Spatially aware deep learning reveals tumor heterogeneity patterns that encode distinct kidney cancer states

Clear cell renal cell carcinoma (ccRCC) is molecularly heterogeneous, immune infiltrated, and selectively sensitive to immune checkpoint inhibition (ICI). However, the joint tumor-immune states that mediate ICI response remain elusive. We develop spatially aware deep-learning models of tumor and immune features to learn representations of ccRCC tumors using diagnostic whole-slide images (WSIs) in untreated and treated contexts (n = 1,102 patients). We identify patterns of grade heterogeneity in WSIs not achievable through human pathologist analysis, and these graph-based "microheterogeneity" structures associate with PBRM1 loss of function and with patient outcomes. Joint analysis of tumor phenotypes and immune infiltration identifies a subpopulation of highly infiltrated, microheterogeneous tumors responsive to ICI. In paired multiplex immunofluorescence images of ccRCC, microheterogeneity associates with greater PD1 activation in CD8+ lymphocytes and increased tumor-immune interactions. Our work reveals spatially interacting tumor-immune structures underlying ccRCC biology that may also inform selective response to ICI.

Spatially aware deep learning reveals tumor heterogeneity patterns that encode distinct kidney cancer states

Clear cell renal cell carcinoma (ccRCC) is molecularly heterogeneous, immune infiltrated, and selectively sensitive to immune checkpoint inhibition (ICI). Established histopathology paradigms like nuclear grade have baseline prognostic relevance for ccRCC, although whether existing or novel histologic features encode additional heterogeneous biological and clinical states in ccRCC is uncertain. Here, we developed spatially aware deep learning models of tumor- and immune-related features to learn representations of ccRCC tumors using diagnostic whole-slide images (WSI) in untreated and treated contexts (n = 1102 patients). We discovered patterns of nuclear grade heterogeneity in WSI not achievable through human pathologist analysis, and these graph-based "microheterogeneity" structures associated with PBRM1 loss of function, adverse clinical factors, and selective patient response to ICI. Joint computer vision analysis of tumor phenotypes with inferred tumor infiltrating lymphocyte density identified a further subpopulation of highly infiltrated, microheterogeneous tumors responsive to ICI. In paired multiplex immunofluorescence images of ccRCC, microheterogeneity associated with greater PD1 activation in CD8+ lymphocytes and increased tumor-immune interactions. Thus, our work reveals novel spatially interacting tumor-immune structures underlying ccRCC biology that can also inform selective response to ICI.

Induction of a colitogenic phenotype in Th1-like cells depends on interleukin-23 receptor signaling

Interleukin-23 receptor plays a critical role in inducing inflammation and autoimmunity. Here, we report that Th1-like cells differentiated in vitro with IL-12 + IL-21 showed similar IL-23R expression to that of pathogenic Th17 cells using eGFP reporter mice. Fate mapping established that these cells did not transition through a Th17 cell state prior to becoming Th1-like cells, and we observed their emergence in vivo in the T cell adoptive transfer colitis model. Using IL-23R-deficient Th1-like cells, we demonstrated that IL-23R was required for the development of a highly colitogenic phenotype. Single-cell RNA sequencing analysis of intestinal T cells identified IL-23R-dependent genes in Th1-like cells that differed from those expressed in Th17 cells. The perturbation of one of these regulators (CD160) in Th1-like cells inhibited the induction of colitis. We thus uncouple IL-23R as a purely Th17 cell-specific factor and implicate IL-23R signaling as a pathogenic driver in Th1-like cells inducing tissue inflammation.

Integrative clinical and molecular characterization of translocation renal cell carcinoma

Translocation renal cell carcinoma (tRCC) is a poorly characterized subtype of kidney cancer driven by MiT/TFE gene fusions. Here, we define the landmarks of tRCC through an integrative analysis of 152 patients with tRCC identified across genomic, clinical trial, and retrospective cohorts. Most tRCCs harbor few somatic alterations apart from MiT/TFE fusions and homozygous deletions at chromosome 9p21.3 (19.2% of cases). Transcriptionally, tRCCs display a heightened NRF2-driven antioxidant response that is associated with resistance to targeted therapies. Consistently, we find that outcomes for patients with tRCC treated with vascular endothelial growth factor receptor inhibitors (VEGFR-TKIs) are worse than those treated with immune checkpoint inhibitors (ICI). Using multiparametric immunofluorescence, we find that the tumors are infiltrated with CD8⁺ T cells, though the T cells harbor an exhaustion immunophenotype distinct from that of clear cell RCC. Our findings comprehensively define the clinical and molecular features of tRCC and may inspire new therapeutic hypotheses.

Building tools for machine learning and artificial intelligence in cancer research: best practices and a case study with the PathML toolkit for computational pathology

Imaging datasets in cancer research are growing exponentially in both quantity and information density. These massive datasets may enable derivation of insights for cancer research and clinical care, but only if researchers are equipped with the tools to leverage advanced computational analysis approaches such as machine learning and artificial intelligence. In this work, we highlight three themes to guide development of such computational tools: scalability, standardization, and ease of use. We then apply these principles to develop PathML, a general-purpose research toolkit for computational pathology. We describe the design of the PathML framework and demonstrate applications in diverse use-cases. PathML is publicly available at www.pathml.com.

Integrative molecular characterization of sarcomatoid and rhabdoid renal cell carcinoma

Sarcomatoid and rhabdoid (S/R) renal cell carcinoma (RCC) are highly aggressive tumors with limited molecular and clinical characterization. Emerging evidence suggests immune checkpoint inhibitors (ICI) are particularly effective for these tumors, although the biological basis for this property is largely unknown. Here, we evaluate multiple clinical trial and real-world cohorts of S/R RCC to characterize their molecular features, clinical outcomes, and immunologic characteristics. We find that S/R RCC tumors harbor distinctive molecular features that may account for their aggressive behavior, including BAP1 mutations, CDKN2A deletions, and increased expression of MYC transcriptional programs. We show that these tumors are highly responsive to ICI and that they exhibit an immune-inflamed phenotype characterized by immune activation, increased cytotoxic immune infiltration, upregulation of antigen presentation machinery genes, and PD-L1 expression. Our findings build on prior work and shed light on the molecular drivers of aggressivity and responsiveness to ICI of S/R RCC.

