Incidence and prognosis of N4 node involvement in gastric cancer

Pathological response measured using virtual microscopic slides for gastric cancer patients who underwent neoadjuvant chemotherapy

BACKGROUND

Although pathological response is a common endpoint used to assess the efficacy of neoadjuvant chemotherapy (NAC) for gastric cancer, the problem of a low rate of concordance from evaluations among pathologists remains unresolved. Moreover, there is no globally accepted consensus regarding the optimal evaluation. A previous study based on a clinical trial suggested that pathological response measured using digitally captured virtual microscopic slides predicted patients’ survival well. However, the pathological concordance rate of this approach and its usefulness in clinical practice were unknown.

AIM

To investigate the prognostic utility of pathological response measured using digital microscopic slides in clinical practice.

METHODS

We retrospectively evaluated pathological specimens of gastric cancer patients who underwent NAC followed by surgery and achieved R0 resection between March 2009 and May 2015. Residual tumor area and primary tumor beds were measured in one captured image slide, which contained the largest diameter of the resected specimens. We classified patients with < 10% residual tumor relative to the primary tumorous area as responders, and the rest as non-responders; we then compared overall survival (OS) and relapse-free survival (RFS) between these two groups. Next, we compared the prognostic utility of this method using conventional Japanese criteria.

RESULTS

Fifty-four patients were evaluated. The concordance rate between two evaluators was 96.2%. Median RFS of 25 responders and 29 non-responders was not reached (NR) vs 18.2 mo [hazard ratio (HR) = 0.35, P = 0.023], and median OS was NR vs 40.7 mo (HR = 0.3, P = 0.016), respectively. This prognostic value was statistically significant even after adjustment for age, eastern cooperative oncology group performance status, macroscopic type, reason for NAC, and T- and N-classification (HR = 0.23, P = 0.018). This result was also observed even in subgroup analyses for different macroscopic types (Borrmann type 4/non-type 4) and histological types (differentiated/undifferentiated). Moreover, the adjusted HR for OS between responders and non-responders was lower in this method than that in the conventional histological evaluation of Japanese Classification of Gastric Carcinoma criteria (0.23 vs 0.39, respectively).

CONCLUSION

The measurement of pathological response using digitally captured virtual microscopic slides may be useful in clinical practice.

Questionnaire survey regarding the current status of super-extended lymph node dissection in Japan

AIM

To verify the current status of super-extended lymph node dissection for advanced gastric cancer according to a questionnaire survey.

METHODS

One-hundred and five institutions responded to the questionnaire. The survey included the following items: Number of experiences, whether performed prophylactically and/or therapeutically, whether preoperative chemotherapy was provided, number of preoperative chemotherapy rounds, and therapeutic options after chemotherapy.

RESULTS

Eighty-seven of the 105 institutions (83%) had performed D3 gastrectomy in the past or continued to perform D3 gastrectomy at present. However, D3 gastrectomy was rarely performed prophylactically in clinical practice. Seventy-eight institutions (74%) indicated that preoperative chemotherapy with curative intent was required for patients suspected of having para-aortic node (PAN) metastases. After chemotherapy, a D3 gastrectomy was scheduled for patients with a complete or partial response, stable disease, and progressive disease at 36 (46%), 28 (36%), and 13 (17%) of the institutions, respectively.

CONCLUSION

For patients with apparent PAN metastasis, a D3 gastrectomy is typically planned if a few courses of preoperative chemotherapy yield at least a stable disease condition.

The clinical significance of para-aortic nodal dissection for advanced gastric cancer

BACKGROUND

Advanced gastric cancer with the risk of extensive nodal involvement has a poor prognosis even after radical surgery. We aimed to comprehensively review the clinical significance of extended radical dissection.

METHODS

Between 1990 and 1999, 232 patients underwent radical gastrectomy with D2 plus para-aortic lymph node dissection at the National Cancer Center Hospital in Tokyo. We analyzed the short-term surgical and long-term oncological outcomes of these operations.

