Immune microenvironment in mesothelioma: Looking beyond PD-L1

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Background: Studies using immune checkpoint inhibitors in mesothelioma (MM) have shown promise. Differences in response to PD-L1 and PD-1 inhibitors (10% vs 25%) have been reported. Also, expression of PD-L1 alone appears to be a limited predictor. As the roles of the multiple check point receptors and their ligands become defined, an understanding of their expression and interplay in the mm tumour microenvironment, which could affect suitability for checkpoint inhibition therapy, has become necessary. Methods: Tissue microarrays were constructed and stained with PD-L2, LAG3 and TIM3 antibodies. Tumour infiltrating lymphocytes (TILs) were assessed in the stroma and expressed as a % of stromal area within invasive tumour. These data were combined with PD-L1 expression, CD4+ and CD8+ infiltration in the same cohort reported previously. To quantify the immunosuppressive milieu, we combined our assessment of PD-L1, PD-L2 and TIM3 expression to derive an “Immune checkpoint score (ICS)” and explored its correlation with the tumour microenvironment and clinicopathological covariates. We are also exploring its predictive value in an independent cohort of mm patients who have received anti-PD-1 treatment. Results: Amongst 329 patients evaluated, PD-L1 was positive (+) in 41.7% and PD-L2+ in 24.5%. TIM3+ lymphocytes were found in 99.4% but LAG3+ lymphocytes in only 0.2%. 28/173 (16%) of PD-L1- patients were PD-L2+ and 31/136 (22%) PD-L1 and PD-L2 negative patients had high infiltration with TIM3+ lymphocytes. High ICS was associated with non-epithelioid histology, increased TILs and poorer survival. On multivariate analysis, high TILs, non-epithelioid histology and poor physiological status remained significantly associated with poorer survival. Data on the predictive role of ICS score will also be reported. Conclusions: While co-expression of PD-L1, PD-L2 and TIM3 can occur, their expression is mutually exclusive in a large proportion of patients. The expression of PD-L2 may explain differences in responses seen between PD-1 compared to PD-L1 inhibitors. A comprehensive assessment of these multiple immunosuppressive pathways may be necessary to truly gauge the immunosuppressive environment and tailor immunotherapy for individual cases.

Intra- and Interobserver Reproducibility Assessment of PD-L1 Biomarker in Non-Small Cell Lung Cancer

Purpose: Reliable and reproducible methods for identifying PD-L1 expression on tumor cells are necessary to identify responders to anti-PD-1 therapy. We tested the reproducibility of the assessment of PD-L1 expression in non-small cell lung cancer (NSCLC) tissue samples by pathologists.Experimental Design: NSCLC samples were stained with PD-L1 22C3 pharmDx kit using the Dako Autostainer Link 48 Platform. Two sample sets of 60 samples each were designed to assess inter- and intraobserver reproducibility considering two cut points for positivity: 1% or 50% of PD-L1 stained tumor cells. A randomization process was used to obtain equal distribution of PD-L1 positive and negative samples within each sample set. Ten pathologists were randomly assigned to two subgroups. Subgroup 1 analyzed all samples on two consecutive days. Subgroup 2 performed the same assessments, except they received a 1-hour training session prior to the second assessment.Results: For intraobserver reproducibility, the overall percent agreement (OPA) was 89.7% [95% confidence interval (CI), 85.7-92.6] for the 1% cut point and 91.3% (95% CI, 87.6-94.0) for the 50% cut point. For interobserver reproducibility, OPA was 84.2% (95% CI, 82.8-85.5) for the 1% cut point and 81.9% (95% CI, 80.4-83.3) for the 50% cut point, and Cohen's κ coefficients were 0.68 (95% CI, 0.65-0.71) and 0.58 (95% CI, 0.55-0.62), respectively. The training was found to have no or very little impact on intra- or interobserver reproducibility.Conclusions: Pathologists reported good reproducibility at both 1% and 50% cut points. More adapted training could potentially increase reliability, in particular for samples with PD-L1 proportion, scores around 50%. Clin Cancer Res; 23(16); 4569-77. ©2017 AACR.