Sarcomatoid and rhabdoid tumours are highly aggressive forms of renal cell carcinoma that are also responsive to immunotherapy. In this study, the authors perform a comprehensive molecular characterization of these tumours discovering an enrichment of specific alterations and an inflamed phenotype.

An IL-27-Driven Transcriptional Network Identifies Regulators of IL-10 Expression across T Helper Cell Subsets

Interleukin-27 (IL-27) is an immunoregulatory cytokine that suppresses inflammation through multiple mechanisms, including induction of IL-10, but the transcriptional network mediating its diverse functions remains unclear. Combining temporal RNA profiling with computational algorithms, we predict 79 transcription factors induced by IL-27 in T cells. We validate 11 known and discover 5 positive (Cebpb, Fosl2, Tbx21, Hlx, and Atf3) and 2 negative (Irf9 and Irf8) Il10 regulators, generating an experimentally refined regulatory network for Il10. We report two central regulators, Prdm1 and Maf, that cooperatively drive the expression of signature genes induced by IL-27 in type 1 regulatory T cells, mediate IL-10 expression in all T helper cells, and determine the regulatory phenotype of colonic Foxp3⁺ regulatory T cells. Prdm1/Maf double-knockout mice develop spontaneous colitis, phenocopying ll10-deficient mice. Our work provides insights into IL-27-driven transcriptional networks and identifies two shared Il10 regulators that orchestrate immunoregulatory programs across T helper cell subsets.

Zhang et al. construct a transcriptional network for IL-27-mediated Il10 production in CD4 T cells, characterize the function of 16 Il10 regulators, and uncover the role of two transcription factors, Prdm1 and Maf, in driving Il10 production in all T helper cells and in maintaining immune homeostasis in the colon.

Abstract 2063: Deep natural language processing for automated ascertainment of cancer outcomes from clinician progress notes

Introduction: Clinical research using genomic datasets, such as AACR Project GENIE, requires outcomes such as cancer progression and response to contextualize molecular information. We are developing the “PRISSMM” (Pathology, Radiology/Imaging, Signs/Symptoms, Medical oncologist assessment, and tumor Markers) framework for clinical curation of genomic data. Natural language processing (NLP) models based on this framework could accelerate curation of reproducible endpoints. However, the application of NLP at scale to extract outcomes from oncologist notes, which mix historical and current information, has been limited to date.

Methods: Medical oncologists' progress notes were reviewed for patients with lung cancer whose tumors were sequenced through an institutional precision medicine study from 2013-2018. For each note, curators recorded whether the assessment/plan indicated the presence of (a) any cancer, (b) progression/worsening of disease, and/or (c) response to therapy/improvement of disease. Next, a recurrent neural network was trained to extract the assessment/plan from each note. Finally, convolutional neural networks were trained on the assessments/plans to predict the probability that each curated outcome was present. Model performance was evaluated among a held-out 10% test subset of patients using the area under the receiver-operating characteristic curve (AUC) and area under the precision-recall curve (AUPRC). Associations between curated response or progression endpoints (generated using 10-fold cross-validation) and overall survival were measured using Cox models, treating the endpoints as time-varying covariates, among patients receiving palliative-intent systemic therapy.

Results: Results among 7,597 curated notes for 919 patients are indicated in the Table.

EndpointAUC of NLP models for identifying endpoint in the test setProportion of manually curated notes with endpointAUPRC of NLP models for identifying endpoint in the test setHR (95% CI) for mortality associated with endpoint, as manually curated, among patients receiving palliative- intent treatmentHR (95% CI) for mortality associated with endpoint, as predicted using NLP models using F1-optimal threshold probabilitiesAny evidence of lung cancer0.940.770.97N/AN/AProgression0.860.200.652.93 (2.33-3.67)2.49 (2.00-3.09)Response to treatment0.900.120.570.70 (0.47-1.03)0.45 (0.30-0.67)

Conclusion: Neural network NLP models can extract meaningful outcomes from oncologist notes for clinical curation of electronic health records at scale.

Citation Format: Kenneth L. Kehl, Wenxin Xu, Haitham A. Elmarakeby, Michael J. Hassett, Jackson Nyman, Bruce E. Johnson, Eliezer M. Van Allen, Deb Schrag. Deep natural language processing for automated ascertainment of cancer outcomes from clinician progress notes [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2063.

Genome-wide discovery of epistatic loci affecting antibiotic resistance in Neisseria gonorrhoeae using evolutionary couplings

Genome analysis should allow the discovery of interdependent loci that together cause antibiotic resistance. In practice, however, the vast number of possible epistatic interactions erodes statistical power. Here, we extend an approach that has been successfully used to identify epistatic residues in proteins to infer genomic loci that are strongly coupled. This approach reduces the number of tests required for an epistatic genome-wide association study of antibiotic resistance and increases the likelihood of identifying causal epistasis. We discovered 38 loci and 240 epistatic pairs that influence the minimum inhibitory concentrations of 5 different antibiotics in 1,102 isolates of Neisseria gonorrhoeae that were confirmed in a second dataset of 495 isolates. Many known resistance-affecting loci were recovered; however, the majority of associations occurred in unreported genes, such as murE. About half of the discovered epistasis involved at least one locus previously associated with antibiotic resistance, including interactions between gyrA and parC. Still, many combinations involved unreported loci and genes. While most variation in minimum inhibitory concentrations could be explained by identified loci, epistasis substantially increased explained phenotypic variance. Our work provides a systematic identification of epistasis affecting antibiotic resistance in N. gonorrhoeae and a generalizable approach for epistatic genome-wide association studies.

Single-cell RNA-seq identifies the neuropeptide NMU as a novel regulator of ILC2 function

Type 2 innate lymphoid cells (ILC2s) are important for both mucosal homeostasis as well as for initiation and progression of allergy and asthma. Alarmin cytokines produced by damaged or stressed epithelial cells activate ILC2s, however, the role of other pathways regulating the homeostatic versus inflammatory functions of ILC2s remain poorly defined. We generated transcriptional profiles of thousands of lung-resident ILCs isolated from mice challenged with either PBS or the alarmin cytokines IL-25 or IL-33 using massively parallel droplet-based single-cell RNA sequencing (scRNA-seq). We found significant transcriptional heterogeneity within activated ILCs and identified differentially expressed genes as potential novel regulators of ILC function. One of the genes, neuromedin U receptor 1 (NMUR1), is a receptor for the neuropeptide neuromedin U (NMU) and is specifically expressed by ILC2s and not by other immune cells. Nmur1 is particularly expressed by ILC2s at steady-state and after IL-25 treatment. In vivo NMU synergized with IL-25 to induce more severe airway inflammation than was seen with either IL-25 or NMU alone and this effect was dependent on ILCs. Mechanistically, IL-25 + NMU expanded highly proliferative and inflammatory ILCs with distinct transcriptional profiles and increased expression of IL-5 and IL-13. We observed reduced ILC2 frequency and function in NMU- or NMUR1-deficient mice after allergen challenge and found that ILCs from these mice had a lower score for an inflammatory ILC2 gene signature. Our data therefore establish a novel neuro-immune pathway that amplifies ILC2-driven airway inflammation.

