Different clinicopathologic features and prognostic significance of signet ring cell histology in early and locally advanced gastric cancer patients.

BACKGROUND: Although many studies have evaluated the prognostic significance of signet ring cell (SRC) histology for gastric cancer (GC) patients, the results were conflicting. The objective of this study was to compare clinicopathologic characteristics between SRC type and other types, and evaluate its impact on survival outcome. METHODS: We retrospectively reviewed clinicopathologic and survival data of 1891 patients who underwent curative resection for GC. All patients were divided into differentiated, undifferentiated and SRC type according to the histological classification. The prognostic differences between different types were compared and clinicopathologic factors were analyzed. RESULTS: SRC histology type had a poorer disease-free survival (DFS) than differentiated type (5-year DFS, 37.7% vs 52.2%, P<0.001), but there was no prognostic difference between SRC type and undifferentiated type (37.7% vs 41.9%, P>0.05). For early GC patients, SRC type was more frequent in younger, female patients and T1a stage tumors; the 5-year DFS of SRC type was similar to that of any other histology type (P>0.05). SRC type showed more aggressive biological features, including extensive stomach involvement, large tumor size, advanced pTstage and pN stage, than other types for locally advanced GC patients; poorer DFS was observed in SRC type compared with differentiated type. Multivariate analysis indicated that SRC type (HR:1.71, 95%CI:1.10-1.68, P<0.01) and undifferentiated type (HR:1.21, 95%CI:1.04-1.40, P<0.05) were independently associated with poor DFS in locally advanced GC patients. CONCLUSION: There was a significant difference between early and locally advanced GC patients with regard to clinicopathologic features and prognostic significance of SRC histology. SRC type was an independent prognostic factor for locally advanced GC patients, but not for early GC patients.

Risk of lymph node metastasis and prognostic outcome in early gastric cancer patients with mixed histologic type.

BACKGROUND: Whether early gastric cancer with mixed histologic type should be considered for endoscopic submucosal dissection (ESD) remains controversial. The objective of this study was to evaluate the risk of lymph node metastasis (LNM) and prognostic significance for early gastric cancer with mixed histologic type. METHODS: We retrospectively reviewed clinicopathologic and survival data of 302 patients who underwent surgical resection for early gastric cancer. Based on the histologic components, all patients were classified as pure differentiated type, pure undifferentiated type and mixed histologic type. The prognostic differences between different types were compared and predictive factors for LNM were evaluated. RESULTS: Histopathologically, the proportion of mixed histologic type was 12.3% in early gastric cancer. In terms of LNM, mixed histologic type had a more frequent incidence than pure differentiated type (32.4% vs 11.1%, P < 0.01). However, there was no significant difference between mixed type and pure undifferentiated type for LNM (32.4% vs 21.1%, P = 0.139). Multivariate analysis revealed that tumor size >2 cm (odds ratio [OR]: 2.153, 95% confidence interval [CI]: 1.113-4.164, P < 0.05), submucosal invasion (OR: 3.881, 95%CI: 1.832-8.222, P < 0.001), lymphovascular invasion (OR: 8.797, 95% CI: 2.643-29.277, P < 0.001), undifferentiated type (OR: 3.146, 95% CI: 1.352-7.320, P < 0.01), and mixed histologic type (OR: 3.635, 95% CI: 1.272-10.390, P < 0.05) were independent risk factors for LNM in early gastric cancer patients. However, mixed histologic type did not affect the survival outcome of these patients (hazard ratio: 0.629, 95% CI: 0.074-5.311, P > 0.05). CONCLUSION: Mixed histologic type was an independent risk factor for lymph node metastasis in early gastric cancer patients. The decisions regarding endoscopic submucosal dissection for mixed histologic type should be carefully considered.

Clinicopathological features, risk of lymph node metastasis and survival outcome of synchronous multiple early gastric cancer.