The Use of Immunohistochemistry Improves the Diagnosis of Small Cell Lung Cancer and Its Differential Diagnosis. An International Reproducibility Study in a Demanding Set of Cases

INTRODUCTION

The current WHO classification of lung cancer states that a diagnosis of SCLC can be reliably made on routine histological and cytological grounds but immunohistochemistry (IHC) may be required, particularly (1) in cases in which histologic features are equivocal and (2) in cases in which the pathologist wants to increase confidence in diagnosis. However, reproducibility studies based on hematoxylin and eosin-stained slides alone for SCLC versus large cell neuroendocrine carcinoma (LCNEC) have shown pairwise κ scores ranging from 0.35 to 0.81. This study examines whether judicious use of IHC improves diagnostic reproducibility for SCLC.

METHODS

Nineteen lung pathologists studied interactive digital images of 79 tumors, predominantly neuroendocrine lung tumors. Images of resection and biopsy specimens were used to make diagnoses solely on the basis of morphologic features (level 1), morphologic features along with requested IHC staining results (level 2), and all available IHC staining results (level 3).

RESULTS

For the 19 pathologists reading all 79 cases, the rate of agreement for level 1 was 64.7%, and it increased to 73.2% and 77.5% in levels 2 and 3, respectively. With IHC, κ scores for four tumor categories (SCLC, LCNEC, carcinoid tumors, and other) increased in resection samples from 0.43 to 0.60 and in biopsy specimens from 0.43 to 0.64.

CONCLUSIONS

Diagnosis using hematoxylin and eosin staining alone showeds moderate agreement among pathologists in tumors with neuroendocrine morphology, but agreement improved to good in most cases with the judicious use of IHC, especially in the diagnosis of SCLC. An approach for IHC in the differential diagnosis of SCLC is provided.

Impact of sex on prognostic host factors in surgical patients with lung cancer

BACKGROUND

Lung cancer has markedly poorer survival in men. Recognized important prognostic factors are divided into host, tumour and environmental factors. Traditional staging systems that use only tumour factors to predict prognosis are of limited accuracy. By examining sex-based patterns of disease-specific survival in non-small cell lung cancer patients, we determined the effect of sex on the prognostic value of additional host factors.

METHODS

Two cohorts of patients treated surgically with curative intent between 2000 and 2009 were utilized. The primary cohort was from Melbourne, Australia, with an independent validation set from the American Surveillance, Epidemiology and End Results (SEER) database. Univariate and multivariate analyses of validated host-related prognostic factors were performed in both cohorts to investigate the differences in survival between men and women.

RESULTS

The Melbourne cohort had 605 patients (61% men) and SEER cohort comprised 55 681 patients (51% men). Disease-specific 5-year survival showed men had statistically significant poorer survival in both cohorts (P < 0.001); Melbourne men at 53.2% compared with women at 68.3%, and SEER 53.3% men and 62.0% women were alive at 5 years. Being male was independently prognostic for disease-specific mortality in the Melbourne cohort after adjustment for ethnicity, smoking history, performance status, age, pathological stage and histology (hazard ratio = 1.54, 95% confidence interval: 1.10-2.16, P = 0.012).

CONCLUSIONS

Sex differences in non-small cell lung cancer are important irrespective of age, ethnicity, smoking, performance status and tumour, node and metastasis stage. Epidemiological findings such as these should be translated into research and clinical paradigms to determine the factors that influence the survival disadvantage experienced by men.

