|Year : 2015 | Volume
| Issue : 2 | Page : 99-102
Improving lymph node harvest in colorectal cancer by intra-arterial injection of methylene blue: a randomized trial
Ayman A Albatanony MD 1, Alaa A Alseesi1, Mohamad S Ammar1, Mohammad Shaaban2
1 Department of General Surgery, Faculty of Medicine, Menoufia University, Shibin Alkom, Egypt
2 Department of Pathology, Faculty of Medicine, Menoufia University, Shibin Alkom, Egypt
|Date of Submission||14-Jan-2015|
|Date of Acceptance||23-Jan-2015|
|Date of Web Publication||23-Apr-2015|
Ayman A Albatanony
Department of General Surgery, Faculty of Medicine, Menoufia University, Shibin Alkom 32111
Source of Support: None, Conflict of Interest: None
Prognosis in colorectal carcinoma is related to the state of lymph node involvement. Myriad studies demonstrate that both survival and prognosis are significantly influenced by the number of lymph nodes harvested, particularly in node-negative disease.
The aim of this study was to evaluate the usefulness of injecting methylene blue into the main artery/arteries of resected colorectal specimens in terms of the total number of lymph nodes identified.
Patients and methods
The study included 54 patients randomly divided into two groups: group 1 (26 patients), in which resected specimens of colorectal carcinoma were injected with methylene blue, and group 2, in which no injection was carried out.
The total number of lymph nodes per patient in group 1 was 19.5 (17-39) [median (range)] and that in group 2 was 16.5 (8-19). The difference was statistically highly significant (P < 0.001). We also noticed that the best improvement in lymph nodes harvest was among the very small and small lymph nodes.
Methylene blue injection into the main artery/arteries is an effective and simple method for improving the lymph node harvest in resected specimens of colorectal carcinoma.
Keywords: colorectal carcinoma, lymph nodes harvest, methylene blue injection
|How to cite this article:|
Albatanony AA, Alseesi AA, Ammar MS, Shaaban M. Improving lymph node harvest in colorectal cancer by intra-arterial injection of methylene blue: a randomized trial. Egypt J Surg 2015;34:99-102
|How to cite this URL:|
Albatanony AA, Alseesi AA, Ammar MS, Shaaban M. Improving lymph node harvest in colorectal cancer by intra-arterial injection of methylene blue: a randomized trial. Egypt J Surg [serial online] 2015 [cited 2019 Aug 23];34:99-102. Available from: http://www.ejs.eg.net/text.asp?2015/34/2/99/155719
| Introduction|| |
Prognosis in colorectal carcinoma is clearly related to the degree of tumor infiltration through the bowel wall and the presence or absence of lymph node involvement. These two factors are the basis of the staging systems established for this disease. Today, almost 80 years after Dukes published his pioneer classification, all attempts to improve his proposal are mostly based on refinements of these two data  .
Many authors have advocated that a minimum of 12 lymph nodes are required for accurate colorectal cancer staging ,, .
Most studies suggest that node positivity rates increase with increased nodal harvest ,,, .
In other words, the higher the number of lymph nodes we examine, the higher the number of positive lymph nodes we find  .
Myriad studies demonstrate that both survival and prognosis are significantly influenced by the number of lymph nodes harvested, particularly in node-negative disease ,, .
In addition, the current paradigm of neoadjuvant chemoradiation for the treatment of rectal cancer complicates this issue because radiation is known to result in a decrease in the number of assessable lymph nodes  .
Hence, the concept of improving lymph node identification to facilitate further pathological assessment was introduced.
Immunohistochemical staining and fat clearance methods using alcohol, acetone, and other substances seem to be efficient techniques for upgrading lymph node identification ,, .
However, these methods are time-consuming, need additional equipment and expertise, and entail the use of hazardous materials  .
Methylene blue injection is found to be superior to other dyes because of higher availability and affordability , .
This method was originally introduced by Mδrkl et al.  . They injected the superior rectal artery with methylene blue solution to improve lymph node harvest in rectal carcinoma  .
In this study we carried the technique one step ahead by injecting methylene blue into the inferior mesenteric artery, right colic artery, and middle colic and/or left colic artery in colorectal carcinoma cases, rather than in rectal carcinoma cases only.
| Patients and methods|| |
This study was carried out between August 2011 and August 2014 in Menoufia University Hospital (Shibin Alkom, Egypt). The study included 54 consecutive patients who had undergone surgeries for colorectal carcinoma with a curative intent, both laparoscopic and open.