RESULTS

Major complications occurred in 34 patients (14.7%). Median operation time was 325 min (range: 182-555) and median blood loss was 715 ml (range: 95-4457). There were 2 (0.9%) hospital deaths. Nodal involvement of the para-aortic area was seen in 33 patients (14.2%). The overall 5- and 10-year survival rates in patients with para-aortic node involvement were 21.2 and 15.2%, respectively. Multivariate analysis of patients with para-aortic node involvement revealed advanced age and metastasis in the interaorticocaval lymph nodes above the left renal vein to be independent risk factors impacting overall survival.

CONCLUSIONS

PAN dissection has limited applicability and effectiveness to the patients with advanced gastric cancer. Above all, advanced age and metastasis in the interaorticocaval lymph nodes above the left renal vein are significant poor prognostic factor even after radical resection.

Validity of response assessment criteria in neoadjuvant chemotherapy for gastric cancer (JCOG0507-A)

BACKGROUND

Neoadjuvant chemotherapy may improve outcomes in gastric cancer. Tumor responses can be evaluated with RECIST, Japanese Classification of Gastric Carcinoma (JCGC), and histological criteria. These approaches have not yet been compared.

METHODS

We analyzed two phase II trials of neoadjuvant chemotherapy using S-1 plus cisplatin. JCOG0210 included patients with linitis plastica and large ulcero-invasive tumors, whereas JCOG0405 comprised those with para-aortic or bulky lymph node metastases. Radiologic evaluations were conducted using RECIST in JCOG0405 and JCGC criteria in JCOG0210, because the latter included many patients without measurable lesions. A histological responder was defined as a patient in whom one third or more of the tumor was affected. The hazard ratios (HR) for death between responders and non-responders and response rate differences between short- and long-term survivors were estimated.

RESULTS

In JCOG0210 (n = 49), HR was 0.54 in JCGC responders (P = 0.059) and 0.40 in histological responders (P = 0.005). The difference in response rates between short- and long-term survivors using histological criteria (34 %, P = 0.023) was greater than that using JCGC criteria (24 %, P = 0.15). In JCOG0405 (n = 51), HR was 0.67 in RECIST responders (P = 0.35) and 0.39 in histological responders (P = 0.030). In short- and long-term survivors, respectively, RECIST response rates were 62  and 67 % (P = 0.77), whereas histological response rates were 33  and 63 % (P = 0.048).

CONCLUSIONS

Histological criteria showed higher response assessment validity than RECIST or JCGC criteria and yielded the best surrogate endpoint for overall survival.

Phase II study of neoadjuvant chemotherapy and extended surgery for locally advanced gastric cancer

BACKGROUND

Locally advanced gastric cancer with extensive lymph node metastasis is usually considered unresectable and so treated by chemotherapy. This trial explored the safety and efficacy of preoperative chemotherapy followed by extended surgery in the management of locally advanced gastric adenocarcinoma.

METHODS

Patients with gastric cancer with extensive lymph node metastasis received two or three 28-day cycles of induction chemotherapy with irinotecan (70 mg/m(2) on days 1 and 15) and cisplatin (80 mg/m(2) on day 1), and then underwent gastrectomy with curative intent with D2 plus para-aortic lymphadenectomy. Primary endpoints were 3-year overall survival and incidence of treatment-related death.

RESULTS

The study was terminated because of three treatment-related deaths when 55 patients had been enrolled (mortality rate above 5 per cent). Two deaths were due to myelosuppression and one to postoperative complications. Clinical response and R0 resection rates were 55 and 65 per cent respectively. The pathological response rate was 15 per cent. Median overall survival was 14.6 months and the 3-year survival rate 27 per cent.

CONCLUSION

This multimodal treatment of locally advanced gastric cancer provides reasonable 3-year survival compared with historical data, but at a considerable cost in terms of morbidity and mortality.

Stage migration caused by D2 dissection with para-aortic lymphadenectomy for gastric cancer from the results of a prospective randomized controlled trial

BACKGROUND

Extended lymphadenectomy (D2) provides accurate nodal staging of gastric cancer. The aim of this study was to clarify the degree of stage migration seen with D2 combined with para-aortic lymph node dissection for gastric cancer invading the subserosa, the serosa and adjacent structures (T2ss-4) in patients considered not to have distant metastases (M0).