IL6 Trans-signaling Promotes KRAS-Driven Lung Carcinogenesis

Oncogenic KRAS mutations occur frequently in lung adenocarcinoma. The signaling pathways activated by IL6 promote Kras-driven lung tumorigenesis, but the basis for this cooperation is uncertain. In this study, we used the gp130(F/F) (Il6st) knock-in mouse model to examine the pathogenic contribution of hyperactivation of the STAT3 arm of IL6 signaling on KRAS-driven lung tumorigenesis. Malignant growths in the gp130(F/F):Kras(G12D) model displayed features of atypical adenomatous hyperplasia, adenocarcinoma in situ, and invasive adenocarcinoma throughout the lung, as compared with parental Kras(G12D) mice, where STAT3 was not hyperactivated. Among IL6 family cytokines, only IL6 was upregulated in the lung. Accordingly, normalization of pulmonary STAT3 activity, by genetic ablation of either Il6 or Stat3, suppressed the extent of lung cancer in the model. Mechanistic investigations revealed elevation in the lung of soluble IL6 receptor (sIL6R), the key driver of IL6 trans-signaling, and blocking this mechanism via interventions with an anti-IL6R antibody or the inhibitor sgp130Fc ameliorated lung cancer pathogenesis. Clinically, expression of IL6 and sIL6R was increased significantly in human specimens of lung adenocarcinoma or patient serum. Our results offer a preclinical rationale to clinically evaluate IL6 trans-signaling as a therapeutic target for the treatment of KRAS-driven lung adenocarcinoma.

Associations between the IASLC/ATS/ERS lung adenocarcinoma classification and EGFR and KRAS mutations

We sought to investigate the frequency of mutations in epidermal growth factor receptor (EGFR) and Kirsten-RAS (KRAS) by each pathological subtype for patients with resected pulmonary adenocarcinoma as defined by the IASLC/ATS/ERS classification. Histological examination determined the predominant subtype according to the IASLC/ATS/ERS classification. EGFR and KRAS mutations were determined by high-resolution melting and Sanger sequencing. Clinical data were collected from medical records and clinicians. The 178 consecutive patients consisted of 48% males, median age 68 years (range 20-87) and smoking history 78%. The tumour stage was I in 62%, II in 18% and III in 20%. The mutation rates were: EGFR 30%; KRAS 28%. The rate of EGFR mutations in the acinar predominant reference group (n=76), was 37%. The solid predominant subtype showed significantly fewer EGFR mutations [3/33 (9%), odds ratio 0.17 (0.05-0.61), p=0.007]. No differences in mutation rate were observed in other subtypes. No association was found between KRAS mutations and predominant histological subtype. Advanced stage and solid predominant subtype were negative prognostic factors. EGFR mutations can be present in adenocarcinoma of any predominant subtype, however rarely in solid predominant tumours. No association was found between KRAS mutation and the predominant histological subtype.

Differential expression of immunohistochemical markers in primary lung and breast cancers enriched for triple-negative tumours

AIMS

In breast cancer patients presenting with a lung lesion, the distinction between lung and breast origin is clinically important. Lung and breast cancers are both CK7(+) /CK20(-) , so additional immunohistochemical markers are needed.

METHODS AND RESULTS

We examined the expression of oestrogen receptor (ER), progesterone receptor (PR), thyroid transcription factor-1 (TTF-1), gross cystic disease fluid protein-15 (GCDFP-15), p63 and Wilms' tumour 1 (WT1) in a series of tissue microarrays comprising 266 non-small-cell lung cancers and 837 primary breast cancers enriched for triple-negative tumours (TNBC). Staining for ER, PR, TTF-1 and GCDFP-15 was present in 63%, 49%, 0% and 25% of breast and 6%, 9%, 59% and 1% of lung cancers, respectively. Strong staining for p63 was present in 63 (97%) lung squamous cell carcinomas and only eight (9%) TNBC. WT1 nuclear staining was rare; however, cytoplasmic staining was identified in 49 (40%) TNBC and 10 (5%) lung cancers. Cluster analysis segregated TNBC from lung cancers with TTF-1 and/or p63 staining favouring lung origin, and GCDFP-15 or WT1 staining favouring breast origin. Cancers negative for all four markers (17%) were 60% breast and 40% lung origin.

