The impact of preoperative chemoradiotherapy on advanced low rectal cancer

XPF-ERCC1 Blocker Improves the Therapeutic Efficacy of 5-FU- and Oxaliplatin-Based Chemoradiotherapy in Colorectal Cancer

5-FU-based chemoradiotherapy (CRT) and oxaliplatin-based CRT are commonly used therapies for advanced colorectal cancer (CRC). However, patients with a high expression of ERCC1 have a worse prognosis than those with a low expression. In this study, we investigated the effect of XPF-ERCC1 blockers on chemotherapy and 5-FU-based CRT and oxaliplatin (OXA)-based CRT in colorectal cancer cell lines. We investigated the half-maximal inhibitory concentration (IC50) of 5-FU, OXA, XPF-ERCC1 blocker, and XPF-ERCC1 blocker, and 5-FU or OXA combined and analyzed the effect of XPF-ERCC1 blocker on 5-FU-based CRT and oxaliplatin-based CRT. Furthermore, the expression of XPF and γ-H2AX in colorectal cells was analyzed. In animal models, we combined the XPF-ERCC1 blocker with 5-FU and OXA to investigate the effects of RC and finally combined the XPF-ERCC1 blocker with 5-FU- and oxaliplatin-based CRT. In the IC50 analysis of each compound, the cytotoxicity of the XPF-ERCC1 blocker was lower than that of 5-FU and OXA. In addition, the XPF-ERCC1 blocker combined with 5-FU or OXA enhanced the cytotoxicity of the chemotherapy drugs in colorectal cells. Furthermore, the XPF-ERCC1 blocker also increased the cytotoxicity of 5-FU-based CRT and OXA -based CRT by inhibiting the XPF product DNA locus. In vivo, the XPF-ERCC1 blocker was confirmed to enhance the therapeutic efficacy of 5-FU, OXA, 5-FU-based CRT, and OXA CRT. These findings show that XPF-ERCC1 blockers not only increase the toxicity of chemotherapy drugs but also increase the efficacy of combined chemoradiotherapy. In the future, the XPF-ERCC1 blocker may be used to improve the efficacy of 5-FU- and oxaliplatin-based CRT.

The effect of Mitomycin-C in neoadjuvant concurrent chemoradiotherapy for rectal cancer

BACKGROUND

Neoadjuvant concurrent chemoradiotherapy (nCCRT) followed by total mesorectal excision has become the standard of care for advanced rectal cancer, but the most effective regimen of chemotherapeutic agents has not yet been determined. The purpose of this study is to determine the effect of Mitomycin-C (MMC) in nCCRT for rectal cancer.

METHODS

From 2000 to 2017, patients with rectal adenocarcinoma who received nCCRT followed by radical surgery were enrolled in our study. The patients were retrospectively separated into two groups according to nCCRT regimens (with or without MMC). Other factors related to cancer down-staging after nCCRT, disease-free survival (DFS) and overall survival (OS) were analyzed.

RESULTS

One hundred ninety-five patients received radiotherapy (RT) + MMC + oral tegafur-uracil (UFUR), and 191 patients received RT + UFUR without MMC as neoadjuvant CCRT. Adding MMC might increase the down-staging rate (odds ratio [OR] = 1.520, p = 0.058), and down-staging had significant effect to improve OS (OR = 1.726, p = 0.002) and DFS (OR = 2.185, p < 0.001). The OS and DFS were improved in patients who received MMC, although this result did not reach a statistically significant difference. There was a higher incidence of low-grade toxicities in the MMC group, especially neutropenia, genitourinary side effects, and dermatological side effects ( p < 0.001).

CONCLUSION

Adding MMC to the regimen of nCCRT for rectal adenocarcinoma is shown to increase tumor down-staging rate and improve disease-free and OS, although these benefits come at the cost of increased low-grade toxicities. Prospective randomized studies are needed to explore the role of MMC in nCCRT for rectal cancer.