Cerebrospinal fluid markers of extracellular matrix remodelling, synaptic plasticity and neuroinflammation before and after cranial radiotherapy

BACKGROUND

Advances in the treatment of brain tumours have increased the number of long-term survivors, but at the cost of side effects following cranial radiotherapy ranging from neurocognitive deficits to outright tissue necrosis. At present, there are no tools reflecting the molecular mechanisms underlying such side effects, and thus no means to evaluate interventional effects after cranial radiotherapy. Therefore, fluid biomarkers are of great clinical interest.

OBJECTIVE

Cerebrospinal fluid (CSF) levels of proteins involved in inflammatory signalling, synaptic plasticity and extracellular matrix (ECM) integrity were investigated following radiotherapy to the brain.

METHODS

Patients with small-cell lung cancer (SCLC) eligible for prophylactic cranial irradiation (PCI) were asked to participate in the study. PCI was prescribed either as 2 Gy/fraction to a total dose of 30 Gy (limited disease) or 4 Gy/fraction to 20 Gy (extensive disease). CSF was collected by lumbar puncture at baseline, 3 months and 1 year following PCI. Protein concentrations were measured using immunobased assays or mass spectrometry.

RESULTS

The inflammatory markers IL-15, IL-16 and MCP-1/CCL2 were elevated in CSF 3 months following PCI compared to baseline. The plasticity marker GAP-43 was elevated 3 months following PCI, and the same trend was seen for SNAP-25, but not for SYT1. The investigated ECM proteins, brevican and neurocan, showed a decline following PCI. There was a strong correlation between the progressive decline of soluble APPα and brevican levels.

CONCLUSION

To our knowledge, this is the first time ECM-related proteins have been shown to be affected by cranial radiotherapy in patients with cancer. These findings may help us to get a better understanding of the mechanisms behind side effects following radiotherapy.

3-Aminobenzamide Blocks MAMP-Induced Callose Deposition Independently of Its Poly(ADPribosyl)ation Inhibiting Activity

Cell wall reinforcement with callose is a frequent plant response to infection. Poly(ADP-ribosyl)ation is a protein post-translational modification mediated by poly(ADP-ribose) polymerases (PARPs). Poly(ADP-ribosyl)ation has well-known roles in DNA damage repair and has more recently been shown to contribute to plant immune responses. 3-aminobenzamide (3AB) is an established PARP inhibitor and it blocks the callose deposition elicited by flg22 or elf18, two microbe-associated molecular patterns (MAMPs). However, we report that an Arabidopsis parp1parp2parp3 triple mutant does not exhibit loss of flg22-induced callose deposition. Additionally, the more specific PARP inhibitors PJ-34 and INH₂BP inhibit PARP activity in Arabidopsis but do not block MAMP-induced callose deposition. These data demonstrate off-target activity of 3AB and indicate that 3AB inhibits callose deposition through a mechanism other than poly(ADP-ribosyl)ation. POWDERY MILDEW RESISTANT 4 (PMR4) is the callose synthase responsible for the majority of MAMP- and wound-induced callose deposition in Arabidopsis. 3AB does not block wound-induced callose deposition, and 3AB does not reduce the PMR4 mRNA abundance increase in response to flg22. Levels of PMR4-HA protein increase in response to flg22, and increase even more in flg22 + 3AB despite no callose being produced. The callose synthase inhibitor 2-deoxy-D-glucose does not cause similar impacts on PMR4-HA protein levels. Beyond MAMPs, we find that 3AB also reduces callose deposition induced by powdery mildew (Golovinomyces cichoracearum) and impairs the penetration resistance of a PMR4 overexpression line. 3AB thus reveals pathogenesis-associated pathways that activate callose synthase enzymatic activity distinct from those that elevate PMR4 mRNA and protein abundance.

Abstract A10: A distinct gene module for T cell dysfunction uncoupled from T cell activation and controlled by metallothioneins

Reversing the dysfunctional (also known as “exhausted”) T cell state that arises in cancer and chronic viral infections is the focus of therapeutic interventions; however, current therapies are effective in only some patients and for only some tumor types. To gain a deeper molecular understanding of the dysfunctional T cell state, we leveraged mouse models to analyze RNA profiles of CD8+ tumor-infiltrating lymphocytes (TILs) at various functional states. In a comparative study we identified metallothioneins, regulators of zinc metabolism, as drivers of T cell dysfunction and used genetic perturbation to identify, for the first time, a distinct gene module for T cell dysfunction that is uncoupled from T cell activation and associated with a CD8+ Treg signature. An analysis of TILs at single-cell resolution revealed that our dysfunction module negatively correlates with activation signatures also at the single-cell level, indicating that our uncoupled signatures for T cell dysfunction and activation can represent cell-intrinsic states. Clustering of the single-cells revealed a previously uncharacterized subpopulation of CD8+ TILs that was strongly enriched for our novel dysfunction signature, but not for activation signatures. This subpopulation was depleted of cells from a metallothionein KO mouse model in which T cell dysfunction was not observed, implying that we have indeed identified a phenotypically dysfunctional subpopulation. Using CRISPR/Cas9 genome editing we validate that Gata-3, a transcription factor expressed specifically in our identified subpopulation, is a driver of the dysfunctional phenotype in CD8+ TILs. Our results open novel avenues for specifically targeting the dysfunctional T cell state while leaving T cell activation programs intact.

Citation Format: Meromit Singer, Chao Wang, Le Cong, Nemanja D. Marjanovic, Monika S. Kowalczyk, Huiyuan Zhang, Jackson Nyman, Kaori Sakuishi, Sema Kurtulus, David Gennert, Junrong Xia, John YH Kwon, James Nevin, Rebecca H. Herbst, Itai Yanai, Orit Rozenblatt-Rosen, Vijay K. Kuchroo, Aviv Regev, Ana C. Anderson. A distinct gene module for T cell dysfunction uncoupled from T cell activation and controlled by metallothioneins. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2016 Oct 20-23; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2017;5(3 Suppl):Abstract nr A10.

