Won Choi

Advanced Gastric Carcinoma with Signet Ring Cell Histology

Background: Gastric signet ring cell carcinoma (SRC) is a histological type based on microscopic characteristics and not on biological behavior. This study compared the clinicopathological features and prognosis of advanced SRC with non-signet ring cell adenocarcinoma (NSRC) of the stomach. Methods: We reviewed the records of 4,759 consecutive patients diagnosed with advanced gastric adenocarcinoma who were resected surgically from 1987 to 2003. Of these, 662 patients (13.9%) had SRC and were compared with 4,097 patients with NSRC. Results: Significant differences were noted in tumor size, Borrmann type, depth of invasion, lymph node metastasis, peritoneal dissemination and TNM stage. The cumulative 5-year survival rate for advanced SRC was 42.4%, compared with 50.1% in NSRC (p = 0.009). Multivariate analysis showed that tumor size ≧5 cm, Borrmann III and IV, T3–4 invasion and SRC histology were independent risk factors for lymph node metastasis. Depth of invasion, lymph node metastasis, hepatic and peritoneal metastasis and surgical curability were significant factors affecting survival. SRC histology alone was not an independent prognostic factor. Conclusions: Advanced gastric SRC tends toward deeper tumor invasion and more lymph node and peritoneal metastasis than NSRC. Advanced gastric SRC had a worse prognosis than NSRC. Therefore, curative surgical operation with extended lymph node dissection is recommended.

Changes in Treatment Outcomes of Gastric Cancer Surgery Over 45 Years at A Single Institution

Purpose Although many studies have demonstrated improvements in short-and long-term outcomes of gastric cancer surgery, changes in long-term survival over time are not well-established. This study was conducted to evaluate changes in host, tumor, and treatment factors in patients treated at a single institution over a period of 45-yr. Patients and Methods We retrospectively evaluated 9282 patients with gastric cancer from 1955 to 1999, and divided the 45-yr into 4 time frames based on published articles: 1955 to 1962 (n = 228), 1963 to 1972 (n = 891), 1973 to 1988 (n = 2789), and 1989 to 1999 (n = 5374). Results Remarkable changes were noted in host, tumor, treatment factors, and prognosis. Among host factors, patients of more advanced age were identified in the 4th period and mean age shifted from 49 to 55 yrs. Among tumor factors, early gastric cancers and upper body tumors increased up to 32% and from 7% to 13%, respectively. An increase in the annual number of patients (from 29 to 649), gastrectomies (from 14 to 600), rate of resection (from 50% to 90%), rate of curative resection (up to 92%), and proportion of total gastrectomy (from 8% to 29%) was noted. Operative mortality was reduced from 6.1% to 0.7%. The overall 5-yr survival rate significantly increased from 22% to 65%. Conclusion Treatment results of gastric cancer surgery have improved remarkably over the 45-year period. Increase of early stage gastric cancer with early diagnosis considerably influenced the improved survival of patients with gastric cancer.

The impact of total retrieved lymph nodes on staging and survival of patients with pT3 gastric cancer

The incidence of lymph node metastasis is high in patients who have pT3 gastric cancer. However, the impact of total retrieved lymph nodes (tLNs) on staging and survival of these patients is not clear.

Changing trends in histologic types of lung cancer during the last decade (1981–1990) in Korea: a hospital-based study

A review of the histopathology and past history of 2229 patients with primary lung cancer diagnosed at the Yonsei University Medical Center from 1981 to 1990 was performed to investigate the changes in histologic types and the relationship to smoking history. The most frequent histologic type of lung cancer was squamous cell carcinoma (956 patients, 54.0%) followed by adenocarcinoma (311 patients, 17.6%) in males (1772 patients), and adenocarcinoma (206 patients, 45.1%) followed by squamous cell carcinoma (126 patients, 27.6%) in females (457 patients). In both sexes, the predominant type was adenocarcinoma under the age of 40, whereas squamous cell carcinoma was the most frequent type above the age of 40. While squamous cell carcinoma decreased over 10 years (54.3% in 1981, 44.3% in 1990), adenocarcinoma showed a gradually increased incidence (17.0% in 1981, 28.3% in 1990) in both sexes, and the proportion of small cell carcinoma and large cell carcinoma remained unchanged. These changes in histologic type were more prominent in non-smokers. In conclusion, the increasing incidence of adenocarcinoma in both sexes, especially in non-smokers, suggests the possible presence of etiologic factors other than smoking, such as environmental pollution.

Solitary Lymph Node Metastasis in Gastric Cancer

The feasibility and diagnostic reliability of sentinel node (SN) biopsy for gastric cancer are still controversial. We studied the clinicopathological features and localization of solitary lymph node metastasis (SLM) in gastric cancer to provide useful information for use of the SN concept in gastric cancer. From 2000 to 2004, 3,267 patients with gastric cancer underwent D2 radical gastrectomy. The clinicopathological features of 195 patients with histologically proven SLM and the distribution of metastasized nodes were assessed. The incidence of SLM was 6.0% in all cases. Compared with the node-negative patients, significant differences were observed in age, tumor size, depth of invasion, and surgical type. The cumulative 5-year survival rate of patients with SLM was 80.5%, which was significantly lower than 90.2% for node-negative patients (P < 0.001). Of patients with SLM, 82.6% had it in the perigastric node area (N1), and the other 17.4% patients had skip metastasis in the N2-N3 nodes. Perigastric nodes were the most common first sites of drainage from the tumor, making them the main targets of the operative SN mapping procedure. Due to the higher than expected incidence of skip metastasis in gastric cancer, D2 lymphadenectomy should be performed until the reliability of SN navigation surgery is validated in multicenter prospective clinical trials.