Structured and shared MRI staging lexicon and report of rectal cancer: A consensus proposal by the French Radiology Group (GRERCAR) and Surgical Group (GRECCAR) for rectal cancer

PURPOSE

To develop French guidelines by experts to standardize data acquisition, image interpretation, and reporting in rectal cancer staging with magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Evidence-based data and opinions of experts of GRERCAR (Groupe de REcherche en Radiologie sur le CAncer du Rectum [i.e., Rectal Cancer Imaging Research Group]) and GRECCAR (Groupe de REcherche en Chirurgie sur le CAncer du Rectum [i.e., Rectal Cancer Surgery Research Group]) were combined using the RAND-UCLA Appropriateness Method to attain consensus guidelines. Experts scoring of reporting template and protocol for data acquisition were collected; responses were analyzed and classified as "Recommended" versus "Not recommended" (when ≥ 80% consensus among experts) or uncertain (when < 80% consensus among experts).

RESULTS

Consensus regarding patient preparation, MRI sequences, staging and reporting was attained using the RAND-UCLA Appropriateness Method. A consensus was reached for each reporting template item among the experts. Tailored MRI protocol and standardized report were proposed.

CONCLUSION

These consensus recommendations should be used as a guide for rectal cancer staging with MRI.

Effects of Neoadjuvant Radiotherapy on Postoperative Complications in Rectal Cancer: A Meta-Analysis

Objective

Neoadjuvant radiotherapy (nRT) is an important treatment approach for rectal cancer. The relationship, however, between nRT and postoperative complications is still controversial. Here, we conducted a meta-analysis to evaluate such concerns.

Methods

The electronic literature from 1983 to 2021 was searched in PubMed, Embase, and Web of Science. Postoperative complications after nRT were included in the meta-analysis. The pooled odds ratio (OR) was calculated by the random-effects model. Statistical analysis was conducted by Review Manager 5.3 and STATA 14.

Results

A total of 23,723 patients from 49 studies were included in the meta-analysis. The pooled results showed that nRT increased the risk of anastomotic leakage (AL) compared to upfront surgery (OR = 1.23; 95% CI, 1.07-1.41; p=0.004). Subgroup analysis suggested that both long-course (OR = 1.20, 95% CI 1.03-1.40; p=0.02) and short-course radiotherapy (OR = 1.25, 95% CI, 1.02-1.53; p=0.04) increased the incidence of AL. In addition, nRT was the main risk factor for wound infection and pelvic abscess. The pooled data in randomized controlled trials, however, indicated that nRT was not associated with AL (OR = 1.01; 95% CI 0.82-1.26; p=0.91).

Conclusions

nRT may increase the risk of AL, wound infection, and pelvic abscess compared to upfront surgery among patients with rectal cancer.

Efficacy of Neoadjuvant Therapy in Improving Long-Term Survival of Patients with Resectable Rectal Cancer: A Meta-Analysis

BACKGROUND

The impact of neoadjuvant therapy on long-term prognosis of patients with resectable rectal cancer is currently unknown.

OBJECTIVE

This study aimed to explore the long-term prognosis of patients with resectable rectal cancer following treatment with neoadjuvant therapy.

METHODS

Four major databases (PubMed, Web of Science, Embase, Cochrane library) were searched to identify relevant articles published between January 2000 and July 2020. The main outcome indicators were the 5-year overall survival (OS) and disease-free survival (DFS).

RESULTS

The meta-analysis revealed that 5-year OS (HR: 0.88, 95% Cl: 0.83-0.93) and DFS (HR: 0.95, 95% Cl: 0.91-0.98) were higher in patients with resectable rectal cancer after receiving neoadjuvant therapy than those treated with upfront surgery. Subgroup analysis demonstrated that the long-term survival of patients in Asia and Europe could benefit from neoadjuvant therapy. The neoadjuvant short-course radiotherapy (SCRT) and neoadjuvant chemo-radiotherapy (CRT) improved the 5-year OS and DFS of patients with stage Ⅱ-Ⅲ rectal cancer and mid/low rectal cancer. Further research found that patients with stage Ⅱ only had an increase in OS, while patients with stage Ⅲ have improved 5-year OS and DFS.

