Osteopontin Levels Are Persistently Elevated for 4 weeks Following Minimally Invasive Colorectal Cancer Resection.

INTRODUCTION: Osteopontin (OPN) is an integrin binding phosphorylated glycoprotein secreted by macrophages and leukocytes that is found in extracellular fluids and sites of inflammation; various forms of CD44 serve as receptors. Osteopontin, expressed by numerous cancers, enhances tumor progression and angiogenesis via the PI3K/AKT and ERK mediated pathways in concert with Vascular Endothelial Growth Factor (VEGF); OPN also plays a role in wound healing. The impact of minimally invasive colorectal resection (MICR) for colorectal cancer (CRC) on plasma OPN levels is unknown. This study's goal was to assess blood levels during the first month after MICR. METHOD: Patients undergoing MICR for CRC who were enrolled in an IRB approved tissue/prospective data bank for whom preoperative, postop Day (POD) 1, POD 3, and at least 1 late postop plasma sample (POD 7-34) were available were studied. Osteopontin levels were determined in duplicate via enzyme linked immunosorbent assay (ELISA) (results reported as mean ± SD). The Wilcoxon signed rank test was used for analysis (significance P < .05). RESULTS: A total of 101 CRC patients (63% colon and 37% rectal) met study criteria. The mean preop OPN level was 89.2 ± 36.8 (ng/ml) for the entire group. Significantly elevated (P < .001) mean plasma levels were detected, vs preop, on POD1 (198.0 ± 67.4; n = 101), POD 3 (186.0 ± 72.6, n = 101), POD 7-13 (154.1 ± 70.2, n = 70), POD14-20 (146.7 ± 53.4, n=32), and POD 21-27 (123.0 ± 56.9, n = 25). No difference was noted at the POD 27-34 timepoint (P > .05). CONCLUSION: Plasma OPN levels are significantly elevated over baseline for a month after MICR for CRC. The early rise in OPN levels may be related to the postop acute inflammatory response. The persistent elevation noted in weeks 2-4, however, may be a manifestation of wound healing in which OPN plays a role. Similar persistent plasma elevations of VEGF, angiopoietin 2 (ANG 2), and 11 other proangiogenic proteins have been noted and, collectively, may promote angiogenesis in residual tumors.

A colonoscopic overtube system that creates a 'therapeutic zone' and permits retraction facilitates endoscopic submucosal dissection, was associated with fewer deep bowel wall injuries and instrument exchanges, and required less lifting solution vs classic endoscopic submucosal dissection in an ex vivo bovine model.

INTRODUCTION: Endoscopic submucosal dissection (ESD) is the 'gold standard' for large flat polyps; nevertheless, the rate of adoption in the USA is low. In ESD, the polyp is 'surgically' detached with a needle knife after a submucosal lift; gravity and the dissection cap are used for retraction. ESD would be easier if active retraction were possible. In an ex vivo bovine colon model, this study assessed an overtube system (Boston Scientific ORISE Tissue Retraction System, TRS) that permits retraction and creates 'an operative field' for removal of rectal/sigmoid lesions. METHOD: Classic ESD (C-ESD) was compared to TRS-facilitated ESD (TRS-ESD). Cleaned/preserved bovine large bowel was used, and two 2-cm 'lesions'/colon were branded onto the mucosal surface 25 and 35 cm from the anus. Submucosal saline lifts were made using a thin catheter and a standard needle knife. We tracked case length, number of instrument exchanges (to refresh lift), the volume of lift solution, the fullness of resection, and deep muscle injuries. RESULTS: Fifty ESDs were carried out in 25 colons (25 C-ESD, 25 TRS-ESD). Complete resections were noted in all cases. The TRS method required fewer instrument exchanges (median 5) vs C-ESD (median 9, p < 0.0001) and less lift solution (median 39 ml) than the C-ESD cases (median 55 ml, p = 0.0003). TRS-ESD was associated with fewer deep muscle injuries (median 2) than C-ESD (median 3, p = 0.0191). Finally, the TRS group's median case length (34.5 min) was shorter than that of C-ESD (41 min, p = 0.0543). CONCLUSION: The TRS system provides retraction and facilitates ESD regarding the number of lift injections, the volume of lift solution needed, and avoidance of muscle injuries. Of note, there is an apparent TRS learning curve, and the device mandates a distal-to-proximal approach and initial 360 degree mucosal incision. Further study is warranted.

Sclerotherapy needle injections can expand the subserosal and muscularis propria layers and cause a stable mucosal lift in ESD/EMR patients.

