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In recent years, the rise of minimally invasive surgery has driven the development of surgical devices. Indocyanine green (ICG) fluorescence imaging is receiving increased attention in colorectal surgery for improved intraoperative visualization and decision-making. ICG, approved by the U.S. Food and Drug Administration in 1959, rapidly binds to plasma proteins and is primarily intravascular. ICG absorption of near-infrared light (750–800 nm) and emission as fluorescence (830 nm) when bound to tissue proteins enhances deep tissue visualization. Applications include assessing anastomotic perfusion, identifying sentinel lymph nodes, and detecting colorectal cancer metastasis. However, standardized protocols and research on clinical outcomes remain limited. This study explores ICG’s role, advantages, disadvantages, and potential clinical impact in colorectal surgery.
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Purpose@#Recent studies have revealed that the expression of cancer-associated fibroblast (CAF) activation biomarkers in cancer cells is associated with clinical outcomes in patients with certain types of malignant tumors. However, whether the expression of CAF activation biomarkers affects the prognosis of colorectal cancer (CRC) has not been fully elucidated. This study aimed to evaluate the association between the expression of CAF activation biomarkers in cancer cells with cancer invasion and long-term oncological outcomes in patients with CRC. @*Methods@#Cancer specimens obtained from 135 patients with stage I–III CRC were examined using immunohistochemical staining to evaluate the expression of fibroblast specific protein-1 (FSP-1), fibroblast activation protein α (FAPα), α-smooth muscle actin (α-SMA), and vimentin in cancer cells. @*Results@#FSP-1 expression in cancer cells was significantly associated with lymphatic invasion, perineural invasion, tumor (T) status, and lymph node (N) status. FAPα expression in cancer cells was significantly associated with lymphatic invasion. On univariate and multivariate analyses, FSP-1 and α-SMA expression in cancer cells were associated with a short 10-year overall survival (OS) and high 10-year systemic recurrence (SR), respectively. Tumor budding was associated with a short 10-year OS. However, FAPα and vimentin did not contribute to the prognosis in this study. @*Conclusion@#In this study, we found that FSP-1 expression in cancer cells was related to cancer invasion. Additionally, FSP-1 and α-SMA expression in cancer cells was associated with 10-year OS and SR, respectively. Therefore, these markers may be used as predictors of long-term oncological outcomes in patients with CRC.
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Vascular invasion is an unfavorable prognostic factor for the recurrence and systemic metastasis of colon cancer. An interesting study in this issue evaluate the difference in the oncological impact of vascular invasion according to tumor side in colon cancer. The authors suggest that the oncological impact of vascular invasion could be worse in nonmetastatic right colon cancer than in nonmetastatic left colon cancer. Herein, hematoxylin-eosin staining was used to detect vascular invasion. In a recent study, elastin staining could detect more venous invasion. It is expected that the molecular pathologic characteristics of colon cancer can be identified precisely and the oncological outcomes of colon cancer can be improved in the future.
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Colon cancer treatment is on the way to evolution over several decades. The minimally invasive surgery has improved postoperative short-term outcomes. Adjuvant chemotherapy has prolonged the survival of advanced colon cancer patients. Hohenberger proposed the noble concept of complete mesocolic excision (CME) which consists of 3 components: plane surgery, sufficient longitudinal bowel resection, and central vascular ligation (CVL). Mesocolic plane surgery shares the same surgical principle of total mesorectal excision, which is maintaining the intact mesothelial envelope. However, there remain debates about the extent of bowel resection and the level of CVL for maximizing lymph node dissection. There is no solid clinical evidence for the oncological necessity and benefit of extended radical dissection in right hemicolectomy. CME with CVL based on open surgery has been adopted in laparoscopic surgery. So, it is also necessary to look at how the CME could be transformed and successfully implanted in the laparoscopic era. Recent rapid advances in surgical technology and cancer biology are preparing for fundamental changes in cancer surgery. In this study, we reviewed the history, oncological necessity, and compatibility of CME for the right hemicolectomy in the laparoscopic era and outline the new perspectives on the evolution of cancer surgery.
