Characteristics of gastric carcinoma invading the muscularis propria

Comparison between superficial muscularis propria and deep muscularis propria infiltration in gastric cancer patients: A retrospective cohort study

This study aimed to investigate the clinicopathological characteristics and survival outcomes of the subclassification of pT2 gastric cancers according to the depth of tumor involvement. We retrospectively collected clinicopathological data and survival outcomes for pT2 gastric cancer patients from 2006 to 2011. Patients were classified into the superficial muscularis propria (sMP) and deep muscularis propria (dMP) groups. Eighty-nine patients had sMP gastric cancers and 90 patients had dMP gastric cancers. The rates of lymph node metastasis for the sMP and dMP groups were 55.1% and 64.4%, respectively, P = 0.202. The 5-year overall survival (OS) of patients in the sMP group was significantly better than patients in the dMP group (76% vs 61%, P = 0.018). Multivariate analysis demonstrated that the depth of tumor invasion, lymph node metastasis, and postoperative chemotherapy were prognostic risk factors for the OS. For patients with pN0 stage tumor(s), the sMP group had a significantly better 5-year OS rate than the dMP group (92% vs 62%, P = 0.004); for patients with pN1-N3 stages, the 5-year OS rates were comparable between the sMP and dMP groups (64% vs 61%, P = 0.540). The subclassification of pT2 gastric cancer into the sMP and dMP groups can demonstrate different survival outcomes according to the lymph node status. However, the pT2 stage subclassification in the next tumor, node, metastasis (TNM) staging system is pending and requires more large sample size studies to confirm its importance.

Improved survival after adding dissection of the superior mesenteric vein lymph node (14v) to standard D2 gastrectomy for advanced distal gastric cancer

BACKGROUND

Extended lymph node dissection in gastric cancer (D3) was proven to have no survival benefit compared with a D2 dissection, but whether adding the superior mesenteric nodes (No. 14v) to the dissection provides survival benefit for gastric cancer patients remains controversial.

METHODS

From April 2001 to June 2007, 1,661 patients underwent curative resection for middle or lower third gastric cancer. Patients were grouped according to No. 14v lymphadenectomy (14vD+/14vD-). Clinicopathologic characteristics and treatment-related factors were compared between the groups. Overall survival according to the clinical stage (Union for International Cancer Control tumor-node-metastasis staging 6th edition) was analyzed using the Cox proportional hazard model.

RESULTS

The incidence of No. 14v lymph node metastasis was 5.0%. There was no difference in morbidity or mortality between the 14vD+ and the 14vD- groups. The proportion of locoregional recurrence was greater in 14vD- group (P = .018). In clinical stages I and II, 14v lymph node dissection did not affect overall survival; in contrast, 14v lymph node dissection was an independent prognostic factor in patients with clinical stage III/IV gastric cancer (hazard ratio, 0.58; 95% confidence interval, 0.38-0.88; P = .01).

CONCLUSION

Extended D2 gastrectomy including No. 14v lymph node dissection seems to be associated with improved overall survival of patients with clinical stage III/IV gastric cancer in the middle or lower third of the stomach.

Systematic review and meta-analysis of laparoscopic and open gastrectomy for advanced gastric cancer

Background

The use of laparoscopic gastrectomy (LG) in advanced gastric cancer (AGC) remains a controversial topic, mainly because of doubts about its oncologic validity. This study is a systematic review and meta-analysis of the available evidence.

Methods

A comprehensive search was performed until June 2013 to identify comparative studies evaluating survival rates, recurrence rates, surgical outcomes and complications. Pooled risk ratios (RR) and weighted mean differences (WMD) with 95% confidence intervals (CI) were calculated using the random effects model. Data synthesis and statistical analysis were carried out using RevMan 5.1 software.

Results

Fifteen trials were involved in this analysis. Compared to open gastrectomy (OG), LG involved a longer operating time (WMD = 48.67 min, 95% CI 34.09 to 63.26, P < 0.001); less blood loss (WMD = −139.01 ml, 95% CI −174.57 to −103.44, P < 0.001); earlier time to flatus (WMD = −0.79 days, 95% CI −1.14 to −0.44, P < 0.001); shorter hospital stay (WMD = −3.11 days, 95% CI −4.13 to −2.09, P < 0.001); and a decrease in complications (RR = 0.74, 95% CI 0.61 to 0.90, P = 0.003). There was no significant difference in the number of harvested lymph nodes, margin distance, mortality, cancer recurrence rate and long-term survival rate between the AGC patients treated with LG or OG (P > 0.05).