BACKGROUND: A mucosal lift is needed for ESD and EMR. Most lifts are made via sclerotherapy needle injection. The firm push needed to penetrate the mucosa often leaves the needle tip in the deep wall. The needle is next withdrawn and fluid injected until a sharp lift (due to submucosal expansion) begins to form; the needle is then held steady and the injection finished. The initial injection may result in a subtle deep lift that resolves quickly. It was the authors' belief that only submucosal expansion could lead to a stable mucosal lift. A colonic ESD case in which a polyp was inadvertently resected via needle knife in an expanded subserosal plane led to a questioning of this position. This study's purpose was to determine if stable deep wall mucosal lifts can be generated via bowel wall injection. METHODS: Transmucosal and intramural injections into bovine large bowel were carried out. Stable lifts and lift cross sections were made and examined grossly and histologically to determine the location of the lift fluid. Clinical ESD videos were also reviewed. RESULTS: Over 200 intact and cross-sectioned lifts were assessed. Gross inspection revealed two types of lifts (superficial and deep), whereas cross sections and histologic analyses revealed examples of stable expansion of the submucosal, muscularis propria, and subserosal layers post injection. Clinical "deep" lifts were also found. Superficial lifts are more focal and taller, whereas deep wall lifts are broader and less prominent. CONCLUSION: Stable deep wall mucosal lifts occur and are likely due to the deep starting point of the needle post insertion. If ESD/EMR are attempted with a deep lift, the chances of failure or perforation are high. Lifts must be carefully scrutinized before starting ESD/EMR. Other means of lift establishment should be evaluated and considered.

Plasma levels of the proangiogenic protein CXCL16 remains elevated for 1 month after minimally invasive colorectal cancer resection.

BACKGROUND: Inflammation-induced endothelial precursor cell recruitment and angiogenesis are thought to be associated with CXCL16-CXCR6 pair activity. This study's main purpose was to determine plasma CXCL16 levels after minimally invasive colorectal resection (MICR) for colorectal cancer (CRC); an adjunct study assessed wound fluid (WF) and plasma CXCL16 levels in a separate group of CRC patients. METHODS: CRC patients who had MICR and for whom plasma was available in a tissue bank were eligible. Plasma samples were collected preoperatively from all patients. Samples were also collected on postoperative days (POD) 1 and 3 and at various late postoperative time points (POD 7-34). In a separate study, blood and intra-abdominal wound fluid (WF) samples were collected from CRC MICR patients (pts). Samples were stored at - 80 °C. CXCL16 levels were determined via ELISA. The Wilcoxon signed-rank and Mann and Whitney tests were used for analysis. RESULTS: Main study: 86 CRC pts. were included. The mean preoperative plasma CXCL16 level was 2.36 ± 0.57 ng/ml. Elevated mean plasma levels (p <  0.0001 × first 4 time points) were noted on POD 1 (2.82 ± 0.81, n = 86), POD 3 (3.12 ± 0.77, n = 82), POD 7-13 (3.28 ± 0.88, n = 64), POD 14-20 (3.03 ± 0.62, n = 24), POD 21-27 (3.06 ± 0.67, n = 20, p = 0.0003), and POD 28-34 (3.17 ± 0.43, n = 11, p = 0.001) vs. preop levels. WF study: In the adjunct study, plasma and WF CXCL16 levels were determined for 23 CRC MICR pts. WF levels at all time points were significantly elevated over plasma levels. CONCLUSION: Plasma CXCL16 levels were elevated for 4 weeks after minimally invasive colorectal resection for cancer. Also, WF CXCL16 levels were 3-10 times greater than the corresponding plasma concentrations. The source of the late plasma elevations may be the healing wound. Increased plasma CXCL16 levels may promote tumor angiogenesis in the first month after MICR.

Warm and Humidified Versus Cold and Dry CO2 Pneumoperitoneum in Minimally Invasive Colon Resection: A Randomized Controlled Trial.

INTRODUCTION: Peritoneal insufflation with warm-humidified (WH) CO2 gas during minimally invasive surgical procedures is purported to prevent hypothermia and peritoneal desiccation and is associated with decreased postoperative IL-6 levels. This randomized study's purpose was to determine the clinical impact of WH versus cold-dry (CD) CO2 in minimally invasive colon resection (MICR), and to assess perioperative plasma levels of IL-6, TIMP-1, sVEGF-R1, and HSP-70 after MICR. METHODS: Operative and short-term clinical data plus perioperative blood samples were collected on MICR patients randomized to receive either WH (36.7°C, 95% humidity) or CD (room temperature, 0% humidity) CO2 perioperatively. Peritoneal biopsies were taken at the start and end of surgery. Outcomes tracked included core temperature, postoperative in-hospital pain levels, analgesia requirements, and standard recovery parameters. Preoperative and postoperative days (PODs) 1 and 3 plasma protein levels were determined via ELISA. RESULTS: A total of 101 patients were randomized to WH CO2 (50) or CD CO2 (51). The WH group contained more diabetics ( P = .03). There were no differences in indication, minimally invasive surgical method used, or core temperature. Pain scores were similar; however, the WH patients required less narcotics on PODs 1 to 3 ( P < .05), and less ketorolac on PODs 1 and 2 ( P < .03). No differences in length of stay, complication rates, or time to flatus/diet tolerance were noted. Plasma levels of the 4 proteins were similar postoperatively. Though insignificant, the WH group had less marked histologic changes on "end-of-case" peritoneal biopsies. CONCLUSION: This study found significantly lower pain medication requirements for PODs 1 to 3 for the WH group; however, because there were no differences in the pains scores between the groups, firm conclusions regarding WH CO2 cannot be made.

Surgical Treatment of Diverticulitis: Hand-Assisted Laparoscopic Resection Is Predominantly Used for Complex Cases and Is Associated With Increased Postoperative Complications and Prolonged Hospitalization.