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Purpose@#Rectal neuroendocrine tumors (NETs) <10 mm are endoscopically resected, while those ≥20 mm are treated with radical surgical resection. The choice of treatment for 10–20 mm sized rectal NETs remains controversial. This study aimed to verify factors predicting lymph node metastasis (LNM) of 10–20 mm sized rectal NET and utilize them to decide upon the treatment strategy. @*Methods@#Twenty-eight patients with 10–20 mm sized rectal NETs treated at Pusan National University Yangsan Hospital from January 2009 to September 2020 were divided into LNM (+) and LNM (–) groups, and their respective data were analyzed. @*Results@#Seven patients (25%) had LNM while 21 patients (75%) did not. Endorectal ultrasound findings showed tumor size was significantly larger in the LNM (+) than in the LNM (–) group (15 mm vs. 10 mm, P=0.018); however, pathologically, there was no significant difference in tumor size (13 mm vs. 11 mm, P=0.109). The mitotic count (P=0.011), Ki-67 index (P=0.008), and proportion of tumor grade 2 patients (5 cases, 71% vs. 1 case, 5%; P=0.001) were significantly higher in the LNM (+) group. In multivariate analysis, tumor grade 2 was the independent factor predicting LNM (odds ratio, 61.32; 95% confidence interval, 3.17–1,188.64; P=0.010). @*Conclusion@#Tumor grade 2 was the independent factor predicting LNM in 10–20 mm sized rectal NETs. Therefore, it could be considered as the meaningful factor in determining whether radical resection is necessary.
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Anastomotic complications occur after 5% to 20% of operations for rectosigmoid colon cancer. The intestinal perfusion status at the anastomotic site is an important modifiable risk factor, and surgeons should carefully evaluate and optimize the perfusion at the intended site of anastomosis. Indocyanine green (ICG) angiography is a simple noninvasive perfusion assessment modality. The use of ICG angiography is rapidly spreading in the field of colorectal surgery. However, there is debate on its contribution to reducing anastomotic complications. In this review, we discuss the clinical utility and the standardization of ICG angiography. ICG angiography can unequivocally reveal unfavorable perfusion zones and provide quantitative parameters to predict the risk of hypoperfusion-related anastomotic complications. Many studies have demonstrated the clinical utility of ICG angiography for reducing anastomotic complications. Recently, two multicenter randomized clinical trials reported that ICG angiography did not significantly reduce the incidence of anastomotic leakage. Most previous studies have been small-scale single-center studies, and there is no standardized ICG angiography protocol to date.Additionally, ICG angiography evaluations have mostly relied on surgeons’ subjective judgment. For these reasons, it is necessary to establish a standardized ICG angiography protocol and develop a quantitative analysis protocol for the objective assessment. In conclusion, ICG angiography could be useful for detecting poorly perfused colorectal segments to prevent anastomotic leakage after colorectal surgery. An optimized and standardized ICG angiography protocol should be established to improve the reliability of perfusion assessments. In the future, artificial intelligence-based quantitative analyses could be used to easily assess colonic perfusion status.
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Indocyanine green (ICG) could be applied for multiple functions such as fluorescent tumor localization, fluorescence lymph node mapping (FLNM), and intraoperative angiography in colorectal cancer surgery. With the near-infrared (NIR) systems, colonoscopic ICG tattooing can be used to define the early colorectal cancer that cannot be easily distinguished through the serosal surface. The lymphatic pathways can be visualized under the NIR system when ICG is injected through the submucosal or subserosal layer around the tumor. Intraoperative ICG angiography can be applied to find a favorable perfusion segment before the colon transection. Although all fluorescence functions are considered essential steps in image-guided surgery, it is difficult to perform multifunctional ICG applications in a single surgical procedure at once because complex protocols could interfere with each other. Therefore, we review the multifunctional ICG applications for fluorescent tumor localization, FLNM, and ICG angiography. We also discuss the optimal protocol for fluorescence-guided colorectal surgery.
