Gene Expression Classification of Colon Cancer into Molecular Subtypes: Characterization, Validation, and Prognostic ValueBACKGROUND: Colon cancer (CC) pathological staging fails to accurately predict recurrence, and to date, no gene expression signature has proven reliable for prognosis stratification in clinical practice, perhaps because CC is a heterogeneous disease. The aim of this study was to establish a comprehensive molecular classification of CC based on mRNA expression profile analyses. METHODS AND FINDINGS: Fresh-frozen primary tumor samples from a large multicenter cohort of 750 patients with stage I to IV CC who underwent surgery between 1987 and 2007 in seven centers were characterized for common DNA alterations, including BRAF, KRAS, and TP53 mutations, CpG island methylator phenotype, mismatch repair status, and chromosomal instability status, and were screened with whole genome and transcriptome arrays. 566 samples fulfilled RNA quality requirements. Unsupervised consensus hierarchical clustering applied to gene expression data from a discovery subset of 443 CC samples identified six molecular subtypes. These subtypes were associated with distinct clinicopathological characteristics, molecular alterations, specific enrichments of supervised gene expression signatures (stem cell phenotype-like, normal-like, serrated CC phenotype-like), and deregulated signaling pathways. Based on their main biological characteristics, we distinguished a deficient mismatch repair subtype, a KRAS mutant subtype, a cancer stem cell subtype, and three chromosomal instability subtypes, including one associated with down-regulated immune pathways, one with up-regulation of the Wnt pathway, and one displaying a normal-like gene expression profile. The classification was validated in the remaining 123 samples plus an independent set of 1,058 CC samples, including eight public datasets. Furthermore, prognosis was analyzed in the subset of stage II-III CC samples. The subtypes C4 and C6, but not the subtypes C1, C2, C3, and C5, were independently associated with shorter relapse-free survival, even after adjusting for age, sex, stage, and the emerging prognostic classifier Oncotype DX Colon Cancer Assay recurrence score (hazard ratio 1.5, 95% CI 1.1-2.1, p = 0.0097). However, a limitation of this study is that information on tumor grade and number of nodes examined was not available. CONCLUSIONS: We describe the first, to our knowledge, robust transcriptome-based classification of CC that improves the current disease stratification based on clinicopathological variables and common DNA markers. The biological relevance of these subtypes is illustrated by significant differences in prognosis. This analysis provides possibilities for improving prognostic models and therapeutic strategies. In conclusion, we report a new classification of CC into six molecular subtypes that arise through distinct biological pathways.
Immunogenic death of colon cancer cells treated with oxaliplatinImproved management of invasive pulmonary aspergillosis in neutropenic patients using early thoracic computed tomographic scan and surgery.D. Caillot, Olivier Casasnovas, Alain Bernard et al.|Journal of Clinical Oncology|1997 PURPOSE: The prognosis of invasive pulmonary aspergillosis (IPA) occurring in neutropenic patients remains poor. We studied whether new strategies for early diagnosis could improve outcome in these patients. PATIENTS AND METHODS: Twenty-three histologically proven and 14 highly probable IPAs in 37 hematologic patients (neutropenic in 36) were analyzed retrospectively. RESULTS: The most frequent clinical signs associated with IPA were cough (92%), chest pain (76%), and hemoptysis (54%). Bronchoalveolar lavage (BAL) was positive in 22 of 32 cases. Aspergillus antigen test was positive in 83% of cases when tested on BAL fluid. Since October 1991, early thoracic computed tomographic (CT) scans were systematically performed in febrile neutropenic patients with pulmonary x-ray infiltrates. This approach allowed us to recognize suggestive CT halo signs in 92% of patients, compared with 13% before this date, and the mean time to IPA diagnosis was reduced dramatically from 7 to 1.9 days. Among 36 assessable patients, 10 failed to respond (amphotericin B [AmB] plus fluorocytosyne, n = 2; itraconazole + AmB, n = 8) and died of aspergillosis. Twenty-six patients were cured or improved by antifungal treatment (itraconazole with or without AmB, n = 22; voriconazole, n = 4). In 15 of 16 cases, surgical resection was combined successfully with medical treatment. Achievement of hematologic response, early diagnosis, unilateral pulmonary involvement, and highest level of fibrinogen value < 9 g/L were associated with better outcome. CONCLUSION: In febrile neutropenic patients, systematic CT scan allows earlier diagnosis of IPA. Early antifungal treatment, combined with surgical resection if necessary, improves IPA prognosis dramatically in these patients.
