin's cells and of different subtypes of non-Hodgkin's lymphoma is illustrated, using cases from our patient files. An ultrastructural study of lacunar cells in Hodgkin's disease provides evidence that the formation of lacunae may have a structural and/or physiologic basis. Mummified cells showing some of the features of a physiologic form of cell death, called apoptosis, are also described.

Myelodysplastic transformation of polycythemia vera: case report and review of the literature

We report a case of refractory anemia with excess blasts (RAEB) developing in a 67-year old man with a history of polycythemia vera; results of cytogenetic and immunophenotyping studies are described. In this report the clinical, cytogenetic and hematologic features of myelodysplasia complicating polycythemia vera are reviewed. Results of immunophenotyping and cytogenetic studies, and the preponderance of cases developing after myelosuppressive therapy suggest that in the majority of cases myelodysplasia is treatment-related.

Expression of the multidrug resistance gene product (P-glycoprotein) in myelodysplasia is associated with a stem cell phenotype

Previous studies have indicated relative resistance to chemotherapy in the myelodysplastic syndromes (MDS) and associated acute leukaemia. To determine if multidrug resistance may contribute to chemoresistance in these disorders, we studied bone marrow specimens for P-glycoprotein expression (P-GP) by immunocytochemical staining with monoclonal antibodies reactive with cytoplasmic (C219) or surface epitopes (MRK16) of P-GP. Forty-five case specimens from 43 patients were studied, including 32 cases of primary MDS, seven cases of acute myeloid leukaemia (AML) following MDS, and six therapy-related haematological disorders. Cytogenetic analysis was available on 36 specimens. Two staining patterns were detected: (1) cytoplasm and plasma membrane, and (2) staining restricted primarily to the nuclear-cytoplasmic junction. P-GP was detected in seven (22%) cases of primary MDS, four (57%) cases of AML evolving from MDS, and five (83%) cases of therapy-related haematological disorders. Expression of P-GP was restricted to blasts and leukaemic monocytes, and was otherwise absent from terminally differentiated blood cells. Analysis of the relation between P-GP expression and reactivity with the human progenitor cell antigen CD34, revealed a highly significant association (P = 0.001). P-GP reactivity was distributed equally among normal and abnormal karyotypes and did not correlate with specific cytogenetic abnormalities. These findings indicate that multidrug resistance in MDS and karyotypically-related haematological disorders is closely linked to a stem cell phenotype and may contribute to chemoresistance in these disorders.

P-glycoprotein expression in malignant lymphoma and reversal of clinical drug resistance with chemotherapy plus high-dose verapamil

P-glycoprotein is a transmembrane protein thought to function as an efflux pump to detoxify cells. It is associated with multidrug resistance in laboratory systems and has recently been found in human tumors associated with in vitro and clinical drug resistance. We used an immunohistochemical method employing two monoclonal antibodies, JSB-1 and C-219, to detect expression of P-glycoprotein in lymphoma patients. One of 42 newly diagnosed and untreated lymphoma patients (2%) and seven of 11 previously treated and drug-resistant patients (64%) had detectable levels of P-glycoprotein (P less than .001). Based on prior reports suggesting that verapamil sensitizes drug-resistant cancer cells to chemotherapy by competitive inhibition of the P-glycoprotein, we tested the efficacy of verapamil as a chemosensitizer in 18 patients with drug-refractory disease. All patients had previously failed or relapsed within 3 months of a doxorubicin-vincristine-containing drug regimen. Patients received day-1 cyclophosphamide, and 4-day continuous infusion doxorubicin and vincristine and oral dexamethasone (CVAD). CVAD was combined with 5-day continuous infusion verapamil given at maximally tolerated dose. Overall, 13 of 18 patients (72%) responded to treatment including five complete remissions (CRs; 28%). The median duration of response was 200 days and median survival was 242 days. The dose-limiting toxicity of the verapamil infusion was temporary cardiac dysfunction including hypotension, congestive heart failure, and cardiac arrhythmia. We conclude that the P-glycoprotein is uncommonly expressed in untreated lymphomas and frequently expressed in clinically drug-resistant disease, and that chemotherapy using CVAD plus maximally tolerated doses of verapamil results in a high response rate in patients carefully selected for clinical drug resistance.

