Impact of skip metastasis in gastric cancer

Prognostic significance of common hepatic artery lymph node metastasis in gastric cancer

PURPOSE

The number of lymph nodes is used to determine the prognosis in patients with gastric cancer undergoing D2 lymph node dissection. However, a group of extraperigastric lymph nodes, including lymph node 8a, are also considered to be effective in prognosis. In our clinical experience, in most patients during D2 lymph node dissection, the lymph nodes are removed en-bloc with the specimen and are not marked separately. The aim was to analyze the importance and prognostic impact of 8a lymph node metastasis in patients with gastric cancer.

METHODS

Patients who underwent gastrectomy and D2 lymph node dissection for gastric cancer between 2015 and 2022 were included in the study. Patients were divided into two groups based on metastasis to the 8a lymph node: metastatic and nonmetastatic. The effect of clinicopathologic features and the prevalence of lymph node metastasis on the prognosis of the two groups were analyzed.

RESULTS

The present study included 78 patients. The mean number of dissected lymph nodes was 27 (IQR, 15-62). There were 22 (28.2%) patients in the 8a lymph node metastatic group. Patients with 8a lymph node metastatic disease had shorter overall survival and shorter disease-free survival. Those with metastatic 8a lymph nodes among pathologic N2/3 patients had shorter overall and disease-free survival rates (p < 0.05).

CONCLUSION

In conclusion, we believe that anterior common hepatic artery (8a) LN metastasis is a key factor that negatively affects both disease-free and overall survival in patients with locally advanced gastric cancer.

Central lymph node metastasis is predictive of survival in advanced gastric cancer patients treated with D2 lymphadenectomy

Background

The number of positive lymph nodes, which was defined as “N stage”, is mostly used to predict the survival of D2-resected gastric cancer patients, not the location. A “central lymph node” (CnLN) was defined by Ikoma et al., included common hepatic, celiac and proximal splenic artery LNs. CnLNs located in the extraperigastric area are included in the D2 LN station for gastric cancer. We speculate that CnLNs can be regarded as a predictor of survival.

Methods

Eligible advanced gastric cancer patients who underwent curative resection and D2 lymph node dissection between 2004 and 2012 at our institution were identified. The frequency of CnLN metastases and risk factors affecting DFS were examined. Survival differences were assessed by log-rank tests and Kaplan–Meier curves.

Results

The study identified 1178 patients who underwent curative surgery or D2 or more extensive lymphadenectomy. A total of 342 patients had been proven to have CnLN metastasis. Larger tumor size (P < 0.001), more frequent lymphatic vessel invasion (P < 0.001), signet ring cell histology (P = 0.014), and more advanced pathological T stage (P = 0.013) were significantly related to CnLNs metastasis. The patients with CnLN metastasis had a poor prognosis (HR for DFS of 1.366, 95%CI = 1.138–1.640, P = 0.001). For the pN2/3 patients, CnLN metastasis was associated with shorter 5-year DFS (for pN2 patients: 25.9% vs 39.3%, P = 0.017; for pN3 patients: 11.5% vs 23.4%, P = 0.005).

Conclusion

Gastric cancer patients with CnLN metastasis who underwent D2 resection had a poor prognosis. With the same N stage, the patients with positive CnLNs had shorter survival. CnLNs metastasis could be a supplement to N stage and a predictor of survival in gastric cancer patients. Large sample, multicenter, randomized clinical trials are still needed in the future.

A slowly-growing solitary skip lymph nodule of occult gastric cancer above the neck of pancreas: a case report

BACKGROUND

Skip lymphatic metastasis (SK) is an exceptional and characteristic pattern of lymph node metastasis in gastric cancer (GC) with infrequent incidence. This is an extremely rare report of occult gastric cancer with solitary skip lymphatic metastasis as the initial and primary observation.

CASE PRESENTATION

A 61-year-old woman, who complained of epigastric discomfort for several years, presented a solitary nodule upon pancreas neck examination by CT without performance on the primary lesion, even gastroscopy. During the preoperative 4-month follow-up, the nodule stayed stable without any therapy. The postoperative pathological examination confirmed the consistent diagnosis of gastric adenocarcinoma between the nodule and the stomach lesion, which was found by preoperative random biopsy of the mucosa.

CONCLUSIONS

This case highlights the concentration on vigilance to the SK of GC and a closer observation for intra-abdominal nodules, even radiological suspicion of a benign lesion.

