Preferential growth of bloodborne cancer cells in colonic anastomoses

Intraoperative esophageal washout reduces free intraluminal tumor cells during resection of carcinomas of the esophagus and cardia

OBJECTIVE

Intraluminally shed viable tumor cells might contribute to anastomotic recurrence in cancer of the esophagus and the cardia. The study aimed to establish a method of esophageal washout and, hence, to reduce intraluminal cancer cells before esophageal anastomosis.

METHODS

Forty-eight consecutive patients with esophago-gastric resection for histologically proven cancer of the esophagus or the cardia were included in a prospective, interventional study. Before transection, the esophagus was clamped proximally to the tumor and rinsed with 1:10 diluted povidone-iodine-solution (10 × 30 ml) applied by a transorally inserted 24F-Foley catheter. The first, fifth and tenth portion of the lavage fluid were sent to cytological examination.

RESULTS

Intraoperative frozen sections confirmed clear proximal resection margins of the esophagus. The cytological examination of the fluid recovered from the esophageal washout revealed malignant cells in 13/48 patients (27%). The presence of malignant cells was significantly less likely in patients with neoadjuvant treatment than in patients without neoadjuvant treatment: 2/23 (9%) vs. 11/25 (44%) (p = 0.009). Repetitive washout reduced the probability of detectable malignant cells from 13 to 8 (62%) patients after 5, and further to 4 patients (30%) after 10 washout maneuvers.

CONCLUSIONS

Free malignant cells may be present in the esophageal lumen following intraoperative manipulation of cancers of the esophagus or cardia. Transoral washout of the esophagus is novel, feasible and enables reduction or even elimination of these tumor cells. The reliability of this procedure raises with increasing washout volume. Esophageal washout might be especially worthwhile in patients who do not receive neoadjuvant therapy.

A Case of Esophageal Squamous Cell Carcinoma Metastasized to the Colonic Anastomotic Site of Right Hemicolectomy

A 73-year-old woman with a history of right hemicolectomy for advanced ascending colon cancer 14 years earlier was referred to our facility for a 2-month history of solid food dysphagia. An esophagogastroduodenoscopy revealed a 7-cm fungating and ulcerated mass in the middle to lower esophagus. The biopsy from the esophageal mass showed a moderately to poorly differentiated squamous cell carcinoma. A colonoscopy showed an end-to-end ileocolonic anastomosis with a 7-mm ulceration in the transverse colon. The biopsy of the ulceration at the anastomotic site showed a moderately to poorly differentiated squamous cell carcinoma with a morphology similar to that of the esophageal mass, rendering the diagnosis of metastatic esophageal squamous cell carcinoma. Colonic metastasis from esophageal squamous cell carcinoma, especially at the anastomotic site, is extremely rare. Although surgical trauma may not have contributed to the anastomotic site metastasis, given the distant timeline, its role in the pathogenesis of metastasis cannot be completely ruled out.

Cutaneous Metastasis after Surgery, Injury, Lymphadenopathy, and Peritonitis: Possible Mechanisms

Cutaneous metastases from internal malignancies are uncommon. Umbilical metastasis, also known as Sister Joseph nodule (SJN), develops in patients with carcinomatous peritonitis or superficial lymphadenopathy, while non-SJN skin metastases develop after surgery, injury, and lymphadenopathy. In this review, the possible mechanisms of skin metastases are discussed. SJNs develop by the contiguous or lymphatic spread of tumor cells. After surgery and injury, tumor cells spread by direct implantation or hematogenous metastasis, and after lymphadenopathy, they spread by extranodal extension. The inflammatory response occurring during wound healing is exploited by tumor cells and facilitates tumor growth. Macrophages are crucial drivers of tumor-promoting inflammation, which is a source of survival, growth and angiogenic factors. Angiogenesis is promoted by the vascular endothelial growth factor (VEGF), which also mediates tumor-associated immunodeficiency. In the subcutaneous tissues that surround metastatic lymph nodes, adipocytes promote tumor growth. In the elderly, age-associated immunosuppression may facilitate hematogenous metastasis. Anti-VEGF therapy affects recurrence patterns but at the same time, may increase the risk of skin metastases. Immune suppression associated with inflammation may play a key role in skin metastasis development. Thus, immune therapies, including immune checkpoint inhibitors reactivating cytotoxic T-cell function and inhibiting tumor-associated macrophage function, appear promising.