Immunobiologic factors predictive of clinical outcome in diffuse large-cell lymphoma

The prognostic importance of immunobiologic factors in diffuse large-cell lymphoma (DLCL) is studied in 105 consecutive DLCL patients. Multivariate results using the Cox proportional hazards model clearly indicate that the Ki-67 index (P = .002), a marker of cell proliferation activity, and the presence or absence of human leukocyte antigen-DR (HLA-DR) (P = .007) are strong predictors of survival even in the presence of established clinical factors of stage (P = .015) and symptoms (P = .050). Using these four variables, prognostic groups were formed identifying patient groups with varying degrees of risk. The group of patients with three or four risk factors present at the time of diagnosis had a median survival of 4 months compared with a median survival of 59 months for the group with no risk factors. Similarly, prognostic groups for disease-free survival (DFS) were constructed based on the proportional hazards model that involved B versus T phenotype (P = .035) and HLA-DR (P = .054). Median DFS for the patient group with one or two risk factors present was 11 months compared with 43 months with no risk factors present. This study suggests immunobiologic parameters are important predictors of clinical outcome in DLCL patients and are of value in identifying subgroups of patients who have not responded to currently available therapy. The practical significance of this study is to identify parameters that may suggest specific changes in therapy of patient subgroups.

T-cell antigen-positive multiple myeloma

We report the simultaneous expression of T-cell antigens on the myeloma cells from six patients with multiple myeloma (MM). These six patients come from a total population of 215 samples (115 direct samples, clinical incidence of 5.2%) of plasmacytic malignancies immunotyped at the University of Arizona. Four patients expressed T helper antigen (Leu 3, CD4), one expressed T-cell antigen receptor (Leu 4, CD3), and one expressed E-rosette antigen receptor (Leu 5, CD2). The presenting clinical features, histology, and plasma cell morphology showed no differences from multiple myeloma patients who did not express T-cell antigen. However, although the survival duration ranged from 5 to 93 mo overall, survival from demonstration of T antigen expression was very short, (2 to 7+ mo), with five of six (80%) patients dying less than or equal to 5 mo after study. The reason for T antigen expression is unknown. It may indicate that myeloma can arise from a normally minor subpopulation of B cells involved with immunoregulation; conversely, it could be a coincidental aberrancy associated with malignant change in the plasma cells.

Tumor-infiltrating T-lymphocytes in B-cell diffuse large cell lymphoma related to disease course

Recent data from studies of experimental murine tumors and certain human tumors (primarily melanoma) suggest that tumor-infiltrating T-lymphocytes (T-cell TILs) represent a highly potent and specific host antitumor response. We conducted an immunohistochemical analysis of the T-cell TIL subpopulations in frozen tissue sections taken from 82 consecutive B-cell diffuse large cell lymphoma (DLCL) patients. Initially, we analyzed the relationship in these patients between relapse-free survival (RFS) and their T-cell TIL characteristics. Nineteen patients had a low percentage (less than 6% of Leu-2+ (suppressor/cytotoxic) T-cell TILs, and 63 patients had a high percentage (greater than 6%) of Leu-2+ TILs. We found that a low percentage of Leu-2+ TILs correlated with a reduction in RFS: at 20 mo follow-up, all 19 low Leu-2+ patients had relapsed, whereas 70% of the 63 high Leu-2+ patients remained relapse-free (P = 0.008). No significant correlations appeared between patients' T-cell TIL subsets and overall survival. The percentage of newly diagnosed tumors with low counts of Leu-4+ (pan-T) TILs was marginally greater among interleukin-2 (IL-2) receptor-positive tumors than among IL-2 receptor-negative tumors (50 versus 28%, P = 0.098), which suggests that specific phenotypic characteristics of B-cell DLCL may modulate the host T-cell TIL response. Our results indicate that the host's T-cell TIL response in B-cell DLCL can be quantitated from frozen tissue sections and that this response may be related to disease course. Further related TIL studies may lead to new immunorestorative therapeutic approaches for patients with deficient or aberrant cytotoxic T-lymphocyte host responses.