CONCLUSION

Neoadjuvant therapy improved the long-term survival of patients with mid/low rectal cancer in stage Ⅱ-Ⅲ (especially stage Ⅲ). Additionally, patients in Asia and Europe seemed to be more likely to benefit from neoadjuvant therapy. For the treatment, we recommend neoadjuvant SCRT and neoadjuvant CRT for resectable rectal cancer.

Staging of Locally Advanced Rectal Cancer Beyond TME

The management of rectal cancer is complex and continually evolving. With advancements in technology and the use of multidisciplinary teams to guide the treatment decision making, staging, oncologic, and functional outcomes are improving, and the management is moving toward personalized treatment strategies to optimize each individual patient's outcomes. Key in this evolution is imaging. Magnetic resonance imaging (MRI) has emerged as the dominant method of pelvic imaging in rectal cancer, and use of MRI for staging is best practice in multiple international guidelines. MRI allows a noninvasive assessment of the tumor site, relationship to surrounding structures, and provides highly accurate rectal cancer staging, which is necessary for determining the appropriate treatment strategy. However, the applications of MRI extend far beyond pretreatment staging. MRI can be used to predict outcomes in locally advanced rectal cancer and guide the surgical or nonsurgical plan, serving as a predictive and prognostic biomarker. With continued MRI hardware improvement and new sequence development, MRI may offer new perspectives in the assessment of treatment response and new innovations that could provide better insight into the staging, restaging, and outcomes with rectal cancer.

Rectal cancer MR staging: pearls and pitfalls at baseline examination

In recent years, rectal MRI has become a central diagnostic tool in rectal cancer staging. Indeed, rectal MR has the ability to accurately evaluate a number of important findings that may impact patient management, including distance of the tumor to the mesorectal fascia, presence of extramural vascular invasion (EMVI), presence of lymph nodes, and involvement of the peritoneum/anterior peritoneal reflection. Many of these findings are difficult to assess in nonexpert hands. In this review, we present a practical approach for radiologists to provide high-quality interpretations at initial baseline exams, based on recent guidelines from the Society of Abdominal Radiology, Rectal and Anal Cancer Disease Focused Panel. Practical pearls and pitfalls are discussed, focusing on optimization of technique including, patient preparation and protocol recommendations, interpretation, and essentials of reporting.

Effects of varying radiation dosages on MMP1 expression, and MMP1 knockdown on the viability and migration of SW620 cells

Colorectal cancer (CRC), also known as bowel cancer, is one of the leading causes of cancer-associated mortality worldwide at present. The aim of the present study was to detect the effects of matrix metalloproteinase 1 (MMP1) on the viability and migration of a CRC cell line in the presence or absence of variation X-ray radiation doses. The CRC cell line, SW620, was cultured and treated with different X-ray doses (0, 0.1, 0.5, 1, 3 and 6 Gy). MMP1 expression was downregulated via the application of a specific small interfering (si)-RNA. The viability and migration of SW620 cells prior to and following transfection were detected with MTT and Transwell chamber assays, respectively. The application of siRNA transfection to silence MMP1 in SW620 cells resulted in reduced cell viability and migration (P<0.05). Compared with the control, the cell viability and migration of cells were significantly reduced when exposed to 0.5, 1, 3, and 6 Gy X-ray radiation (P<0.05). In SW620 cells treated with different X-ray doses, the mRNA expression levels of MMP1 were significantly reduced (P<0.05). Cells treated with 0.5 Gy X-ray exposure exhibited the lowest mRNA expression levels of MMP1 when compared with other doses of X-ray radiation. The expression of MMP1 was associated with the promotion of the viability and migration of SW620 cells. X-ray radiation with 6 Gy dosages significantly reduced cell viability when compared with the control. Thus, MMP1-targeted therapy combined with radiotherapy could be used for treating CRC.