A Distinct Gene Module for Dysfunction Uncoupled from Activation in Tumor-Infiltrating T Cells

Reversing the dysfunctional T cell state that arises in cancer and chronic viral infections is the focus of therapeutic interventions; however, current therapies are effective in only some patients and some tumor types. To gain a deeper molecular understanding of the dysfunctional T cell state, we analyzed population and single-cell RNA profiles of CD8(+) tumor-infiltrating lymphocytes (TILs) and used genetic perturbations to identify a distinct gene module for T cell dysfunction that can be uncoupled from T cell activation. This distinct dysfunction module is downstream of intracellular metallothioneins that regulate zinc metabolism and can be identified at single-cell resolution. We further identify Gata-3, a zinc-finger transcription factor in the dysfunctional module, as a regulator of dysfunction, and we use CRISPR-Cas9 genome editing to show that it drives a dysfunctional phenotype in CD8(+) TILs. Our results open novel avenues for targeting dysfunctional T cell states while leaving activation programs intact.

Low grandparental social support combined with low parental socioeconomic status is closely associated with obesity in preschool-aged children: a pilot study

While the influence of parental socioeconomic status (SES) on children's weight status is well known, the impact of other family-related aspects such as parental and grandparental social support is less understood. This study investigates the importance of parents' SES and social support (functional and structural) for weight status in a clinical sample of preschoolers 4-6 years old with obesity (n = 39, 56% girls; 73% of parents were overweight/obese, 50% were of non-Swedish origin). Linear regression analyses, simple and multiple, were performed on SES and social support with child BMI SDS (body mass index standard deviation score) as the dependent variable. The results show that parents' income and low emotional support from paternal grandparents were significantly associated with more severe obesity. The association between parental income and the child's BMI SDS was stronger among parents who had low emotional support from their own parents. In conclusion, grandparental social support may be protective against childhood obesity.

Olfactory loss after head and neck cancer radiation therapy

BACKGROUND

A reduced sense of smell may be one explanation for why patients with cancer in the ear, nose and throat (ENT) region who are treated with radiation therapy lose weight. The purpose of this study was to investigate whether radiation therapy has a negative effect on olfactory function and, if so, whether this effect is dose-related.

METHODOLOGY

Seventy-one patients were tested using odour-detection sensitivity and olfactory identification tests before radiation therapy and 20 months after it.

RESULTS

Patients who received radiation close to the olfactory organ showed a reduced sense of smell, in both tests. A multiple regression analysis showed that the radiation dose was related to decline in the olfactory function, while age, sex, chemotherapy and interactions between these variables were not.

CONCLUSION

Radiation therapy can damage olfactory cells.

Interobserver delineation variation in lung tumour stereotactic body radiotherapy

OBJECTIVES

In radiotherapy, delineation uncertainties are important as they contribute to systematic errors and can lead to geographical miss of the target. For margin computation, standard deviations (SDs) of all uncertainties must be included as SDs. The aim of this study was to quantify the interobserver delineation variation for stereotactic body radiotherapy (SBRT) of peripheral lung tumours using a cross-sectional study design.

METHODS

22 consecutive patients with 26 tumours were included. Positron emission tomography/CT scans were acquired for planning of SBRT. Three oncologists and three radiologists independently delineated the gross tumour volume. The interobserver variation was calculated as a mean of multiple SDs of distances to a reference contour, and calculated for the transversal plane (SD(trans)) and craniocaudal (CC) direction (SD(cc)) separately. Concordance indexes and volume deviations were also calculated.

RESULTS

Median tumour volume was 13.0 cm(3), ranging from 0.3 to 60.4 cm(3). The mean SD(trans) was 0.15 cm (SD 0.08 cm) and the overall mean SD(cc) was 0.26 cm (SD 0.15 cm). Tumours with pleural contact had a significantly larger SD(trans) than tumours surrounded by lung tissue.

CONCLUSIONS

The interobserver delineation variation was very small in this systematic cross-sectional analysis, although significantly larger in the CC direction than in the transversal plane, stressing that anisotropic margins should be applied. This study is the first to make a systematic cross-sectional analysis of delineation variation for peripheral lung tumours referred for SBRT, establishing the evidence that interobserver variation is very small for these tumours.

Combined stent insertion and single high-dose brachytherapy in patients with advanced esophageal cancer--results of a prospective safety study

Previous randomized studies comparing the two commonly used palliative treatments for incurable esophageal cancer, i.e. stent insertion and intraluminal brachytherapy, have revealed the pros and cons of each therapy. While stent treatment offers a more prompt effect, brachytherapy results in more long-lasting relief of dysphagia and a better health-related quality of life (HRQL) in those living longer. This prospective pilot study aimed to explore the feasibility and safety of combining these two regimes and incorporating a single high dose of internal radiation. Patients with newly diagnosed, incurable cancer of the esophagus and dysphagia were eligible for inclusion, and stent insertion followed by a single dose (12 Gy) of brachytherapy was performed as a two-stage procedure. Clinical parameters including HRQL and adverse events were registered at inclusion, and 1, 2, 3, 6, and 12 months later. Twelve patients (nine males) with a median age of 73 years (range 54-85) were included. Stent insertion followed by a single dose of brachytherapy was successfully performed in all but one patient who was treated with stent only. Relief of dysphagia was achieved in the majority of cases (10/11, P < 0.05), but HRQL did not improve except for dysphagia-related items. Only minor adverse events, including chest pain, reflux, and restenosis, were reported. The median survival time after inclusion was 6.6 months. Our conclusion is that the combination of stent insertion and single high-dose brachytherapy seems to be a feasible and safe palliative regime in patients with advanced esophageal cancer. Randomized trials comparing the efficacy of this strategy to stent insertion or brachytherapy alone are warranted.