CONCLUSION

An immunohistochemical panel incorporating ER, TTF-1, GCDFP-15, p63 and WT1 can help to distinguish lung cancer from metastatic breast cancer, including TNBC.

Comprehensive genomic profiles of small cell lung cancer

We have sequenced the genomes of 110 small cell lung cancers (SCLC), one of the deadliest human cancers. In nearly all the tumours analysed we found bi-allelic inactivation of TP53 and RB1, sometimes by complex genomic rearrangements. Two tumours with wild-type RB1 had evidence of chromothripsis leading to overexpression of cyclin D1 (encoded by the CCND1 gene), revealing an alternative mechanism of Rb1 deregulation. Thus, loss of the tumour suppressors TP53 and RB1 is obligatory in SCLC. We discovered somatic genomic rearrangements of TP73 that create an oncogenic version of this gene, TP73Δex2/3. In rare cases, SCLC tumours exhibited kinase gene mutations, providing a possible therapeutic opportunity for individual patients. Finally, we observed inactivating mutations in NOTCH family genes in 25% of human SCLC. Accordingly, activation of Notch signalling in a pre-clinical SCLC mouse model strikingly reduced the number of tumours and extended the survival of the mutant mice. Furthermore, neuroendocrine gene expression was abrogated by Notch activity in SCLC cells. This first comprehensive study of somatic genome alterations in SCLC uncovers several key biological processes and identifies candidate therapeutic targets in this highly lethal form of cancer.

Identification of novel fusion genes in lung cancer using breakpoint assembly of transcriptome sequencing data

Genomic translocation events frequently underlie cancer development through generation of gene fusions with oncogenic properties. Identification of such fusion transcripts by transcriptome sequencing might help to discover new potential therapeutic targets. We developed TRUP (Tumor-specimen suited RNA-seq Unified Pipeline) (https://github.com/ruping/TRUP), a computational approach that combines split-read and read-pair analysis with de novo assembly for the identification of chimeric transcripts in cancer specimens. We apply TRUP to RNA-seq data of different tumor types, and find it to be more sensitive than alternative tools in detecting chimeric transcripts, such as secondary rearrangements in EML4-ALK-positive lung tumors, or recurrent inactivating rearrangements affecting RASSF8.

Mapping of actionable mutations to histological subtype domains in lung adenocarcinoma: implications for precision medicine

Precision medicine depends on the accurate identification of actionable mutations in a tumor sample. It is unknown how heterogeneous the distribution of such mutations can be in a tumor. Morphological (i.e. histopathological) heterogeneity is well described in lung adenocarcinoma and has been specifically recognized in the most recent official clinico-pathological classification. The most predominant subtype present is now used to classify each lung adenocarcinoma. No molecular profile exists to explain the intratumoral differences in lung adenocarcinoma morphology, despite the consistently observed association between specific predominant subtypes and poorer survival. Given a recent proposal stratifying lung adenocarcinoma into subtypes of differing metastatic potential, we questioned the assumption that major mutations are present uniformly throughout tumors; especially those showing discrete different subtypes.

We selected formalin-fixed paraffin embedded lung adenocarcinoma specimens that showed discrete areas of different subtypes, extracted subtype DNA samples from those areas and screened for mutations in hotspot regions of the EGFR, KRAS and BRAF genes using high resolution melting. Sanger sequencing was used to confirm all identified mutations. Chromogenic in situ hybridization (CISH) was used to identify mutant allele specific imbalances in tumors with EGFR mutations.

Interestingly, we found that KRAS and BRAF mutations could be confined to morphological domains of higher grade. On the other hand, EGFR mutations were found through all histological subtypes in each tumor consistent with the driver status of this mutation.

Intratumoral heterogeneity has major implications for tumorigenesis, chemoresistance and the role of histopathology in molecular screening for precision medicine. This study not only confirms that intratumoral mutational heterogeneity does occur, but also that it is associated with morphologically distinct regions in some tumors. From a practical perspective, small biopsies may not adequately represent a tumor's full mutational profile, particularly for later arising but prognostically important mutations such as those in the KRAS and BRAF genes.

