RESUMO
Introduction: There is considerable variation in selection of patients for and type of neoadjuvant radiotherapy administered in the treatment of resectable rectal cancer. The aim of this study was to report outcomes for patients with resected rectal cancer from a unit with step-wise selection for surgery alone, short course radiotherapy (SCRT) or downstaging long course chemoradiotherapy (LCCRT). Material and methods: Cohort analysis of patients with rectal adenocarcinoma resected with curative intent between 2008 and 2012 at a specialist regional colorectal surgery center. The primary endpoints were local recurrence, metastatic recurrence, disease-free survival and overall survival. Exploratory uni- and multi-variable regression analyses were performed to identify predictive factors. Results: About 240 patients were treated by surgery alone, 90 patients received SCRT and 91 patients received LCCRT. Five-year local recurrence was 10.8% in the surgery alone group, 3.3% with SCRT and 18.7% with LCCRT. Metachronous distant metastasis was highest in the SCRT group (13.8% surgery alone, 25.6% SCRT, 15.4% LCCRT). Uni- and multi-variable regression analysis found that local and distant recurrence was attributable predominantly to adverse tumor biology. Conclusions: Patients selected for SCRT had a lower rate of local recurrence than patients selected for surgery alone, but were more likely to develop distant metastasis. There was no difference in overall survival. With low local recurrence rates, distant metastasis is the predominant risk for patients with resectable rectal cancer.
Assuntos
Adenocarcinoma/terapia , Terapia Neoadjuvante , Recidiva Local de Neoplasia , Neoplasias Retais/terapia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia/métodos , Quimiorradioterapia/estatística & dados numéricos , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/estatística & dados numéricos , Seleção de Pacientes , Radioterapia Adjuvante/métodos , Radioterapia Adjuvante/estatística & dados numéricos , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Análise de Regressão , Fatores de Tempo , Adulto JovemRESUMO
Human basal cell carcinoma (BCC) offers a unique opportunity to assess directly the microvascular abnormalities in a human cancer in vivo. Our objectives were to assess angiogenesis, perfusion, and changes in small solute exchange kinetics. The microcirculation of BCC and a normal (control) skin site was studied in 15 patients by laser Doppler fluximetry and videoangiography after rapid i.v. fluorescein injection. Microvascular morphometry was analyzed off line. Sodium fluorescein accumulation/clearance was recorded for 30 min, and fluorescence intensity (FI) was quantified by computer analysis of videotape image gray levels. In BCCs, the microvascular area fraction was 2.6-fold greater, microvessel length density 2.0-fold greater, average vessel image width 2.1-fold greater, and red cell flux 3.9-fold greater than in control sites (P < 0.01, paired t tests). The initial rate of rise of FI over 10 s was approximately 3-fold greater in BCC than control and correlated with vascular area fraction and red cell flux. Tissue then equilibrated faster in BCC, rate constant -(13.0 +/- 5.6) x 10(-3) s(-1) (mean +/- SD), than controls -(5.3 +/- 1.7) x 10(-3) s(-1), and plasma clearance was 2.6-fold higher in BCC than controls (P < 0.01, paired t test). Similarly, the rate constant of the subsequent clearance phase was approximately 2-fold greater in BCC, -(0.53 +/- 0.19) x 10(-3) s(-1), than controls, -(0.27 +/- 0.22) x 10(-3) s(-1) (P < 0.01). Removal rate constants were an order of magnitude slower than accumulation rate constants. The results demonstrate angiogenesis, increased perfusion, and a more rapid exchange of small solute in human BCC. FI itself is rejected as an index of permeability to small solutes (cf. 29) because it depends also on blood flow, endothelial area, microvascular volume, and interstitial fluid volume.