Concurrent cetuximab and radiotherapy after docetaxel-cisplatin induction chemotherapy in stage III NSCLC: satellite--a phase II study from the Swedish Lung Cancer Study Group

BACKGROUND

Several attempts to increase the locoregional control in locally advanced lung cancer including concurrent chemotherapy, accelerated fractionation and dose escalation have been made during the last years. As the EGFR directed antibody cetuximab has shown activity concurrent with radiotherapy in squamous cell carcinoma of the head and neck, as well as in stage IV NSCLC combined with chemotherapy, we wanted to investigate radiotherapy with concurrent cetuximab in locally advanced NSCLC, a tumour type often over expressing the EGF-receptor.

METHODS

Between February 2006 and August 2007 75 patients in stage III NSCLC with good performance status (PS 0 or 1) and adequate lung function (FEV1>1.0) were enrolled in this phase II study at eight institutions. Treatment consisted of 2 cycles of induction chemotherapy, docetaxel 75 mg/m² and cisplatin 75 mg/m² with 3 weeks interval. An initial dose of cetuximab 400 mg/m² was given before start of 3D-CRT to 68 Gy with 2 Gy per fraction in 7 weeks concurrent with weekly cetuximab 250 mg/m². TOXICITY was scored weekly during radiotherapy (CTC 3.0), and after treatment the patients were followed every third month with CT-scans, toxicity scoring and QLQ.

RESULTS

Seventy-one patients were eligible for analysis as four were incorrectly enrolled.

HISTOLOGY

adenocarcinoma 49%, squamous cell carcinoma 39% and other NSCLC 12%. The majority had PS 0 (62.5%), median age 62.2 (42-81), 50% were women and 37% had a pre-treatment weight loss>5%.

TOXICITY

esophagitis grade 1-2: 72%; grade 3: 1.4%. Hypersensitivity reactions grade 3-4: 5.6%. Febrile neutropenia grade 3-4: 15.4%. Skin reactions grade 1-2: 74%; grade 3: 4.2%. Diarrhoea grade 1-2: 38%; grade 3: 11.3%. Pneumonitis grade 1-2: 26.8%; grade 3: 4.2%; grade 5: 1.4%. The median follow-up was 39 months for patients alive and the median survival was 17 months with a 1-, 2- and 3-year OS of 66%, 37% and 29% respectively. Until now local or regional failure has occurred in 20 patients and 22 patients have developed distant metastases. Weight loss, PS and stage were predictive for survival in univariate as well as in multivariate analysis.

CONCLUSION

Induction chemotherapy followed by concurrent cetuximab and RT to 68 Gy is clearly feasible with promising survival. TOXICITY, e.g. pneumonitis and esophagitis is low compared to most schedules with concurrent chemotherapy. This treatment strategy should be evaluated in a randomised manner vs. concurrent chemoradiotherapy to find out if it is a valid treatment option.

Does CO 2 flushing of the empty CPB circuit decrease the number of gaseous emboli in the prime?

Twenty (20) CPB-circuits were randomized to a CO2 group or a control group. In the CO 2 group, each circuit was flushed with CO2 (10L/min) at the top of the venous reservoir for 5 minutes, after which priming fluid was added without interruption of the CO2 inflow. Control group circuits were not flushed and contained air. A perfusionist, blinded to the study, started the pump (5L/min), ventilated the oxygenator (3L O2/min), and knocked on the oxygenator 20 times during the first and 14th minutes. Arterial line microemboli counts were registered with a Doppler for 15 minutes. In both groups, the median number of microemboli was highest during the first minute, 380.5 (288.75/422.25, 25th/75th percentile) counts in the control group versus 264.5 (171.75/422.25) counts in the CO 2 group (p=0.01). Throughout the experiment, the median microembolic count minute by minute in the CO2 group remained lower (p≤ 0 .004) than in the control group. Knocking on the reservoir (14th minute) increased the microemboli counts in both groups (p<0.01). The median values during the 15th minute were 15.5 and 0.5 in the control and the CO2 groups, respectively, which were 9% (15.5/173) and 0.5% (0.5/87), respectively, of the values registered after 14 minutes. In conclusion, CO 2 flushing of the empty circuit decreases the number of gaseous emboli in the prime compared with a conventional circuit that contains air before being primed with fluid. Knocking of the oxygenator releases gaseous emboli and the duration of re-circulating the circuit with prime influences the number of microemboli.

Upfront chemotherapy and accelerated radiotherapy with EGFR inhibition for locally advanced inoperable head and neck cancer

6040

Background: Concomitant chemoradiotherapy (CT/RT) is the standard treatment for locally advanced head and neck squamous cell carcinoma. However, late toxicity is substantial.This phase II trial explores the feasibility and efficacy of combining neoadjuvant TPF and accelerated RT where the concomitant cytostatic component is replaced with cetuximab (E), a chimeric IgG1 mAb against EGFR. Methods: Patients (pts) had previously untreated stage III/IV M0,WHO 0–1, unresectable squamous cell carcinoma of the oral cavity, oropharynx, larynx, or hypopharynx and were scheduled for 2 cycles of TPF (docetaxel 75 mg/m2 and cisplatin 75 mg/m2 day 1 and 5-FU 1,000 mg/m2 96 hours CI) every 3 weeks followed by RT (68 Gy/4.5 weeks) with E given one week before (400 mg/m2) and weekly during RT (250 mg/m2). A brachytherapy boost of 8 Gy was given to pts with oral cavity or oropharyngeal tumours. Neck dissection was planned for pts with N2–3 and complete response (CR) at the primary tumour. Tumour response was evaluated according to RECIST with CT, MRI or PET/CT after CT and at 6 weeks follow up. Toxicity (CTC 3.0) and quality of life (EORTC QLQ 30) was registered during and after treatment. Results: From 070401 to 081115 68 pts were enrolled, 56 had stage IV disease (T4, n = 14, N3, n = 9). Median age 57, 60 males, 3 oral cavity, 44 oropharynx, 10 larynx, and 11 hypopharynx. 30 pts were followed beyond 6 weeks and evaluated for response and early toxicity: stage IV disease 24 (T4, n = 6, N3, n = 3), median age 60, 25 males, 18 oropharynx, 5 larynx, and 7 hypopharynx. Remissions after TPF/after RT: CR 1/10, PR 15/18, SD 14/1, and PD 1. TPF as prescribed: 28/30 (pat refusal 1, renal insuff 1, dose reduction 0/28); E as prescribed: 22/30 (dermatitis 4, hypersensitivity 3, liver tox 1). Vital tumour in resected specimen 0/13. Alive at follow-up 29/30 (1 local failure). Conclusions: TPF followed by RT concomitant with E is feasible with manageable toxicities. Dermatitis in the irradiated neck, at least with the present accelerated fractionation, is troublesome to some patients but does not interrupt treatment and heals rapidly. To dispose of feeding tubes after disappearance of acute mucosal reactions has not been a problem. Early survival results are promising. Toxicity and survival results will be updated.

