Won-Suk Lee

Clinical Outcomes of Hepatic Resection and Radiofrequency Ablation in Patients With Solitary Colorectal Liver Metastasis

Background The role of the radiofrequency ablation (RFA) in treatment of solitary liver metastasis has not been established yet. Both hepatic resection (HR) and RFA have been used increasingly in the treatment of colorectal liver metastases. Study A systemic review was performed to determine the impact of treatment modality of solitary liver metastasis on recurrence patterns, disease-free survival, and overall survival (OS) rates. Results Solitary liver metastases were treated by HR in 116 patients (75.8%) and 37 patients (24.2%) were treated with RFA. Prognostic factors, recurrence rate, recurrence patterns, and survival rates were analyzed. The cumulative 3-year and 5-year local recurrence free survival rates were markedly higher in the HR group (88.0% and 84.6%) as compared with those in the RFA group [53.3% and 42.6%, respectively (P≤0.001)]. The 5-year OS rate was lower in the RFA group as compared with the HR group without statistical significance (5-year OS, 65.7% in the HR, 48.5% in the RFA group, P=0.227). Conclusions Despite of higher local recurrence rate, RFA may be considered as a therapeutic option for patients who are considered unsuitable for conventional surgical treatment. Randomized prospective controlled trials comparing the therapeutic outcome of RFA and HR are definitely warranted.

Tumor localization for laparoscopic colorectal surgery

BackgroundBecause palpating colonic tumors during laparoscopy is impossible, the precise location of a tumor must be identified before operation. The aim of this study was to evaluate the accuracy of various diagnostic methods that are used to localize colorectal tumors and to propose an adequate localization protocol for laparoscopic colorectal surgery.MethodsA total of 310 patients underwent laparoscopy-assisted colectomy between April 2000 and March 2006. We investigated if the locations of the tumors that were estimated preoperatively were consistent with the actual locations according to the operation.ResultsAll the tumors were correctly localized and resected. Altogether, 203 patients had complete endoscopic reports available. Colonoscopy was inaccurate for tumor localization in 23 cases (11.3%). In total, 104 patients (33.5%) underwent barium enema; five tumors (4.8%) were not visualized, and three tumors were incorrectly localized. Another group of 94 patients (30.3%) underwent computed tomography (CT) colonography, which identified 91 of 94 lesions (96.8%). Finally, 96 patients (31.0%) underwent endoscopic tattooing; 2 patients (2.1%) did not have tattoos visualized laparoscopically and required intraoperative colonoscopy to localize their lesions during resection. Dye spillage was found in six patients intraoperatively, but only one patient experienced clinical symptoms. Intraoperative colonoscopy was performed in four patients; two of the four were followed by endoscopic tattooing, and the other two underwent intraoperative colonoscopy for localization. All lesions were correctly localized by intraoperative colonoscopy. The accuracy of tumor localization was as follows: colonoscopy (180/203, 88.7%), barium enema (97/104, 93.3%), CT colonography (89/94, 94.7%), endoscopic tattooing (94/96, 97.9%), and intraoperative colonoscopy (4/4, 100%).ConclusionsWith a combination of methods, localization of tumors for laparoscopic surgery did not seem very different from that during open surgery. Preoperative endoscopic tattooing is a safe, highly effective method for localization. In the case of tattoo failure, intraoperative colonoscopy can be used for accurate localization.

Comparison of combined hepatocellular and cholangiocarcinoma with hepatocellular carcinoma and intrahepatic cholangiocarcinoma.