Genomic characterisation of small cell lung cancer patient-derived xenografts generated from endobronchial ultrasound-guided transbronchial needle aspiration specimens

Patient-derived xenograft (PDX) models generated from surgical specimens are gaining popularity as preclinical models of cancer. However, establishment of PDX lines from small cell lung cancer (SCLC) patients is difficult due to very limited amount of available biopsy material. We asked whether SCLC cells obtained from endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) could generate PDX lines that maintained the phenotypic and genetic characteristics of the primary tumor. Following successful EBUS-TBNA sampling for diagnostic purposes, we obtained an extra sample for cytologic analysis and implantation into the flanks of immunodeficient mice. Animals were monitored for engraftment for up to 6 months. Histopathologic and immunohistochemical analysis, and targeted next-generation re-sequencing, were then performed in both the primary sample and the derivative PDX line. A total of 12 patients were enrolled in the study. EBUS-TBNA aspirates yielded large numbers of viable tumor cells sufficient to inject between 18,750 and 1,487,000 cells per flank, and to yield microgram quantities of high-quality DNA. Of these, samples from 10 patients generated xenografts (engraftment rate 83%) with a mean latency of 104 days (range 63–188). All but one maintained a typical SCLC phenotype that closely matched the original sample. Identical mutations that are characteristic of SCLC were identified in both the primary sample and xenograft line. EBUS-TBNA has the potential to be a powerful tool in the development of new targeting strategies for SCLC patients by providing large numbers of viable tumor cells suitable for both xenografting and complex genomic analysis.

Rationale for co-targeting IGF-1R and ALK in ALK fusion-positive lung cancer

Crizotinib, a selective tyrosine kinase inhibitor (TKI), shows marked activity in patients whose lung cancers harbor fusions in the gene encoding anaplastic lymphoma receptor tyrosine kinase (ALK), but its efficacy is limited by variable primary responses and acquired resistance. In work arising from the clinical observation of a patient with ALK fusion-positive lung cancer who had an exceptional response to an insulin-like growth factor 1 receptor (IGF-1R)-specific antibody, we define a therapeutic synergism between ALK and IGF-1R inhibitors. Similar to IGF-1R, ALK fusion proteins bind to the adaptor insulin receptor substrate 1 (IRS-1), and IRS-1 knockdown enhances the antitumor effects of ALK inhibitors. In models of ALK TKI resistance, the IGF-1R pathway is activated, and combined ALK and IGF-1R inhibition improves therapeutic efficacy. Consistent with this finding, the levels of IGF-1R and IRS-1 are increased in biopsy samples from patients progressing on crizotinib monotherapy. Collectively these data support a role for the IGF-1R-IRS-1 pathway in both ALK TKI-sensitive and ALK TKI-resistant states and provide a biological rationale for further clinical development of dual ALK and IGF-1R inhibitors.

CD74-NRG1 fusions in lung adenocarcinoma

We discovered a novel somatic gene fusion, CD74-NRG1, by transcriptome sequencing of 25 lung adenocarcinomas of never smokers. By screening 102 lung adenocarcinomas negative for known oncogenic alterations, we found four additional fusion-positive tumors, all of which were of the invasive mucinous subtype. Mechanistically, CD74-NRG1 leads to extracellular expression of the EGF-like domain of NRG1 III-β3, thereby providing the ligand for ERBB2-ERBB3 receptor complexes. Accordingly, ERBB2 and ERBB3 expression was high in the index case, and expression of phospho-ERBB3 was specifically found in tumors bearing the fusion (P < 0.0001). Ectopic expression of CD74-NRG1 in lung cancer cell lines expressing ERBB2 and ERBB3 activated ERBB3 and the PI3K-AKT pathway, and led to increased colony formation in soft agar. Thus, CD74-NRG1 gene fusions are activating genomic alterations in invasive mucinous adenocarcinomas and may offer a therapeutic opportunity for a lung tumor subtype with, so far, no effective treatment.