[Table: see text]

Locally delivered lovastatin nanoparticles enhance fracture healing in rats

Statins stimulate bone formation in vitro and in vivo and, when given in large doses or by prolonged infusions, stimulate biomechanical strength of murine long bones with healing fractures. However, administration of statins by large oral doses or prolonged infusions to a fracture site is not a feasible therapeutic approach to hasten healing of human fractures. We administered lovastatin in biodegradable polymer nanobeads of poly(lactic-co-glycolide acid) to determine if lovastatin delivered in low doses in nanoparticles of a therapeutically acceptable scaffold could increase rates of healing in a standard preclinical model of femoral fracture. We found that these nanobeads: (1) stimulated bone formation in vitro at 5 ng/mL, (2) increased rates of healing in femoral fractures when administered as a single injection into the fracture site, and (3) decreased cortical fracture gap at 4 weeks as assessed by microcomputed tomography. These preclinical results suggest that lovastatin administered in a nanobead preparation may be therapeutically useful in hastening repair of human fractures.

Stability in a denitrifying fluidized bed reactor

This study evaluates changes in the microbial community structure and function of a pilot-scale denitrifying fluidized bed reactor during periods of constant operating conditions and periods of perturbation. The perturbations consisted of a shutdown period without feed, two disturbances in which biofilms were mechanically sheared from carrier particles, and a twofold step increase in feed nitrate concentration. In the absence of perturbations, nitrate removal was stable and consistently greater than 99%. The structure and dynamics of the microbial community were studied using cloning and sequencing techniques and terminal restriction fragment length polymorphism (T-RFLP) of the SSU rRNA gene. Under unperturbed operating conditions, stable function was accompanied by high constancy and low variability of community structure with the majority of terminal restriction fragments (T-RFs) appearing throughout operation at consistent relative abundances. Several of the consistently present T-RFs correlated with clone sequences closely related to Acidovorax (98% similarity), Dechloromonas (99% similarity), and Zoogloea (98% similarity), genera recently identified by molecular analyses of similar systems. Significant changes in community structure and function were not observed after the shutdown period. In contrast, following the increase in loading rate and the mechanical disturbances, new T-RFs appeared. After both mechanical disturbances, function and community structure recovered. However, function was much more resilient than community structure. The similarity of response to the mechanical disturbances despite differences in community structure and operating conditions suggests that flexible community structure and potentially the activity of minor members under nonperturbation conditions promotes system recovery.

Radiotherapy vs. temozolomide in the treatment of patients with lung cancer and brain metastases: A nordic randomized phase II study

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Background: Metastasis to the brain is the most common intracranial tumour and 20–40% of all cancer patients will develop brain metastases. Lung cancer is the most common primary tumour and compose of 40%-50% of all brain metasases. As the survival in many malignancies increases, brain metastases will be an increasing problem. It is therefore important to find new treatment options. The aim of this study was primary to study quality of life and to compare radiotherapy and Themozolomide in that context. Methods: Inclusion criterias were confirmed small cell or non-small cell lung cancer, multiple brain metastases, PS 0–2, no previous radiotherapy to the brain. Previous chemotherapy was allowed. Patients were randomized to arm A (radiotherapy 30 Gy over 10 fractions) or arm B (Temozolomide 200 mg/m2 day 1–5, new cycle on day 29). Quality of life (QoL) was measured with a general cancer module, EORTC QLQ-C30, and a brain cancer specific module, BCM20. The primary end-point was the proportion of patients in each treatment arm with maintained or better QoL score at 8 weeks compared to the base line evaluation. In this first analysis exclusion rate from the study at 8 weeks was used as a surrogate end-point. Results: 208 patients were included, 104 in arm A and 104 in arm B. 36 (17%) squamous cell, 97 (47%) adenocarcinomas, 10 (5%) large cell, 23 (11%) undifferentiated and 42 (20%) small-cell lung cancer were included. 93 (45%) patients were chemonaive. At 8 weeks, 79 patients were excluded from the study, 51 (49%) from the temozolomide arm and 28 (27%) from the radiotherapy arm. 53% of the patients with squamous cell carcinoma were excluded compared to 40% of small cell lung cancer, 33% of adenocarcinomas and 27% of large cell carcinomas. The exclusion rate at 8 weeks was higher among patients with symptoms at randomization compared to patients without symptoms. There were no difference in exclusion rate when comparing number or size of the metastases. Conclusion: The exclusion rate at 8 weeks was higher in the temozolomide arm compared to the radiotherapy arm. Histopathology and symptoms at randomization seems to be factors influencing the exclusion rate whereas number or size of metastases does not. Survival and quality of life data will be presented at the meeting.

No significant financial relationships to disclose.

Stent insertion or endoluminal brachytherapy as palliation of patients with advanced cancer of the esophagus and gastroesophageal junction. Results of a randomized, controlled clinical trial

Esophageal cancer often presents as advanced stage disease with a dismal prognosis, with only 10-15% of patients surviving 5 years. Therefore, in a large proportion of patients, palliative treatment is the only option available. The aim of this study was to prospectively compare the palliative effect of self-expandable stent placement with that of endoluminal brachytherapy regarding the effect on quality of life and on specific symptoms. Sixty-five patients with advanced cancer of the esophagus or gastroesophageal junction were randomized to treatment with either an Ultraflex expandable stent or high-dose-rate endoluminal brachytherapy with 7 Gy x 3 given in 2-4 weeks. Clinical assessment and health-related quality of life (HRQL) were measured at inclusion and 1, 3, 6, 9 and 12 months later. The HRQL was measured with standardized questionnaires (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30, European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Oesophageal Module and Hospital Anxiety and Depression Scale). Twenty-eight patients completed the stent treatment and 24 patients the brachytherapy. The group of patients treated with stent reported significantly better HRQL scores for dysphagia (P < 0.05) at the 1-month follow-up, but most other HRQL scores, including functioning and symptom scales, deteriorated. Among brachytherapy-treated patients, improvement was found for the dysphagia-related scores at the 3-months follow-up, whereas other significant changes of scores were few. The median survival time was comparable in the two groups (around 120 days). In conclusion, insertion of self-expandable metal stents offered a more instant relief of dysphagia compared to endoluminal brachytherapy, but HRQL was more stable in the brachytherapy group.