Comparative Outcomes of Preoperative Chemoradiotherapy and Selective Postoperative Chemoradiotherapy in Clinical Stage T3N0 Low and Mid Rectal Cancer

Purpose/aim: Preoperative chemoradiotherapy (pre-CRT) and total mesorectal excision (TME) have become the standard of care for patients with locally advanced rectal cancer (LARC). Nevertheless, it is a controversial issue whether pre-CRT in cT3N0M0 patients would result in potential overtreatment. Materials and methods: In total, 183 clinical stage IIA rectal cancer patients treated with and without pre-CRT between 2011 and 2014 were retrospectively analyzed. Capecitabine/FOLFOX/CAPOX chemotherapy was co-administered with preoperative radiotherapy. Surgical resection with laparoscopic or open TME was conducted 8-12 weeks after completion of the pre-CRT. Postoperative radiotherapy was routinely given to patients with pT4 lesion or circumferential margin (CRM) and/or distal resection margin (DRM) involvement. Results: In total, 108 (59%) patients received pre-CRT and 75 (41%) underwent surgery first. The pre-CRT patients presented with less-advanced pathological T stage tumors compared with the surgery-first patients (p < 0.001). However, the pathological N stage was not significantly different between the two groups (p = 0.065). The 3-year overall survival (OS), disease-free survival (DFS), and 2-year local recurrence (LR) rate were similar in the pre-CRT and surgery-first patients (88.4 versus 88.7%, p = 0.552; 79.6 versus 83.3%, p = 0.797; 2.8 versus 2.7%, p = 0.960, respectively). Cox regression analysis showed that pN stage and CRM/DRM involvement were independently correlated with an unfavorable DFS. Conclusions: In this study, the omission of pre-CRT in cT3N0M0 patients did not translate into a worse oncological outcome. Postoperative radiotherapy should remain a standard option for patients with CRM/DRM involvement and pathological T4 tumors. A generalized indication for pre-CRT in cT3N0 patients is likely to result in overtreatment.

Radiotherapy for stage IIA rectal cancer may not benefit all

This study sought to determine whether additional radiotherapy is necessary in patients after optimal surgery for stage IIA rectal cancer and how the different covariates influence the efficacy of radiotherapy. The first primary rectal cancer was identified from the 1988–December 2013 Surveillance, Epidemiology and End Results database. We identified 13647 patients with IIA rectal cancer, in which 39.6% received neo-adjuvant radiotherapy and in another 14.96% patients the adjuvant radiotherapy were performed. Neo-adjuvant or adjuvant radiotherapy group had better survival with 10-Year cancer-specific survival estimates as 75.1% and 73.8% compared to 68.4% of no radiotherapy group (P < 0.01). Adjusted hazard ratio (HR) demonstrated neo-adjuvant and adjuvant radiotherapy (HR: 0.814 and 0.848) were all associated with significantly decreased risk for cancer death. However, radiotherapy did not seem to yield the same survival benefit in selected population. Adjusted stratified analysis demonstrated patients with increasing age, relative large tumor size, and more retrieved regional lymph nodes had no additional benefit for cancer specific survival based on radiation use. In conclusions, unselected patients with stage IIA rectal cancer receiving radiotherapy experienced better survival in comparison to patients without radiation. However, additional radiotherapy is not beneficial for all.

Does neoadjuvant therapy increase the incidence of anastomotic leakage after anterior resection for mid and low rectal cancer? A systematic review and meta-analysis

AIM

The aim was to evaluate the association of neoadjuvant therapy with increases in the incidence of anastomotic leakage (AL) after middle and low rectal anterior resection.

METHOD

The electronic databases of PubMed, Web of Science, Scopus and Ovid were searched between 1980 and 2015. The random effects model was used to model the pooled data to determine the odds ratio with 95% confidence interval. Heterogeneity was evaluated using the Q test and I² statistics. Subgroup, sensitivity and meta-regression analysis was conducted to explore heterogeneity.