Increasing Volume and Changing Characteristics of Invasive Pulmonary Aspergillosis on Sequential Thoracic Computed Tomography Scans in Patients With NeutropeniaPURPOSE: In patients with neutropenia, thoracic computed tomography (CT) halo and air-crescent signs are recognized as major indicators of invasive pulmonary aspergillosis (IPA). Nevertheless, the exact timing of CT images is not well known. PATIENTS AND METHODS: Seventy-one thoracic CT scans were analyzed in 25 patients with neutropenia with surgically proven IPA. RESULTS: On the first day of IPA diagnosis with early CT scan (d0), a typical CT halo sign was observed in 24 of 25 patients. At that time, the median number of thoracic lesions was two (range, one to six), and pulmonary involvement was bilateral in 12 cases. The halo sign was present in 68%, 22%, and 19% of cases on d3, d7, and d14, respectively. Similarly, the air-crescent sign was seen in 8%, 28%, and 63% of cases on the same days. Otherwise, a nonspecific air-space consolidation aspect was seen in 31%, 50%, and 18% of cases on the same days. The analysis of calculated aspergillary volumes on CT showed that, despite antifungal treatment, the median volume of lesions increased four-fold from d0 to d7, whereas it remained stable from d7 to d14. Overall, 21 patients (84%) were cured by the medical-surgical approach. CONCLUSION: In patients with neutropenia, CT halo sign is a highly effective modality for IPA diagnosis. The duration of the halo sign is short, and it demonstrates the value of early CT. The increase of the aspergillosis size on CT in the first days after IPA diagnosis is not correlated with a pejorative immediate outcome when using a combined medical-surgical approach.
The Lung in Inflammatory Bowel Disease†Respiratory involvement in patients with inflammatory bowel disease (IBD) has been reported mainly since 1976. This form of involvement should clearly be separated from interstitial lung disease due to sulfasalazine or mesalamine, although the distinction may be difficult in some cases. We report the data of an ongoing Registry containing 33 cases (23 cases receiving no drug therapy) with ulcerative colitis or, less often, Crohn's disease, who developed varied bronchopulmonary problems. In several cases, the exact diagnosis and the relation of the bronchopulmonary disease to IBD had not been established for many years, thus delaying effective treatment with steroids. In most cases (28/33), respiratory involvement followed the onset of IBD (8 of these 28 cases were postcolectomy), and in the remainder, respiratory manifestations predated the IBD. Patterns of involvement included: 1) Airway inflammation, in the form of subglottic stenosis, chronic bronchitis, severe chronic bronchial suppuration, bronchiectasis, and chronic bronchiolitis. In cases with large airway involvement, endoscopy showed exuberant inflammatory tissue in the airways and narrowing of tracheal and/or bronchial lumen. Histologically, airways were heavily infiltrated by a dense aggregate of inflammatory cells, and there were mucosal ulcerations. 2) Varied patterns of interstitial lung disease, mainly bronchiolitis obliterans with organizing pneumonia, and pulmonary infiltrates and eosinophilia. (3) Miscellaneous other forms of involvement including striking neutrophilic necrotic parenchymal nodules (corresponding histologically to sterile aggregates of neutrophils), and serositis. Steroids were very effective in the majority of cases. Inhaled steroids were of durable benefit in patients with chronic bronchitis, but less often so in those with chronic bronchial suppuration, bronchiectasis, or chronic bronchiolitis. Steroids administered orally led to marked improvement in patients with interstitial lung disease and necrotic nodules, but lacked effectiveness in several patients with severe airway inflammation or chronic bronchiolitis. Intravenous steroids were required in the initial management of life-threatening complications such as asphyxiating subglottic stenosis or extensive interstitial lung disease. Bronchial lavages with methylprednisolone were effective in some patients with severe airway inflammation. Patients with IBD can develop varied inflammatory complications in the lung, and a sizable fraction of these complications is steroid-sensitive.