The patients were randomly divided into two groups: group 1, in which specimens were injected with methylene blue, and group 2, in which no injection was carried out. In group one, at the end of surgery and after removal of the specimen, the surgeon cannulated the main artery (arteries) with a 20-G plastic cannula and injected 15 ml of methylene blue dye (Merck, Darmstadt, Germany) (50 mg methylene blue in 5 ml distilled water, diluted in 10 ml 0.9% NaCl solution). The artery was then ligated and the specimen sent for histopathological evaluation following standard techniques (i.e. no special handling was done by the pathologist). Group 2 represented the control group, in which patients were operated upon by the same surgeons and the specimens were processed in the same way as group 1 and examined by the same pathologist.
Both groups were compared for age, sex, weight, total number of lymph nodes recovered, number of lymph nodes with malignant deposits, and the size of lymph nodes (≤1 mm, between 1 and 5 mm, and >5 mm). We recorded whether the patients received radiotherapy, the type and length of each specimen, and the TNM stage of each tumor.
Results were statistically analyzed using statistical package SPSS (version 16; SPSS Inc., Chicago, Illinois, USA). Student's t-test and the Mann-Whitney test were used for quantitative variables. The χ2 and Z tests were used for qualitative variables. P values less than 0.05 were considered significant.
| Results|| |
Twenty-six patients were assigned to group 1 (injection group) and 28 patients to group 2 (no injection group). [Table 1] shows a summary of the findings from both groups. Both groups were homogenous with regard to age, grade, sex, length, prior chemoradiotherapy, and type of resection. None of our cases had undergone a total colectomy. In group 1, we encountered no case with a lymph node count less than 12; however, in group 2 all three cases who had received prior radiotherapy had a lymph node count of less than 12.
| Discussion|| |
Insufficient lymph node harvest is commonly attributed to an incomplete resection by the surgeon. Moreover, it is an indication for expensive chemotherapy with known side effects  .
It is demonstrated that the total number of resected lymph nodes in colorectal cancer surgeries is an independent prognostic factor, as it is used as an indicator of the quality of surgery itself  .
It is understood that the accuracy of lymph node status assessment increases with an increase in the number of lymph nodes examined ,, , and most studies suggest that node positivity rates increase with increased nodal harvest  .
Methylene blue (methylthioninium chloride) when injected intra-arterially stains the arteries and capillaries, and, because the lymph nodes harbor a higher content of vessels in relation to the surrounding fat, they stain deeper than the surrounding fat and become easily identified  .
It is not entirely clear how the solution passes into the lymph nodes when injected into the specimens, but the most likely mechanism could be the increase in interstitial pressure caused by the injection and therefore induced lymphatic flow  . That is why we injected the specimens with methylene blue just after ligation of the pedicle(s) of the specimen.
Methylene blue solution is often found to be superior to other dyes because of its relative safety, higher availability, and affordability  .
In our study, the total number of lymph nodes recovered per patient was significantly higher in the methylene blue group compared with the control group (P < 0.001) ([Table 1]). Both groups were homogenous regarding other factors that could have affected the lymph node harvest (e.g. grade, length of specimen, age, prior chemoradiotherapy, type of resection) ([Table 1]).
The American Society of Anesthesiologists stated that grade, older age of the patient, and neoadjuvant radiotherapy are commonly found to be the main factors associated with a low lymph node harvest. Moreover, transverse colectomy and abdominoperineal resection are the methods of surgery associated with the poorest lymph node harvest in the histopathological examination of the surgical specimens  . Patients with higher BMI usually have a bigger mesocolon with a larger number of lymph nodes.
We noticed significant improvement in the identification of smaller lymph nodes: that is, less than 1 mm and between 1 and 5 mm [Table 1]. This is in accordance with other studies  .
This could be explained by the improved visual identification of smaller lymph nodes when using methylene blue because smaller lymph nodes are more likely to be mistaken for fat lobules if not stained. Overlooking small-sized lymph nodes is dangerous as lymph node size is not a reliable marker for lymph node metastases  ; that is, very small and small lymph nodes may contain metastases and large lymph nodes may be free and the enlarged size may be due to an immune response rather than due to metastases. Large lymph nodes in stage I/II disease might indicate a favorable outcome  .
Better identification of smaller lymph nodes is a good point in favor of the use of methylene blue.
Upstaging of colorectal cancer with improved nodal harvest is a controversial issue. Some authors claim that collecting and examining more lymph nodes will lead to upstaging of cases because of better identification of metastases that would otherwise be missed  . Others deny this  .
Extensive studies were carried out on the lymph node ratio ,, (i.e. the ratio between the number of positive lymph nodes resected and the total number of lymph nodes harvested) being a better prognostic factor than the mere presence of positive lymph nodes.