PurposeCombined hepatocellular and cholangiocarcinoma (HCC-CC) is a rare primary hepatic neoplasm (PHN) with features of both hepatocellular and biliary differentiation. We compared the outcome of hepatic resection in patients with HCC-CC, those with hepatocelluar carcinoma (HCC), and those with cholangiocarcinoma (ICC).MethodsBetween November 1994 and December 2003, 952 patients underwent hepatic resection for a PHN.ResultsThe incidence of HCC-CC was 3.5%. Hepatitis B surface antigen was positive in 51.2% of these patients and the HCV antibody was positive in 12.2%. Positive hepatitis serology was more common in the HCC group (66.7%). The prevalence of underlying liver cirrhosis was significantly lower in the ICC group (7.8%) than in the HCC (49%) and HCC-CC (41.5%) groups (P < 0.0001). The median overall survival periods after hepatic resection of HCC-CC, HCC, and ICC were 47.3, 71.7, and 21.5 months, respectively (P < 0.0001). The median disease-free survival (DFS) periods after hepatic resection for HCC-CC, HCC, and ICC were 23.4, 68.2, and 15.5 months, respectively (P < 0.0001).ConclusionPatients with transitional type HCC-CC had significantly poorer survival rates than those with HCC, after hepatic resection. Therefore, a more aggressive treatment modality should be explored to improve the survival rate of these patients.

Prospective blinded study of somatic mutation detection in cell-free DNA utilizing a targeted 54-gene next generation sequencing panel in metastatic solid tumor patients

Sequencing of the mutant allele fraction of circulating cell-free DNA (cfDNA) derived from tumors is increasingly utilized to detect actionable genomic alterations in cancer. We conducted a prospective blinded study of a comprehensive cfDNA sequencing panel with 54 cancer genes. To evaluate the concordance between cfDNA and tumor DNA (tDNA), sequencing results were compared between cfDNA from plasma and genomic tumor DNA (tDNA). Utilizing next generation digital sequencing technology (DST), we profiled approximately 78,000 bases encoding 512 complete exons in the targeted genes in cfDNA from plasma. Seventy-five patients were prospectively enrolled between February 2013 and March 2014, including 61 metastatic cancer patients and 14 clinical stage II CRC patients with matched plasma and tissue samples. Using the 54-gene panel, we detected at least one somatic mutation in 44 of 61 tDNA (72.1%) and 29 of 44 (65.9%) cfDNA. The overall concordance rate of cfDNA to tDNA was 85.9%, when all detected mutations were considered. We collected serial cfDNAs during cetuximab-based treatment in 2 metastatic KRAS wild-type CRC patients, one with acquired resistance and one with primary resistance. We demonstrate newly emerged KRAS mutation in cfDNA 1.5 months before radiologic progression. Another patient had a newly emerged PIK3CA H1047R mutation on cfDNA analysis at progression during cetuximab/irinotecan chemotherapy with gradual increase in allele frequency from 0.8 to 2.1%. This blinded, prospective study of a cfDNA sequencing showed high concordance to tDNA suggesting that the DST approach may be used as a non-invasive biopsy-free alternative to conventional sequencing using tumor biopsy.

Treatment outcomes of hepatic and pulmonary metastases from colorectal carcinoma

Background and Aim:  The resection of synchronous or metachronous pulmonary and liver metastasis is an aggressive treatment option for patients with stage IV colorectal cancer and has been shown to yield acceptable long‐term survival. We reviewed our experience with colorectal cancer patients with both liver and lung resections to determine the efficacy of surgical resections.

Intra-operative Measurement of Surgical Lengths of the Rectum and the Peritoneal Reflection in Korean

The lengths of the surgical rectum and peritoneal reflection were important factors in treatment modality of rectal tumor. To evaluate the surgical length of rectum, we measured the length of the peritoneal reflections, sacral promontory and termination of the taenia coli from the anal verge by rigid sigmoidoscope in 23 male and 23 females during operation. The mean lengths of the sacral promontory were 16.5± 2.2 cm and 16.1±2.2 cm in the males and females, respectively. As for the peritoneal reflection, the results were anterior (8.8±2.2 cm, 8.1±1.7 cm), lateral (10.8±2.7 cm, 11.4±1.9 cm) and posterior (13.8±2.5 cm, 14.0±1.9 cm), respectively. There were no statistically significant differences between male and female. And only height had a correlation with the length of sacral promontory both in male and female (p=0.015 and p=0.018, respectively). For all the estimated lengths, the length of the sacral promontory had a correlation with the lengths of the anterior (p<0.001 and p=0.001) and posterior (p<0.001 and p<0.001) peritoneal reflections in males and females, respectively. We suggest that the intra-operative lengths of the rectum and peritoneal reflection will be useful information for treatment modality of rectal tumor clinically in Korean.

