Abstract OT2-01-10: Pilot study of carboplatin, nab-paclitaxel and pembrolizumab for metastatic triple-negative breast cancer (ongoing clinical trial)

BACKGROUND. Triple-negative breast cancer (TNBC) is associated with an aggressive phenotype and decreased survival. TNBC is characterized by tumor-infiltrating lymphocytes (TIL) which predict for a better prognosis and likely reflect immune recognition of tumor-associated antigens by TIL. However, potent immune suppressive signals exist in the tumor microenvironment such as those mediated by PD-1 with its ligand, PD-L1. Therefore, to test the validity of decreasing PD-1/PD-L1-mediated immune suppression, a Phase Ib study of single-agent pembrolizumab in 32 patients with advanced TNBC showed a partial response of 16.1% and stable disease of 9.7%, thereby attesting to the effectiveness of single-agent pembrolizumab in these patients. Other studies have demonstrated that cytotoxic chemotherapy favorably modulates immunity against cancer and there is therefore a strong rationale to combine chemotherapy with an immune modulator such as pembrolizumab for the treatment of mTNBC.

TRIAL DESIGN. This is an investigator-initiated, industry-sponsored (Merck) pilot study of carboplatin (C), nab-paclitaxel (N) and pembrolizumab (P) in 30 patients with metastatic (m) TNBC. Eligible patients will receive 3 cycles of CNP, with each cycle consisting of C (AUC 6 on days 1 of a 21-day cycle), N (100 mg/m2 IV on days 1, 8 and 15 of a 21-day cycle), and P (200 mg IV on day 15 of each cycle). After completion of 3 cycles CNP, patients with responding or stable disease by RECIST 1.1 criteria will be eligible for additional cycle(s) of CNP.

ELIGIBILITY CRITERIA. Patients must have radiologically measurable mTNBC, an ECOG performance status of 0-1, must not have received more than 2 prior therapies for this disease, and must be willing to undergo a preliminary biopsy of a metastatic focus for research purposes. A second post-treatment biopsy will be encouraged but will not be mandated.

SPECIFIC AIMS. The primary objective is to determine overall response rate (ORR) in patients treated with CNP. The secondary objectives are to determine progression-free survival (PFS) and safety/tolerability of CNP. Correlative objectives include the identification of pathologic and genomic correlates of response to CNP.

STATISTICAL METHODS. Clinical response will be scored using RECIST 1.1 criteria. Under the proposed treatment, the expected clinical response is about 35%. With the precision of the 2-sided 95% confidence interval for the response rate set to 0.17 (the distance to the expected response rate of 35%), the sample size required for the study is 30 patients. The true response rate of therapy will be estimated based on the number of responses using a binomial distribution and its confidence intervals will be estimated using Wilson's method. The Kaplan-Meier method will be used to estimate PFS. Factors including pathologic and genomic correlates that predict survival outcomes will be identified by Cox model or extensions of the Cox model.

TARGET ACCRUAL. We plan to enroll 30 patients over 2 years, with the first patient expected to be enrolled in September 2016.

CONTACT INFORMATION. Joseph Baar, MD, PhD. Seidman Cancer Center of University Hospitals Case Medical Center. E-mail: joseph.baar@uhhospitals.org.

Citation Format: Baar J, Abraham J, Silverman P, Budd GT, Vinayak S, Varadan V, Moore H, Montero A, Fu P. Pilot study of carboplatin, nab-paclitaxel and pembrolizumab for metastatic triple-negative breast cancer (ongoing clinical trial) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT2-01-10.