In our study, we noticed that the total number of lymph nodes harvested increased significantly with the use of methylene blue; yet simultaneously the number of positive lymph nodes per patient also increased from four to six. Thus, the lymph node ratio did not differ significantly (P > 0.05) ([Table 1]). Also, the treatment plans in three of our patients were changed with the finding of additional lymph nodes.
Preoperative use of chemoradiotherapy is known to reduce the number of lymph nodes identified in the specimens , . In a recent study, complete absence of recovered lymph nodes in resected specimens after neoadjuvant chemoradiation was observed in 7.6% of specimens  . Thus, the use of methylene blue in such cases is more clearly indicated  .
We also noticed significant improvement in the number of lymph nodes with deposits identified in the methylene blue group compared with the control group ([Table 1]). This can be attributed to the larger number of lymph nodes examined, but further study may be needed to evaluate the hypothesis that blue staining of lymph nodes makes the identification of micrometastases easier. Recently, Markl et al.  studied this hypothesis and concluded that identification of lymph node metastases was not improved using methylene blue.
| Conclusion|| |
We recommend the routine use of methylene blue intra-arterial injection in colorectal cancer, especially in patients treated with neoadjuvant therapy.
| Acknowledgements|| |
Conflicts of interest
| References|| |
Dedavid e Silva TL, Damin DC. Lymph node ratio predicts tumor recurrence in stage III colon cancer. Rev Col Bras Cir 2013; 40:463-70.
Porter GA, Urquhart R, Bu J, Johnson P, Rayson D, Grunfeld E. Improving nodal harvest in colorectal cancer: so what? Ann Surg Oncol 2012; 19:1066-73.
Goldstein NS. Lymph node recoveries from 2427 pT3 colorectal resection specimens spanning 45 years: recommendations for a minimum number of recovered lymph nodes based on predictive probabilities. Am J Surg Pathol 2002; 26:179-89.
Wong JH, Severino R, Honnebier MB, Tom P, Namiki TS. Number of nodes examined and staging accuracy in colorectal carcinoma. J Clin Oncol 1999; 17:2896-900.
Johnson PM, Malatjalian D, Porter GA. Adequacy of nodal harvest in colorectal cancer: a consecutive cohort study, J Gastrointest Surg 2002; 6:883-88 discussion 889-890.
Pheby DF, Levine DF, Pitcher RW, Shepherd NA. Lymph node harvests directly influence the staging of colorectal cancer: evidence from a regional audit. J Clin Pathol 2004; 57:43-7.
Ratto C, Sofo L, Ippoliti M, Merico M, Bossola M, Vecchio FM, et al
. Accurate lymph-node detection in colorectal specimens resected for cancer is of prognostic significance. Dis Colon Rectum 1999; 42:143-54 discussion 154-158.
Baxter NN, Virnig DJ, Rothenberger DA, Morris AM, Jessurun J, Virnig BA. Lymph node evaluation in colorectal cancer patients: a population-based study. J Natl Cancer Inst 2005; 97:219-25.
Le Voyer TE, Sigurdson ER, Hanlon AL, Mayer RJ, Macdonald JS, Catalano PJ, Haller DG. Colon cancer survival is associated with increasing number of lymph nodes analyzed: a secondary survey of intergroup trial INT-0089. J Clin Oncol 2003; 21:2912-9.
Chang GJ, Rodriguez-Bigas MA, Skibber JM, Moyer VA. Lymph node evaluation and survival after curative resection of colon cancer: systematic review. J Natl Cancer Inst 2007; 99:433-41.
Tsai HL, Lu CY, Hsieh JS, Wu DC, Jan CM, Chai CY, et al
. The prognostic significance of total lymph node harvest in patients with T2-4N0M0 colorectal cancer. J Gastrointest Surg 2007; 11:660-5.
Wong JH, Bowles BJ, Bueno R, Shimizu D. Impact of the number of negative nodes on disease-free survival in colorectal cancer patients. Dis Colon Rectum 2002; 45:1341-8.
Baxter NN, Morris AM, Rothenberger DA, Tepper JE. Impact of preoperative radiation for rectal cancer on subsequent lymph node evaluation: a population-based analysis. Int J Radiat Oncol Biol Phys 2005; 61:426-31.
Horne J, Bateman AC, Carr NJ, Ryder I. Lymph node revealing solutions in colorectal cancer: should they be used routinely? J Clin Pathol 2014; 67:383-8.
Parkash V, Bifulco C, Feinn R, Concato J, Jain D. To count and how to count, that is the question. Am J Clin Pathol 2010; 134:42-44.
Vogel C, Kirtil T, Oellig F, Stolte M. Lymph node preparation in resected colorectal carcinoma specimens employing the acetone clearing method. Pathol Res Pract 2008; 204:11-5.