Time factor for acute tissue reactions following fractionated irradiation: a balance between repopulation and enhanced radiosensitivity

Experimental data for acute radiation-induced skin reactions are reviewed. These show that for dose fractionation schedules with gaps, repopulation is initiated after a lag period. After this lag period, the isoeffective dose for a given level of skin reaction first increases rapidly, but then slows. The timing of the lag period is related to the total turnover time of the tissue under investigation and, for example, is shorter in rodent skin than in pig or human skin. At the point when accelerated repopulation is initiated, there is a major shortening of the turnover time of the target cell population. At this time, there is evidence, for a short period, for an increase in radiosensitivity of the surviving stem cells in a number of acutely responding normal tissues. This effect is clearly illustrated by the results of experiments using sequential dose fractionation schedules. Prolongation of the schedule from 'short' to schedules that include irradiation over the period when the cell turnover is accelerated is associated with a marked increase in tissue radiosensitivity. Clinically, this is best illustrated by a comparison of the effects of accelerated fractionation schedules, involving multiple fractions/day, with daily fractionation schedules. The increase in radiosensitivity produced by the prolongation of the treatment from 2 to 4-5 weeks was equivalent to > or =1 Gy day(-1). Comparable findings were obtained from animal studies. In the oral mucosa of mice, the initiation of accelerated cell proliferation in surviving cells is associated with the loss of dose sparing by subsequent dose fractionation due to the loss of the capacity to repair sublethal damage. Studies in pig and human skin have indicated that increased radiosensitivity is associated with a loss of cells in the G1 phase of the cell cycle. A collation of these two sets of findings suggests that the repair of sublethal damage takes place over this phase of the cell cycle. One clinical implication of these findings is that the alpha/beta ratio for acute skin reaction changes with the length of the overall treatment time; it is approximately 4.0 Gy for 'short' fractionation schedules that avoid any shortening of the cell cycle time. This increases to 11.2-13.3 Gy for schedules given in 3-4 weeks and to approximately 35 Gy for schedules given in 5-6 weeks. Results for pig skin were in total agreement with those for human skin.

Normal tissue response to low doses of radiotherapy assessed by molecular markers--a study of skin in patients treated for prostate cancer

The aim of this study was to evaluate normal tissue response by molecular markers to multifraction low doses of ionizing radiation, with the focus on changes in repopulation, estimated using Ki-67 as the proliferation marker, and on expressions of the p53 and p21 proteins, identified as key proteins in the DNA damage checkpoint. Repeated skin biopsies were taken from patients treated for prostate cancer with radiotherapy. The expressions of Ki-67, p53 and p21 of the keratinocytes in the basal cell layer of the epidermis were quantified immunohistochemically. The dose to the basal layer was 1.1 Gy per fraction, given five times per week for seven weeks. The indices of the three markers were determined over the whole period. A significant suppression of the Ki-67 index was observed during the first weeks, followed by a significant gradual increase in the Ki-67 index over the last weeks. The p53 and p21 protein levels were almost zero in the unirradiated skin. Upon irradiation, both the p53 and p21 index increased in a pattern very congruent to the Ki-67 index. In conclusion, daily fractions of about 1 Gy to the skin resulted in, for the keratinocytes in the basal layer, a cell growth arrest for a couple of weeks and a subsequent acceleration in repopulation during the following weeks of irradiation. The present findings also provided novel insights into the role of the p53/p21 pathway in the response of a normal epithelium to ionizing radiation as it is applied in radiotherapy.

Accuracy of tele-oncology compared with face-to-face consultation in head and neck cancer case conferences

Telemedicine was introduced for weekly tumour case conferences between Sahlgrenska University Hospital and two district hospitals in Sweden. The accuracy of tele-oncology was determined using simulated telemedicine consultations, in which all the material relating to each case was presented but without the patient in person. The people attending the conference were asked to determine the tumour ('TNM') classification and treatment. The patient was then presented in person, to give the audience the opportunity to ask questions and perform a physical examination. Then a new discussion regarding the tumour classification and the treatment plan took place, and the consensus was recorded. Of the 98 consecutive patients studied in this way, 80 could be evaluated by both techniques. Of these 80, 73 (91%) had the same classification and treatment plan in the telemedicine simulation as in the subsequent face-to-face consultation. In four cases the TNM classification was changed and for three patients the treatment plan was altered. The specialists also had to state their degree of confidence in the tele-oncology decisions. When they recorded uncertainty about their decision, it was generally because they wanted to palpate the tumour. In five of the seven patients with a different outcome, the clinical evaluation was stated to be dubious or not possible. The results show that telemedicine can be used safely for the management of head and neck cancers.

Cardiopulmonary resuscitation skills in nurses and nursing students

The purpose of this study is to describe the basic cardiac life-support (BLS) skills of nurses and nursing students in southern Finland and Hungary, and to assess the influence of resuscitation teaching and other group characteristics on performance. The data for the study were collected in the spring and autumn of 1997. The study group consisted of 75 nurses from Helsinki University Central Hospital's medical outcome unit, 188 final term students in four nursing institutes in Uusimaa county and 35 final term students in a Hungarian institute of nursing. A total of 298 people (34 men and 264 women) participated in the study. Background information was collected using a structured questionnaire devised specifically for this study. Resuscitation skills were measured using the Skillmeter Anne manikin. The manikin was placed supine during the test. After completing the questionnaire, every participant attempted resuscitation on the manikin - which was supplied with a printer - for 4 min. The results were printed out and attached to the questionnaires. The data were analysed using two-way frequency tables and logistic regression. Statistical differences were calculated using the chi(2)-test. The results showed that 53% of the participants had studied resuscitation during the last 6 months, but 7% had never participated in resuscitation teaching. Before testing, 55% of the participants estimated that their resuscitation skills were good. The results showed that 36% first assessed the patient's response, 67% opened the airway but only 3% determined pulselessness before starting to resuscitate. Twenty-one percent of the participants compressed correctly for at least half of the test and 33% ventilated correctly at least half of the time. Logistic regression showed that the best predictors for good response assessment skills went to those who were nursing students who had studied resuscitation skills sometime during the previous 6 months. The best predictor of the skill to open the airway was a positive attitude towards personal cardiopulmonary resuscitation (CPR) skills, i.e. self-confidence. The predictor for adequate skills in artificial ventilation was that they belonged in the group of nursing students who had benefited from recent resuscitation training (<6 months). In conclusion, the skills of the participants of the study can not be considered adequate in terms of an adequate and prompt assessment of the need for resuscitation, and a 50% success rate in artificial ventilation and chest compression.