METHODS

Between July 1995 and April 2001, 523 patients were recruited and randomized in a prospective phase III trial comparing D2 with D2 and para-aortic nodal dissection for T2ss-4 gastric cancer without macroscopic para-aortic nodal metastases. Stage migration was evaluated by Japanese Gastric Cancer Association staging in 260 patients who underwent D2 with para-aortic dissection by analysing pathological information from the dissected lymph nodes.

RESULTS

Node (N)-stage migration was observed in 1 per cent (1 of 82) of patients with N1 disease, 20 per cent (12 of 59) with N2, 43 per cent (10 of 23) with N3 and 8.8 per cent (23 of 260) of all patients. Final stage migration occurred in 9 per cent (5 of 58) of patients with stage IIIa, 19 per cent (8 of 42) with stage IIIb, 56 per cent (9 of 16) with stage IVa and 8.5 per cent (22 of 260) of all patients. Metastasis to N4 nodes was found in 4 per cent (four of 95) of tumours invading the subserosa and 17.4 per cent (19 of 109) of tumours penetrating the serosa. The overall incidence of N4 involvement was 8.8 per cent (23 of 260).

CONCLUSION

Extended para-aortic lymphadenectomy for gastric cancer provides accurate nodal staging and results in stage migration, which may improve stage-specific survival regardless of overall survival benefit.

Surgical treatment of gastric cancer invading the oesophagus

INTRODUCTION

There is controversy regarding which type of surgical treatment is most appropriate for upper gastric cancer invading the oesophagus.

METHODS

A review of the pertinent literature was carried out regarding oesophageal involvement in gastric cancer.

RESULTS

Invasion of the oesophagus occurred in 26-63% of Western surgical series. It was more frequent in Borrmann IV type, linitis plastica, pT3-pT4, diffuse type by Lauren, N+ or tumours exceeding 5 cm in diameter. Lymphatic tumour spread was caudad (coeliac nodes, hepatoduodenal nodes, paraortic nodes) but mediastinal nodes were also involved if tumour growth in the oesophagus exceeded 3 cm or if there was transmural oesophageal infiltration. In Western countries there was less than 30% 5-year survival and no long-term survivors when hepatoduodenal or mediastinal nodes were metastatic. Mediastinal dissection through thoracotomy did not provide any benefit.

CONCLUSIONS

A rational approach involves total gastrectomy plus partial oesophagectomy. Abdominal transhiatal resection may be performed in the case of a localized, non-infiltrating tumour and oesophageal involvement <2 cm. However, infiltrating, poorly differentiated or Borrmann III-IV tumours require a right thoracotomy to achieve a longer margin of clearance. When oesophageal involvement is >3 cm, or hepatoduodenal or mediastinal nodes are positive, no surgical procedure is curative and the literature demonstrates that extended aggressive surgery has no benefits.

Disease-free survival for 6 years and 4 months after dissection of recurrent abdominal paraaortic nodes (no. 16) in gastric cancer: report of a case

We herein report the case of a 63-year-old woman who underwent curative surgery consisting of a subtotal gastrectomy with D2 lymph node dissection for advanced stomach cancer in June 1984, and later underwent systemic dissection of recurrent abdominal paraaortic lymph nodes by a retromesenteric approach in June 1989. Metastatic nodes were found in nos. 16b1 (interaorticocaval), 16b2 (interaorticocaval), and 280 (aortic carinal). One of the resected nodes, which was histologically diagnosed as being poorly differentiated adenocarcinoma, measured approximately 10 x 7 cm and infiltrated the inferior caval vein. There was no distant metastasis except for nodal metastases. Since the reoperation, the patient has been disease-free for 6 years and 4 months, and she continues to visit our hospital as an outpatient. The findings of this case therefore suggest the significance of paraaortic lymph node dissection. To our knowledge, this is the first report in the world of a gastric cancer patient who has remained disease-free for more than 5 years after the systemic dissection of recurrent paraaortic lymph nodes.

