Molecular staging of lung and esophageal cancer

Prognostic significance of global histone modifications in resected squamous cell carcinoma of the esophagus

Patterns of global histone modifications have been recently suggested as outcome predictors in cancer patients. To date, there has been no report on the prognostic significance of global histone modifications in esophageal squamous cell carcinoma. We investigated the role of global histone modification as outcome predictor in patients undergoing esophagectomy for esophageal squamous cell carcinoma. A retrospective clinicopathologic analysis was undertaken of 97 patients with esophageal squamous cell carcinoma who recovered from esophagectomy. Immunohistochemical expression of five histone modification markers, acetylated histone 3 lysine 18 (H3K18Ac), acetylated histone 4 lysine 12 (H4K12Ac), dimethylated histone 4 arginine 3 (H4R3diMe), dimethylated histone 3 lysine 4 (H3 K4diMe), and trimethylated histone 3 lysine 27 (H3K27triMe) was assessed in paraffin-embedded tumor samples. Results were analyzed in relation to patients' clinicopathologic parameters. There was a positive relationship between tumor differentiation and H3K18Ac (P<0.001), H4R3diMe (P=0.003), and H3K27triMe (P<0.001). Expression of H3K27triMe correlated positively with nodal (N) status (P=0.012) and stage (P=0.025). Univariate analysis showed that better survival in patients with low expression of H3K18Ac (P=0.038) and H3K27triMe (P=0.003). Multivariate analysis showed that nodal status, metastasis status (M), and expression of H3K27triMe predicted survival independently (P<0.001, P=0.016, and 0.048, respectively). Low expression of H3K18Ac and H3K27triMe correlated with better prognosis of patients with esophageal squamous cell carcinoma, especially for those of early stages. We hypothesize that expression of H3K27triMe may be considered as a significant survival predictor for patients with esophageal squamous cell carcinoma.

Quantitative c-erbB-2 but not c-erbB-1 mRNA expression is a promising marker to predict minor histopathologic response to neoadjuvant radiochemotherapy in oesophageal cancer

We examined the potential of quantitative epidermal growth factor receptor (EGFR, synonym: c-erbB-1) and c-erbB-2 (synonym: HER2/neu) mRNA expression to predict minor or major histopathologic response to neoadjuvant radiochemotherapy (cis-platinum, 5-FU, 36 Gy), followed by radical surgical resection, in patients with oesophageal cancer. Tissue samples were collected by endoscopic biopsy prior to treatment. RNA was isolated from biopsies and quantitative real-time reverse transcriptase–polymerase chain reaction assays were performed to determine c-erbB-1 and c-erbB-2 mRNA expression. Relative expression (tumour/paired normal tissue ratio standardised for β-actin) was calculated for EGFR and c-erbB-2 mRNA. Expression levels were correlated with the objective histopathologic response in resected specimens. Histomorphologic regression was defined as major response when resected specimens contained less than 10% of residual vital tumour cells, or in case a pathologically complete response was achieved. Expression of c-erbB-1 mRNA was not associated with the degree of histomorphological response. In contrast, the relative expression levels of c-erbB-2 mRNA >1 were not associated with major histopathologic responses (sensitivity 41.6%, specificity 100%), and 10 out of 36 (28%) patients could be unequivocally identified, whose tumours did not respond well to the delivered neoadjuvant radiochemotherapy (P<0.01). Quantitative expression levels of c-erbB-2, but not c-erbB-1 mRNA, in pretreatment biopsies appear to predict minor histopathologic response to our neoadjuvant radiochemotherapy protocol. This test could be used to prevent expensive, noneffective and potentially harmful therapies in approximately one-fourth of our patients, and leads to a more individualised type of combined modality treatment.

Significance of post-chemoradiation biopsy in predicting residual esophageal carcinoma in the surgical specimen

Pathologic complete response in the resected esophagus can be achieved in approximately 30% of patients with locally advanced esophageal or gastroesophageal junction carcinoma after preoperative chemoradiation therapy. These patients tend to have a longer survival than those who have less than pathologic complete response. Post-chemoradiation esophageal biopsy (PCEB) is used to check for the presence of residual tumor before a definitive resection is performed, but the clinical significance of PCEB findings is not clear due to the possibility of sampling bias and the superficial nature of the specimen obtained. We evaluated the use of PCEB (defined as biopsy taken within 30 days before esophagectomy) in predicting residual cancer in post-treatment esophagectomy specimens. PCEB was performed in 65 of 183 (36%) patients with locally advanced esophageal or gastroesophageal junction carcinoma, who received preoperative chemoradiation therapy. The cancer status in PCEB was correlated with the residual cancer in the esophagectomy specimens. PCEB had no cancer in 80% (52 of 65) of patients (Bx-negative) and cancer in 20% (13 of 65) of patients (Bx-positive). There was no difference in the presence of residual cancer (either in esophagus or lymph node) in esophagectomy specimens between Bx-negative patients (77%, 40 of 52) or Bx-positive patients (92%, 12 of 13), P = 0.44. The positive predictive value of biopsy was 92% (12 of 13), negative predictive value 23% (12 of 52), sensitivity 23% (12 of 52) and specificity 92% (12 of 13). There was no difference in the residual cancer staging in the esophagectomy specimen between Bx-positive and Bx-negative patients. In contrast, residual metastatic carcinoma in lymph nodes was more frequent in Bx-positive patients (69.2%, 9 of 13) than in Bx-negative patients (28.8%, 15 of 52), P = 0.01. Our data suggest that PCEB is a specific but not a sensitive predictor of residual cancer following esophagectomy. Bx-positive patients tend to have more frequent residual tumor in lymph nodes. The utility of PCEB in predicting residual cancer in the lymph nodes needs to be explored further along with molecular predictors of response to preoperative therapy.

p27 and Barrett's esophagus: a review*

The rising prevalence of Barrett's esophagus and Barrett's associated adenocarcinoma in the Western world has stimulated increasing interest in this disease. This has resulted in a plethora of articles concerning its molecular biology, but the tumor suppressor gene, p27, has received little attention. In this article, we review the literature concerning the role of p27 in Barrett's esophagus and its malignant transformation, and we evaluate its possible role as an important clinical biomarker, as well as potential chemopreventive clinical agents aimed at substituting its antitumoral activity.

Lung cancer staging

The staging of lung cancer is a continuously progressing field, with advances in technology not only improving prognostic accuracy, but fundamentally changing pre-operative investigation algorithms. Noninvasive staging is currently undergoing revolutionary developments with the advent of Positron Emission Tomography, whereas Video-Assisted Thoracic Surgery has already been established as an essential, minimally invasive diagnostic tool for invasive histological staging. Molecular staging may transform future lung cancer staging, promising extremely accurate substaging, and potentially prompting a revision of our anatomically based conceptualization of lung cancer spread. This review presents an appraisal of current lung cancer staging modalities, and presents an overview of recent developments in molecular staging.