SIGNIFICANCE

CD74–NRG1 fusions may represent a therapeutic opportunity for invasive mucinous lung adenocarcinomas, a tumor with no effective treatment that frequently presents with multifocal unresectable disease.

Mobilization of viable tumor cells into the circulation during radiation therapy

PURPOSE

To determine whether radiation therapy (RT) could mobilize viable tumor cells into the circulation of non-small cell lung cancer (NSCLC) patients.

METHODS AND MATERIALS

We enumerated circulating tumor cells (CTCs) by fluorescence microscopy of blood samples immunostained with conventional CTC markers. We measured their DNA damage levels using γ-H2AX, a biomarker for radiation-induced DNA double-strand breaks, either by fluorescence-activated cell sorting or by immunofluorescence microscopy.

RESULTS

Twenty-seven RT-treated NSCLC patients had blood samples analyzed by 1 or more methods. We identified increased CTC numbers after commencement of RT in 7 of 9 patients treated with palliative RT, and in 4 of 8 patients treated with curative-intent RT. Circulating tumor cells were also identified, singly and in clumps in large numbers, during RT by cytopathologic examination (in all 5 cases studied). Elevated γ-H2AX signal in post-RT blood samples signified the presence of CTCs derived from irradiated tumors. Blood taken after the commencement of RT contained tumor cells that proliferated extensively in vitro (in all 6 cases studied). Circulating tumor cells formed γ-H2AX foci in response to ex vivo irradiation, providing further evidence of their viability.

CONCLUSIONS

Our findings provide a rationale for the development of strategies to reduce the concentration of viable CTCs by modulating RT fractionation or by coadministering systemic therapies.

Testing for ALK rearrangement in lung adenocarcinoma: a multicenter comparison of immunohistochemistry and fluorescent in situ hybridization

Rearrangements of anaplastic lymphoma kinase (ALK) gene in non-small cell lung cancer (NSCLC) define a molecular subgroup of tumors characterized clinically by sensitivity to ALK tyrosine kinase inhibitors such as crizotinib. Although ALK rearrangements may be detected by reverse transcriptase-PCR, immunohistochemistry or fluorescence in situ hybridization (FISH), the optimal clinical strategy for identifying ALK rearrangements in clinical samples remains to be determined. We evaluated immunohistochemistry using three different antibodies (ALK1, 5A4 and D5F3 clones) to detect ALK rearrangements and compared those with FISH. We report the frequency and clinicopathologic features of lung cancers harboring ALK translocations in 594 resected NSCLCs (470 adenocarcinomas; 83 squamous carcinomas, 26 large cell carcinomas and 15 other histological subtypes) using a tissue microarray approach. We identified an ALK gene rearrangement in 7/594 cases (1%) by FISH and all anti-ALK antibodies correctly identified the seven ALK-positive cases (100% sensitivity), although the intensity of staining was weak in some cases. These data indicate that the use of antibodies with high sensitivity and avidity to ALK may provide an effective pre-screening technique to complement the more expensive and labor-intensive approach of ALK FISH testing.

Overexpression of CD39 protects in a mouse model of preeclampsia

CD39 (NTPDase1), a critical immune and vascular ecto-nucleotidase, hydrolyses pro-inflammatory and pro-thrombotic nucleotides (adenosine-5'-triphosphate (ATP) and adenosine diphosphate) to adenosine. In humans, CD39 is the dominant ecto-nucleotidase in placental trophoblastic tissues and modulates ATP-dependent trophoblastic functions. CD39 is an integral component of regulatory T cells (Treg), which are central to immunological tolerance and maintenance of normal pregnancy. We examined the impact of CD39 overexpression in a mouse model of preeclampsia. Matings were performed between virginal BALB/c female (wild-type (WT) or CD39 transgenic (CD39TG)) and C57BL/6 male mice. On days 10 and 12 of pregnancy BALB/c Th1-polarized cells were injected. Systolic blood pressure (SBP) was measured throughout pregnancy. Mice were sacrificed at day 15 of pregnancy. Following transfer of Th1-polarized cells, SBP of pregnant WT mice increased (118 ± 3 mmHg to 142 ± 5 mmHg). Although ultrastructural changes were evident in the kidney this was not accompanied by significant proteinuria. SBP remained unchanged (115 ± 2 mmHg to 114 ± 3 mmHg) in pregnant CD39TG mice without evidence of renal lesions. We conclude that gestational hypertension can be induced in mice following transfer of maternally derived Th1-polarized cells and that overexpression of CD39 is protective in this model.