Surgical results of performing R4 gastrectomy for gastric cancer located in the upper third of the stomach

Because gastric cancers located in the upper third of the stomach are difficult to detect at an early stage, the surgical results remain poor. We performed R4 gastrectomy as a radical procedure for 25 patients, involving complete resection of the latero-aortic and interaorticovenous lymph modes above and below the left renal vein, in combination with the ordinary R2 or R3 gastrectomy (the R4 group). These patients were compared with 156 others who underwent R2 gastrectomy alone (the R2 group). There were no significant differences in operation time, blood loss, or the incidence of complications between the two groups; however, when the survival rates of the patients with tumors invading beyond the subserosa were compared, the 5-year survival rate was found to be significantly higher in the R4 group than in the R2 group. Furthermore, in patients with para-aortic nodal involvement, a significant survival advantage was observed in the R4 group, as compared with the R2 group. These results suggest that the R4 gastrectomy is a rational approach for patients with advanced gastric cancer located in the upper third of the stomach.

Factors influencing noncompliance and contamination in a randomized trial of "Western" (r1) versus "Japanese" (r2) type surgery in gastric cancer

BACKGROUND

A randomized trial was undertaken comparing the Western R1 resection with limited N1-level lymphadenectomy and the Japanese R2 resection with extended lymphadenectomy, including the N2-level for curative resection of gastric cancer patients. After 389 patients were entered in the trial, protocol deviations were observed that reduced the intended distinction between the two types of lymphadenectomy: noncompliance, i.e., no substantiation of lymphadenectomy by nodal yields of indicated stations, and contamination, i.e., extension of lymphadenectomy outside the allocated level of nodal clearance.

METHODS

To identify factors underlying these protocol deviations, the authors analyzed the influence of six patient-, tumor, and treatment-related characteristics on the magnitude of deviations per patient, and on the incidence of deviations per lymph node station.

RESULTS

Protocol deviations were influenced by the following station-specific factors: (1) the number of nodes per station; (2) the clarity of anatomical station definition; (3) the location of stations; (4) local conventions on the type of gastrectomy; and (5) technical features to allow complete en bloc dissection. Furthermore, nonspecific factors such as inadequate retrieval of nodes, incomplete dissection, and careful selection of clinically overt metastases outside the allocated level of nodal clearance were randomly distributed over stations, and they, too, contributed to the deviations.

CONCLUSIONS

Based on the findings, the authors took additional steps to preserve the distinction between limited and extended lymphadenectomy and to improve the accuracy of nodal staging. These factors should be considered when standardization of both surgicopathologic trials and clinical protocols for the treatment of gastric cancer is pursued.

Deacylation-reacylation cycle: a possible absorption mechanism for the novel lymphotropic antitumor agent dipalmitoylphosphatidylfluorouridine in rats

Dipalmitoylphosphatidylfluorouridine (DPPF) is a potent antitumor agent that selectively gains access to the lymphatic system. To determine whether DPPF enters the lymph in an unmodified form, we administered DPPF orally to rats and analyzed lymph collected from a cannula in the thoracic duct. Although lymph was found to contain only very low levels of DPPF, two congeners of DPPF were detected at high levels. Instrumental analysis demonstrated that these congeners are 1-palmitoyl-2-arachidonoylphosphatidylfluorouridine (PAPF) and 1-palmitoyl-2-linoleoyl-phosphatidylfluorouridine (PLPF). PAPF and PLPF levels in thoracic lymph were shown to be approximately 30 times higher than those in plasma. These results suggest that DPPF is absorbed from the intestinal tract via the deacylation-reacylation cycle for the uptake of phospholipids and is selectively delivered to the lymphatic route after oral administration. DPPF is a candidate drug for the treatment of tumor metastasis, especially in cases where metastasis has occurred via the lymphatic route.