Hepatectomy increases metastatic graft and growth in an immunocompetent murine model of peritoneal metastases

BACKGROUND

Curative surgery of synchronous peritoneal metastases (PM) and colorectal liver metastases (LM) has been recently investigated as feasible option. When synchronous peritoneal and liver resection is not achievable, the sequence of the surgery remains unknown. Our hypothesis was that liver resection (LR) promotes peritoneal growth resulting in a non-resectable PM. We sought to analyse the effects of major LR and liver regeneration after hepatectomy in a murine model of PM and the associated angiogenesis.

METHODS

Murine model of colorectal PM in Balb/C mice was developed by intraperitoneal injection of different CT-26 tumour cell concentrations. Five days after the injection, mice were randomized into three groups: 68% hepatectomy group, sham laparotomy and control group without surgery. On post-operative days 1, 5 and 20, PM was evaluated macroscopically, tumour growth and liver regeneration by immunohistochemistry, and angiogenesis by immunofluorescence. Circulating progenitor cells, plasmatic cytokines and digestive arterial blood flow velocity measurements were also analysed.

RESULTS

Reproducible murine model of limited colorectal PM was obtained. Surgery induced PM increases and promoted neo-angiogenesis. Major hepatectomy influence the tumour growth in the late phase after surgery, the extent of extra-peritoneal metastasis and the increase of Ki-67 expression in the remnant liver.

CONCLUSIONS

This animal model confirms the pro-tumoural and pro-angiogenic role of surgery, laparotomy and major LR, which promotes the increase of angiogenic factors and their participation in PM growth. These results suggest that peritoneal resection should be first step in the case of two-step liver and peritoneal surgery for patients with colorectal PM and LM.

Systemic inflammation increases cancer cell adhesion to hepatic sinusoids by neutrophil mediated mechanisms

Interactions between endothelial selectins and selectin ligands expressed on tumor cells have been implicated in the binding of circulating metastatic cancer cells to the vascular endothelium during extravasation. Moreover, there is mounting evidence that inflammatory environments can accelerate the progression of metastasis by neutrophil mediated mechanisms. In this study, a physiologically relevant in vivo model of early metastasis coupled with intravital microscopy was used to visualize the trafficking of tumor cells within the liver vasculature in real time. Using GFP-labeled Lewis lung carcinoma subline H-59 cells, we show here that disrupting the interactions between endothelial selectins and tumor cell selectin ligands diminished tumor cell recruitment to the liver. Furthermore, systemic inflammation induced by intravenous injection of lipopolysaccharide significantly enhanced the metastatic potential of these lung carcinoma cells by increasing their propensity to adhere to the liver sinusoidal endothelium. Confocal microscopy revealed frequent colocalization of cancer cells with neutrophils and neutrophil depletion in vivo significantly attenuated the lipopolysaccharide-induced increase in H-59 cell adhesion. Although direct selectin-selectin ligand interactions contributed significantly to tumor cell adhesion to sinusoidal endothelial cells, we show here that in addition, interactions between adherent neutrophils within the inflamed sinusoids and circulating tumor cells may further increase tumor cell arrest in the liver.

Comparing and combining light dose fractionation and iron chelation to enhance experimental photodynamic therapy with aminolevulinic acid

BACKGROUND AND OBJECTIVES

Enhancement of photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) has been demonstrated experimentally using light dose fractionation or CP94 iron chelation. This study extends this research.

STUDY DESIGN/MATERIALS AND METHODS

In normal rat colon, CP94 administration and light dose fractionation were independently and concurrently employed to enhance ALA-PDT. In colonic rat tumors, the most successful enhancement regimes were employed separately.

RESULTS

Independent use of light dose fractionation and iron chelation produced similar results in normal colon (2.4- and 2.9-fold more necrosis than controls, respectively). Using both techniques simultaneously produced fivefold enhancement. In the colonic tumors, light dose fractionation and iron chelation (using different parameters) produced two and five times the volume of necrosis, respectively.

CONCLUSIONS

Both techniques significantly enhanced ALA-PDT in the normal and neoplastic tissues investigated and produced similar levels of enhancement when comparable parameters were employed. Concurrent use of light dose fractionation and iron chelation in normal colon produced considerably more enhancement than either technique could achieve independently.