Myelomonocytic antigen positive multiple myeloma

In a four year span, between 1983 and 1987, 215 bone marrow and cell culture samples from 125 myeloma patients were immunotyped and coexpression of myelomonocytic and plasma cell antigens occurred in 16 (13%). We employed both immunohistochemical and flow cytometry methods including coplots and double labelling. Three types of myeloma cases were found: (1) those with isolated myeloid antigen coexpression, usually Leu M1 or esterase (BE, CE) positive (11 cases); (2) those with multiple myeloid antigens (Leu M1, M3, M5, MY7, BE, CE) (four cases); and (3) one case beginning as 1 and ending as 2. Isolated myeloid antigen expression was generally associated with typical features of myeloma with survival close to the anticipated median (33 months), while multiple myeloid antigen expression was associated with more aggressive disease and shorter survival duration (median survival 16 months). The latter subgroup also had other poor prognostic factors including high labelling index and common acute lymphoblastic leukemia antigen (CALLA) positivity. Other features found overall were frequent abnormal karyotypes (seven of 12 abnormal) and coexpressed IgA (eight of 16); all IgA+ cases also coexpressed Leu M1. We conclude that there is an unusual and unexpected predilection for coexpression of myelomonocytic antigens in myeloma cells. The reasons are not immediately obvious. Whether the coexpression indicates that myeloma cells truly have latent multilineage potential or just aberrantly coexpress other hematopoietic antigens as a manifestation of malignancy remains to be explained. However, a cell line established from the bone marrow of one patient is a valuable scientific tool allowing detailed analysis of these questions.

Nuclear contour irregularity correlates with Leu-9-, Leu-8- cells in benign lymphoid infiltrates of skin. An ultrastructural morphometric and quantitative immunophenotypic analysis suggesting the normal T-cell counterpart to the malignant mycosis fungoides/Sézary cell

The purpose of the present study was to determine if a nonmalignant skin-associated T-cell might exhibit nuclear irregularity and represent the normal counterpart to the malignant Sézary T-cell found in mycosis fungoides (MF) and the Sézary syndrome (SS). Punch skin biopsies from ten benign lymphoid infiltrates of skin were subjected to ultrastructural morphometric analysis and quantitative immunohistochemistry (on serial frozen sections) using a battery of monoclonal antibodies. Form factor (FF) (4 pi A/p2) was used to assess nuclear contour irregularity. The lymphoid infiltrates were morphometrically heterogeneous (range of FF values: 0.482-0.704). Immunophenotypically, there was marked variation in host response to the variety of antigens presented. Linear regression analysis was used to determine if nuclear contour irregularity showed any statistical relationship to immunophenotypically defined lymphocyte subpopulations. It was determined that nuclear contour irregularity (mean FF values) did not correlate with the presence of any surface antigen tested. This included the antigens Leu-2a, Leu-3a + b, Leu-4, Leu-6, Leu-7, Leu-8, Leu-9, Leu-14, and Ia. There was, however, significant correlation of increased nuclear contour irregularity with the presence of Leu-9- and Leu-8- cells (r = 0.7 and 0.6, respectively), lymphocyte subsets reportedly deficient in MF and the SS. This finding leads to the speculation that the Leu-9-, Leu-8- reactive T-cell with an irregular nucleus might represent the normal counterpart to the malignant clonally expanded T-cell found in MF and the SS. It was also determined that helper to suppressor ratios varied 68-fold from 0.2 to 13.5 among these ten benign lymphoid infiltrates of skin. This finding underscores the futility of using helper to suppressor ratios as a diagnostic tool in defining T-cell malignancies.

The aberrancy of immunophenotype and immunoglobulin status as indicators of prognosis in B cell diffuse large cell lymphoma

To assess the prognostic significance of the immunophenotype in diffuse large cell lymphoma (DLCL), 105 DLCL patients were studied between 1978 and 1987 using a panel of 40 monoclonal antibodies applied to frozen tissue. Eighty-three patients were found to have B cell phenotypes, and 20 patients had T cell phenotypes. Focusing on markers relevant to clinical outcome among B cell LCL showed that lack of expression of the pan B antigens Leu14 and Leu16 were correlated with decreased survival (Leu14, P = 0.01; Leu16, P = 0.06; log-rank). HLA-DR activity also showed that lack of expression of this antigen correlated with poor survival (P = 0.004, log-rank). Kappa light chain immunoglobulin lack of expression showed predictive value for decreased survival as well (P = 0.005, log-rank). Multivariate analyses of known clinically important variables and the immune phenotypes confirm that the loss of HLA-DR and B cell aberrancy are independent factors predicting a poor clinical outcome. Losing some B activation/kappa antigens appears to be a broad biologic phenomenon linking surface antigen lack of expression with decreased survival. This suggests that aberrancy of immunophenotype and immunoglobulin status are key predictors of survival in B-LCL.