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Synchronous quadruple colorectal cancer (CRC) is extremely rare without genetic alterations. We present a case of synchronous quadruple CRC with 2 lesions previously obscured by ischemic colitis. A 73-year-old woman was admitted to our emergency department. An abdominal computed tomography revealed ischemic colitis and irregular wall thickening of the sigmoid colon and sigmoid-descending junction, suspicious of 2 colon cancers. A colonoscopy examination revealed a fungating mass 20 cm from the anal verge, as well as ischemic colitis spanning the mucosa from the sigmoid colon to the transverse colon. The patient underwent laparoscopic Hartmann procedure. Pathologic examination confirmed both lesions as adenocarcinomas with microsatellite stable. Seven months postoperatively, instead of a laparoscopic Hartmann reversal, a laparoscopic total colectomy was performed due to the continued presence of severe ischemic colitis. The pathologic report suggested the presence of 2 distinct invasive adenocarcinomas in the descending colon without genetic alterations such as microsatellite instability.
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Purpose@#Rectal neuroendocrine tumors (NETs) <10 mm are endoscopically resected, while those ≥20 mm are treated with radical surgical resection. The choice of treatment for 10–20 mm sized rectal NETs remains controversial. This study aimed to verify factors predicting lymph node metastasis (LNM) of 10–20 mm sized rectal NET and utilize them to decide upon the treatment strategy. @*Methods@#Twenty-eight patients with 10–20 mm sized rectal NETs treated at Pusan National University Yangsan Hospital from January 2009 to September 2020 were divided into LNM (+) and LNM (–) groups, and their respective data were analyzed. @*Results@#Seven patients (25%) had LNM while 21 patients (75%) did not. Endorectal ultrasound findings showed tumor size was significantly larger in the LNM (+) than in the LNM (–) group (15 mm vs. 10 mm, P=0.018); however, pathologically, there was no significant difference in tumor size (13 mm vs. 11 mm, P=0.109). The mitotic count (P=0.011), Ki-67 index (P=0.008), and proportion of tumor grade 2 patients (5 cases, 71% vs. 1 case, 5%; P=0.001) were significantly higher in the LNM (+) group. In multivariate analysis, tumor grade 2 was the independent factor predicting LNM (odds ratio, 61.32; 95% confidence interval, 3.17–1,188.64; P=0.010). @*Conclusion@#Tumor grade 2 was the independent factor predicting LNM in 10–20 mm sized rectal NETs. Therefore, it could be considered as the meaningful factor in determining whether radical resection is necessary.
ABSTRACT
Anastomotic complications occur after 5% to 20% of operations for rectosigmoid colon cancer. The intestinal perfusion status at the anastomotic site is an important modifiable risk factor, and surgeons should carefully evaluate and optimize the perfusion at the intended site of anastomosis. Indocyanine green (ICG) angiography is a simple noninvasive perfusion assessment modality. The use of ICG angiography is rapidly spreading in the field of colorectal surgery. However, there is debate on its contribution to reducing anastomotic complications. In this review, we discuss the clinical utility and the standardization of ICG angiography. ICG angiography can unequivocally reveal unfavorable perfusion zones and provide quantitative parameters to predict the risk of hypoperfusion-related anastomotic complications. Many studies have demonstrated the clinical utility of ICG angiography for reducing anastomotic complications. Recently, two multicenter randomized clinical trials reported that ICG angiography did not significantly reduce the incidence of anastomotic leakage. Most previous studies have been small-scale single-center studies, and there is no standardized ICG angiography protocol to date.Additionally, ICG angiography evaluations have mostly relied on surgeons’ subjective judgment. For these reasons, it is necessary to establish a standardized ICG angiography protocol and develop a quantitative analysis protocol for the objective assessment. In conclusion, ICG angiography could be useful for detecting poorly perfused colorectal segments to prevent anastomotic leakage after colorectal surgery. An optimized and standardized ICG angiography protocol should be established to improve the reliability of perfusion assessments. In the future, artificial intelligence-based quantitative analyses could be used to easily assess colonic perfusion status.