Cancer surgery: risks and opportunities

In the recent past, several papers have pointed to the possibility that tumour removal generates a permissive environment in which tumour growth is potentiated. This phenomenon has been coined "perioperative tumour growth" and whilst it represents a departure in terms of our attitude to the surgical process, this concept was first hinted at by Paget(1) himself. Despite this, the time interval immediately before and after cancer surgery (i.e. the perioperative period) remains an underutilised interval during which chemotherapeutic regimens are rarely implemented. Herein, we present a summarised review of the literature that supports the concept that tumour removal may potentiate the growth of residual neoplastic disease. We also outline current knowledge regarding underlying mechanisms and in this manner highlight potential therapeutic entry points. Finally, we emphasise the urgent need for trials of agents that could protect patients against the harmful host-tumour interactions that may occur during the perioperative period.

Systemic effects of surgery: quantitative analysis of circulating basic fibroblast growth factor (bFGF), Vascular endothelial growth factor (VEGF) and transforming growth factor beta (TGF-beta) in patients with breast cancer who underwent limited or extended surgery

BACKGROUND

To assess if feature, extent and duration of surgery could influence levels of systemic proangiogenic cytokines vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and transforming growth factor beta (TGF-beta).

PATIENTS AND METHODS

We collected blood samples from 82 consecutive breast cancer patients who underwent various types of surgery, classified according to the magnitude of tissue injury in: minimal (quadrantectomy), moderate (mastectomy without reconstruction), and heavy [mastectomy followed by reconstruction with transversus recto-abdominal muscle cutaneous flap (TRAM)]. Samples were collected one day before surgery (D(-1)), at the end of surgical tumor removal (D0), and on 1st (D(+1)), 2nd (D(+2)) and 5th (D(+5)) day after surgery. Serum VEGF, bFGF and TGF-beta levels were measured by the enzyme immunoassay method.

RESULTS

On average a continuous decrease was observed for all growth factors from the day before operation to the 5th day after operation. On day (D(+5)) an increase was observed for patients who underwent extended respect to moderate surgery. These differences were found statistically significant for bFGF and VEGF (p = 0.05 and p = 0.025 respectively). A statistically different trend for type of operation was observed also for TGF-beta at 24-48 h: a minor reduction, compared to time of operation, was observed for minimal surgery, an intermediate reduction for moderate surgery and a higher decrease for extended surgery.

CONCLUSIONS

Angiogenic cytokines perioperative levels could be increased on 5th day (D(+5)) by extent of surgery and should induce perioperative stimulation of residual cancer cells. A better understanding of the time interval during which the sequelae of events in wound healing occur may be the basis for defining new therapeutic strategies that can interfere with tumor outgrowth sparing wound healing processes.

Excisional surgery for cancer cure: therapy at a cost

Excisional surgery is one of the primary treatment modalities for cancer. Minimal residual disease (MRD) is the occult neoplastic disease that remains in situ after curative surgery. There is increasing evidence that tumour removal alters the growth of MRD, leading to perioperative tumour growth. Because neoplasia is a systemic disease, this phenomenon may be relevant to all patients undergoing surgery for cancer. In this review we discuss the published work that addresses the effects of tumour removal on subsequent tumour growth and the mechanisms by which tumour excision may alter residual tumour growth. In addition, we describe therapeutic approaches that may protect patients against any oncologically adverse effects of tumour removal. On the basis of the evidence presented, we propose a novel therapeutic paradigm; that the postoperative period represents a window of opportunity during which the patient may be further protected against the oncological effects of tumour removal.

Surgery for colon and rectal cancer

Radical surgery remains the only potentially curative treatment for colorectal cancer. Major changes in the principles of rectal cancer resection have been recently described (total mesorectum excision) whereas there have been few changes in the principles of colonic cancer resection. This chapter presents surgical procedures for curative treatment of colorectal cancer in both the elective and emergency settings.

Rectal cancer recurrence: factors and mechanisms

OBJECTIVE

There have been significant developments in treatment for rectal carcinoma, both in surgical and adjuvant therapy. They may however have associated morbidity and hence individualized therapy for rectal cancer is desirable, to optimize treatment but avoid over-treatment for cases where the risk of recurrence is low.

MATERIALS AND METHODS

A literature review was undertaken of the reported incidence of recurrence of rectal carcinoma following curative surgery, factors which predispose to recurrence and proposed mechanisms for recurrence, and the evidence for each critically evaluated.