Abstract OT1-01-02: Pilot trial of a type I polarized autologous dendritic cell vaccine incorporating tumor blood vessel antigen-derived peptides in patients with metastatic breast cancer

BACKGROUND. Cancer vaccines based on tumor-associated antigens are rarely curative in advanced cancer. This limitation relates to the heterogeneity of cancer due to defects in antigen presentation and altered immunophenotypes. Therefore, another method to promote anti-tumor immunity is to prime T cells against tumor-associated stromal cells. We have reported that IL-12 gene-therapy of established HLA-A2neg B16 melanomas in HLA-A2 transgenic (Tg) mice resulted in CD8+ T cell-mediated immunity against the host HLA-A2+ stromal cells within the tumor microenvironment (TME). We have also shown that vaccines based on a subset of tumor blood vessel antigen (TBVA)-derived peptides (DLK1310-318, EphA2883-891, HBB31-39, NRP1433-441, RGS55-13 and TEM1691-700) prevented HLA-A2neg MC38 tumor establishment and promoted the regression of melanomas in HLA-A2 Tg mice by CD8+ T cell targeting of HLA-A2+ pericytes and vascular endothelial cells in the TME.

TRIAL DESIGN. Based on this pre-clinical data, we are undertaking a Susan G. Komen-funded (IIR13261822; IND 15722) IRB-approved clinical trial of chemo-immunotherapy using the immunomodulatory drug gemcitabine (GEM) to suppress tumor infiltrating suppressor cells such as myeloid-derived suppressor cells (MDSC) and regulatory T cells (Tregs) with a dendritic cell (DC) vaccine pulsed with the above six HLA-A2-presented TBVA-derived peptides (DC-TBVA) in 30 HLA-A2+ patients with metastatic breast cancer (MBC). Eligible patients will first undergo leukapheresis for the generation of the DC-TBVA vaccine. Patients will then receive 3 cycles of GEM, 1000 mg/m2 IV on days 1 and 8 of a 21-day cycle for 3 cycles. Patients will then receive the DC-TBVA vaccine administered twice intradermally 7 days apart.

ELIGIBILITY CRITERIA. Patients must be HLA-A2+ and have radiologically measurable MBC, an ECOG performance status of 0-1 and not have any active immune disorders. Prior GEM therapy is acceptable as long as the last dose was ≥ 3 months from registration on this study. Patients may not be on steroids.

SPECIFIC AIMS. The 4 specific aims are to 1) assess the safety of GEM + αDC1-TBVA vaccination, 2) assess the clinical response of MBC to GEM + αDC1-TBVA vaccination, 3) determine the clinical efficacy of GEM + αDC1-TBVA vaccination in generating Tc1 immunity, and 4) correlate changes in MDSC and Tregs with the generation of anti-TBVA Tc1-cell immunity

STATISTICAL METHODS. Clinical response: if the response rate is less than 10%, then there is probability 0.05 or less of accepting the vaccine therapy; if the response rate is bigger than 32%, then the probability of rejecting the combination is less than 0.2. While the secondary goals of the study are exploratory, there is sufficient statistical power to identify moderate to large effects (i.e., there will be statistical power >.80 to detect changes from baseline in the different immune function parameters that are >0.6 standard deviations of the parameter.)

TARGET ACCRUAL. We will enroll 30 patients over 3 years, with the first patient expected to be enrolled in July 2015.

CONTACT INFORMATION. Joseph Baar, MD, PhD. Seidman Cancer Center. E-mail: joseph.baar@uhhospitals.org.

Citation Format: Baar J, Storkus W, Finke J, Butterfield L, Lazarus H, Reese J, Brufsky A, Downes K, Budd GT, Fu P. Pilot trial of a type I polarized autologous dendritic cell vaccine incorporating tumor blood vessel antigen-derived peptides in patients with metastatic breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT1-01-02.