The cost of work-related physical assaults in Minnesota

OBJECTIVE

To describe the long-term productivity costs of occupational assaults.

DATA SOURCES/STUDY SETTING

All incidents of physical assaults that resulted in indemnity payments, identified from the Minnesota Department of Labor and Industry (DLI) Workers' Compensation system in 1992. Medical expenditures were obtained from insurers, and data on lost wages, legal fees, and permanency ratings were collected from DLI records. Insurance administrative expenses were estimated. Lost fringe benefits and household production losses were imputed.

STUDY DESIGN

The human capital approach was used to describe the long-term costs of occupational assaults. Economic software was used to apply a modified version of Rice, MacKenzie, and Associates' (1989) model for estimating the present value of past losses from 1992 through 1995 for all cases, and the future losses for cases open in 1996.

PRINCIPAL FINDINGS

The total costs for 344 nonfatal work-related assaults were estimated at $5,885,448 (1996 dollars). Calculation of injury incidence and average costs per case and per employee identified populations with an elevated risk of assault. An analysis by industry revealed an elevated risk for workers employed in justice and safety (incidence: 198/100,000; $19,251 per case; $38 per employee), social service (incidence: 127/100,000; $24,210 per case; $31 per employee), and health care (incidence: 76/100,000; $13,197 per case; $10 per employee).

CONCLUSIONS

Identified subgroups warrant attention for risk factor identification and prevention efforts. Cost estimates can serve as the basis for business calculations on the potential value of risk management interventions.

Comparison of DNA repair protein expression and activities between human fibroblast cell lines with different radiosensitivities

In order to investigate the molecular basis of variation in response to ionising radiation (IR) in radiotherapy patients, we have studied the expression of several genes involved in DNA double-strand break repair pathways in fibroblast cell lines. Ten lines were established from skin biopsies of cancer patients with different normal-tissue reactions to IR, and 3 from a control individual. For all 10 test cell lines, the cellular radiosensitivity was also known. Using Western blots we measured, in non-irradiated cells, the basal expression levels of ATM, Rad1 and Hus1, involved in the control of cellular DNA damage checkpoints, together with DNA-PKcs, Ku70, Ku80; XRCC4, ligaseIV and Rad51, involved in radiation- induced DSB repair. We also analysed the in vitro enzymatic activities, under non-irradiated conditions, of the DNA-PK and XRCC4/ligaseIV complexes. The levels of expression of the different proteins were similar in all the cell lines, but the activities of the DNA-PK and XRCC4/ligaseIV complexes showed some differences. These differences did not correlate with either the normal tissue response of the patient in vivo or with cellular radiation sensitivity in vitro. The activity differences of these enzyme complexes, therefore, do not account for the variation of responses seen between patients.

Comparison of DNA repair protein expression and activities between human fibroblast cell lines with different radiosensitivities

In order to investigate the molecular basis of variation in response to ionising radiation (IR) in radiotherapy patients, we have studied the expression of several genes involved in DNA double-strand break repair pathways in fibroblast cell lines. Ten lines were established from skin biopsies of cancer patients with different normal-tissue reactions to IR, and 3 from a control individual. For all 10 test cell lines, the cellular radiosensitivity was also known. Using Western blots we measured, in non-irradiated cells, the basal expression levels of ATM, Rad1 and Hus1, involved in the control of cellular DNA damage checkpoints, together with DNA-PKcs, Ku70, Ku80; XRCC4, ligaseIV and Rad51, involved in radiation- induced DSB repair. We also analysed the in vitro enzymatic activities, under non-irradiated conditions, of the DNA-PK and XRCC4/ligaseIV complexes. The levels of expression of the different proteins were similar in all the cell lines, but the activities of the DNA-PK and XRCC4/ligaseIV complexes showed some differences. These differences did not correlate with either the normal tissue response of the patient in vivo or with cellular radiation sensitivity in vitro. The activity differences of these enzyme complexes, therefore, do not account for the variation of responses seen between patients.

Accelerated hyperfractionated radiotherapy combined with induction and concomitant chemotherapy for inoperable non-small-cell lung cancer--impact of total treatment time

Tumour cell proliferation during conventionally fractionated radiotherapy (RT) can negatively influence the treatment outcome in patients with unresectable non-small-cell lung cancer (NSCLC). Accelerated and hyperfractionated RT may therefore have an advantage over conventional RT. Moreover, earlier studies have suggested improved survival with addition of cisplatin-based chemotherapy (CT). We present here the results of combined treatment with induction and concomitant CT and accelerated hyperfractionated RT in a retrospective series of patients with advanced NSCLC. Between August 1990 and August 1995, 90 consecutive patients, aged 42-77 years (median 63 years), with locally advanced unresectable or medically inoperable NSCLC and good performance status were referred for treatment: stage: I 23%, IIIa 37%, IIIb 40%. Patient histologies included: squamous cell carcinoma 52%, adenocarcinoma 34% and large cell carcinoma 13%. The treatment consisted of two courses of CT (cisplatin 100 mg/m2 day 1 and etoposide 100 mg/m2 day 1-3 i.v.), the second course given concomitantly with RT. The total RT dose was 61.2-64.6 Gy, with two daily fractions of 1.7 Gy. A one-week interval was introduced after 40.8 Gy to reduce acute toxicity, making the total treatment time 4.5 weeks. Concerning toxicity, 33 patients had febrile neutropenia, 10 patients suffered from grade III oesophagitis and 7 patients had grade III pneumonitis. There were two possible treatment-related deaths, one due to myocardial infarction and the other due to a pneumocystis carinii infection. The 1-, 2- and 3-year overall survival rates were 72%, 46% and 34%, respectively; median survival was 21.3 months. Fifty-nine patients had progressive disease: 21 failed locoregionally, 29 had distant metastases and 9 patients had a combination of these. Pretreatment weight loss was the only prognostic factor found, except for stage. However, the results for stage IIIb were no different from those for stage IIIa. We conclude that the survival results compare favourably with those of most other studies with a manageable toxicity.