RESULTS

The incidence of local recurrence of rectal carcinoma following curative resection ranges from 2.6% to 32%, with an average of 15%. Tumour stage is the strongest predictor of tumour recurrence. Upstaging using molecular biology may predict increased risk of recurrence but is not yet proven. Histological factors including differentiation and vascular invasion increase recurrence but are imprecise. Tumour microvascular density and vascular endothelial growth factor (VEGF) levels may be predictive but need refinement. Adequate resection margins are important but recurrence may occur despite this. Tumour cell spillage and distant dissemination may be a mechanism for tumour recurrence following curative resection, but further research is required before this could be applied clinically.

CONCLUSION

Recurrence of rectal cancer remains a significant problem following 'curative' surgery. Multiple factors may influence recurrence risk, though currently however only tumour stage and histological resection margins have demonstrated sufficient importance for management decisions to be made upon them.

Targeting the epidermal growth factor receptor for therapy of carcinomas

As a group, the carcinomas represent a substantial proportion of all human malignancies, but, with relatively few exceptions, current treatments are ineffective. Modification of existing chemotherapeutic agents has not led to significant improvements in the survival of carcinoma patients, and development of new therapeutic strategies is imperative. It is now becoming apparent that activation of the epidermal growth factor receptor (EGF-R) has much wider implications than a straightforward stimulation of cell division. The pleiotropic effects of EGF-R signalling may influence tumour behaviour and the response of carcinomas to treatment; these are important considerations for the development of new therapies that aim to exploit the expression or modulate the function of the EGF-R in these tumours.

Role of cytokines and growth factors in promoting the local recurrence of breast cancer

The pathogenesis of local recurrence in breast cancer is not well understood. Breast-conserving surgery is particularly prone to local recurrence as it leaves behind breast tissue that may harbour occult cancer, and lends itself to enhanced intraoperative shedding of cancer cells due to narrower resection margins and transection of lymphatic channels. A review of clinical breast cancer studies as well as experimental research strongly suggests that these persisting cancerous cells are unlikely to develop into clinically evident disease if their environment remains unstimulated. However, an inordinately high local recurrence rate occurs at the surgical scar, and such recurrence must be triggered by the release of growth factors and cytokines into the healing wound. These factors can stimulate any available cancer cells which express the proper growth factor receptors. Perioperative strategies to neutralize this tumour cell-growth factor interaction should maximize local control.

Contribution of host-derived growth factors to in vivo growth of a transplantable murine mammary carcinoma

The contribution of host-derived growth factors to tumour growth in vivo was studied using the transplantable murine mammary carcinoma, MT1, grown in syngeneic mice. Promotion of growth of the mammary carcinoma by a factor(s) from the host was evident in experiments in which the carcinoma cells were inoculated intraperitoneally. In this environment, tumours develop as multiple solid nodules, each probably arising from an individual cell or a small cluster of cells. Tumour growth was found to occur in the peritoneal cavity following inoculation of 10(3) cells, but an inoculum of as few as ten cells grew if a leucocyte-rich exudate had first been induced. To determine which host-derived growth factors might contribute to growth of MT1, extracts of the tumour were first examined for growth factor activity. Fractionation of tumour extracts by either ion-exchange chromatography or gel filtration revealed several peaks of mitogenic activity, but none of this could be attributed to epidermal growth factor (EGF). Accordingly, an anti-EGF antibody was tested as a putative inhibitor of tumour growth as any effect of this antibody could be ascribed to removal of EGF derived from the host. The antibody was found to have potent anti-tumour activity when tested against MT1 tumours that had been inoculated into the peritoneal cavity. In contrast, the antibody had little effect on growth of the discrete tumour mass which formed when MT1 was transplanted subcutaneously. The results suggest that host-derived EGF contributes to establishment of microcolonies of MT1 carcinoma within the peritoneal cavity. This may be directly, by providing growth factors to supplement those produced by the tumour until it reaches a certain critical mass to sustain autocrine growth, or indirectly, by affecting the production of other growth-stimulatory factors or cytokines.