Introduction Laparoscopic (LAP) colectomy is now the "gold" standard for diverticulitis; the role of hand-assisted LAP (HAL) and Open methods today is unclear. This study assessed the elective use of these methods for diverticulitis. Methods A retrospective review of demographic, comorbidity (Carlson Comorbidity Index [CCI]), resection type, and short-term outcomes was carried out. Results There were 125 (44.5%) LAP, 125 (44.5%) HAL, and 31 (11%) Open cases (overall N = 281). The mean age, body mass index, and percentage of high-risk patients (CCI score >2) of the HAL group were greater (P < .05) than the LAP group (vs Open, P = ns). The Open group's mean age and percent with CCI >2 was greater when compared with the LAP group (P < .05). More Open (P < .05) and HAL patients had complex disease (Open, 63%; HAL, 40%, LAP, 22%) and were diverted (Open, 35%; HAL, 10%; LAP, 3%). Time to bowel movement was not different; however, there was a stepwise increase in median length of stay (LOS; days) from the LAP (5 days) to HAL (6 days) to Open group (7 days) (P < .05 for all). The LAP complication rate (22.4%) was lower (P < .05) than the HAL (42.4%) or Open groups' (45.2%) rates. The LAP surgical site infection rate (5.6%) was lower (P < .05) than the HAL (12.8%) or Open groups (19.6%). Conclusion The HAL and Open groups had more high risk, complex disease, diverted, and older patients than the LAP group; likewise, the overall complication rate and LOS was higher in the HAL and Open groups. Use of HAL methods likely contributed to the high minimally invasive surgery utilization rate (89%).

Efficacy of laparoscopic-assisted approach for reversal of Hartmann's procedure: results from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database.

INTRODUCTION: Morbidity after reversal of Hartmann's procedure remains high. The laparoscopic approach (LAP) may be associated with lower morbidity versus open Hartmann's closure. This study's aim is to compare results after LAP and OPEN colostomy takedown and Hartmann's reversal. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried from 2005 to 2012 for CPT procedure codes 44227 (LAP) and 44626 (OPEN). Exclusion criteria included: ventilator dependence, ASA class 4 or 5, SIRS, sepsis, emergency case, and advanced malignancy. Demographic parameters were assessed as well as comorbidities and short-term outcomes. Statistical methods used include Fisher's exact test for categorical variables and Student's t test for continuous variables. RESULTS: In total, 4,148 patients underwent stoma closure and Hartmann's reversal (LAP 732 [17.6 %], OPEN 3,416 [82.3 %]). The mean BMI was lower in the LAP (mean ± SD 27.6 ± 6.6) versus OPEN group (28.3 ± 6.8, p = 0.012). The groups were similar as regards comorbidities except for dyspnea (LAP 5.6 %, OPEN 7.8 %, p = 0.043). The mean surgery times were similar and the median LOS shorter in the LAP versus OPEN groups (5 vs 6 days, p < 0.0001). A lower overall morbidity rate was noted for the LAP group (18.4 % vs OPEN 27 %, p < 0.0001) but mortality was statistically similar. Lower rates were noted in the LAP group for the following complications: incisional SSI (10.4 vs 14.1 %, p = 0.033), organ space SSI (3.1 vs 5.0 %, p = 0.033), UTI (1.6 vs 3.3 %, p = 0.005), sepsis (3.4 vs 6.0 %, p = 0.038), and reoperation (3.1 vs 5.4 %, p = 0.011). CONCLUSION: Only 18 % of Hartmann's reversal's were done using LAP methods. The LAP and OPEN groups were similar except for gender, BMI, and dyspnea history. LAP methods were associated with a 1 day LOS benefit and significantly lower overall morbidity and lower rates of incisional and deep SSI, UTI, sepsis, and reoperations. Operative length was similar. The short-term results of the LAP approach are superior to the OPEN results.

Technique of last resort: characteristics of patients undergoing open surgery in the laparoscopic era.

BACKGROUND: The utilization rates for minimally invasive colorectal resection techniques (MICR) continue to increase. In some centers MICR methods are the preferred approach, however, open methods continue to be utilized for select patients. In this study, the profile and short-term outcomes of open colorectal resection (CR) and MICR patients are determined and compared. METHODS: A retrospective review of patients who underwent elective CR over 11 years at two institutions was performed. The MICR group contained both laparoscopic-assisted and hand-assisted cases. The past medical and surgical histories, indications, operations performed, and short-term outcomes were assessed. The Charlson co-morbidity index (CMI) was used to assess risk. RESULTS: During the study period 1080 patients underwent CR (Open, 141; MICR, 939). As judged by the CMI, there were more high-risk patients (score ≥2) in the Open group (34.38%) versus MICR (22.11%) p = 0.0029. Significantly more open patients had prior abdominal surgery and specifically CRs (Open, 15.60% vs. MICR, 2.13%, p < 0.001). Intraoperative transfusion (Open 25.7%; MICR 6.8%, p < 0.001) and diversion (25.53 vs. 11.50%, p < 0.001) were more common in the Open group. Not surprisingly, recovery of bowel function and length of stay were longer for the Open group. The overall complication rate was also higher for the Open patients (p < 0.001). CONCLUSION: When MICR is the procedure of choice, patients selected for Open CR are higher risk and more complex as judged by the CMI and past operative history. Not surprisingly, this translates into a longer length of stay, higher rates of transfusion, diversion, and complications. This disparity in patients undergoing CRs makes direct comparison of MICR and Open resection outcomes not reasonable.