Risk factors for lymph node metastasis in non-sentinel node basins in early gastric cancer: sentinel node concept

BACKGROUND

Sentinel node (SN) concept is being applied to early gastric cancer. However, when SNs are positive for metastasis, it is unclear how often LNs in other LN basins show metastasis. We aimed to investigate LN metastasis possibility in LN basins without SNs (non-SN basins). We determined risk factors for metastasis in non-SN basins and identified a prediction model for non-SN basin metastasis using classification and regression tree (CART) analysis.

METHODS

We enrolled 550 patients who were diagnosed with cT1N0M0 or cT2N0M0 gastric cancer with a single lesion and underwent SN mapping. We adopted a dual-tracer method using a radioactive colloid and blue dye to detect SNs.

RESULTS

Of all, 45 (8.2%) patients had SN metastasis; we divided them into two groups: LN metastasis positive and LN metastasis negative in non-SN basins. Univariate analysis showed that the groups differed significantly regarding lymphatic invasion (p = 0.007), number of identified SNs (p = 0.032), and macrometastasis in SN basins (p = 0.005). The CART decision tree for predicting LN metastasis in non-SN basins had area under the curve value of 0.86. Moreover, there were significantly differences in cancer-specific survival (CSS) between the two groups (p = 0.028).

CONCLUSIONS

Macrometastasis in SN basins, lymphatic invasion, and number of identified SNs ≥ 5 are risk factors for LN metastasis in non-SN basins among gastric cancer patients. We identified a prediction model with CART analysis; patients with macrometastasis in SN basins and lymphatic invasion were considered to be at the highest risk for LN metastasis.

Anatomical location of metastatic lymph nodes: an indispensable prognostic factor for gastric cancer patients who underwent curative resection

BACKGROUND

Although the numeric-based lymph node (LN) staging was widely used in the worldwide, it did not represent the anatomical location of metastatic lymph nodes (MLNs) and not reflect extent of LN dissection. Therefore, in the present study, we investigated whether the anatomical location of MLNs was still necessary to evaluate the prognosis of node-positive gastric cancer (GC) patients.

METHODS

We reviewed 1451 GC patients who underwent radical gastrectomy in our institution between January 1986 and January 2008. All patients were reclassified into several groups according to the anatomical location of MLNs and the number of MLNs. The prognostic differences between different patient groups were compared and clinicopathologic features were analyzed.

RESULTS

In the present study, both anatomical location of MLNs and the number of MLNs were identified as the independent prognostic factors (p < .01). The patients with extraperigastric LN involvement showed a poorer prognosis compared with the perigastric-only group (p < .001). For the N1-N2 stage patients, the prognostic discrepancy was still observed among them when the anatomical location of MLNs was considered (p < .05). For the N3-stage patients, although the anatomical location of MLNs had no significant effect on the prognosis of these patients, the higher number of MLNs in the extraperigastric area was correlated with the unfavorable prognosis (p < .05).

CONCLUSION

The anatomical location of MLNs was an important factor influencing the prognostic outcome of GC patients. To provide more accurate prognostic information for GC patients, the anatomical location of MLNs should not be ignored.

Skip lymph node metastasis in gastric cancer: is it skipping or skipped?

BACKGROUND

Skip metastasis is the presence of a metastatic lymph node (LN) in an extraperigastric (EP) area without perigastric (PG) involvement. The mechanism and prognosis of skip metastasis are still unknown. The purpose of this study was to scrutinize the clinical significance of skip metastasis in gastric cancer.

METHODS

Data were reviewed from 6,025 patients who had undergone gastrectomy for primary gastric cancer. Patients were categorized as a PG-only group when the metastatic LNs were limited to only the PG area, as a PG + EP group if metastatic LNs extended to both the PG area and the EP area, and as a skip group if metastatic LNs were in the EP area but there were no metastatic LNs in the PG area.

RESULTS

After we had performed matching, the prognosis of the skip group was worse than that of the PG-only group (adjusted hazard ratio 1.69, 95% confidence interval 1.13-2.54) and was similar to that of the PG + EP group (adjusted hazard ratio: 1.54, 95% confidence interval 0.92-2.59). The number of retrieved LNs was less in the skip group than in the other groups, especially from the PG area (p < 0.001).

CONCLUSIONS

The prognosis of the skip group was worse than that of the PG-only group and was similar to that of the PG + EP group when the tumor stage was considered. It is difficult to conclude whether skip metastasis is real skipping of cancer cells or a result of inadequate LN sampling. Further evaluation of LNs in the PG area of the skip group could provide more clues for the mechanism of skip metastasis.