Effect of fibrin sealant on perianastomotic tumor growth in an experimental model of colorectal cancer surgery

Viable intraluminal tumor cells can penetrate a clinically intact rodent colonic anastomosis and give rise to perianastomotic tumor growth. The aim of this study was to determine whether transanastomotic cell migration can be prevented by fibrin-based tissue sealant. Following distal colonic transection and reanastomosis with 5/0 silk sutures, Fischer F344 rats were randomly allocated to three experimental groups. In Group A, a circumferential ring of tissue sealant was placed around the serosal surface of the anastomosis; in Group B, sealant was limited to 50 percent of the anastomotic circumference; and, in Group C, no sealant was applied. All rats then had 10(5) Mtln3 carcinoma cells injected into the proximal colonic lumen via a rectal catheter. The incidence of perianastomotic tumor at 21 days was significantly lower in Group A (3 of 14 animals) than in Group B (11 of 16 rats) (P = 0.012; Fisher's exact test) or Group C (10 of 14 rats; P = 0.011). A further experiment demonstrated that sealant did not protect the anastomosis when tumor cells were instilled directly into the peritoneal cavity. A topical carcinocidal action therefore appears unlikely, but our results suggest that a circumferential anastomotic ring of fibrin sealant forms an effective mechanical barrier preventing intraluminal tumor cells from reaching the peritoneal cavity.

Effect of suture material on tumour cell adherence at sites of colonic injury

In an experimental animal model, radiolabelled viable intraperitoneal adenocarcinoma cells adhered in similar numbers to normal rat colon and that injured by a 1-cm colotomy, with median cell counts of 7002 and 8602 respectively (P not significant). Repair of the colotomy with interrupted silk resulted in a significant increase in the median number of cells adhering to the injury site (21,888; P = 0.0001 versus normal colon). Repair with Prolene had no effect on tumour cell adherence (a median of 7449 cells adhered; P not significant versus normal colon). Tumour cell adherence at sites of colonic injury is dependent on the suture material used and not on the injury itself in this model. This may be important when choosing suture type for anastomosis in patients undergoing surgery for colorectal cancer.

Tissue procoagulant activity may be important in sustaining metastatic tumour growth

There is strong evidence for an association between the haemostatic system and malignancy. Thus, cancer may adversely affect the host coagulation system while the haemostatic system may play a role in the development of both primary and metastatic tumours. Metastatic growth is not dependent simply on haemodynamic factors, and properties of both the tumour cell and host organ are important determinants of the site of metastatic growth. Previous studies have demonstrated that some organs are preferred sites for metastasis while others are less preferred or resistant. We have measured the procoagulant activity (PCA) of normal rat and human tissues and correlated the results with the previously reported ability of these organs to support metastatic tumour growth. In addition, we determined changes in PCA in rat tissues during oral anticoagulant therapy, and following colonic anastomosis and partial hepatectomy, procedures which are known to affect experimental metastasis. In both rat and human studies, organs which are preferred sites for metastasis had significantly higher PCA than non-preferred organs (P less than 0.001). The PCA of adrenal, lung and colon was significantly reduced by administration of warfarin (P less than 0.001). PCA was significantly (P less than 0.001) increased in both colonic anastomoses and regenerating liver and followed a time course similar to that of the enhanced tumour growth usually seen in these situations. Although the exact source of the procoagulant activity remains to be determined, the results suggest that there is a broad correlation between tissue PCA and the ability of a tissue to support metastatic tumour growth.

Enhanced growth of tumour cells in healing colonic anastomoses and laparotomy wounds

In the past, it has been noted that experimental tumour cells inoculated into the peritoneal cavity or into the lumen of the bowel will grow at a recently formed colonic anastomosis. However, it has previously been unclear whether the healing process enhances tumour growth or whether the presence of a suture line merely allows the tumour cells to gain access to the tissues. In the present study, using the hooded Lister rat, we have confirmed these findings by showing that growth of the syngeneic MC28 sarcoma and OES5 breast carcinoma occurs preferentially at colonic anastomoses and laparotomy wounds after intraperitoneal injection, and at colonic anastomoses after intraluminal injection. In previous studies using the MC28 sarcoma and the OES5 breast carcinoma injected by the intracardiac route (so that tumour cells reach normal and healing tissues in approximately equal numbers) we have shown that tumour growth is enhanced in healing wounds but not in the surrounding normal tissues when cells reach a healing colonic anastomosis or laparotomy wound within 2 h of its formation. Furthermore, by studying the distribution of radiolabelled tumour cells after intracardiac injection, we have calculated that the probability of a tumour cell leading to a deposit in a healing anastomosis or laparotomy wound is increased 1,000 fold compared to normal tissue. No previous studies have combined the data for intracardiac, intraluminal and intraperitoneal injection of tumour cells using the same animal model. We conclude that the same phenomenon of tumour growth enhancement in colonic anastomoses and laparotomy wounds reported after intracardiac injection of tumour cells may well be enhancing tumour growth after intraperitoneal and intraluminal injection.(ABSTRACT TRUNCATED AT 250 WORDS)