ABSTRACT
Indocyanine green (ICG) could be applied for multiple functions such as fluorescent tumor localization, fluorescence lymph node mapping (FLNM), and intraoperative angiography in colorectal cancer surgery. With the near-infrared (NIR) systems, colonoscopic ICG tattooing can be used to define the early colorectal cancer that cannot be easily distinguished through the serosal surface. The lymphatic pathways can be visualized under the NIR system when ICG is injected through the submucosal or subserosal layer around the tumor. Intraoperative ICG angiography can be applied to find a favorable perfusion segment before the colon transection. Although all fluorescence functions are considered essential steps in image-guided surgery, it is difficult to perform multifunctional ICG applications in a single surgical procedure at once because complex protocols could interfere with each other. Therefore, we review the multifunctional ICG applications for fluorescent tumor localization, FLNM, and ICG angiography. We also discuss the optimal protocol for fluorescence-guided colorectal surgery.
ABSTRACT
Synchronous quadruple colorectal cancer (CRC) is extremely rare without genetic alterations. We present a case of synchronous quadruple CRC with 2 lesions previously obscured by ischemic colitis. A 73-year-old woman was admitted to our emergency department. An abdominal computed tomography revealed ischemic colitis and irregular wall thickening of the sigmoid colon and sigmoid-descending junction, suspicious of 2 colon cancers. A colonoscopy examination revealed a fungating mass 20 cm from the anal verge, as well as ischemic colitis spanning the mucosa from the sigmoid colon to the transverse colon. The patient underwent laparoscopic Hartmann procedure. Pathologic examination confirmed both lesions as adenocarcinomas with microsatellite stable. Seven months postoperatively, instead of a laparoscopic Hartmann reversal, a laparoscopic total colectomy was performed due to the continued presence of severe ischemic colitis. The pathologic report suggested the presence of 2 distinct invasive adenocarcinomas in the descending colon without genetic alterations such as microsatellite instability.
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Purpose@#Patients who undergo radical surgery for rectal cancer often experience low anterior resection syndrome (LARS). Symptoms of this syndrome include frequent bowel movements, gas incontinence, fecal incontinence, fragmentation, and urgency. The aim of this study was to investigate the convergent validity, discriminative validity, and reliability of the Korean version of the LARS score questionnaire. @*Methods@#The English LARS score questionnaire was translated into Korean using the forward-and-back translation method. A total of 146 patients who underwent radical surgery for rectal cancer answered the Korean version of the LARS score questionnaire including an anchor question assessing the impact of bowel function. Participants answered the questionnaire once more after 2 weeks. @*Results@#The Korean LARS score questionnaire showed high convergent validity in terms of high correlation between the LARS score and quality of life (perfect fit 55.5% vs. moderate fit 37.6% vs. no fit 6.8%, respectively; P 8 cm; P = 0.021), and radiotherapy (32 for yes vs. 24 for no; P = 0.001). The LARS score also demonstrated high reliability at test-retest with no difference between scores at the first and second tests (intraclass correlation coefficient: Q1 = 0.932; Q2 = 0.909, Q3 = 0.944, Q4 = 0.931, and Q5 = 0.942; P < 0.001, respectively). @*Conclusion@#The Korean version of the LARS score questionnaire has proven to be a valid and reliable tool for measuring LARS in Korean patients with rectal cancer.
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An extragastrointestinal stromal tumor (EGIST) is a gastrointestinal stromal tumor that arises outside of the gastrointestinal tract. Most EGISTs are located in the omentum, mesentery, and retroperitoneum. The occurrence of an EGIST at the perianal region is very rare. Herein, we report our experience with EGISTs in the perianal area and review the literature. A 70-year-old man presented to our hospital with a 2-year history of anal discomfort. A pelvic magnetic resonance imaging scan showed a homogenous, well-defined, soft tissue density mass. The patient underwent mass excision, and the pathological examination confirmed that the mass was an EGIST. The size of the tumor was 4.3×3.2 cm, and the mitotic count was 1 per 50 high-power fields. The tumor cells were immunohistochemically positive for KIT and CD34 but were negative for S-100 and alpha-smooth muscle actin. There were no other abnormal findings in the gastrointestinal tract; upon pathological review, this case was confirmed as perianal EGIST. Therefore, EGIST should be considered as a differential diagnosis of perianal masses.