The role of Cancer-Testis antigens as predictive and prognostic markers in non-small cell lung cancer

Background

Cancer-Testis Antigens (CTAs) are immunogenic proteins that are poor prognostic markers in non-small cell lung cancer (NSCLC). We investigated expression of CTAs in NSCLC and their association with response to chemotherapy, genetic mutations and survival.

Methods

We studied 199 patients with pathological N2 NSCLC treated with neoadjuvant chemotherapy (NAC; n = 94), post-operative observation (n = 49), adjuvant chemotherapy (n = 47) or unknown (n = 9). Immunohistochemistry for NY-ESO-1, MAGE-A and MAGE-C1 was performed. Clinicopathological features, response to neoadjuvant treatment and overall survival were correlated. DNA mutations were characterized using the Sequenom Oncocarta panel v1.0. Affymetrix data from the JBR.10 adjuvant chemotherapy study were obtained from a public repository, normalised and mapped for CTAs.

Results

NY-ESO-1 was expressed in 50/199 (25%) samples. Expression of NY-ESO-1 in the NAC cohort was associated with significantly increased response rates (P = 0.03), but not overall survival. In the post-operative cohort, multivariate analyses identified NY-ESO-1 as an independent poor prognostic marker for those not treated with chemotherapy (HR 2.61, 95% CI 1.28–5.33; P = 0.008), whereas treatment with chemotherapy and expression of NY-ESO-1 was an independent predictor of improved survival (HR 0.267, 95% CI 0.07–0.980; P = 0.046). Similar findings for MAGE-A were seen, but did not meet statistical significance. Independent gene expression data from the JBR.10 dataset support these findings but were underpowered to demonstrate significant differences. There was no association between oncogenic mutations and CTA expression.

Conclusions

NY-ESO-1 was predictive of increased response to neoadjuvant chemotherapy and benefit from adjuvant chemotherapy. Further studies investigating the relationship between these findings and immune mechanisms are warranted.

The prognostic significance of aldehyde dehydrogenase 1A1 (ALDH1A1) and CD133 expression in early stage non-small cell lung cancer

BACKGROUND

Expression of aldehyde dehydrogenase 1A1 (ALDH1A1) and CD133 has been functionally associated with a stem cell phenotype in normal and malignant cells. The prevalence of such cells in solid tumours should therefore correlate with recurrence and/or metastasis following definitive surgical resection. The aim of this study was to evaluate the prognostic significance of ALDH1A1 and CD133 in surgically resected, early stage non-small cell lung cancer (NSCLC).

METHODS

A retrospective analysis of ALDH1A1 and CD133 expression in 205 patients with pathologic stage I NSCLC was performed using immunohistochemistry. The association between the expression of both markers and survival was determined.

RESULTS

We identified 62 relapses and 58 cancer-related deaths in 144 stage 1A and 61 stage 1B patients, analysed at a median of 5-years follow-up. Overexpression of ALDH1A1 and CD133, detected in 68.7% and 50.7% of primary tumours, respectively, was an independent prognostic indicator for overall survival by multivariable Cox proportional hazard model (p=0.017 and 0.039, respectively). Overexpression of ALDH1A1, but not of CD133, predicted poor recurrence-free survival (p=0.025). When categorised into three groups according to expression of ALDH1A1/CD133, patients with overexpression of both ALDH1A1 and CD133 belonged to the group with the shortest recurrence-free and overall survival (p=0.015 and 0.017, respectively).