Value of Nonvisualized Primary Lesions of Gastric Cancer on Preoperative MDCT

OBJECTIVE The purpose of this study was to retrospectively determine the value of nonvisualized primary lesions on preoperative MDCT of patients with gastric cancer. MATERIALS AND METHODS The records of patients who had undergone radical gastrectomy for gastric cancer between August 2004 and August 2006 were retrospectively reviewed. Each patient was given 500-1,000 mL of water to drink, and 16-MDCT for preoperative staging was performed with i.v. contrast agents. Transverse and coronal reconstructed images had been prospectively interpreted as a part of daily practice. TNM stage, gross and histologic types, and location and size of the lesions were retrospectively analyzed for patients with primary lesions not visualized on preoperative MDCT. RESULTS In 44 patients with nonvisualized primary lesions, most (98%) of the lesions were stage pT1 confined to the mucosa (n = 27) or involving the submucosal layer (n = 16). Only one (2%) of the lesions had regional lymph node metastasis (pN1). Most (64%) of the lesions were located in the lower third of the stomach. Forty-one early gastric cancer lesions were flat, depressed, or excavated, and only two were elevated. Depending on the depth of invasion (mucosa or submucosa), there were no statistical differences (p > 0.05) in size, location, and gross or histologic type. CONCLUSION Almost all primary lesions of gastric cancer not visualized on preoperative MDCT with an optimized imaging protocol are early gastric cancer without regional lymph node metastasis. This negative finding may be helpful in planning minimally invasive management of gastric cancer.

Lymph node dissection around the splenic artery and hilum in advanced middle third gastric carcinoma.

AIM To evaluate the clinicopathological factors influencing lymph node metastasis around the splenic artery and hilum and the effect of spleen-preserved lymphadenectomy in advanced middle third gastric carcinoma. METHODS We retrospectively studied 131 patients with advanced middle third gastric carcinoma who had received D2 lymphadenectomy and lymph node dissection around the splenic artery and hilum, from 2000 to 2004. Of these patients, 62 simultaneously underwent splenectomy and 69 underwent spleen-preserved lymphadenectomy. RESULTS The incidences of Nos. 10 and 11 lymph node metastases were 21% and 15%, respectively, in advanced middle third gastric carcinoma. A tumor size larger than 5 cm, metastases of Nos. 1 and 7-9 lymph node were independent risk factors for metastasis of No. 10 and/or No. 11 lymph node. The spleen-preserved group had a slightly better survival rate and a relatively lower rate of postoperative complications than the splenectomy group. No. 10 and/or No. 11 lymph node metastasis was an independent prognostic factor, while splenectomy was not. CONCLUSIONS It is necessary to remove the lymph nodes around the splenic artery and hilum to achieve radical resection in advanced middle third gastric carcinoma patients with risk factors. Our results demonstrate that spleen-preserved lymphadenectomy is a good option for those patients.

Long-surviving patients with recurrent GIST after receiving cytoreductive surgery with imatinib therapy.

In the treatment of recurrent or metastatic gastrointestinal stromal tumors (GIST), good prognoses may not be expected by surgery alone. Recently, imatinib has been applied for the treatment of GISTs, resulting in improved patient survival. However, long-term success is limited due to the development of resistance. Herein, we report two cases of long-surviving patients with recurrent GIST after receiving cytoreductive surgery with imatinib therapy. A 49 year-old man was diagnosed to a duodenal GIST with single hepatic metastasis, and an antrectomy including the duodenal lesion with intraoperative radiofrequency ablation were performed in April, 2002. After four months, a new metastatic hepatic lesion was identified. Percutaneous radiofrequency ablation was done, and imatinib therapy was started. A 56 year-old man underwent laparoscopic segmental resection of the distal ileum and partial excision of parietal peritoneum in March, 2001 to treat a malignant GIST of the distal ileum that was attached to parietal peritoneum. After six months, recurrence of GIST with peritoneal seeding and hepatic metastasis was found, and he underwent cytoreductive surgery including right hemicolectomy and wedge resection of liver. After surgery, there was no residual tumor grossly and imatinib therapy was started. In both cases, they were doing well with no evidence of recurrence for 5 years with imatinib therapy. Therefore, in patients with a recurrent GIST, improved survival can be expected with imatinib therapy after cytoreductive surgery.

Effect of belly board with bladder compression device on small bowel displacement from the radiotherapy field for rectal cancer

Background: The aim of this study was to investigate the effect of a belly board (BB) with the addition of a bladder compression device (BCD) for small bowel (SB) displacement from the radiotherapy field for rectal cancer. Patients and Methods: Computed tomography (CT) scans of 38 rectal cancer patients positioned on a BB were analyzed and compared with CT scans from the same patients after the addition of a BCD. The BCD moves the inferior border of the BB from the pubic symphysis to the lumbosacral junction. The treated and irradiated volumes of the SB and bladder were compared. The irradiated volume ratio of SB to abdominopelvic cavity (APC) and that of bladder to APC were analyzed. Results: With the BCD, the treated and irradiated volumes of SB decreased significantly (49.1 ± 48.0 vs. 60.9 ± 50.9 cc, p = 0.006 and 207.5 ± 140.8 vs. 482.8 ± 214.2 cc, p < 0.001, respectively). The irradiated volume ratio of bladder to APC with the BCD increased considerably compared to that without the BCD (25.2 ± 11.5 vs. 18.7 ± 10.5%, p < 0.001), and the ratio of irradiated volume of SB to APC decreased significantly with the BCD (18.8 ± 12.4 vs. 31.8 ± 12.1%, p < 0.001). Conclusion: This study showed that the addition of a BCD to the BB could effectively provide further displacement of SB from the rectal cancer radiotherapy field.