The clinical significance and risk factors of solitary lymph node metastasis in gastric cancer

AIMS

To assess the clinical significance and risk factors of solitary lymph node metastasis (SLM) in gastric carcinoma and establish a more accurate method to evaluate the possibility of lymph node metastasis (LM).

METHODS

A total of 385 patients with gastric carcinoma who underwent D2 lymphadenectomy at the Cancer Center of Sun Yat-Sen University were included in this research. Then we used a group of data from Sun Yat-sen University Gastrointestinal Hospital (SYSUGIH) to validate the accuracy of our developed method. The χ2 test, Kaplan-Meier analysis, log-rank test, COX model, and discriminate analysis were used to analyze the data with SPSS13.0.

RESULTS

We found that the LM number and pathological T staging were independent prognostic risk factors. CEA grading, LN status by CT, and T staging by CT were independent risk factors for LM in gastric carcinoma. In addition, we developed the equation Y = -5.0 + X1 + 1.8X3 + 0.7X4 (X1 = CEA grading, X3 = LN status by CT, X4 = T staging by CT) to evaluate the situation of LM. The data from SYSUGIH shows this equation has a better accuracy compared with CT.

CONCLUSIONS

SLM is an independent risk factor in gastric cancer. And there was no survival difference between the skip metastasis group and the other SLM group (P = 0.659). It is inappropriate for the patient with SLM doing a standard D2 lymphadenectomy, due to the fact that LM rarely occurs in the splenic artery, splenic hilum. The risk factors for LM include CEA grading, LN status by CT, and T staging by CT. And we can use Y = -5.0 + X1 + 1.8X3 + 0.7X4 (X1, CEA grading, X3 = LN status by CT, X4 = T staging by CT, the critical value is 0.3) to estimate the possibility of LM, which has a better accuracy compared with CT.

Clinical significance of skip lymph node metastasis in gastric cancer patients

PURPOSE

Given the recent increase in the incidence of early gastric cancer, there is greater interest in identifying a minimally invasive therapy. The purpose of this study was to analyze the patterns of lymph node metastasis in patients with gastric cancer and to elucidate the clinical significance of skip metastasis.

METHODS

We retrospectively analyzed patterns of lymph node metastasis (LNM) and clinicopathologic factors related to skip metastasis.

RESULTS

Among 2963 patients with gastric cancer, 997 patients (33.6%) were detected as having LNM, and 27 patients (2.7%) with skip metastasis were detected among 997 patients with LNM. Skip metastasis were detected more frequently in the elderly. Compared with the N1 group, the skip metastasis group showed lower frequency of vascular invasion, and compared with the stepwise N2 group, the skip metastasis group showed smaller tumor size and a significantly higher incidence of negative lymphatic, vascular, and perineural invasion.

CONCLUSIONS

Currently there is no way to predict N2 station LNM including skip metastasis, D2 LN dissection for gastric cancer is thought to be the appropriate treatment, even during early stage disease. Minimally invasive therapy should be performed cautiously in consideration of possible skip metastasis.

Sentinel lymph node mapping in tumors of the pancreatic body: preliminary report

Aim of the study

Actual lymphatic drainage of pancreatic body neoplasms and the proper extent of lymphadenectomy remain unknown. The aim of the study was to define the exact lymphatic draining pattern using the dye mapping method.

Material and methods

The study enrolled patients who were operated on for tumor of the pancreatic body in the Department of General and Transplant Surgery of the Medical University of Lodz during 2010, with injection of 1 ml of blue dye (Patent Blue, Guerbet) in the centre of the neoplasm and sentinel node identification. Radical surgical management included distal pancreatectomy, whereas gastrojejunal or triple bypass anastomoses were performed in irresectable cases.

Results

The study group consisted of 13 patients with locally advanced tumors of the pancreatic body (T3 and T4, mean tumor size 4.9 cm). Lymphatic mapping was able to identify sentinel nodes in 5 of 13 cases (38.46%). A sentinel node was found in station 11p (3 cases) and 9 (1 case). Skip metastasis to the left gastric artery node (group 7) was noted. All identified sentinel nodes were metastatic; tumor deposits were confirmed in non-sentinel nodes as well.

Conclusions

In advanced pancreatic body tumors feasibility of sentinel node navigation is considerably restricted. Further studies in smaller tumors using optimized newer markers may define the exact lymphatic draining pattern.