The prognostic significance of the immunotype in diffuse large-cell lymphoma: a comparative study of the T-cell and B-cell phenotype

The clinical significance of immunophenotyping of the non-Hodgkin's lymphomas is controversial. Therefore, we conducted the present study of 103 consecutively accrued diffuse large-cell lymphoma (DLCL) patients to define, independently of histologic subtypes, the prognostic importance of phenotyping. We used an extensive panel of monoclonal antibodies to T- and B-cell antigens to assign all patients immunologically into the T-cell (20 patients) or B-cell group (83 patients). The only significant differences in pretreatment clinical variables between the two patient groups were the higher frequency of bulky disease (greater than 10 cm) in B-cell patients (P = .008) and more frequent skin involvement in the T-cell group (P less than or equal to .001). Multiagent doxorubicin-containing chemotherapy regimens were employed as initial therapy in over 83% of the patients in each group. Our study revealed that disease-free survival (DFS) was significantly shorter in the T-cell patients than in the B-cell DLCL patients (median DFS, 10.8 months for T-cell and 42.7 months for B-cell; P = .01, log rank). No patient with T-cell DLCL remained disease free for longer than 2 years, whereas 55% of the B-cell group were disease free at 2 years. Univariate and multivariate analyses of all major prognostic factors of DFS suggest that the T-cell phenotype indicates an incurable subset of DLCL patients. Although the B-cell group had a twofold advantage in median survival (35 months v 18 months), actuarial overall survival was not significantly different between the two patient groups (P = .23). Our results indicate the need for new approaches in the search for a curative treatment for T-cell DLCL.

HLA-DR (Ia) immune phenotype predicts outcome for patients with diffuse large cell lymphoma

The clinical utility for establishing the immune phenotype in patients with non-Hodgkin's lymphoma is controversial. To help resolve this dilemma, we studied 104 consecutive patients with diffuse large cell lymphoma, the most common subtype of potentially curable non-Hodgkin's lymphomas. The presence or absence of the human class II histocompatibility antigen was determined using the monoclonal antibody anti-HLA-DR (Ia), and the results correlated with pretreatment clinical features and survival. We found that eight HLA-DR negative patients had similar pretreatment clinical characteristics compared with 96 HLA-DR positive patients, but HLA-DR negative patients had a significantly shorter survival duration compared with HLA-DR positive patients (P = 0.003 log-rank). The median survival of the HLA-DR negative patients was 0.5 years compared to 2.8 yr for the HLA-DR positive patients. No HLA-DR negative patient survived beyond 1.5 yr. A multi-variate analysis, adjusting for prognostic factors of known clinical significance, confirmed the importance of HLA-DR as a prognostic factor (P = 0.016). We conclude that determining the presence of HLA-DR is a relatively simple pretreatment study that identifies a small but important group of patients who are not curable using currently available combination chemotherapy.

Independent prognostic significance of a nuclear proliferation antigen in diffuse large cell lymphomas as determined by the monoclonal antibody Ki-67

To assess the prognostic significance of the growth fraction in diffuse large cell lymphoma (DLCL), we studied 105 DLCL patients with the monoclonal antibody Ki-67 applied to frozen tissue sections. Ki-67 detects a nuclear antigen associated with cell proliferation not found in resting cells. Ki-67 findings and other clinical prognostic factors were correlated with outcome using univariate and multivariate analyses in the proportional hazards model. High proliferative activity, defined as nuclear Ki-67 expression in greater than 60% of malignant cells (Ki-67 greater than 60), was found to be a strong predictor of poor survival among these patients (P = .003, log-rank). The 19 patients with Ki-67 greater than 60% had a median survival of 8 months compared with a median survival of 39 months for the 86 patients with Ki-67 less than or equal to 60%. Examination of pretreatment clinical variables indicated the patient groups were similar with regard to age, sex, stage, B symptoms, tumor bulk, and lactate dehydrogenase (LDH). Both patient groups received comparable curative intent therapy and showed comparable complete response rate precluding treatment differences as modifying outcome. Multivariate analysis indicated Ki-67 is an independent predictor of survival (multivariate P = .006). Further statistical analysis using only B-cell DLCL patients treated with CHOP (63 patients) indicated that Ki-67 greater than 60 retained strong prediction of poor outcome (P = .002, log-rank) among this homogeneous group. We conclude that high proliferative activity (Ki-67 greater than 60) is an independent factor allowing laboratory prediction of probable poor outcome of DLCL.