OBJECTIVE: To determine clinicopathological features, risk of lymph node metastasis (LNM) and survival outcome in synchronous multiple early gastric cancer (MEGC) patients. METHODS: A total of 338 solitary early gastric cancer (SEGC) and 26 MEGC patients who underwent surgical resection were retrospectively reviewed. The clinicopathological features and predictive factors for MEGC patients were evaluated. Also, we analyzed risk factors for LNM and compared survival difference between SEGC and MEGC patients. RESULTS: The frequency of multiple synchronous lesions was 7.1% in early gastric cancer (EGC) patients. The main and minor lesions were mostly confined to the same third of the stomach (84.6%, 22/26), and the most common location was the lower third of the stomach. With regard to the number of coexisting lesions, most of the patients had two lesions and more than three lesions were not common. Tumor size≤2cm (OR:2.684, 95%CI:1.131-6.368, P<0.05) and the presence of atrophic gastritis (OR:2.418, 95%CI:1.052-5.555, P<0.05) were independent risk factors for synchronous MEGC. There was no significant statistical difference between SEGC and MEGC for LNM (17.5% vs 23.1%, P=0.311). The number of coexisting lesions was not associated with the risk of LNM in EGC. In addition, the survival outcome of MEGC patients was similar to that of SEGC (5-year RFS rate, 96.0% vs 93.7%, P=0.329;5-year OS rate, 96.0% vs 88.3%, P=0.479). CONCLUSION: Meticulous endoscopic examination at the initial diagnosis of MEGC was very important, especially for those with precancerous lesions such as atrophic gastritis. In terms of treatment methods, endoscopic resection may be equally suitable for synchronous MEGC if the lesions fulfilled its indication criteria.

Clinicopathologic Features, Survival Outcome, and Prognostic Factors in Gastric Cancer Patients 18-40 Years of Age.

Purpose: Whether young patients with gastric cancer (GC) had a distinct prognostic outcome from older patients remains controversial. The objective of this study was to investigate the clinicopathologic characteristics and prognostic factors of young GC patients and evaluate the survival outcome in comparison to their older counterparts. Methods: We retrospectively reviewed clinicopathologic and survival data of 2022 patients who underwent curative resection for GC. All patients were divided into the young patient group (18-40 years) and older patient group (>40 years) according to the patient age. Clinicopathologic characteristics and prognostic factors of young GC patients were analyzed, and the survival difference between the two groups was compared. Results: The incidence of GC in the patients 18-40 years of age was 8.1% (164/2022). The young patient group had different clinicopathologic features from the older group, including a significant female predominance, a larger number of retrieved lymph nodes, a higher proportion of undifferentiated histology type, and middle or lower 1/3 GC. However, the survival outcome of young patients was similar to that of their older counterparts (5-year disease free survival [DFS]: 47.0% vs. 44.0%, p = 0.247), even when comparison based on the TNM stage was made. Deeper tumor invasion (T3-T4 stage, hazard ratios [HR]: 5.791, 95% confidence intervals [CIs]: 2.908-11.533, p < 0.001), lymph node metastasis (HR: 2.500, 95% CIs: 1.308-4.781, p = 0.006), and lymphovascular invasion (HR: 2.191, 95% CIs: 1.306-3.677, p = 0.003) were independent prognostic factors for young GC patients. Conclusions: Young age (18-40 years) was not associated with poorer survival outcome in GC patients. However, early diagnosis and curative resection with adequate lymphadenectomy will still be necessary for improving the survival outcome of young GC patients.

Perineural invasion as a predictive factor for survival outcome in gastric cancer patients: a systematic review and meta-analysis.

AIMS: The prognostic significance of perineural invasion (PNI) for gastric cancer (GC) patients was under debate. This study aimed to review relevant studies and evaluate the impact of PNI on the survival outcome of GC patients. METHODS: Systematic literature search was performed using PubMed and Embase databases. The relevant data were extracted, and the association between PNI and clinicopathological characteristics or survival outcome in GC patients were evaluated using a fixed-effect model or random-effect model. RESULTS: A total 13 studies involving 7004 GC patients were included in this meta-analysis. The positive rate of PNI was 35.9% (2512/7004) in GC patients, ranging from 6.9% to 75.6%. There were significant relationships between PNI and a series of unfavourable clinicopathological factors including undifferentiated histology type (OR: 1.78, 95% CI 1.37 to 2.33, p<0.001; I2=75.3%), diffuse type (OR: 1.96, 95% CI 1.07 to 3.60, p=0.029; I2=79.5%), lymphatic invasion (OR: 7.00, 95% CI 3.76 to 13.03, p<0.001; I2=83.6%), vascular invasion (OR: 5.79, 95% CI 1.59 to 21.13, p=0.008; I2=95.8%), deeper tumour invasion (OR: 4.79, 95% CI 3.65 to 6.28, p<0.001; I2=65.0%) and lymph node metastasis (OR: 3.60, 95% CI 2.37 to 5.47, p<0.001; I2=89.6%). In addition, PNI was significantly associated with worse survival outcome in GC patients (HR: 1.69, 95% CI 1.38 to 2.06, p<0.001; I2=71.0%). CONCLUSION: PNI was frequently detected in surgically resected specimens of GC patients, and it was a predictive factor for survival outcomes in these patients.