Lymph node, peritoneal and bone marrow micrometastases in gastric cancer: Their clinical significance

The 7th TNM classification clearly states that micrometastases detected by morphological techniques (HE stain and immunohistochemistry) should always be reported and calculated in the staging of the disease (pN1mi or M1), while patients in whom micrometastases are detected by non-morphological techniques (e.g., flow cytometry, reverse-transcriptase polymerase chain reaction) should still be classified as N0 or M0. In gastric cancer patients, micrometastases have been detected in lymph nodes, the peritoneal cavity and bone marrow. However, the clinical implications and/or their prognostic significance are still a matter of debate. Current literature suggests that lymph node micrometastases should be encountered for the loco-regional staging of the disease, while skip lymph node micrometastases should also be encountered in the total number of infiltrated lymph nodes. Peritoneal fluid cytology examination should be obligatorily performed in pT3 or pT4 tumors. A positive cytology classifies gastric cancer patients as stage IV. Although a curative resection is not precluded, these patients face an overall dismal prognosis. Whether patients with a positive cytology should be treated similarly to patients with macroscopic peritoneal recurrence should be evaluated further. Gastric cancer cells are detected with high incidence in the bone marrow. However, the published results make comparison of data between groups almost impossible due to severe methodological problems. If these methodological problems are overcome in the future, specific target therapies may be designed for specific groups of patients.

A novel insight of sentinel lymph node concept based on 1-3 positive nodes in patients with pT1-2 gastric cancer

Background

Sentinel node (SN) biopsy has been practiced in gastric cancer in recent years, and many studies focused on the distribution of solitary lymph node metastasis (SLM) to assess the pattern of SN. In fact, there is usually more than one SN existing in gastric cancer. The distribution of SNs needs to be further re-evaluated.

Methods

A total of 289 patients in pT1-2 stage with 1-3 positive nodes confined to same compartment were included in this study with informed consents. The primary lesion was solitary (≤ 5.0 cm in diameter) and D2 or D3 lymph node dissection had been performed. The location of metastatic lymph nodes was analyzed retrospectively.

Results

Most positive nodes occurred in N1 compartment, with frequency of 79.6% to 85.7% based on site of tumor. In the lower third of stomach, no. 6 was the most common metastatic site and no. 3 was the second; the order was reversed for SLM. With increasing depth of tumor invasion, a progressively augmented nodal involvement was shown. Nearly a half appeared transverse metastasis when the tumor located at the lesser or greater curvature. Among skip metastasis, no. 7, 8a, 9 and 11p were the most common metastatic sites and the prognosis was as similar as that of patients with N1 involved only.

Conclusions

The 1-3 positive nodes in the same compartment should be possible SNs, and most of which are restricted in N1 in pT1-2 gastric cancer. Transversal and 2 stations lymph node metastasis are common.

Metastatic lymph node targeted chemosensitivity test for gastric cancer

BACKGROUND

The objective of this study was to compare the chemosensitivity of primary tumor and metastasized lymph node from patient with gastric adenocarcinoma.

MATERIALS AND METHODS

We studied 26 gastric cancer patients with lymph node metastasis who underwent gastric resection at the Korea University Guro Hospital from Feb 2007 to July 2008. The chemosensitivity of primary tumor and metastatic lymph node were studied using an adenosine triphosphate-based chemotherapy response assay (ATP-CRA).

RESULTS

The concordance rate of the ATP-CRA test was 30.8% (8/26). The concordance rate between primary tumor and metastatic N2 group lymph node was only 9.1% (1/11). The metastatic tumor inhibition rates with 5-fluorouracil, cisplatin, doxorubicin, and oxaliplatin were higher than the inhibition rates for primary tumor. Tumor inhibition rates was significantly different between primary tumor and metastatic tumor after doxorubicin treatment (27.734±20.95 versus 38.403±26.87, P=0.021). We detected simple correlations of tumor inhibition rates between primary and metastatic tumors with cisplatin (r=0.661, P<0.001) and doxorubicin (r=0.475, P=0.031).

CONCLUSIONS

We observed differences between first choice chemotherapeutic agents based on ATPCRA tests of primary tumor and metastatic tumor in lymph node. Therefore, chemotherapeutic agents should be carefully selected for adjuvant chemotherapy using a chemosensitivity test.

Routine modified D2 lymphadenectomy performance in pT1-T2N0 gastric cancer

AIM: To evaluate routine modified D2 lymphadenectomy in gastric cancer, based on immunohistochemically detected skip micrometastases in level II lymph nodes.

METHODS: Among 95 gastric cancer patients who were routinely submitted to curative modified D2 lymphadenectomy, from January 2004 to December 2008, 32 were classified as pN0. All level I lymph nodes of these 32 patients were submitted to immunohistochemistry for micrometastases detection. Patients in whom micrometastases were detected in the level I lymph node stations (n = 4) were excluded from further analysis. The level II lymph nodes of the remaining 28 patients were studied immunohistochemically for micrometastases detection and constitute the material of the present study.