MUC1 expression in early-stage triple-negative breast cancer

Abstract #3009

Background. Triple-negative breast cancer (TNBC) comprises ∼10-15% of newly-diagnosed early-stage breast cancer. Most TN tumors are high grade and have a high incidence of recurrence and distant metastases. Patients with early stage TNBC usually do not receive any maintenance systemic therapy beyond standard cytotoxic chemotherapy and may therefore benefit from novel experimental therapies, including immunotherapy. MUC1 is a tumor antigen expressed on differentiated tumor cells, including BC, and therefore represents an ideal target for MUC1-based vaccination. In this study, we evaluated TNBC for the expression of MUC1 by immunohistochemical (IHC) analysis.
 Material and Methods. Fifty-three cases of ER(-) PR(-) HER-2/neu(-) early-stage BC were evaluated for expression of the MUC1 glycoprotein by IHC stain analysis. Immunoreactivity was graded based on the intensity and percent of tumor cells staining for MUC1. Intensity of staining was graded as negative (0), positive (1) or strongly-positive (2), and the percent of tumor cells staining positively was graded from 0 to 100%. A specimen was considered positive if immunoreactive cells were found in at least 5% of tumor cells. An overall score of 0 to 2.0 was then calculated for each case by multiplying the intensity of staining by the percent of tumor cells staining positively.
 Results. Forty nine of the fifty three cases of TNBC (92%) were MUC1+ by IHC stain analysis. The mean score was 0.90, with a range of 0 to 1.9. Cases were evenly distributed over this range, and the majority of cases (66%) exhibited moderate to strong expression of MUC1 (score 0.5 to 1.90). A minority of cases (26%) demonstrated weak expression, and 8% of cases lacked expression of MUC1 by study criteria.
 Discussion. MUC1 expression has been documented in the epithelium of secretory tubules, acini, and intralobular ducts of normal breast tissue and in breast carcinoma of undefined subtype. However, this is the first study to specifically evaluate TNBC for the expression of MUC1. The results of our study suggest that the vast majority of cases of early stage TNBC express MUC1. Since other MUC1+ tumors such as prostate, pancreatic and ER+ breast cancer have been successfully vaccinated with MUC1-based peptide vaccines, this study suggests that consideration may be given to patients with early stage TNBC as possible candidates for such novel MUC1-based vaccines after having completed standard therapies for TNBC.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3009.

Ectomycorrhizal root development in wet Alder carr forests in response to desiccation and eutrophication

Effects of desiccation and eutrophication on ectomycorrhizal (ECM) root development in wet Alder carr forests in The Netherlands were studied. In northwestern Europe, wet Alder carr forests are found mostly in peatlands and along streams, forming an important component of wetland ecosystems. The dominant tree species in wet Alder carr forests is Alnus glutinosa (L.) Gaertn. (Black alder), which associates with ectomycorrhizal fungi. During recent decades, wet Alder carr forests in Europe have declined because of desiccation and eutrophication, particularly in The Netherlands. In the present study, the number of root tips of A. glutinosa trees was highest in an undisturbed wet Alder carr forest in a peatland area. Eutrophication in the peatland area significantly inhibited ectomycorrhizal (ECM) root development of A. glutinosa. In the eutrophied forest, ECM root tips were observed only close to A. glutinosa trees growing on hummocks. The concentrations of nitrate and potassium in soil water of the eutrophied forest were significantly higher than in the undisturbed forest, while magnesium and iron concentrations and the pH were significantly lower. The number of ECM root tips of A. glutinosa in a desiccated forest along a stream was generally lower than in an undisturbed wet Alder carr forest on waterlogged soil in the same area. The sulphate concentration in soil water in the desiccated forest was significantly higher than in the forest on waterlogged soil. ECM root development of A. glutinosa may have been negatively affected by the chemical composition of the soil water.

Low ectomycorrhizal inoculum potential and diversity from soils in and near ancient forests of bristlecone pine (Pinus longaeva)

Intersite variation in ectomycorrhizal (ECM) inoculum potential in soils from 16 sites located in arid subalpine areas of the White Mountains of California was quantified. The study sites included valleys dominated by big sagebrush (Artemisia tridentata Nutt.) and mountainsides dominated by ancient Great Basin bristlecone pine (Pinus longaeva Bailey). ECM inoculum potential was not detected at three of four valley sites nor in 42% of forest soil samples. Only 10 mycorrhizal species were detected in bioassays, and four of those accounted for 94.5% of all colonized seedlings, in order of decreasing abundance these were Pyronemataceae sp., Rhizopogon sp., Wilcoxina rehmii Yang & Korf, and Cenococcum sp. These species were identified also from in situ mycorrhizal roots. The abundance of the dominant Pyronemataceae sp. was significantly positively correlated with pH, which at all forest sites was high compared with typical conifer forest soils. Our results show that the ECM inoculum potential of soils is low, homogeneous, and spatially restricted in these ancient high-elevation forests.Key words: fungal community, molecular ecology, spore dispersal.