Piñero A, Illana J, García-Palenciano C, Cañizarese F, Canteras M, Cañadillas V, et al
. Effect on oximetry of dyes used for sentinel lymph node biopsy. Arch Surg 2004; 139:1204-7.
Abbassi-Ghadi N, Boshier PR, Goldin R, Hanna GB. Techniques to increase lymph node harvest from gastrointestinal cancer specimens: a systematic review and meta-analysis. Histopathology 2012; 61:531-542.
Märkl B, Kerwel TG, Wagner T, Anthuber M, Arnholdt HM. Methylene blue injection into the rectal artery as a simple method to improve lymph node harvest in rectal cancer. Mod Pathol 2007; 20:797-801.
Markl B, Schaller T, Krammer I, Cacchi C, Arnholdt HM, Schenkirsch G, et al.
Methylene blue-assisted lymph node dissection technique is not associated with an increased detection of lymph node metastases in colorectal cancer. Mod Pathol 2013; 26:1246-1254.
Cianchi F, Palomba A, Boddi V, Messerini L, Pucciani F, Perigli G, et al
. Lymph node recovery from colorectal tumor specimens: recommendation for a minimum number of lymph nodes to be examined. World J Surg 2002; 26:384-9.
Swanson RS, Compton CC, Stewart AK, Bland KI. The prognosis of T3N0 colon cancer is dependent on the number of lymph nodes examined. Ann Surg Oncol 2003; 10:65-71.
Klepsyt E, Samalavicius E. Injection of methylene blue solution into the inferior mesenteric artery of resected rectal specimens for rectal cancer as a method for increasing the lymph node harvest. Tech Coloproctol 2012; 16:207-211.
Märkl B, Wünsch K, Hebick KU, Anthuber M, Probst A, Arnholdt HM, Spatz H. Methylene blue-assisted lymph node dissection in combination with ex vivo
sentinel lymph node mapping in gastric cancer. Histopathology 2009; 54:433-41.
Borowski DW, Banky B, Banerjee AK, Agarwal AK, Tabaqchali MA, Garg DK, et al.
Intra-arterial methylene blue injection into ex vivo
colorectal cancer specimens improves lymph node staging accuracy: a randomized controlled trial. Colorectal Dis 2014; 16:681-9.
Tekkis PP, Smith JJ, Heriot AG, Darzi AW, Thompson MR, Stamatakis JD. Association of Coloproctology of Great Britain and Ireland A national study on lymph node retrieval in resectional surgery for colorectal cancer. Dis Colon Rectum 2006; 49:1673-83.
Märkl B, Rößle J, Arnholdt HM, Schaller T, Krammer I, Cacchi C, et al
. The clinical significance of lymph node size in colon cancer. Mod Pathol 2012; 25:1413-22.
Jepsen RK, Ingeholm P, Lund EL. Upstaging of early colorectal cancers following improved lymph node yield after methylene blue injection. Histopathology 2012; 61:788-94.
Storli K, Sondenaa K, Furnes B, Leh S, Nesvik I, Bru T, et al.
Improved lymph node harvest from resected colon cancer specimens did not cause upstaging from TNM stage II to III. World J Surg 2011; 35:2796-2803.
Wang J, Hassett JM, Dayton MT, Kulaylat MN. Lymph node ratio: role in the staging of node-positive colon cancer. Ann Surg Oncol 2008; 15:1600-8.
Park IJ, Choi GS, Jun SH. Nodal stage of stage III colon cancer: the impact of metastatic lymph node ratio. J Surg Oncol 2009; 100:240-3.
Sjo OH, Merok MA, Svindland A, Nesbakken A. Prognostic impact of lymph node harvest and lymph node ratio in patients with colon cancer. Dis Colon Rectum 2012; 55:307-15.
Miller ED, Robb BW, Cummings OW, Johnstone PA. The effects of preoperative chemoradiotherapy on lymph node sampling in rectal cancer. Dis Colon Rectum 2012; 55:1002-7.
Le M, Nelson R, Lee W, Mailey B, Duldulao M, Chen YJ, et al
. Evaluation of lymphadenectomy in patients receiving neoadjuvant radiotherapy for rectal adenocarcinoma. Ann Surg Oncol 2012; 19:3713-8.
Lee WS, Lee SH, Baek JH, Lee WK, Lee JN, Kim NR, Park YH. What does absence of lymph node in resected specimen mean after neoadjuvant chemoradiation for rectal cancer. Radiat Oncol 2013; 8:202.
Markl B, Schaller T, Krammer I, Cacchi C, Spatz H. Optimal lymph node harvest in neoadjuvantly treated colorectal cancer using methylene blue assisted lymph node dissection technique. N A J Med Sci 2013; 6:51-56.