RESULTS: Skip micrometastases in the level II lymph nodes were detected in 14% (4 out of 28) of the patients. The incidence was further increased to 17% (4 out of 24) in the subgroup of T1-2 gastric cancer patients. All micrometastases were detected in the No. 7 lymph node station. Thus, the disease was upstaged from stage IA to IB in one patient and from stage IB to II in three patients.

CONCLUSION: In gastric cancer, true R0 resection may not be achieved without modified D2 lymphadenectomy. Until D2+/D3 lymphadenectomy becomes standard, modified D2 lymphadenectomy should be performed routinely.

Clinical significance of skip metastasis in patients with gastric cancer

BACKGROUND

Metastasis appearing to bypass or skip tiers of lymph nodes (LNs) has been referred to as skip metastasis. The clinical impact of skip metastasis in gastric cancer remains unclear.

METHODS

In patients with gastric cancer, the clinicopathological features and postoperative prognoses of 21 patients with skip metastasis were evaluated and compared with findings in patients with group 1 (N1) or group 2 (N2) LN metastasis.

RESULTS

Of the 21 patients with skip metastasis, 9 patients had metastasis in the LN along the common hepatic artery (No. 8a), 8 patients had metastasis in the LN along the left gastric artery (No. 7), 2 patients had metastasis in LNs No. 7 and No. 8a, 1 patient had metastasis in the LN at the splenic hilum (No. 10), and 1 patient had metastasis in LN No. 10 and the LN along the splenic artery (No. 11). The mean diameter of the tumors in the patients with skip metastasis was 5.7 +/- 2.4 cm, which was significantly smaller than those in the N1 patients (7.9 +/- 4.1 cm) and N2 patients (9.3 +/- 4.6 cm). The incidence of serosal invasion, lymphatic vessel invasion, and peritoneal metastasis was lower in patients with skip metastasis compared with N2 patients. The 5-year survival rates were 70.2%, 62.0%, and 31.2% in patients with skip metastasis, patients with metastasis in group 1 LNs, and those with metastasis in group 2 LNs, respectively. The prognosis of patients with metastasis in group 2 LNs was significantly worse than that of patients with either skip metastasis (P = 0.0029) or metastasis in group 1 LNs (P < 0.0001).

CONCLUSION

Our data indicate that both the clinicopathological characteristics and the prognoses of patients with skip metastasis were similar to those of patients with N1 LN metastasis, but these features were not similar to those in patients with N2 LN metastasis. The sites of skip metastasis presented in the current study may be the key for applying the concept of the sentinel node in gastric cancer.

Validity of modified gastrectomy combined with sentinel node navigation surgery for early gastric cancer

BACKGROUND

The present study examined the clinical validity of modified gastrectomy for early gastric cancer, in terms of the results of sentinel node navigation surgery (SNNS), using infrared ray electronic endoscopy (IREE) plus indocyanine green (ICG) staining.

METHODS

One-hundred and sixty-one patients with fT1N0 gastric cancer were enrolled in the study. ICG (0.5 ml, 5 mg/ml) was injected endoscopically into four quadrants of the submucosa surrounding the cancer. Twenty minutes after the injection, sentinel lymph nodes (SNs) stained with ICG were observed intraperitoneally around the serosa and surrounding fat tissue. IREE was used to illuminate regional lymph nodes from the serosal side.

RESULTS

Group 2 lymph nodes were judged as SNs in 52 patients (32%). The most common locations of the SNs were stations No. 7 in each of the upper-, middle-, and lower-thirds of the stomach. In two patients, lymph node metastasis was positive. One of these patients, with cancer in the middle one-third of the stomach, had SNs in stations No. 3, 4sb, 4d, 7, and No. 11p, and had metastatic lymph nodes in No. 3 and No. 7 (all SNs). The other patient, with cancer in the lower one-third of the stomach, had SNs in No. 1, 3, 4d, and 6, and had a metastatic lymph node in No. 4d (SN). Skip metastasis was not observed in this study, and metastatic lymph nodes were judged to have been dissected by the D1+a procedure.

CONCLUSION

For T1N0 gastric cancer, modified gastrectomy (D1+a dissection) combined with SNNS is suitable; however, for those whose Group 2 lymph nodes are judged to be SNs, additional dissection of lymphatic basins detected by SNNS should be performed to confirm the absence of lymph node metastasis.