The rate for the use of hand-assisted laparoscopic methods is directly proportional to body mass index.

BACKGROUND: Hand-assisted laparoscopic (HAL) colorectal resection remains controversial. Critics believe HAL methods lead to decreased use of laparoscopically assisted (LA) methods. Proponents believe selective HAL use increases minimally invasive surgery (MIS) use rates. This study assessed general and body mass index (BMI)-specific HAL and LA colorectal resection use by surgeons who embraced both methods. METHODS: This study retrospectively investigated 1,122 patients who underwent colorectal resection during an 8-year period. Surgical method, type of colorectal resection, BMI, comorbidities, incision length, and short-term outcomes were collected. RESULTS: The surgical methods included LA (60 %), HAL (25 %), and open (OP 15 %) procedures. The HAL group mean BMI was higher than that of the LA group (P < 0.0001), and the HAL use rate varied directly with BMI. The HAL technique was used for 48 % of the rectal, 36 % of the sigmoid, and 4 % of the right colorectal resections. The incision length was directly proportional to BMI for all the methods. Although the HAL incision lengths were significantly longer than the LA incision lengths for a BMI lower than 40 kg/m(2), there was no difference when the BMI was 40 kg/m(2) or higher. The comorbidities were greater in the HAL group than in the LA sigmoid colorectal resection group (P = 0.001). The mean hospital length of stay (LOS) was similar for the HAL and LA patients but longer for the open surgery patients (P < 0.0001 vs HAL group). The major complications, reoperations, and 30-day mortality rates were low and comparable. CONCLUSIONS: The HAL methods were used primarily for sigmoid and rectal colorectal resections and for higher BMI patients with more comorbidities. The mean incision length difference between the HAL and LA methods was 3.9 cm, but neither the LOS nor the major postoperative complications differed significantly. Selective use of HAL together with LA methods led to a MIS use rate of 85 % and facilitated MIS for high BMI patients. Together, the methods are complementary and may increase the number of minimally invasive surgeries performed.

Minimally invasive colorectal resection is associated with significantly elevated levels of plasma matrix metalloproteinase 3 (MMP-3) during the first month after surgery which may promote the growth of residual metastases.

INTRODUCTION: MMP-3, a member of the matrix metalloproteinase (MMP) family, is involved in the breakdown of the extracellular matrix in tissue remodeling and may also play a role in cancer progression and metastasis. Minimally invasive colorectal resection (MICR) may increase plasma MMP-3 levels directly via surgical trauma or indirectly due to surgery-associated elevations in TNF-α and IL1 which are regulators of MMP-3. This study's purpose was to evaluate plasma MMP-3 levels during the first month after MICR for colorectal cancer. METHODS: Patients enrolled in an IRB approved data/plasma bank who underwent elective MICR for CRC. Blood plasma samples had been collected preoperatively, on postoperative day (POD) 1, 3 and at varying postoperative time points and were stored at -80 °C. The late samples (POD 7-41) were bundled into 7 day time blocks and considered as single time points. MMP-3 levels were analyzed in duplicate via ELISA and the results reported as mean ± SD. The paired t test was used for analysis (significance, p < 0.008 after Bonferroni's correction). RESULTS: A total of 73 CRC patients who underwent MICR met the inclusion criteria. The mean PreOp MMP-3 level was 14.9 ± 7.8 ng/ml (n = 73). Significantly elevated mean plasma levels were noted on POD 1 (21.4 ± 14.7 ng/ml, n = 73, p < 0.0001), POD 3 (37.9 ± 21.5 ng/ml, n = 72, p < 0.0001), POD 7-13 (22.0 ± 13.0 ng/ml, n = 56, p < 0.0001), POD 14-20 (21.9 ± 10.3 ng/ml, n = 20, p = 0.003), and on POD 21-27 (21.9 ± 11.43 ng/ml, n = 20, p = 0.002) when compared to PreOp levels. Plasma levels returned to the PreOp baseline at the POD 28-41 time point (n = 16, p = 0.07). CONCLUSION: Plasma MMP-3 levels remained significantly elevated from baseline for 4 weeks after MICR for CRC. The early postoperative increase in MMP-3 levels may be due to the surgery-related acute inflammatory response; the elevation noted during weeks 2-3 may be related to wound healing. Increased MMP-3 levels may promote metastases or the growth of residual cancer.

Endoscopic tattooing to mark distal margin for low anterior rectal and select sigmoid resections.