Clonal ambiguity of human immunodeficiency virus-associated lymphomas. Similarity to posttransplant lymphomas

Initial biopsy specimens from two patients with lymphadenopathy and human immunodeficiency virus antibody-positive serum presented considerable difficulty in making specific histologic and immunologic diagnoses, although subsequent biopsy specimens revealed clear progression to acquired immunodeficiency syndrome (AIDS)-associated lymphomas. The initial biopsy specimens revealed multifocal clusters of large blastic lymphoid cells, with some clusters showing a monoclonal lambda light chain predominance, whereas other clusters showed a kappa predominance, indicating considerable phenotypic ambiguity suggestive of polyclonality. This initial clonal ambiguity was followed within two to three months by overt histologic, phenotypic, and clinical malignant transformation to a diffuse high-grade monoclonal B-cell lymphoma. These data have significant implications for the clonality and pathogenesis of AIDS-associated lymphoproliferative disorders. AIDS-related lymphomas may evolve from an initial multiclonal B-cell expansion similar to that described in other severely immunosuppressed patients (eg, with posttransplantation lymphoma).

Lennert's lymphoma. A clinicopathologic study with emphasis on phenotype and its relationship to survival

In this report we describe the results of a clinical and immunohistochemical analysis of 11 consecutive patients with the specific clinicopathologic entity of Lennert's lymphoma (non-Hodgkin's malignant lymphoma with a multifocal epithelioid histiocytic reaction [MLEH]) evaluated at the Arizona Cancer Center. Detailed immunophenotyping of ten patients showed that seven patients (73%) had an activated "novel" T-cell phenotype, indicative of peripheral T cell lymphoma (PTL). Additionally, six of these seven PTL patients had T-helper (Leu-3) antigen expression to the exclusion of T-suppressor (Leu-2) expression. Three patients, in complete contrast, had a B-cell lymphoma with monoclonal immunoglobulin expression. The B-cell MLEH were morphologically indistinguishable from T-cell MLEH. Clinically, the initial diagnosis proved difficult; ten of the 11 patients were initially misdiagnosed, most often as another lymphoid disorder or as granulomatous disease (mean delay of 10 months in diagnosis from onset of symptoms). The median survival of all patients was 20 months (1 to 45+ months) with two apparent subgroups: those who had rapid progression of disease with a median survival of 5 months, all of T-cell phenotype; and a small group whose median survival has not yet been reached, all of B-cell phenotype. Our results suggest that the immunophenotype, B-cell versus T-cell, may be a major predictor of survival, with B-cell MLEH patients having a longer survival than those of T-cell type.

Lethal midline granuloma with a novel T-cell phenotype as found in peripheral T-cell lymphoma

Lethal midline granuloma (LMG), initially a clinical description, includes an uncommon group of disorders characterized by a relentless, destructive process involving the upper respiratory structures. Its etiology and pathogenesis are uncertain, probably varied, and the distinction between inflammatory and malignant processes is difficult despite extensive clinical and histopathologic evaluation. The need for new techniques for rapid diagnosis has important therapeutic implications. Using an extensive panel of T- and B-cell monoclonal antibodies the authors describe a patient with clinically and pathologically typical LMG demonstrating an "activated" T-cell phenotype with a "novel" pattern characteristic of peripheral T-cell lymphoma, strongly implying that some cases of LMG are more closely related to neoplastic T-cell lymphoproliferative disorders than to inflammatory conditions. Further studies using these immunotyping techniques may help clarify the pathogenesis of LMG, and may uncover specific diagnostic and prognostic phenotypic patterns.

