Impact of Procedure Volumes and Focused Practice on Short-Term Outcomes of Elective and Urgent Colon Cancer Resection in Italy

<div><p>Background</p><p>The relationship between hospital volumes and short-term patients’ outcomes of colon cancer (CC) surgery is not well established in the literature. Moreover, evidence about short-term outcomes of urgent compared with elective CC procedures is scanty. The aims of this study are 1) to determine whether caseloads and other hospital characteristics are associated with short-term outcomes of CC surgery; 2) to compare the outcomes of urgent and elective CC surgery.</p><p>Methods</p><p>A total of 14,200 patients undergoing CC surgery between 2005 and 2010 in the General Surgery Units (GSUs) of the hospitals of Emilia-Romagna region, Northern Italy, were identified from the hospital discharge records database. The outcomes of interest were 30-day in-hospital mortality, re-intervention and 30-day re-admission. Using multilevel analysis, we analyzed the relationship of GSU volumes and focused practice, defined as the percentage of CC operations over total operations, with the three outcomes.</p><p>Results</p><p>High procedure volumes were associated with a lower risk of 30-day in-hospital mortality, after adjusting for patients’ characteristics [aOR (95% CI) = 0.51 (0.33–0.81)]. Stratified analyses for elective and urgent surgery showed that high volumes were associated with a lower 30-day mortality for elective patients [aOR (95% CI) = 0.35 (0.17–0.71)], but not for urgent patients [aOR (95% CI) = 0.72 (0.42–1.24)]. Focused practice was an independent predictor of re-intervention [aOR (95% CI) = 0.67 (0.47–0.97)] and re-admission [aRR (95% CI) = 0.88 (0.78–0.98)].</p><p>Conclusions</p><p>The present study adds evidence in support of the notion that patients with CC undergoing surgery at high-volume and focused surgical units experience better short-term outcomes.</p></div

Proposed algorithm for the detection of <i>KRAS</i> mutations in EUS-FNA material from pancreatic lesions.

<p>Ex, Exon; WT, Wild-Type.</p

Example of molecular results in a <i>KRAS</i> exon 2 mutated sample (case #57, Table 4) with discordant results between the three techniques.

<p>A) Electropherogram obtained using Sanger sequencing. The mutation is not identified. B) Using ASLNAqPCR the <i>KRAS</i> G12D mutation is identified by the right curve (G12D). The left curve indicates the wild-type allele (WT). The ratio between the two curves corresponds to ∼6% of mutated alleles. C) Profile obtained using 454-NGS, the <i>KRAS</i> G12D mutation is identified by the vertical green bar. The percentage of mutated alleles is indicated on the left y axis while the total number of reads on the right one.</p

Multiple <i>KRAS</i> mutations according to different techniques.

<p>PDAC, Pancreatic Ductal AdenoCarcinoma; IPMN, Intraducatal Pancreatc Mucinous Neoplasia; NA, end-point not available.</p

Percentage of mutated <i>KRAS</i> samples according to preoperative cytology evaluation.

<p>ASLNAqPCR, Allele Specific Locked Nucleic Acid qPCR; NGS, Next Generation Sequencing; PDAC, Pancreatic Ductal AdenoCarcinoma; Not PDAC, malignant neoplasia but not Pancreatic Ductal Adenocarcinoma; NA, cytology not available.</p

Example of molecular results in a <i>KRAS</i> exon 3 mutated sample (case #37, Table 4).

<p>A) Electropherogram obtained using Sanger sequencing. The <i>KRAS</i> Q61H mutation is identified by the smaller pick pointed by the arrow. B) No <i>KRAS</i> mutation was detected using ASLNAqPCR results: only the curve corresponding to the wild-type allele is visible (WT). C) Profile obtained using 454-NGS, the <i>KRAS</i> Q61H mutation is identified by the vertical blue bar. The percentage of mutated alleles is indicated on the left y axis while the total number of reads on the right one.</p

Statistical performance of <i>KRAS</i> molecular analysis using 454-NGS starting only from FNA material or adding the results obtained in DNA extracted from cytologic smears (in bold).

<p>SPEC, Specificity; SENS, Clinical Sensitivity; PPV, Positive Predictive Value; NPV; Negative Predictive Value; ACC; Accuracy; FDR, False Discovery Rate.</p

Example of molecular results in a <i>KRAS</i> exon 2 mutated sample.

<p>A) Electropherogram obtained using Sanger sequencing. The <i>KRAS</i> G12D mutation is identified by the smaller peak pointed by the arrow. B) Using ASLNAqPCR results the <i>KRAS</i> G12D mutation is identified by the right curve (G12D). The left curve indicates the wild-type allele (WT). C) Profile obtained using 454-NGS, the <i>KRAS</i> G12D mutation is identified by the vertical green bar. The percentage of mutated alleles is indicated on the left y axis while the total number of reads on the right one.</p