Study on the relationship between lymphatic vessel density and distal intramural spread of rectal cancer

Rare Case of Cecal Signet Ring Cell Carcinoma with Distal Intramural Spread

In this paper, we report a rare case of cecal Signet ring cell carcinoma (SRCC) with Distal intramural spread (DIS) along with a review of the literature. A 71-year-old woman suffering from vomiting, abdominal pain, and abdominal distension was admitted to a hospital and was suspected to have ileus. She was transferred to our hospital and diagnosed with cecal cancer with intestinal obstruction. Laparotomy was performed, after which she was diagnosed with cecal SRCC by histopathological examination. A submucosal lesion was located 55 mm from the distal side of the main tumor. This lesion was also diagnosed as SRCC. It was not exposed to the epithelium or the serous membrane. The submucosal tumor was diagnosed as DIS of cecal SRCC. After the operation, she underwent chemotherapy with FOLFIRI+Cet (5-fluorouracil, leucovorin, and irinotecan plus cetuximab). At a follow-up examination nine months after surgery, she was found to be doing well.

Tumor lymphangiogenesis and new drug development

Traditionally, tumor-associated lymphatic vessels have been regarded as passive by-standers, serving simply as a drainage system for interstitial fluid generated within the tumor. However, with growing evidence that tumors actively induce lymphangiogenesis, and that the number of lymphatic vessels closely correlates with metastasis and clinical outcome in various types of cancer, this picture has changed dramatically in recent years. Tumor-associated lymphatic vessels have now emerged as a valid therapeutic target to control metastatic disease, and the first specific anti-lymphangiogenic drugs have recently entered clinical testing. Furthermore, we are just beginning to understand the whole functional spectrum of tumor-associated lymphatic vessels, which not only concerns transport of fluid and metastatic cells, but also includes the regulation of cancer stemness and specific inhibition of immune responses, opening new venues for therapeutic applications. Therefore, we predict that specific targeting of lymphatic vessels and their function will become an important tool for future cancer treatment.

Broad targeting of angiogenesis for cancer prevention and therapy

Deregulation of angiogenesis – the growth of new blood vessels from an existing vasculature – is a main driving force in many severe human diseases including cancer. As such, tumor angiogenesis is important for delivering oxygen and nutrients to growing tumors, and therefore considered an essential pathologic feature of cancer, while also playing a key role in enabling other aspects of tumor pathology such as metabolic deregulation and tumor dissemination/metastasis. Recently, inhibition of tumor angiogenesis has become a clinical anti-cancer strategy in line with chemotherapy, radiotherapy and surgery, which underscore the critical importance of the angiogenic switch during early tumor development. Unfortunately the clinically approved anti-angiogenic drugs in use today are only effective in a subset of the patients, and many who initially respond develop resistance over time. Also, some of the anti-angiogenic drugs are toxic and it would be of great importance to identify alternative compounds, which could overcome these drawbacks and limitations of the currently available therapy. Finding “the most important target” may, however, prove a very challenging approach as the tumor environment is highly diverse, consisting of many different cell types, all of which may contribute to tumor angiogenesis. Furthermore, the tumor cells themselves are genetically unstable, leading to a progressive increase in the number of different angiogenic factors produced as the cancer progresses to advanced stages. As an alternative approach to targeted therapy, options to broadly interfere with angiogenic signals by a mixture of non-toxic natural compound with pleiotropic actions were viewed by this team as an opportunity to develop a complementary anti-angiogenesis treatment option. As a part of the “Halifax Project” within the “Getting to know cancer” framework, we have here, based on a thorough review of the literature, identified 10 important aspects of tumor angiogenesis and the pathological tumor vasculature which would be well suited as targets for anti-angiogenic therapy: (1) endothelial cell migration/tip cell formation, (2) structural abnormalities of tumor vessels, (3) hypoxia, (4) lymphangiogenesis, (5) elevated interstitial fluid pressure, (6) poor perfusion, (7) disrupted circadian rhythms, (8) tumor promoting inflammation, (9) tumor promoting fibroblasts and (10) tumor cell metabolism/acidosis. Following this analysis, we scrutinized the available literature on broadly acting anti-angiogenic natural products, with a focus on finding qualitative information on phytochemicals which could inhibit these targets and came up with 10 prototypical phytochemical compounds: (1) oleanolic acid, (2) tripterine, (3) silibinin, (4) curcumin, (5) epigallocatechin-gallate, (6) kaempferol, (7) melatonin, (8) enterolactone, (9) withaferin A and (10) resveratrol. We suggest that these plant-derived compounds could be combined to constitute a broader acting and more effective inhibitory cocktail at doses that would not be likely to cause excessive toxicity. All the targets and phytochemical approaches were further cross-validated against their effects on other essential tumorigenic pathways (based on the “hallmarks” of cancer) in order to discover possible synergies or potentially harmful interactions, and were found to generally also have positive involvement in/effects on these other aspects of tumor biology. The aim is that this discussion could lead to the selection of combinations of such anti-angiogenic compounds which could be used in potent anti-tumor cocktails, for enhanced therapeutic efficacy, reduced toxicity and circumvention of single-agent anti-angiogenic resistance, as well as for possible use in primary or secondary cancer prevention strategies.