RESULTS

Neoadjuvant therapy was not shown to increase the incidence of postoperative AL as demonstrated by an OR of 1.16 [95% CI 0.99-1.36; P = 0.07 (random effects model)]. The subgroup analysis of neoadjuvant radiotherapy using the random effects model suggested that it did not increase the rate of postoperative AL (OR = 1.24, 95% CI 0.97-1.58; P = 0.08). The subgroup analysis of neoadjuvant chemoradiotherapy indicated that the rate of postoperative AL again did not increase with an OR = 1.06 [95% CI 0.86-1.30; P = 0.59 (random effects model)]. The interval to surgery after neoadjuvant therapy and preoperative radiotherapy (short or long course) was not associated with an increased incidence of postoperative AL.

CONCLUSION

Neoadjuvant therapy does not appear to increase the incidence of postoperative AL after anterior resection for mid and low rectal cancer. In addition, neither the interval to surgery after neoadjuvant therapy nor the radiotherapy regimen increases the rate of postoperative AL.

Local recurrence after curative resection for rectal carcinoma: The role of surgical resection

Local recurrence of rectal cancer is difficult to treat, may cause severe and disabling symptoms, and usually has a fatal outcome. The aim of this study was to document the clinical nature of locally recurrent rectal cancer and to determine the effect of surgical resection on long-term survival.A retrospective review was conducted of the prospectively collected medical records of 2485 patients with primary rectal adenocarcinoma who underwent radical resection between September 1994 and December 2008.In total, 147 (5.9%) patients exhibited local recurrence. The most common type of local recurrence was lateral recurrence, whereas anastomotic recurrence was the most common type in patients without preoperative concurrent chemoradiotherapy (CCRT). Tumor location with respect to the anal verge significantly affected the local recurrence rate (P < 0.001), whereas preoperative CCRT did not affect the local recurrence rate (P = 0.433). Predictive factors for surgical resection of recurrent rectal cancer included less advanced tumor stage (P = 0.017, RR = 3.840, 95% CI = 1.271-11.597), axial recurrence (P < 0.001, RR = 5.772, 95% CI = 2.281-14.609), and isolated local recurrence (P = 0.006, RR = 8.679, 95% CI = 1.846-40.815). Overall survival after diagnosis of local recurrence was negatively influenced by advanced pathologic tumor stage (P = 0.040, RR = 1.867, 95% CI = 1.028-3.389), positive CRM (P = 0.001, RR = 12.939, 95% CI = 2.906-57.604), combined distant metastases (P = 0.001, RR = 2.086, 95% CI = 1.352-3.218), and nonsurgical resection of recurrent tumor (P < 0.001, RR = 4.865, 95% CI = 2.586-9.153).In conclusion, the clinical outcomes of local recurrence after curative resection of rectal cancer are diverse. Surgical resection of locally recurrent rectal cancer should be considered as an initial treatment, especially in patients with less advanced tumors and axial recurrence.

The Value of Restaging With Chest and Abdominal CT/MRI Scan After Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer

Little was known with regard to the value of preoperative systemic restaging for patients with locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (CRT). This study was designed to evaluate the role of chest and abdominal computed tomography (CT) scan or magnetic resonance imaging (MRI) on preoperative restaging in LARC after neoadjuvant CRT and to assess the impact on treatment strategy.Between January 2007 and April 2013, 386 newly diagnosed consecutive patients with LARC who underwent neoadjuvant CRT and received restaging with chest and abdominal CT/MRI scan were included. Imaging results before and after CRT were analyzed.Twelve patients (3.1%) (6 liver lesions, 2 peritoneal lesions, 2 distant lymph node lesions, 1 lung lesions, 1 liver and lung lesions) were diagnosed as suspicious metastases on the restaging scan after radiotherapy. Seven patients (1.8%) were confirmed as metastases by pathology or long-term follow-up. The treatment strategy was changed in 5 of the 12 patients as a result of restaging CT/MRI findings. Another 10 patients (2.6%) who present with normal restaging imaging findings were diagnosed as metastases intra-operatively. The sensitivity, specificity accuracy, negative predictive value, and positive predictive values of restaging CT/MRI was 41.4%, 98.6%, 58.3%, and 97.3%, respectively.The low incidence of metastases and minimal consequences for the treatment plan question the clinical value of routine restaging of chest and abdomen after neoadjuvant CRT. Based on this study, a routine restaging CT/MRI of chest and abdomen in patients with rectal cancer after neoadjuvant CRT is not advocated, carcino-embryonic antigen (CEA) -guided CT/MRI restaging might be an alternative.