Obtaining a reliable distal margin during anterior colorectal resection can be difficult. In this study, endoscopic transmural tattoos were placed to mark the distal transection point in patients with distal colorectal neoplasms who undergo bowel resection. In the operating room, before surgery, sigmoidoscopy is performed with a 2-channel scope using CO2 insufflation. Through channel 1, a biopsy forceps, marked 5 cm from its end, is inserted to the tumor's distal edge; in channel 2, a sclerotherapy catheter is placed. The scope is then withdrawn and forceps inserted at the same rate until the mark is seen, next, via the needle catheter, 4 tattoos are placed at that level circumferentially. After rectal mobilization, visible external tattoos guide stapler placement. If no tattoo is seen, sigmoidoscopy is done and the tattoos used to guide stapler placement. In all 27 patients, the tattoos guided stapler placement; tattoos were seen via the abdomen in 26 and the stapler placed as per tattoos in 25. In 2 patients, repeat endoscopy was done and tattoos used to guide or confirm stapler placement. The margin was ≤1 cm from target in 74% while in 22% the margin was 2 to 3.5 cm off target (mean deviation from target margin = 0.33 cm). In conclusion, this method facilitates stapler placement and provides more reliable margins.

Laparoscopic-facilitated endoscopic submucosal dissection, mucosal resection, and partial circumferential ("wedge") colon wall resection for benign colorectal neoplasms that come to surgery.

BACKGROUND: Large polyps that come to surgery are removed via colectomy (CR). Alternatives are MIS-facilitated endoscopic submucosal dissection/endoscopic mucosal resection (ESD/EMR) or wedge resection (WR). This study presents the results of 26 polyp patients who had minimally invasive surgery (MIS)-monitored ESD/EMR, WR, or if necessary, standard CR. METHODS: The authors used a retrospective review of 1 surgeon's experience. ESD/EMR was the first choice, WR was the second, and CR was the last resort. RESULTS: Polyp locations were as follows: right/transverse, 16 (62%); rectum, 7 (27%); and left/sigmoid, 3 (12%). ESD/EMR was successful in 13 patients and WR in 4; 9 patients required CR. Median flatus times were as follows: ESD/EMR, 1 day; WR, 2 days; and CR, 3 days (ESD/EMR vs CR, P = .01). Median length of stay was as follows: ESD/EMR, 3 days; WR, 5 days; and CR, 5 days (ESD/EMR vs CR, P = .0037). There were no leaks or abscesses. Carcinoma was found in 3 patients. Postoperatively, 2 ESD/EMR patients had residual polyp fully removed via a scope. CONCLUSIONS: ESD/EMR and WR appear to be safe but techniques are evolving. Larger studies are needed.

Compared to preoperative plasma levels post-operative urokinase-type plasminogen activator-1 levels are persistently elevated for 6 weeks after minimally invasive colorectal resection.

Background: Urokinase-type plasminogen activator-1 (uPA) is a serine protease that converts plasminogen to plasmin after binding to uPA receptor (uPAR). Plasmin catalyzes the regeneration of basement membrane, extracellular matrix, and other tissues. uPA alone and with plasmin leads to activation of angiogenic growth factors that impact tumor cell proliferation, adhesion, and migration. uPA over expression has been noted in colorectal cancer (CRC) and high tissue levels have been correlated with prognosis. uPA/uPAR promotes immune cell activation in healing surgical wounds and may alter perioperative uPA plasma levels. Postoperative (postop) plasma levels, if elevated, may impact the early growth of residual metastases. The impact of minimally invasive colorectal resection (MICR) surgery for CRC on plasma uPA levels is unknown. This study's aim was to measure plasma uPA levels during the first postop month. Methods: CRC patients undergoing MICR who enrolled in an Institutional Review Board (IRB) approved data/plasma bank for whom adequate plasma was available were included in the study. Patients who had chemotherapy or radiotherapy within 4 weeks, those who received blood transfusions perioperatively and immunosuppressed patients were excluded. Clinical and pathological data were prospectively collected as were blood samples preoperatively, postop day (POD) 1, 3 and at least 1 late time point between POD 7-41. Plasma was isolated and stored at -80 ℃. Late samples were bundled into 7-day blocks and considered as single time points. Total uPA levels (ng/mL) were analyzed in duplicate via enzyme-linked immunosorbent assay (ELISA) and results reported as mean ± standard deviation (SD). The Wilcoxon paired t-test was used for analysis. Results: Ninety-three patients undergoing MICR for CRC [colonic 68%; rectal 32%; average age 65.6 years, laparoscopic 63%, hand-assisted minimally invasive surgery (MIS) 37%] who met criteria were studied. Cancer stage breakdown was; stage I, 30%, stage II, 29%, stage III, 34%, stage IV, 7%. The median preoperative (preop) uPA plasma level (ng/mL) was 529.8 [95% confidence interval (CI): 462.8, 601.1] (n=93). Significant elevations in median levels vs. preop were present during POD 3 (542.8, 95% CI: 518.8, 597.3, n=86, P=0.003), POD 7-13 (688.1, 95% CI: 591.7, 753.0, n=72, P<0.001), POD 14-20 (764.9, 95% CI: 704.1, 911.6, n=27, P<0.001), POD 21-27 (685.6, 95% CI: 443.8, 835.8, n=15, P<0.001), and on POD 28-41 (800.3, 95% CI: 626.9, 940.6, n=21, P<0.001). The colon cancer subgroup's preop and POD 14-20 median results were significantly higher than the corresponding rectal cancer results; otherwise, at the other 5 postop time points there were no significant differences between the rectal and colon cancer subgroups. In addition, no association was found between cancer stage and preop uPA levels and no significant differences were found in postop uPA levels between the hand-assisted laparoscopic group and the lap assisted subgroup at any of the postop time points. Conclusions: Persistently elevated plasma uPA levels at 5/6 postop time point (P<0.05), in combination with other previously demonstrated long duration proangiogenic plasma protein changes, may render the plasma proangiogenic within the period of the first month post-surgery and may promote angiogenesis within the residual tumor foci. The clinical significance pertaining to these changes, if any, is uncertain and remains to be proven.