Comparison of short-term surgical outcome between 3D and 2D laparoscopy surgery for gastrointestinal cancer: a systematic review and meta-analysis.

BACKGROUND: Three-dimensional (3D) laparoscopic surgery is becoming more popular with the development of laparoscopic devices. The objective of this study was to explore whether the 3D imaging system could improve surgical outcomes of laparoscopic surgery for gastrointestinal cancer compared with the 2D imaging system. METHODS: Systematic literature search was performed using PubMed and Embase databases and relevant data were extracted. Surgical quality, postoperative complications, and postoperative recovery between 3D and 2D laparoscopic surgery groups were compared using a fixed or random effect model. RESULTS: A total of 12 studies involving 1456 patients (3D group 683 patients and 2D group 773 patients) were included in this meta-analysis. The results indicated that mean operation time was significantly shorter in 3D group than in 2D group (WMD, - 9.08; 95% CI, - 14.77, - 3.40; P = 0.002; I2 = 70.3%), especially for gastric cancer patients (WMD, - 14.61; 95% CI, - 26.00, - 3.23, P = 0.012; I2 = 74.1%). In addition, 3D laparoscopic surgery for gastric cancer had an advantage than 2D group in reducing the amount of intraoperative blood loss (WMD, - 13.60, 95% CI, - 21.48, - 5.72; P = 0.001; I2 = 0%). The number of retrieved lymph nodes in 3D group was not significantly different from that in 2D group, regardless of laparoscopic gastrectomy (WMD, 1.10; 95% CI, - 0.67, 2.88; P = 0.222; I2 = 18.8%) and laparoscopic colorectal surgery (WMD, 0.55, 95% CI; - 1.99, 3.09; P = 0.671; I2 = 76.9%). In addition, there was no significant difference between 3D and 2D laparoscopic surgery for postoperative complications and postoperative recovery. CONCLUSION: Main advantages of 3D laparoscopic gastrectomy for gastric cancer were that it could shorten the operation time and reduce the amount of intraoperative blood loss. However, 3D laparoscopic surgery had no obvious advantage over 2D laparoscopic surgery for colorectal cancer patients.

Impact of proximal resection margin involvement on survival outcome in patients with proximal gastric cancer.

AIM: The aim of this study was to evaluate the risk factors for proximal resection margin involvement and its impact on survival outcome in patients with proximal gastric cancer. METHODS: A total of 488 patients who underwent potentially curative resection for proximal gastric cancer were retrospectively reviewed. Clinicopathological characteristics and survival differences between patients with positive and negative resection margins were compared and prognostic factors were determined by Cox multivariate analysis. RESULTS: In this study, 7.6% (37/488) of patients with proximal gastric cancer had a positive proximal resection margin after postoperative histopathological examination. Positive resection margins were significantly associated with advanced tumour stage and more aggressive biological features including larger tumour size, serosal invasion and lymphovascular invasion. Serosal invasion (OR 4.543, 95% CI 2.201 to 9.380, p<0.001) and lymphovascular invasion (OR 2.279, 95% CI 1.129 to 4.600, p<0.05) were independent risk factors for positive proximal resection margins. In terms of survival outcome, positive resection margins had an adverse impact on the prognosis of patients with proximal gastric cancer (median DFS: 20.7 vs 30.2 months, p<0.001). The multivariate analysis indicated that positive resection margins (HR 1.494, 95% CI 1.042 to 2.142, p=0.029), T stage (T3-T4, HR 2.264, 95% CI 1.484 to 3.454, p<0.001) and N stage (N1-N2 stage, HR 1.696, 95% CI 1.279 to 2.248, p<0.001; N3 stage, HR 2.691, 95% CI 1.967 to 3.681, p<0.001) were independent prognostic factors for patients with proximal gastric cancer. CONCLUSION: Proximal resection margin involvement was an indicator of more aggressive tumours and an independent prognostic factor for patients with proximal gastric cancer. Aggressive efforts should be made to achieve a negative resection margin if gastric cancer was deemed to be potentially resectable.