Conclusions

Despite a longer operation, LG is a safe technical alternative to OG for AGC with a lower complication rate and enhanced postoperative recovery. Moreover, there were similar outcomes between both approaches in terms of cancer recurrence and the long-term survival rate. Because of the limitation of this study, methodologically high-quality studies are needed for further evaluation.

Comparação da sobrevivência e dos fatores prognósticos em pacientes com adenocarcinoma gástrico T2 e T3

OBJETIVO: Comparar a sobrevivência e os fatores prognósticos, após o tratamento cirúrgico de pacientes com adenocarcinoma gástrico que compromete a camada muscular própria (T2), e de pacientes cujo tumor invade a subserosa (T3). MÉTODOS: Estudo retrospectivo de 122 pacientes com câncer gástrico invadindo a muscular própria e subserosa, submetidos ao tratamento cirúrgico no período de janeiro de 1997 a dezembro de 2008 e acompanhados até dezembro de 2010. Foram analisadas variáveis demográficas, cirúrgicas e anatomopatológicas. RESULTADOS: Dos 122 pacientes, 22 (18%) foram excluídos da análise final porque apresentaram: margem positiva, mortalidade pós-operatória, segundo tumor primário e menos de 15 linfonodos na peça cirúrgica. Entre os 100 pacientes incluídos, 75 apresentavam tumores com invasão da muscular própria (T2) e 25 com invasão da subserosa (T3). A sobrevivência global foi 83,8%, sendo 90,6% no T2 e 52,1% no T3. Na análise univariada apresentaram significância: metástase linfonodal (p=0,02), tamanho do tumor (p=0,000), estadiamento patológico do tumor (p=0,000), estadiamento patológico linfonodal (p=0,000) e estadiamento por grupos da classificação TNM-UICC/AJCC, 2010 (p=0,000) Na análise multivariada, os fatores prognósticos independentes foram o tamanho do tumor e o estadiamento patológico linfonodal (pN). CONCLUSÃO: O comprometimento linfonodal e o tamanho do tumor são fatores prognósticos independentes nos tumores com invasão da muscular própria e nos tumores com invasão da subserosa. O T2 apresenta menor tamanho, menor taxa de linfonodos metastáticos e consequentemente, melhor prognóstico que o T3.

Comparative study of laparoscopy-assisted versus open subtotal gastrectomy for pT2 gastric cancer

PURPOSE

Laparoscopy-assisted distal gastrectomy (LADG) is a widely accepted surgery for early gastric cancer. However, its use in advanced gastric cancer has rarely been studied. The aim of this study is to investigate the feasibility and survival outcomes of LADG for pT2 gastric cancer.

MATERIALS AND METHODS

Between January 2004 and December 2009, we evaluated 67 and 52 patients who underwent open distal gastrectomy (ODG) and LADG, respectively, with diagnosis of pT2 gastric cancer. The clinicopathological characteristics, postoperative outcomes, and survival were retrospectively compared between the two groups.

RESULTS

There were statistically significant differences in the proximal margin of the clinicopathological parameters. The operation time was significantly longer in LADG than in ODG (207.7 vs. 159.9 minutes). There were 6 (9.0%) and 5 (9.6%) complications in ODG and LADG, respectively. During follow-up periods, tumor recurrence occurred in 7 (10.4%) patients of the ODG and in 4 (7.7%) patients of the LADG group. The 5-year survival rate of ODG and LADG was 88.6% and 91.3% (p=0.613), respectively. In view of lymph node involvement, 5-year survival rates were 96.0% in ODG versus 97.0% in LADG for patients with negative nodal metastasis (p=0.968) and 80.9% in ODG versus 78.7% in LADG for those with positive nodal metastasis (p=0.868).

CONCLUSION

Although prospective study is necessary to compare LADG with open gastrectomy for the treatment of advanced gastric cancer, laparoscopy-assisted distal gastrectomy might be considered as an alternative treatment for some pT2 gastric cancer.

Safety of intraperitoneal administration of paclitaxel after gastrectomy with en-bloc D2 lymph node dissection

BACKGROUND

The aim of this study was to examine the safety, pharmacokinetics, and cytological efficacy against free intraperitoneal cancer cells of intraperitoneal chemotherapy (IPC) with paclitaxel after gastrectomy with en-bloc D2 lymph node dissection (GD2) in cases of gastric cancer with peritoneal carcinomatosis (PC) and/or positive cytological findings in peritoneal washings (CFPW).

METHODS

Twenty-one patients with gastric cancer with PC and/or positive CFPW who underwent GD2 were treated with early, post-operative, intraperitoneal paclitaxel. Intra-chemotherapeutic toxicity and operative complication were measured using the common toxicity criteria of the National Cancer Institute, version 3.0. Intraperitoneal and plasma paclitaxel concentrations were measured using a high-performance liquid chromatography assay.