MAGE-A3 is highly expressed in a subset of colorectal cancer patients.

The expression of Cancer/Testis (CT) antigens in some tumors and restricted expression in normal tissue make CT antigens attractive vaccine targets. We evaluated the expression of MAGE-A3, PLAC1, GAGE, and CTAG2 in a series of colorectal cancers (CRC). CT mRNA expression was determined via quantitative PCR on paired tumors and normal tissue samples from 82 CRC patients. In addition, plasma antibody titers specific to MAGE-A3, PLAC1, GAGE, and CTAG2 were determined via ELISA. Tissue expression of MAGE-A3 was assessed via a standard IHC protocol. The Student's t-test was used for statistical analysis (significance p < 0.05). Tumor expression of MAGE-A3, CTAG2, and GAGE was compared to the levels of expression in testis. The percentage of samples that had a tumor vs. testis expression ratio above 0.1% was: MAGE-A3 (28%) and CTAG2 (17%) but no tumor presented GAGE expression levels above 0.1%. The expression levels of PLAC1 in tumors were compared to the levels in placenta, and in 12.8% of the samples analyzed, these levels were above 0.1%. Sero-reactivity specific for MAGE-A genes and PLAC1 was noted in 2.4% and 2.6% of patients, respectively. MAGE-A3 and PLAC1 may hold promise as vaccine targets for CRC. Further study is warranted.

Plasma levels of angiopoietin-like protein 4 (ANGPTL4) are significantly lower preoperatively in colorectal cancer patients than in cancer-free patients and are further decreased during the first month after minimally invasive colorectal resection.

BACKGROUND: Surgery has been associated with proangiogenic plasma protein changes that may promote tumor growth. Angiopoietin-like protein 4 (ANGPTL4) is expressed by endothelial cells and other tissues in response to hypoxia. Both intact ANGPTL4 and its partly degraded C-terminal fragment may promote tumor angiogenesis. This study had two purposes: to measure and compare preoperative plasma ANGPTL4 levels in patients with colorectal cancer (CRC) and benign colorectal disease (BCD) and to determine plasma levels after minimally invasive colorectal resection (MICR) for CRC. METHODS: Plasma was obtained from an IRB-approved plasma/data bank. Preoperative plasma ANGPTL4 levels were measured for CRC and BCD patients, but postoperative levels were determined only for CRC patients for whom a preoperative, a postoperative day (POD) 3, and at least one late postoperative sample (POD 7-55) were available. Late samples were bundled into four time blocks and considered as single time points. ANGPTL4 levels (mean ± SD) were measured via ELISA and compared (significance, p < 0.01 after Bonferroni correction). RESULTS: Eighty CRC (71 % colon, 29 % rectal) and 60 BCD (62 % diverticulitis, 38 % adenoma) patients were studied. The mean preoperative plasma ANGPTL4 level in CRC patients (247.2 ± 230.7 ng/ml) was lower than the BCD group result (330.8 ± 239.0 ng/ml, p = 0.01). There was an inverse relationship between plasma levels and advanced CRC as judged by three criteria. In regard to the postoperative CRC analysis, the "n" for each time point varied: lower plasma levels (p < 0.001) were noted on POD 3 (161.4 ± 140.4 ng/ml, n = 80), POD 7-13 (144.6 ± 134.5 ng/ml, n = 46), POD 14-20 (139.0 ± 117.8 ng/ml, n = 27), POD 21-27 (138.9 ± 202.4, n = 20), and POD 28-55 (160.1 ± 179.0, n = 42) when compared to preoperative results. CONCLUSION: CRC is associated with lower preoperative plasma ANGPTL4 levels compared with BCD, and the levels may vary inversely with disease severity. After MICR for CRC, levels are significantly lower for over a month compared with the preoperative level; the cause for this persistent decrease is unclear. The implications of both the lower preoperative level and the persistently decreased postoperative levels are unclear. Further studies are needed.

Sustained postoperative plasma elevations of plasminogen activator inhibitor-1 following minimally invasive colorectal cancer resection.