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Purpose@#This preliminary in-vitro study was designed to evaluate the risk factors of compression injury from use of a circular stapler for end-to-end anastomosis. @*Methods@#Transparent collagen plates were prepared in dry and wet conditions. Physical properties of collagen plates and porcine colon tissue were examined using a rheometer. Adjustable and fixed-type circular staplers were applied on the collagen plates and the gap distance and compressive pressure were measured during anvil approximation. Tissue injury was evaluated using a compression injury scale. Compression properties were accessed to optimal or overcompression based on gap distance. @*Results@#Unacceptable injuries were rarely observed on the dry collagens, regardless of compression device. In the adjustable compression, the compressibility ratio was similar between dry and wet collagen. Overcompression and unacceptable injury increased on the wet collagens. In the fixed compression, the compressibility ratio increased significantly and unacceptable injuries were observed in more than 50% of wet collagens. Peak pressure was significantly higher in the fixed-compression types than those of adjustable type. On bivariate correlation analysis, fixed-compression type and wet collagens were respectively associated with overcompression. On multivariate analysis, edematous collagen condition was the most important risk factor and proximal anvil side, fixed compression type, and overcompression were also independent risk factors for unacceptable compression injury. @*Conclusion@#In the edematous tissue condition, unintentional overcompression could be increased and result in tissue injury on the compression line of the circular stapler.
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An extragastrointestinal stromal tumor (EGIST) is a gastrointestinal stromal tumor that arises outside of the gastrointestinal tract. Most EGISTs are located in the omentum, mesentery, and retroperitoneum. The occurrence of an EGIST at the perianal region is very rare. Herein, we report our experience with EGISTs in the perianal area and review the literature. A 70-year-old man presented to our hospital with a 2-year history of anal discomfort. A pelvic magnetic resonance imaging scan showed a homogenous, well-defined, soft tissue density mass. The patient underwent mass excision, and the pathological examination confirmed that the mass was an EGIST. The size of the tumor was 4.3×3.2 cm, and the mitotic count was 1 per 50 high-power fields. The tumor cells were immunohistochemically positive for KIT and CD34 but were negative for S-100 and alpha-smooth muscle actin. There were no other abnormal findings in the gastrointestinal tract; upon pathological review, this case was confirmed as perianal EGIST. Therefore, EGIST should be considered as a differential diagnosis of perianal masses.
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Purpose@#This preliminary in-vitro study was designed to evaluate the risk factors of compression injury from use of a circular stapler for end-to-end anastomosis. @*Methods@#Transparent collagen plates were prepared in dry and wet conditions. Physical properties of collagen plates and porcine colon tissue were examined using a rheometer. Adjustable and fixed-type circular staplers were applied on the collagen plates and the gap distance and compressive pressure were measured during anvil approximation. Tissue injury was evaluated using a compression injury scale. Compression properties were accessed to optimal or overcompression based on gap distance. @*Results@#Unacceptable injuries were rarely observed on the dry collagens, regardless of compression device. In the adjustable compression, the compressibility ratio was similar between dry and wet collagen. Overcompression and unacceptable injury increased on the wet collagens. In the fixed compression, the compressibility ratio increased significantly and unacceptable injuries were observed in more than 50% of wet collagens. Peak pressure was significantly higher in the fixed-compression types than those of adjustable type. On bivariate correlation analysis, fixed-compression type and wet collagens were respectively associated with overcompression. On multivariate analysis, edematous collagen condition was the most important risk factor and proximal anvil side, fixed compression type, and overcompression were also independent risk factors for unacceptable compression injury. @*Conclusion@#In the edematous tissue condition, unintentional overcompression could be increased and result in tissue injury on the compression line of the circular stapler.