Clinical usefulness of chest radiography in detection of pulmonary metastases after curative resection for colorectal cancer.

PurposeThe purpose of this study was to evaluate the effectiveness of chest radiography (CXR) and abdominal computed tomography (CT) for detecting pulmonary metastases after curative surgery for colorectal cancer.MethodsWe performed a retrospective analysis of the records of all patients with pulmonary metastasis from colorectal cancer who underwent curative resection between 1994 and 2004 at our institution. ResultsPulmonary metastases were detected in 193 patients by either CXR or abdominal CT. They were initially detected by CXR in 87 patients (45.1%) and by abdominal CT in 106 patients (54.9%). In the CXR group, the patterns of pulmonary recurrence were as follows: solitary (n = 38, 43.7%), multiple unilateral (n = 11, 12.6%), and multiple bilateral (n = 38, 43.7%). In the CT group, there were 22 patients (20.8%) with a solitary nodule, 17 patients (16.0%) with multiple unilateral nodules, and 67 (63.2%) with multiple bilateral nodules. The overall survivals of the CXR group and abdominal CT group were 34.6% and 31.7%, respectively (p = 0.312). There was no difference in the median disease-free interval between the CXR group and the abdominal CT group (23.8 vs. 23.2 months, p = 0.428).ConclusionsAlthough this study is limited by its small sample size, it can be speculated that abdominal CT with lower thorax images may replace CXR in surveillance programs.

Anal canal carcinoma: experience from a single Korean institution.

Purpose The clinical features, treatment modality approaches in clinical practice, and prognostic factors for anal canal carcinoma patients were retrospectively analyzed. Materials and Methods Between October 1994 and December 2005, 50 patients with anal canal cancer were treated at Samsung Medical Center, Seoul, Korea. Results After a median follow up of 37.8 months (range, 6.6 - 136.1 months), the 5-year and 10-year survival rates for the 38 patients with early and locally advanced squamous and cloacogenic carcinoma (squamous cell carcinoma and cloacogenic carcinoma) were 74.8% and 66.5%, respectively. The 5-year survival and disease-free survival rates (DFS) of the 31 patients who received chemoradiation therapy (CRT) were 83.6% and 74.3%, respectively. The overall and DFS could not be determined for the adenocarcinoma group due to the small number of cases (n = 8). Univariate analysis showed that tumor size (p = 0.04) and inguinal node status (p = 0.04) significantly influenced patient survival in patients with squamous cell and cloacogenic carcinomas. Furthermore, univariate analysis also showed that, inguinal node status influenced patient survival in the adenocarcinoma group. Multivariate analysis showed that inguinal node metastasis is a single independent prognostic variable for survival (p = 0.04) in patients with squamous cell and cloacogenic carcinomas. Conclusion Combined CRT has been adopted as standard treatment with outcomes that are comparable to those reported in randomized clinical trials. Due to the rarity and complexity of anal canal carcinoma, interdepartmental cooperation is required for disease treatment. Thus, proper treatment of patients should incorporate a team-approach and should be available to as many patients as possible.