Oncology thinking cap: scaffolded use of a simulation to learn clinical trial design

BACKGROUND

Physicians often are called on to participate in and interpret clinical trials, but their training in this area may not provide them with the inquiry skills that are needed. Simulations have the potential to be a promising tool for helping medical students learn the skills involved in clinical trial design. However, simulations may be complex and require additional scaffolding to support learning.

DESCRIPTION

The goal of this study was to teach aspects of cancer clinical trial design through the scaffolded use of a simulation, the Oncology Thinking Cap. The software-based scaffolding provided guidance in designing the trial. Subsequently, the simulation allowed students to run the designed trial, which produces detailed patient histories. This feedback then could be used to redesign the trial.

EVALUATION

Twenty-four 4th-year medical students were asked to design a clinical trial in advance, on paper, to test a new anticancer drug. Student groups then designed and simulated running the clinical trial assisted by the software environment. Instructional effectiveness was measured using a pretest-posttest design that included having students (a) write a group research proposal and (b) individually critique a flawed proposal. At the group level (N = 6 groups), students demonstrated a 34% increase in the number of elements of a clinical trial that they included in their research proposals. At the individual level (N = 24), students improved by 48% in their critiques of flawed proposals.

CONCLUSIONS

Scaffolding embedded in the simulator is a promising approach to helping students learn about clinical trial design.

Primary non-Hodgkin's lymphoma of bone

Primary non-Hodgkin's lymphoma of bone (PLB) constitutes approximately 5% of all extranodal non-Hodgkin's lymphoma (NHL) and 7% of primary bone tumors. The peak incidence for PLB is in the fifth decade, with a slight preponderance of males over females. The presenting symptoms usually consist of localized bone pain and occasionally a palpable mass. Most patients with PLB have B-cell tumors with a diffuse mixed-cell or diffuse large cell histology. While most patients present with early-stage disease, it is not clear whether such patients benefit from combined-modality therapy (CMT) consisting of radiation therapy (RT) and chemotherapy (CT) compared with either RT or CT alone. However, there is strong evidence that CMT is beneficial in the treatment of localized NHL, and these results might be applicable to the therapy for PLB. Nevertheless, only a phase III randomized, controlled clinical trial will determine whether CMT is superior to either CT or RT alone.

Potentiation of E7 antisense RNA-induced antitumor immunity by co-delivery of IL-12 gene in HPV16 DNA-positive mouse tumor

Down-regulation of oncogene expression by antisense-based gene therapy has been extensively studied, and in some cases, therapeutic effects have been demonstrated. We have previously shown that down-regulation of HPV16 E6 and E7 gene expression inhibited HPV DNA-positive C3 mouse tumor growth. Although not all of the tumor cells were transfected by pU6E7AS plasmid, complete tumor regression was achieved if the tumor size was small at the start of therapy in a syngeneic host. This suggests that some other antitumor mechanisms may be involved in addition to the direct down-regulation of HPV16 E7 oncogene expression by the antisense effect of E7AS. In the current study, we demonstrated that E7AS induces tumor cell apoptosis. More importantly, a strong antitumor immune response was elicited in the pU6E7AS-treated and tumor-regressed mice. There was no tumor growth after rechallenging the tumor-regressed mice with 1 million C3 cells. This E7AS-induced antitumor immune response was augmented by co-delivery of mIL-12 cytokine gene. The combination therapy strategy resulted in complete regression of 26 of 28 (93%) tumors. Only 12 of 31 (38%) tumors from the group treated with pU6E7AS alone and 14 of 28 (50%) tumors from the group treated with pCMVmIL-12 alone had completely regressed. Complete regression was also demonstrated in tumors located 1 cm from the treated tumors, which indicates that a systemic antitumor effect was induced by E7AS and mIL-12. Immunohistochemistry demonstrated that a significant amount of CD4+ and CD8+ cells infiltrated into tumors treated with pU6E7AS, pCMVmIL-12 and pU6E7AS+pCMVmIL-12. These data indicate that host immunity is an important factor for antisense-based gene therapy approach which can be further enhanced by combination with cytokine gene therapy.