Plasminogen activator inhibitor-1 (PAI-1) is a serine protease inhibitor that inhibits urokinase-type plasminogen activator and tissue-type plasminogen activator. PAI-1 participates in angiogenesis, wound healing and tumor invasion, and additionally regulates endothelial cell proliferation, angiogenesis and tumor growth. The purpose of the present study was to measure plasma PAI-1 levels perioperatively in patients with colorectal cancer (CRC) undergoing minimally invasive colorectal resection (MICR). Patients with CRC who underwent elective MICR were eligible for the study. All patients were enrolled in an approved data/plasma bank. Patients with preoperative, postoperative day (POD) 1, POD 3, and at least one POD 7-34 plasma sample collection were studied. Plasma PAI-1 levels were determined in duplicate using ELISA, and the medians and 95% confidence intervals (CIs) were determined. The correlations between postoperative plasma PAI-1 levels and length of surgery were evaluated. PAI-1 levels were compared between patients who underwent laparoscopic-assisted vs. hand-assisted surgery. The preoperative PAI-1 levels of stage I, II, III and IV pathological stage subgroups were also compared. A total of 91 patients undergoing MICR for CRC were studied. The mean incision length was 8.0±3.9 cm, and the length of stay was 6.8±4.3 days. Compared with the median preoperative levels (17.30; 95% CI: 15.63-19.78 ng/ml), significantly elevated median levels were observed on POD 1 (28.86; 95% CI: 25.46-31.22 ng/ml; P<0.001), POD 3 (18.87; 95% CI: 17.05-21.78 ng/ml; P=0.0037), POD 7-13 (26.97; 95% CI: 22.81-28.74 ng/ml; P<0.001), POD 14-20 (25.92; 95% CI: 17.85-35.89 ng/ml; P=0.001) and POD 21-27 (22.63; 95% CI: 20.03-30.09 ng/ml; P<0.001). The PAI-1 levels in the hand-assisted group were higher compared with those in the laparoscopic-assisted group for 4 weeks after surgery; however, a significant difference was found only on POD 1. Therefore, plasma PIA-1 levels were found to be significantly elevated for 4 weeks after MICR, and the surgery-related acute inflammatory response may account for the early postoperative PIA-1 increase. Furthermore, PAI-1-associated VEGF-induced angiogenesis in the healing wounds may account for the late postoperative elevations, and increased PAI-1 levels may promote angiogenesis in residual tumor deposits.

Plasma MMP-2 and MMP-7 levels are elevated first month after surgery and may promote growth of residual metastases.

BACKGROUND: MMP-2 also known as gelatinase A and MMP-7 (matrilysin) are members of the zinc-dependent family of MMPs (Matrix metalloproteinase). MMP-2 and MMP-7 are remodeling enzymes that digest extracellular matrix; MMP-2 is extensively expressed during development and is upregulated at sites of tissue damage, inflammation, and in stromal cells of metastatic tumors. MMP-7 is expressed in the epithelial cells and in a variety of cancers including colon tumors. Plasma MMP-2 and MMP-7 levels were assessed before and after minimally invasive colorectal resection for cancer pathology. AIM: To determine plasma MMP-2 and MMP-7 levels before and after minimally invasive colorectal resection for cancer pathology. METHODS: Patients enrolled in a plasma bank for whom plasma was available were eligible. Plasma obtained from preoperative (Preop) and postoperative blood samples was used. Only colorectal cancer (CRC) patients who underwent elective minimally invasive cancer resection with preop, post-operative day (POD) 1, 3 and at least 1 late postop sample (POD 7-34) were included. Late samples were bundled into 7 d blocks (POD 7-13, 14-20, etc.) and treated as single time points. Plasma MMP-2 and MMP-7 levels were determined via enzyme-linked immunosorbent assay in duplicate. RESULTS: Total 88 minimally invasive CRC resection CRC patients were studied (right colectomy, 37%; sigmoid, 24%; and LAR/AR 18%). Cancer stages were: 1, 31%; 2, 30%; 3, 34%; and 4, 5%. Mean Preop MMP-2 plasma level (ng/mL) was 179.3 ± 40.9 (n = 88). Elevated mean levels were noted on POD1 (214.3 ± 51.2, n = 87, P < 0.001), POD3 (258.0 ± 63.9, n = 80, P < 0.001), POD7-13 (229.9 ± 62.3, n = 65, P < 0.001), POD 14-20 (234.9 ± 47.5, n = 25, P < 0.001), POD 21-27 (237.0 ± 63.5, n = 17, P < 0.001,) and POD 28-34 (255.4 ± 59.7, n = 15, P < 0.001). Mean Preop MMP-7 level was 3.9 ± 1.9 (n = 88). No significant differences were noted on POD 1 or 3, however, significantly elevated levels were noted on POD 7-13 (5.7 ± 2.5, n = 65, P < 0.001), POD 14-20 (5.9 ± 2.5, n = 25, P < 0.001), POD 21-27 (6.1 ± 3.6, n = 17, P = 0.002) and on POD 28-34 (6.8 ± 3.3, n = 15 P < 0.001,) vs preop levels. CONCLUSION: MMP-2 levels are elevated for 5 wk and MMP-7 levels elevated for weeks 2-6. The etiology of these changes in unclear, trauma and wound healing likely play a role. These changes may promote residual tumor growth and metastasis.

Plasma Levels of Keratinocyte Growth Factor Are Significantly Elevated for 5 Weeks After Minimally Invasive Colorectal Resection Which May Promote Cancer Recurrence and Metastasis.