Active lymphangiogenesis is a major risk factor for anastomotic leakage following sphincter-sparing resection of rectal cancer

OBJECTIVE

Anastomotic leakage is a major complication of rectal surgery and controversy about its risk factors still exists. The aim of present study was to identify risk factors for anastomotic leakage following sphincter-sparing resection of rectal cancer, focusing on the role of tissular lymphatic vessel density (LVD) in tumorous margin and distal clearance margin.

METHODS

In a 9-year period, from September 1999 to September 2009, 750 consecutive patients who underwent anterior resection with restoration of the bowel continuity were included. Univariate and multivariate analysis were applied to identify risk factors for anastomotic leakage.

RESULTS

The rate of anastomotic leakage was 7.6% (57 of 750 patients). In a multivariate analysis, high LVD in tumorous margin [P=0.0017; odds ratio (OR)=5.93; 95% confidence interval (CI)=2.61-8.514], high LVD in distal clearance margin (P=0.0011; OR=6.05; 95% CI=2.72-10.108) and lower tumor location (P=0.006; OR=4.620; 95% CI=1.76-6.97) were identified as independent factors for anastomotic leakage. A significant LVD correlation was shown by Spearman's rank test between the tumorous and distal clearance margin (r=0.796).

CONCLUSIONS

Tissular LVD in tumorous or distal clearance margin and lower tumor location are important risk factors for anastomotic leakage.

Patterns of local recurrence in rectal cancer; a study of the Dutch TME trial

AIM OF THE STUDY

In patients from the Dutch TME trial patterns of local recurrence (LR) in rectal cancer were studied. The purpose was to reconstruct the most likely mechanisms of LR and the effect of preoperative radiotherapy.

METHODS

1417 patients were analyzed; 713 were randomized into preoperative radiotherapy and total mesorectal excision (RT + TME), 704 into TME alone. Of the 114 patients with LR, the subsites of LR were determined and related to tumor and treatment factors.

RESULTS

Overall 5-year LR-rate was 4.6% in the RT + TME group and 11.0% in the TME group. Presacral local recurrences occurred most in both groups. Radiotherapy reduced anastomotic LR significantly, except when after low anterior resection (LAR) distal margins were less than 5 mm. Abdominoperineal resection (APR) mainly resulted in presacral LR. Even after resection with a negative circumferential resection margin, LR-rates were high. Thirty percent of the patients had advanced tumors, which resulted in 58% of all LRs. Lateral LR comprised 20% of all LR. Presacral and lateral LR resulted in a poor prognosis, in contrast to anterior or anastomotic LRs with a relatively good prognosis.

CONCLUSIONS

RT reduces LR in all subsites and is especially effective in preventing anastomotic LR after LAR. APR-surgery mainly results in presacral LR, which may be prevented by a wider resection. In the TME trial many advanced tumors were included, rather requiring chemoradiotherapy instead of RT. Currently, with good imaging techniques, better selection can take place. Especially lateral LR might be a problem in the future.

Lymphatic vessel density as predictive marker for the local recurrence of rectal cancer

PURPOSE

This study identified possible factors affecting the frequency of local recurrence of rectal cancer, focusing on lymphangiogenesis as a predictor.

METHODS

We examined 352 primary rectal cancer cases and 34 local recurrent specimens by lymphatic hyaluronan receptor. The lymphangiogenesis of all specimens was evaluated by measuring by lymphatic vessel density and other clinicopathologic factors.

RESULTS

A multivariate analysis using the Cox proportional hazard model showed that lymphatic vessel density, lymph node metastasis, depth of invasion, and lymphatic invasion were significant independent predictive factors of local recurrence; lymphatic vessel density was the strongest predictor. In addition, a significant correlation was found between the lymphatic vessel density of the primary rectal cancer and the corresponding local recurrent cases.

CONCLUSIONS

We suggest that rectal cancers, which have active lymphangiogenesis, also demonstrate a greater potential for local recurrence, and the lymphatic vessel density of surgical specimens is an independent risk factor and a valuable predictive factor for the local recurrence of rectal cancer.

Intratumoral lymphangiogenesis of esophageal squamous cell carcinoma and relationship with regulatory factors and prognosis

The clinical and pathological significance of intratumoral lymphangiogenesis (ITL) with human esophageal squamous cell carcinomas (ESCC) remains unclear, as does the role of signaling molecules such as vascular endothelial growth factor (VEGF)-A,C, platelet-derived growth factor (PDGF)-A, and p53, in the regulation of ITL. Lymphatic vessel density (LVD) was significantly increased in VEGF-A and VEGF-C immunohistochemical score 1 and 2-3 groups as compared to the score 0 group and also with high of VEGF-A, VEGF-C and PDGF-A mRNA expression. Both LVD and blood vessel density (BVD) were significantly greater in the p53 gene mutant group than in the wild-type group. Lymph node metastasis was significantly more frequent with than without ITL and Kaplan-Meier analysis indicated a significantly poorer prognosis. Multivariate analysis using Cox proportional hazard method showed that invasion depth, lymph node metastasis and ITL were independent prognostic factors.