Autologous human monocyte-derived dendritic cells genetically modified to express melanoma antigens elicit primary cytotoxic T cell responses in vitro: enhancement by cotransfection of genes encoding the Th1-biasing cytokines IL-12 and IFN-alpha

DNA-based immunization strategies designed to elicit cellular antitumor immunity offer an attractive alternative to protein- or peptide-based approaches. In the present study we have evaluated the feasibility of DNA vaccination for the induction of CTL reactivity to five different melanoma Ags in vitro. Cultured, monocyte-derived dendritic cells (DC) were transiently transfected with plasmid DNA encoding human MART-1/Melan-A, pMel-17/gp100, tyrosinase, MAGE-1, or MAGE-3 by particle bombardment and used to stimulate autologous PBMC responder T cells. CTL reactivity to these previously identified melanoma Ags was reproducibly generated after two or three stimulations with genetically modified DC. Co-ordinate transfection of two melanoma Ag cDNAs into DC promoted CTL responders capable of recognizing epitopes from both gene products. Coinsertion of genes encoding the Th1-biasing cytokines IL-12 or IFN-alpha consistently enhanced the magnitude of the resulting Ag-specific CTL reactivity. Importantly, DC transfected with a single melanoma Ag cDNA were capable of stimulating Ag-specific CTL reactivity restricted by multiple host MHC alleles, some of which had not been previously identified. These results support the inherent strengths of gene-based vaccine approaches that do not require prior knowledge of responder MHC haplotypes or of relevant MHC-restricted peptide epitopes. Given previous observations of in situ tumor HLA allele-loss variants, DC gene vaccine strategies may elicit a greater diversity of host therapeutic immunity, thereby enhancing the clinical utility and success of such approaches.

Interferon-alpha gene therapy for cancer: retroviral transduction of fibroblasts and particle-mediated transfection of tumor cells are both effective strategies for gene delivery in murine tumor models

Stable transfection of tumor cells with IFN-alpha genes has been shown to result in abrogation of tumor establishment and induction of antitumor immunity. However, strategies suitable for the clinical application of IFN-alpha gene therapy for cancer have not been reported. In this study, we investigated two gene delivery systems capable of mediating the local paracrine production of high levels of biologically active IFN-alpha in murine tumor models: retroviral transduction of fibroblasts and particle-mediated transfection of tumor cells. In spite of the antiproliferative effects of IFN-alpha, it was possible to obtain stable retroviral producer cell lines and transduce a variety of murine tumor cells including syngeneic fibroblasts to stably secrete 2000-5000 U (40-100 ng) murine IFN-alpha/10(6) cells/24 h. IFN-alpha transduction of tumor cells abrogated tumorigenicity in establishment models and induced antitumor immunity in several murine tumor model systems. Importantly, IFN-alpha gene delivery using retrovirally transduced syngeneic fibroblasts was capable of suppressing the establishment of the poorly immunogenic TS/A mouse mammary adenocarcinoma and induced antitumor immunity. Particle mediated transient transfection of tumor cells using the gene gun led to the production of up to 20,000 U IFN-alpha/10(6) cells during the first 24 h and proved to be equally effective in suppressing establishment of TS/A adenocarcinoma and inducing antitumor immunity. These results suggest that retroviral transduction of autologous fibroblasts can serve as an effective gene delivery method for IFN-alpha gene therapy of cancer. Particle-mediated transfection of freshly isolated tumor cells may represent a clinically attractive alternative approach for nonviral gene delivery. Both strategies circumvent the difficulties in routinely establishing primary tumor cell lines from the vast majority of human cancers.