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PURPOSE: Colon perfusion status is one of the most important factors for the determination of postoperative anastomotic complications. Colonic hypoperfusion can be induced by inferior mesenteric artery (IMA) ligation in some patients. This study aimed to evaluate atherosclerotic risk assessment and vascular parameters of CT angiography as predictors of colonic hypoperfusion. METHODS: This prospective study was conducted at a tertiary referral hospital and included 46 rectosigmoid colon cancer patients undergoing laparoscopic anterior resection between August 2013 to July 2014. Atherosclerotic risk scores were assessed using the Framingham cardiovascular risk score system. The IMA length, branching pattern, atherosclerotic calcification, and intermesenteric artery and mesenteric vascular diameters were evaluated using CT angiography. Mesenteric marginal artery pressures were measured before and after IMA clamping. The mean arterial pressure (MAP) index was calculated by dividing the mesenteric marginal MAP into the systemic MAP to determine the mesenteric hypoperfusion status after IMA clamping. A critically low MAP index was defined as <0.4. RESULTS: Critically low MAP index (<0.4) was observed in 6 cases (13.0%) after IMA clamping. Atherosclerotic calcification of the IMA and superior mesenteric artery occurred in 11 (23.9%) and 5 patients (10.9%), respectively. Low MAP index was associated with high atherosclerotic risk score and short IMA length, rather than atherosclerotic calcification and other vascular parameters of the major mesenteric arteries. Multivariate analysis indicated that high atherosclerotic risk and short IMA length were independent predictors of critically low MAP index. CONCLUSION: Atherosclerotic risk assessment and IMA length were useful predictors of the mesenteric hypoperfusion status following IMA ligation during laparoscopic rectosigmoid colon surgery.
Subject(s)
Humans , Angiography , Arterial Pressure , Arteries , Atherosclerosis , Colon , Colonic Neoplasms , Constriction , Ligation , Mesenteric Arteries , Mesenteric Artery, Inferior , Mesenteric Artery, Superior , Multivariate Analysis , Perfusion , Prospective Studies , Risk Assessment , Tertiary Care CentersABSTRACT
The oncological outcomes of laparoscopic rectal cancer surgery were evaluated in recent multicenter randomized clinical trials (RCTs). The MRC-CLASSIC, COLOR II, and COREAN trials found no differences in local recurrence or disease-free survival rate between laparoscopic and open surgery. However, the noninferiority of laparoscopic surgery with respect to open surgery for rectal cancer was not established on statistical analysis in the ACOSOG Z6051 and the ALaCaRT trials. Quality of total mesorectal excision (TME) is one of the most important prognostic factors. Incomplete TME had unfavorable oncologic outcomes compared to complete TME. Although TME quality can be clearly identified on pathologic evaluation, there is controversy regarding the acceptable range of oncologically safe TME for laparoscopic surgery. It is not certain whether near-complete TME has an unfavorable oncologic impact and whether laparoscopic surgery with near-complete TME is an oncological threat. Therefore, the surgical community will be interested in the long-term outcomes and meta-analyses of ongoing large-scale RCTs. Laparoscopic rectal cancer surgery has been steadily improving its safety for oncology surgery, which has been reported consistently in various multicenter RCTs. To improve surgical quality, colorectal surgeons should choose the most appropriate surgical technique, including laparoscopic surgery.
Subject(s)
Disease-Free Survival , Laparoscopy , Quality Control , Rectal Neoplasms , Recurrence , Surgeons , Treatment OutcomeABSTRACT
PURPOSE: We evaluated the relationship of cancer-associated fibroblasts (CAFs) and desmoplastic reactions with cancer invasiveness and long-term outcomes in patients with colorectal cancer (CRC). METHODS: Histologic evaluation of mature CAFs and desmoplasia was performed by observing the collagen fiber structure and fibroblast cytomorphology in the intratumoral stroma and invasive front of CRC tissues. Cancer-cell invasiveness was evaluated using lymphatic invasion, vascular invasion, perineural invasion, tumor budding, and tumor growth patterns. Overall survival and systemic recurrence were analyzed. A network analysis was performed between CAF maturation, desmoplastic reaction, and cancer invasiveness. RESULTS: The proportions of mature CAFs in the intratumoral stroma and the invasive front were 57.6% and 60.3%, respectively. Epidermal growth factor receptor (EGFR) overexpression was significantly higher in the mature CAFs in the invasive front as compared to immature CAFs. Lymphatic invasion increased as the number of mature fibroblasts in the intratumoral stroma increased. Tumor budding was observed in almost half of both mature and immature stroma samples and occurred more frequently in infiltrating tumors. On network analysis, well-connected islands were identified that was associated with EGFR overexpression, CAF maturation, and infiltrating tumor growth patterns leading to tumor budding. CONCLUSION: The maturity of CAFs and desmoplastic reactions were associated with cancer invasion. However, the cytomorphologic characteristics of CAFs were insufficient as an independent prognostic factor for patients with CRC.