Mantle zone lymphoma with central nervous system involvement

A 68-year-old man with a 7-year history of lymphocytosis and lymphadenopathy is described. Accelerated disease, indicated by bilateral optic nerve and cerebrospinal fluid involvement, prompted thorough histologic and immunologic assessment. Although initially believed to have chronic lymphocytic leukemia (CLL), results showed mantle zone lymphoma (MZL) with central nervous system (CNS) involvement. The authors believe that this represents the first case of MZL with CNS involvement.

Immunophenotypes in "well-differentiated" lymphoproliferative disorders, with emphasis on small lymphocytic lymphoma

The histologic, immunophenotypic, and clinical findings in 24 cases of "well-differentiated" lymphoproliferative disorders are presented, with an emphasis on small lymphocytic lymphoma (SLL; well-differentiated lymphocytic lymphoma, WDLL). SLL was diagnosed in 18 patients, Waldenström's macroglobulinemia in one, mantle zone lymphoma (MZL) in four, and intermediate differentiated lymphocytic lymphoma (IDL) in one. Immunophenotypic analysis revealed one SLL to be of T-cell derivation, while a monoclonal B-cell phenotype was found in the remaining 23 patients; 20 of these neoplasms co-expressed the pan-T-cell antigen Leu-1. This included three of the four patients with MZL and the patient with IDL. All SLLs with pseudofollicular growth centers stained for transferrin receptor. Additionally, a survey of 248 non-Hodgkin's lymphomas of all types revealed four of 70 patients with B-cell large cell lymphoma (LCL; diffuse histiocytic lymphoma, DHL) that also co-expressed the same Leu-1 antigen. Immunoperoxidase study of both frozen tissue sections and cytocentrifuge preparations eliminated the limitations of faint antigen expression and/or interstitial immunoglobulin staining. In addition to detailing the immunophenotype of SLL, the immunologic kinship of MZL/IDL to SLL and the uncommon co-expression of Leu-1 in B-cell LCLs are demonstrated.

Malignant lymphoma with primary presentation in the spleen. A study of 20 patients

We describe 20 adult patients with malignant lymphoma with primary presentation in the spleen. The most common presenting symptoms were fever, malaise, and weight loss. Physical examination revealed prominent splenomegaly without palpable lymphadenopathy. Small lymphocytic lymphoma was the most frequent histologic type (11/20), followed by large cell lymphoma and mixed cell lymphoma (3/20 each). Bone marrow involvement was found in ten of 17 patients. At laparotomy, lymph node involvement, usually retroperitoneal, was found in six of 13 patients. There was liver involvement in seven of 15 patients. Follow-up has been relatively short, with an average of 24 months (range, one to 48 months). Four patients died as a result of progressive disease, one died of sepsis after splenectomy, and one died two years after diagnosis of a stroke. The prognosis in primary splenic lymphoma appears to be similar to that in nodal lymphoma.

Chronic lymphocytic leukemia in young adults

The occurrence of chronic lymphocytic leukemia (CLL), B-cell type, is thought to be distinctly uncommon in patients younger than 40 years of age. Previous case reports of CLL in young adults and children were published before the widespread use of immunologic surface markers in the diagnosis of lymphoproliferative disorders. The authors report four patients with B-cell CLL, all diagnosed with the aid of immunologic markers. The patients were 30 years of age or younger at the time of diagnosis. Their subsequent course has been similar to B-cell CLL in the older age group: one is alive without progression of disease 30 months after diagnosis; one has shown progression of the disease but is alive, after chemotherapy, 36 months after diagnosis; while the other two had continued progression of disease and died, one at six and a half years and the other at 14 months, after diagnosis. The occurrence of B-cell CLL in young adults and its potential implications are discussed.

Pre-B cell acute lymphoblastic leukemia in the newborn

Leukemia in the newborn is an infrequent disease that has not been well defined using modern laboratory techniques. We describe two infants, one at birth and one at four weeks, with acute lymphoblastic leukemia. The blasts from each patient were studied in great detail, using a battery of cytochemical and immunologic procedures in addition to ultrastructural studies. Immunologic cell marker studies, not previously reported in congenital leukemia, showed the lymphoblasts from each infant to be of the pre-B cell phenotype. Each infant relapsed, one after a 17-week clinical remission and the other after a 44-week remission. The former has died while the latter is in a second remission. The subtype of pre-B cell acute lymphoblastic leukemia (ALL) which in childhood appears to confer an unfavorable prognosis, may have the same significance in neonatal ALL.