CONCLUSIONS

Expression of ALDH1A1 and CD133, and coexpression of ALDH1A1 and CD133, is strongly associated with poor survival in early-stage NSCLC following surgical resection. These data are consistent with the hypothesis that expression of stem cell markers correlates with recurrence as an indirect measure of self-renewal capacity.

Intravenous leiomyomatosis with intracardiac extension - a review of diagnosis and management with an illustrative case

Intravenous leiomyomatosis with intracardiac extension is an uncommon pathologic progression of uterine leiomyomata. It is a histologically benign condition, however due to interfence with right sided cardiac function patients may present with marked cardiovascular compromise and present a diagnostic dilemma to clinicians who are unfamiliar with this condition. Given the rarity of this condition, experience in individual institutions is usually limited to a few cases. We present an illustrative case and provide a review of the clinical presentation, preoperative assessment, operative approach, pathology and postoperative issues. The importance of a multidisciplinary approach to diagnosis and management is highlighted. Operative management aims to completely resect all tumour in the safest manner for the patient, most commonly via single or two stage operation. Where complete resection is achieved, recurrence appears to be a rare event.

Recurrent myocarditis--an important mimic of ischaemic myocardial infarction

Patients presenting with a syndrome of chest pain, elevated cardiac enzyme levels with or without electrocardiogram changes are a common diagnostic and management problem in cardiology. Most commonly, this is due to ischaemic myocardial infarction secondary to coronary artery disease. However, when coronary angiography does not demonstrate any obstructive coronary artery lesion, the diagnosis of myocarditis should be considered. Cardiac magnetic resonance imaging is helpful towards making this diagnosis. Here, we describe the first reported Australian cases of recurrent myocarditis presenting with ischaemic chest pain and elevated cardiac enzyme levels. These cases serve as an important reminder to clinicians that myocarditis is an important mimic of ischaemic myocardial infarction.

Sex and SUVmax: sex-dependent prognostication in early non-small cell lung cancer

The identification of robust prognostic factors for patients with early-stage non-small cell lung cancer (NSCLC) is clinically important. The International Association for the Study of Lung Cancer has identified both sex and the maximum standardized uptake value (SUVmax) of (18)F-FDG in the primary tumor as measured by PET as potential prognostic variables. We examined the prognostic value of SUVmax in a surgical cohort of patients with NSCLC and disaggregated the findings by sex.

METHODS

Patients who had undergone a preoperative PET/CT scan and surgical resection with curative intent from 2001 to 2009 were identified from a prospective database. An SUVmax cutoff was calculated using receiver-operating-characteristic curves. Overall survival was correlated with SUVmax for the whole cohort and disaggregated by sex.

RESULTS

Inclusion criteria were met by 189 patients: 127 (67%) men and 62 (33%) women. Five-year survival was 54.6% for the whole cohort, 47.7% for men, and 68.2% for women. SUVmax correlated negatively with survival in a univariate analysis for the whole cohort (hazard ratio [HR], 2.51; 95% confidence interval [CI], 1.54-4.09; P < 0.001) and men (HR, 3.42; 95% CI, 1.94-6.05; P < 0.001) but not for women (HR, 1.61; 95% CI, 0.43-3.12; P = 0.77), using 8 as a cutoff. In multivariate analysis, SUVmax correlated with overall survival for the whole cohort (HR, 1.70; 95% CI, 1.05-2.99; P = 0.05) and men (HR, 2.40; 95% CI, 1.32-4.37; P = 0.004) but not for women (HR, 0.80; 95% CI, 0.15-4.47; P = 0.80).

CONCLUSION

SUVmax independently predicted overall survival for men but not for women in this surgical cohort. Our results suggest that SUVmax is an independent prognostic variable in men with surgically treated early NSCLC.