Background: Human Keratinocyte Growth Factor (KGF) is an FGF family protein produced by mesenchymal cells. KGF promotes epithelial cell proliferation, plays a role in wound healing and may also support tumor growth. It is expressed by some colorectal cancers (CRC). Surgery's impact on KGF levels is unknown. This study's purpose was to assess plasma KGF levels before and after minimally invasive colorectal resection (MICR) for CRC. Aim: To determine plasma KGF levels before and after minimally invasive colorectal resection surgery for cancer pathology. Method: CRC MICR patients (pts) in an IRB approved data/plasma bank were studied. Pre-operative (pre-op) and post-operative (post-op) plasma samples were taken/stored. Late samples were bundled into 7 day blocks and considered as single time points. KGF levels (pg/ml) were measured via ELISA (mean ± SD). The Wilcoxon paired t-test was used for statistical analysis. Results: Eighty MICR CRC patients (colon 61%; rectal 39%; mean age 65.8 ± 13.3) were studied. The mean incision length was 8.37 ± 3.9 and mean LOS 6.5 ± 2.6 days. The cancer stage breakdown was; I (23), II (26), III (27), and IV (4). The median pre-op KGF level was 17.1 (95 %CI: 14.6-19.4; n = 80); significantly elevated (p < 0.05) median levels (pg/ml) were noted on post-op day (POD) 1 (23.4 pg/ml; 95% CI: 21.4-25.9; n = 80), POD 3 (22.5 pg/ml; 95% CI: 20.7-25.9; n = 76), POD 7-13 (21.8 pg/ml; 95% CI: 17.7-25.4; n = 50), POD 14-20 (20.1 pg/ml; 95% CI: 17.1-23.9; n = 33), POD 21-27 (19.6 pg/ml; 95% CI: 15.2-24.9; n = 15) and on POD 28-34 (16.7 pg/ml; 95% CI: 14.0-25.8; n = 12). Conclusion: Plasma KGF levels were significantly elevated for 5 weeks after MICR for CRC. The etiology of these changes is unclear, surgical trauma related acute inflammatory response and wound healing process may play a role. These changes, may stimulate angiogenesis in residual tumor deposits after surgery.

The cancer testis antigens CABYR-a/b and CABYR-c are expressed in a subset of colorectal cancers and hold promise as targets for specific immunotherapy.

INTRODUCTION: Calcium-binding tyrosine phosphorylation-regulated protein (CABYR) is expressed in the human germ line but not in adult human tissues, thus, it is considered a cancer testis protein. The aim of this study is to evaluate the CABYR isoforms: a/b and c mRNA expression in colorectal cancer (CRC) and to determine if these proteins hold promise as vaccine targets. MATERIALS AND METHODS: CABYR mRNA expression in a set of normal human tissues, including the testis, were determined and compared using semi-quantitative PCR. As regards the tumor and normal mucosal samples from study patients, RNA was extracted and cDNA generated after which quantitative PCR was carried out. Analysis of CABYR protein expressions by immunohistochemistry in tumor and normal colon tissues was also performed. RESULTS: A total of 47 paired CRC and normal tissue specimens were studied. The percent of patients with a relative expression ratio of malignant to normal (M/N) tissues over 1 was 70% for CABYR a/b and 72% for CABYR c. The percent with both a M/N ratio over 1 and expression levels over 0.1% of testis was 23.4% for CABYR-a/b and 25.5% for CABYR c. CABYR expression in tumors was further confirmed by immunohistochemistry. CONCLUSIONS: CABYR a/b and c hold promise as specific immunotherapy targets, however, a larger and more diverse group of tumors (Stage 1-4) needs to be assessed and evaluation of blood for anti-CABYR antibodies is needed to pursue this concept.

Minimally invasive colorectal resection is associated with a rapid and sustained decrease in plasma levels of epidermal growth factor (EGF) in the colon cancer setting.

BACKGROUND: Epidermal growth factor (EGF) stimulates tumor growth directly via tumor cell EGF receptors or indirectly via its proangiogenic effects. This study's purpose was to determine the impact of minimally invasive colorectal resection (MICR) on postoperative (postop) plasma EGF levels in the colorectal cancer (CRC) and benign disease settings and to see if preoperative (PreOp) EGF levels are altered in cancer patients. METHODS: MICR patients with benign pathology (n = 40) and CRC (n = 48) had blood samples taken PreOp and on postoperative days (POD) 1 and 3. In some patients, late samples were taken between POD7 and POD60; these were bundled into 7-day blocks and considered as single time points. EGF levels were determined by enzyme-linked immunosorbent assay (ELISA) and results were reported as mean ± SD after logarithmic transformation. The Student t test was used (p < 0.008 after Bonferroni correction). RESULTS: The cancer and benign groups were comparable except for age. The mean PreOp CRC plasma EGF level (122.9 ± 75.9 pg/ml) was significantly higher than that of the benign group (85.3 ± 38.5 pg/ml) (p = 0.015). The cancer group's EGF levels were significantly decreased on POD1 and POD3 and for the POD31-55 time point (mean EGF level = 63.1 ± 42.2 (n = 10). The benign group's POD3 and POD7-14 EGF levels were significantly lower than the PreOp level; later levels returned toward baseline. Small late sample size limited analysis. CONCLUSION: Plasma EGF levels are significantly higher in cancer patients. MICR is associated with a significant decrease in EGF levels early postop in both cancer and benign settings. Unlike the benign group, EGF blood levels in cancer patients remain low during the second postop month. A larger study with more late samples is needed to verify these results. EGF may have value as a tumor marker.