Analysis of a hot spot for DNA insertion suggests a mechanism for Ig switch recombination

We recently reported that transfected DNA inserts into the VDJ-Cmu intron much more frequently than into average DNA, and that insertion within this intron occurs preferentially into the switch region. To gain information about the mechanisms involved in DNA insertion, we sequenced the 5' and 3' junctions of typical transformants. Although the junction sequences did not indicate a preferred insertion motif within the switch region, our results suggest that joining of the transfected and chromosomal DNAs is facilitated by short regions of identity. Our analysis of the insertions into the non-switch part of the intron suggests that breakage of the chromosomal DNA occurs preferentially at sites that are flanked by short complementary sequences. This correlation suggests that the self-complementary DNA might form short stem-loops, which, in turn, are prone to enzymatic cleavage and thus facilitate the insertion of transfected DNA. A model is proposed in which this effect can account for both the higher than average frequency of insertion into the VDJ-Cmu intron and the preference for the switch region within this intron. An extension of this model is proposed to explain why the repetitive switch regions are the preferred breakage/rejoining sites for isotype switch rearrangements.

Analysis of a hot spot for DNA insertion suggests a mechanism for Ig switch recombination

We recently reported that transfected DNA inserts into the VDJ-Cmu intron much more frequently than into average DNA, and that insertion within this intron occurs preferentially into the switch region. To gain information about the mechanisms involved in DNA insertion, we sequenced the 5' and 3' junctions of typical transformants. Although the junction sequences did not indicate a preferred insertion motif within the switch region, our results suggest that joining of the transfected and chromosomal DNAs is facilitated by short regions of identity. Our analysis of the insertions into the non-switch part of the intron suggests that breakage of the chromosomal DNA occurs preferentially at sites that are flanked by short complementary sequences. This correlation suggests that the self-complementary DNA might form short stem-loops, which, in turn, are prone to enzymatic cleavage and thus facilitate the insertion of transfected DNA. A model is proposed in which this effect can account for both the higher than average frequency of insertion into the VDJ-Cmu intron and the preference for the switch region within this intron. An extension of this model is proposed to explain why the repetitive switch regions are the preferred breakage/rejoining sites for isotype switch rearrangements.

The Ig heavy chain switch region is a hotspot for insertion of transfected DNA

The Ig heavy chain class switch usually occurs by breaking and rejoining DNA in the switch (S) regions, which consist of tandemly repeated sequences 5' of the constant region exons. Various studies have suggested that S DNA can also recombine with non-S sequences. To measure the frequency of such recombination events, the hybridoma cell line igm692, a deletion mutant that lacks the C mu 1 and C mu 2 exons and the 3' end of the S mu region, was transfected with a fragment bearing the C mu 1-2 exons, but no S mu DNA. Insertion of this fragment into the residual VDJ-C mu intron of igm692 can restore a functional mu gene, yielding a transformant that is detected as a plaque-forming cell (PFC). PFC comprise approximately 8 x 10(-7) of the surviving transfected cells. In 10 of 12 PFCs, the C mu 1-2 fragment inserted into the 2.5-kb residual S mu region, whereas insertion in two cases occurred in the 3.5-kb segment 5' of S mu. Using a PCR assay to measure the frequency of insertion of the transferred fragment elsewhere in the hybridoma genome, we found that approximately 9% of the surviving transfected cells had stably acquired the C mu 1-2 fragment. These results indicate that the S mu region is approximately 100-fold more recombinogenic than the average genomic site, and approximately 7-fold more recombinogenic than the non-S mu segment of the residual VDJ-C mu, i.e., the S mu region is a hotspot for insertion of transfected DNA.