Colonic perforation caused by anorectal manometry

Dear Editor: A 63-year-old male visited our hospital with a chief complaint of an anal protruding mass. On rectal examination, there were grade III hemorrhoids with partial mucosal prolapse. Anorectal manometry (ARM) was performed in order to inspect the anorectal function. ARM was done with using an eight-channel water-perfused system (TA 6000 Micropulsing®, Gould, Valley View, OH, USA) and a balloon-attached catheter (Zinetics Manometric Catheter®, Medtronic, Copenhagen, Denmark). The manometry results showed paradoxical contraction of the anal sphincter when straining but no other unusual features. During the examination, the patient only expressed a slight discomfort in the lower abdomen. When he arrived at home, he felt lower abdominal pain and had a large amount of hematochezia. The frequency and amount of hematochezia decreased, and at first, he observed this symptom without informing the clinician of it. He visited hospital after 2 days and complained of abdominal distension and nausea. His vital signs were as follows: a blood pressure of 129/ 108, a heart rate of 127 beats per minute, a respiratory rate of 22 breaths per minute, and a temperature of 36.5°C. The abdominal examination was notable for diffuse abdominal tenderness with guarding. The laboratory studies showed a white blood cell count of 13,580/mm, a hemoglobin level of 16.6 g/dl, and a platelet count of 188,000/mm. The plain abdominal films showed distended small bowel loops with air-fluid levels. A computed tomography showed a short segment of wall disruption on the sigmoid colon and a collection of fluid and extraluminal air surrounding the sigmoid colon. He was taken to the operation room for exploration. Exploratory laparotomy through a lower midline incision showed a severely distended small bowel. However, there was no fecal or purulent material throughout the peritoneal cavity. Examination of the sigmoid colon and rectum showed a full-thickness perforation at the level of the rectosigmoid junction. We performed a Hartmann’s procedure, with resection of the sigmoid colon and upper rectum, closure of the rectum beneath the site of perforation, and sigmoid end colostomy. A perforation of about 8 cm in length was measured in the resected specimen. Gas was passed through the stoma on the fourth postoperative day, and the postoperative course was uneventful. Manometry is an objective method of assessing anal sphincter function and it is an important tool for managing defecatory disorders. Manometry has been widely used for investigating patients with fecal incontinence to identify the presence of sensory or muscular defects, as well as to define functional weakness of the internal and/or external anal sphincter. Manometry is also used before performing procedures to document those sphincter functions that may affect continence or require optimizing continence. In addition, manometry has been regard as a safe procedure because there have been no reports on complications or problems while performing manometry. Lee et al. reported that they experienced two cases of colorectal rupture during the measuring the maximum tolerable volume [Lee et al. (1998) Colorectal rupture: an unusual complication of anorectal manometry. Korean J Gastrointest Motil 4:118–122]. Both patients were in their Int J Colorectal Dis (2008) 32:219–220 DOI 10.1007/s00384-007-0312-0

The clinical outcome and prognostic factors after multi-visceral resection for advanced colon cancer.

AIM The value of multi-visceral resection (MVR) for treating primary advanced colon cancer infiltrating into the neighboring organs had been debated because of the high mortality. METHODS We reviewed 1288 patients who underwent curative resection for pT3-4 colon cancer without distant metastasis from 1994 to 2004. RESULTS Eighty four patients (6.5%) with colon cancer infiltrating into the neighboring organs (cT4) underwent MVR. The accuracy of the intra-operative decision for true invasion (pT4) was 35.7%. Major surgical morbidity occurred in 11 patients of the standard resection group (0.9%) and in 2 patients of the MVR group (2.3%) (p = 0.206). Most of the recurrence was distant metastasis (20 patients, 23.8%). Local recurrence was occurred in five patients (6.0%). The prognostic factors for recurrence and survival were pathologic tumor invasion (p = 0.033 and p = 0.016, respectively) and lymph node metastasis (p = 0.010 and p < 0.001, respectively). CONCLUSION Multi-visceral resection was a safe and curative procedure as compared with standard resection for patients with advanced colon cancer. The cause of a poor prognosis in MVR was not local recurrence but distant metastasis. Pathologic tumor invasion and lymph node metastasis were the potential prognostic factors.