Soichi Tomimatsu

Surgical strategy for patients with gastric carcinoma with submucosal invasion. A multivariate analysis

Background. Early gastric cancer can be treated by endoscopic excision or simple wedge surgical resection. Standard gastrectomy often is advised if submucosal invasion is found, even though only 15–25% of these patients have lymph node metastases. In this study, the risk of lymph node involvement was examined by multivariate analysis to develop a simple discriminant function for surgical decision making in this setting.

Proposal of a risk score for recurrence in patients with curatively resected gastric cancer

In this study, 168 patients who underwent curative resection for gastric cancer with prognostic serosal invasion [ps(+)] and 150 without prognostic serosal invasion [ps(−)] were analyzed separately to determine the prognostic importance of clinicopathological factors, and identify which patients were at high risk of recurrence. A multivariate analysis of survival time using Coxs proportional hazard model revealed the important prognostic factors to be: Lymph node involvement, the classification of gross appearance, macroscopic serosal invasion, and interstitial connective tissue in the ps(+) group; and lymph node involvement, macroscopic serosal invasion, and venous invasion in the ps(−) group. We proposed a risk score of recurrence based on the results of a further multivariate analysis called Hayashis Quantification Analysis II, in which recurrence was chosen as an objective variable and the above prognostic factors were chosen as explanatory variables. Eighty-four percent of the patients with a score of 0 or higher in the ps(+) group and 83% of those with a score of +6 or higher in the ps(−) group showed recurrence. Thus, we believe that this score is useful for identifying those patients at high risk of recurrence, who should receive intensive chemotherapy even after curative resection.

Relationship Between Nodal Stage and the Number of Dissected Perigastric Nodes in Gastric Cancer

To evaluate the rationality of the current nodal staging system in gastric cancer, we retrospectively analyzed 152 patients with perigastric node involvement localized to a single station, in whom the route of metastasis to distant nodes was limited. No significant differences in pathology or survival were observed between patients with stage n1 and those with stage n2–3 nodal involvement, but the mean (standard deviation) number of perigastric nodes dissected was 22.6 (12.6) in those with stage n1 involvement and 18.5 (9.5) in those with stage n2-3 involvement (P=0.04). When perigastric node involvement was localized to station 3, the mean number of dissected station 3 nodes was 7.7 (4.2) in n1 patients and 5.3 (2.8) in n2-3 patients (P=0.04). This tendency was also observed in patients with perigastric node involvement limited to either station 1 (P=0.08) or station 6 (P=0.11). Thus, patients with fewer perigastric nodes may have more lymphatics that bypass perigastric nodes and empty directly into distant nodes, increasing the likelihood of skip metastases. The number of positive nodes, affected to a lesser degree by lymphatic distribution than the location of positive nodes, should be incorporated into the staging criteria.

Effect of Blood Transfusions on Survival after Curative Resection for Advanced Gastric Cancer.

手術前後の輸血が胃癌切除後の予後と関連するか否かを検討した.教室における初発進行胃癌治癒切除症例を入院中の輸血たついて非輸血群144例,輸血量1,000ml未満の少量輸血群72例,1,000ml以上の大量輸血群69例に分けて比較すると,大量輸血群の生存率は非輸血群に比べ有意に低かった.両群間に進行程度の差がみられたため因子別に検討すると,深達度漿膜下層(ss)以上の症例およびリンパ節転移がないか1群までの症例で大量輸血群の生存率が非輸血群に比べ低かった.ss以上の症例では両群間に深達度,リンパ節転移の差はなかった.さらにss以上の症例について生存率に関与しうる11の臨床病理学的因子を選びCoxの比例ハザードモデルによる解析を行うと,周術期の輸血はリンパ節転移,腫瘍最大径,静脈侵襲とならんで有意に予後と関連していた.以上より進行胃癌治癒切除例,特に深達度ss以上の症例では周術期における輸血が切除後の生存率を悪くする可能性が示唆された.