The Ig heavy chain switch region is a hotspot for insertion of transfected DNA

The Ig heavy chain class switch usually occurs by breaking and rejoining DNA in the switch (S) regions, which consist of tandemly repeated sequences 5' of the constant region exons. Various studies have suggested that S DNA can also recombine with non-S sequences. To measure the frequency of such recombination events, the hybridoma cell line igm692, a deletion mutant that lacks the C mu 1 and C mu 2 exons and the 3' end of the S mu region, was transfected with a fragment bearing the C mu 1-2 exons, but no S mu DNA. Insertion of this fragment into the residual VDJ-C mu intron of igm692 can restore a functional mu gene, yielding a transformant that is detected as a plaque-forming cell (PFC). PFC comprise approximately 8 x 10(-7) of the surviving transfected cells. In 10 of 12 PFCs, the C mu 1-2 fragment inserted into the 2.5-kb residual S mu region, whereas insertion in two cases occurred in the 3.5-kb segment 5' of S mu. Using a PCR assay to measure the frequency of insertion of the transferred fragment elsewhere in the hybridoma genome, we found that approximately 9% of the surviving transfected cells had stably acquired the C mu 1-2 fragment. These results indicate that the S mu region is approximately 100-fold more recombinogenic than the average genomic site, and approximately 7-fold more recombinogenic than the non-S mu segment of the residual VDJ-C mu, i.e., the S mu region is a hotspot for insertion of transfected DNA.

Primary non-Hodgkin's lymphoma of bone. A clinicopathologic study

BACKGROUND

This study relates our experience in the diagnosis and treatment of a rare clinical entity, non-Hodgkin's primary lymphoma of bone.

METHODS

Seventeen cases of patients with primary lymphoma of bone diagnosed and treated at a single institution between 1975 and 1992 are reviewed. Ten patients received combined-modality therapy, consisting of an anthracycline-containing combination chemotherapy (CT) regimen, followed by adjuvant radiotherapy (RT) to the primary site of disease. Five patients were treated with CT alone; one patient received RT alone; and one patient was treated with CT after emergency RT for spinal cord compression.

RESULTS

Thirteen patients presented with Stage I disease, two with Stage II; and two with Stage IV disease (multiple bony sites only). Thirteen patients had an intermediate-grade diffuse large cell lymphoma; two had an intermediate-grade mixed small and large cell lymphoma; and two had a high-grade lymphoma (one immunoblastic and one small non-cleaved cell lymphoma). The overall response rate was 94% (18% complete response, 58% partial response 1, and 18% partial response 2). Thirteen patients are alive and disease-free at a median of 29 months; 10 of these received CT+RT, and 3 received CT alone. Three patients have died; one of these received CT+RT and one CT alone, and one relapsed immediately after CT. One patient, who was initially treated with RT and then with CT+RT after relapse, was lost to follow-up 40 months from the start of treatment.

CONCLUSIONS

Because experience in the literature suggests a 50% distant relapse rate in primary lymphoma of bone treated with RT alone, our policy is to treat all patients with combined-modality therapy (CT+RT). However, only a Phase III randomized, controlled clinical trial will determine whether CT+RT is superior to either modality alone.

Analyzing the same data in two ways: a demonstration model to illustrate the reporting and misreporting of clinical trials

The methods used to analyze and interpret clinical trials of chemotherapy may have a major impact on the conclusions that are drawn in papers reporting them. To illustrate this problem, we constructed a hypothetical clinical trial in which patients with metastatic cancer were treated with chemotherapy. The following two articles provide reports of this trial, analyzed by methods that we would interpret as being of low and high quality, respectively. In the present report, we describe briefly the methodological differences that led to the opposite conclusions based on this single set of data. The errors of reporting and omissions of the first article (A) are similar to those that have been extracted from recent issues of the Journal of Clinical Oncology and other leading cancer journals, although they have not all appeared within a single report. This demonstration model illustrates problems in the reporting of clinical trials and suggests guidelines for improved reporting.