RESULTS

Grade 3 anemia occurred in two patients (9.5%) and neutropenia was observed in three patients (14.3%). No grade 4 toxicity was observed. A grade 2 operative complication was a superficial surgical site infection (4.8%) that was treated with antibiotics. Cytologically, no viable cancer cells were observed in the intra-abdominal fluid 24 hr after intraperitoneal administration of paclitaxel. The intraperitoneal/plasma area under the drug concentration-time curve (AUC) ratio was 596.9:1.

CONCLUSION

IPC with paclitaxel after GD2 is a safe and cytologically effective treatment modality for free intraperitoneal cancer cells. However, additional data are required to determine the effect on survival.

Clinicopathological Variables Associated with Lymph Node Metastasis and Prognostic Factors in pT2 Gastric Cancer

This retrospective study investigated the clinicopathological variables associated with lymph node metastasis and prognosis in 325 patients with pT2 gastric cancer in order to set out a foundation for the surgical management of this condition. Univariate and multivariate analyses identified factors that were predictive of lymph node metastasis. Cox regression analysis evaluated the effect of prognostic factors on survival. Tumour location, maximum tumour diameter, lymphatic invasion and total retrieved lymph nodes (tLN) were revealed as independent factors for lymph node metastasis in pT2a gastric cancer, whereas histological type, lymphatic invasion and tLN were associated with lymph node metastasis in patients with pT2b gastric cancer. Maximum tumour diameter, lymphatic invasion and metastatic lymph node (mLN) ratio, but not tLN, were independent prognostic factors in pT2a cancer. Maximum tumour diameter and mLN ratio, but not tLN, were independent prognostic factors in pT2b cancer. Overall, it is concluded that maximum tumour diameter and mLN ratio are important prognostic factors in pT2 gastric cancer.

Heterogeneous prognoses of patients with tumors invaded within muscularis propria according to tumor depth in the layers of the muscularis propria

BACKGROUND

The muscularis propria of the stomach is histologically divided into three layers; namely, the innermost oblique, the inner circular, and the outer longitudinal layers. In patients with gastric cancer the depth of tumor invasion has been reported to correlate with lymph node metastasis and prognosis. However, it is unclear whether the depth of tumor invasion in the muscularis propria has an effect on lymph node metastasis and prognosis.

METHODS

Fifty-nine gastric cancer patients with muscularis propria invasion were analyzed retrospectively. These patients were divided into two groups, the inner group, with invasion up to the inner circular layer; and the outer group, with invasion beyond the inner circular layer. The relationships between tumor invasion and clinicopathological factors and survival were evaluated.

RESULTS

Of the 59 patients, 34 were classified as the inner group, and 25 were classified as the outer group. The inner group had a significantly lower probability of lymph node metastasis (P = 0.0053) and a significantly better overall cancer-specific survival (P = 0.017) than the outer group.

CONCLUSION

Gastric cancers with muscularis propria invasion had heterogeneous prognoses according to the tumor depth in the muscularis propria layers.

Prognostic significance of subclassification of pT2 gastric cancer: a retrospective study of 847 patients

PURPOSE

To investigate the prognostic significance of subclassification of pT2 gastric cancers according to the nodal status.

METHODS

Clinicopathological characteristics and prognostic outcomes of 847 gastric cancer patients who received a gastrectomy between 1985 and 2003 were retrospectively evaluated based on the subclassification of pT2 stage (i.e. pT2a and pT2b).

RESULTS

Of the patients, 244 and 603 had pT2a and pT2b stage cancers, respectively. Patients with pT2a cancers had a significantly longer disease-specific 5-year survival rate than those with pT2b cancers (P<0.001). The prognosis was significantly better in patients with pT2a cancers than in patients with pT2b cancers at pN0, pN1 and pN2 (P=0.036, 0.021, and 0.019 respectively), but not pN3 stages (P=0.775). Multivariate analysis identified age, tumor location, pT stages, pN stages, and adjuvant chemotherapy as independent prognostic factors for pT2 gastric cancers. The survival rates were similar between pT2aN1 (stage II) and pT2bN0 (stage IB) cancers (P=0.604), and between pT2aN2 (stage IIIA) and pT2bN1 (stage II) cancers (P=0.936).

CONCLUSIONS

Subclassification of pT2 gastric cancers into pT2a or pT2b is of prominent prognostic significance, and thus it is recommended that the current stage grouping conventions include subclassification of pT2, in order to more accurately predict the prognosis of patients.