Improving survival in gastric cancer: review of operative mortality in English language publications from 1970

In this review of English language publications from 1970, operative mortality following surgery for gastric cancer has been analysed. Operative mortality has declined in series reporting operations in successive decades to 1970, 1980 and 1990. Series reporting patients having surgery for gastric cancer in the decade to 1990 show a mean operative mortality rate of 7.8 per cent (median 4.6 per cent). This improvement may have contributed to the declining mortality rates for gastric cancer in the face of unchanging surgical workload. Results of operations for gastric cancer should be reported in a standard manner.

Number and size of perigastric lymph nodes in human adults without gastric cancer

For classification of perigastric lymph node metastases in gastric cancer, only topographical aspects are taken into consideration at present. As a numerical classification for lymph node metastases was proposed recently, the current problem is that of determining the number of dissectable perigastric lymph nodes and also assessing the quality of nodal dissection. The perigastric lymph nodes of 10 adults without gastric disease were therefore evaluated microscopically by a serial section technique. On average a total of 36.2 +/- 15.2 perigastric lymph nodes were found, e.g. 14.9 +/- 14.1 lymph nodes on the greater and 7.4 +/- 4.8 on the lesser curvature. These figures are similar to those in fetuses and newborn infants, but they exceed the numbers of perigastric lymph nodes reported in the literature for adults with or without gastric cancer. This difference could be attributable to our use of the serial section technique, because the so-called "micro-lymph nodes" with a diameter of less than 1.5 mm are consequently included in this study. Our results support the assumption, that pathologic processes do not result in any real increase of regional lymph nodes, but in an activation and enlargement of fetal lymph node reserve.

The survival benefit of resection in patients with advanced stomach cancer: the Norwegian multicenter experience. Norwegian Stomach Cancer Trial

Five hundred three of 1,165 patients with stomach cancer included in a national multicenter study received noncurative treatment. This study elucidates whether a palliative resection offered any survival advantage compared to nonresectional treatment. One hundred eighty-two (36%) of 503 patients had gastric resection (including total gastrectomy in 64 patients), 70 (14%) had a bypass procedure, and an exploratory laparotomy was carried out in 156 (31%). Seventy-eight patients (16%) were not subjected to surgery. Resection carried the same postoperative mortality rate as a nonresectional procedure (13% versus 12%). Univariate survival analysis demonstrated that median survival and 1- and 2-year survival rates were significantly higher in resected patients; however, as basic patient characteristics (age, stage, etc.) differed between the 2 main treatment groups, survival and factors affecting survival were analyzed using the Cox proportional hazards model. Given similar age and preoperative weight loss, resection doubled median survival both for stage III disease (9 versus 4.5 mo) and for stage IV disease (6 versus 3 mo) compared to nonresection or no operation. In conclusion, resection seems justified in patients with advanced stomach cancer since a survival benefit is documented.

Primary gastric lymphoma

This is a population-based review of 153 cases of primary gastric lymphoma. Sixty-seven (43 per cent) were histologically reviewed using the Kiel classification. There were no significant differences between reviewed and unreviewed cases. Ninety-seven per cent of all cases were of the non-Hodgkin's type. The annual incidence was constant at 1.2 per cent of gastric malignancies. The mean age was 60 years and the male to female ratio 1:8. Presenting symptoms were similar to those of gastric cancer. Twenty-one per cent had a palpable mass but one-third of these were amenable to a potentially curative resection. Some 66 per cent were resectable and 58 per cent had a macroscopic clearance of tumour. TNM stage and absolute tumour size were significant prognostic factors (P less than 0.005 and P less than 0.05 respectively) but the Kiel classification was not. The overall 5 year survival was 24 per cent. Apart from 10 patients whose only anti-tumour treatment was radiotherapy (5 year survival 36.9 per cent) no patient who did not have curative surgery survived 5 years. The 5 year survival for curative resection was 34 per cent and for curative resection plus radiotherapy was 43.5 per cent (45 and 73.4 per cent for the node negative cases respectively). A laparotomy is essential; 'curative' surgery possibly with adjuvant radiotherapy offers the best hope for cure.