Oncologic Impact of Fewer Than 12 Lymph Nodes in Patients Who Underwent Neoadjuvant Chemoradiation Followed by Total Mesorectal Excision for Locally Advanced Rectal Cancer

A minimum of 12 harvested lymph nodes (hLNs) are recommended in colorectal cancer. However, a paucity of hLNs is frequently presented after preoperative chemoradiation (pCRT) in rectal cancer and the significance of this is still uncertain. The aim of this study is to analyze the impact of hLNs on long-term oncologic outcomes. A total of 302 patients with locally advanced rectal cancer who underwent pCRT and curative resection between 1989 and 2009 were reviewed. Patients were categorized into 2 groups according to the number of hLNs: <12 versus ≥12 LN. The 2 groups were compared with respect to 5-year disease-free and overall survival. The optimal number or ratio of hLNs was investigated in subgroup analysis according to LN status. The median follow-up was 57 months. Patient characteristics other than age did not differ between the 2 groups. The group with <12 LNs had more favorable ypTNM and ypN stage than those with ≥12 LNs. However, the long-term oncologic outcomes were not significantly different between the 2 groups. In subgroup analysis of ypN(-), the group with <5 hLNs had the most favorable oncologic outcomes. In ypN(+) cases, a higher LN ratio tended to be associated with poorer 5-year overall survival. The paucity of hLNs in locally advanced rectal cancer after chemoradiation did not imply poor oncologic outcomes in this study. In addition, <5 hLNs in ypN(-) patients could reflect a good tumor response rather than suboptimal radicality.

Selective use of adjuvant chemotherapy for rectal cancer patients with ypN0

BACKGROUND

The administration of adjuvant chemotherapy for rectal cancer patients with ypN0 is controversial. The purposes of this study were to evaluate the role of adjuvant chemotherapy in ypN0 patients and to optimize its use for these patients.

METHODS

We performed a retrospective study of 160 rectal cancer patients who had the final pathology of ypN0 between March 2003 and November 2010. Overall survival (OS), disease-free survival (DFS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) were compared between patients who did and did not receive adjuvant chemotherapy. Multivariate analysis was performed to explore clinical factors significantly associated with DFS, LRFS, and DMFS.

RESULTS

For ypT0-2N0 patients, the 5-year OS, DFS, LRFS, and DMFS were similar between patients who did and did not receive adjuvant chemotherapy (P > 0.05). For patients with ypT3-4N0, those who were given adjuvant chemotherapy exhibited a higher 5-year OS than those who were not (P = 0.026), with also an extended 5-year DFS (P = 0.050). Further analysis indicated that adjuvant chemotherapy could decrease the rates of distant metastases for ypT3-4N0 patients with no impact on local control. In multivariable analysis, both the final pathological stage and adjuvant chemotherapy were independent predictors of DMFS for the whole group. When stratified by pathological stage, adjuvant chemotherapy was still significantly associated with DMFS in the ypT3-4 stratum.

CONCLUSIONS

Adjuvant chemotherapy may not improve survival for ypT0-2N0 patients. However, it may be clinically meaningful for ypT3-4N0 patients by decreasing rates of distant metastases. Further randomized controlled clinical trials are needed to address this problem.

Preoperative versus postoperative chemoradiotherapy in stage T3, N0 rectal cancer

BACKGROUND

The study populations of previous preoperative chemoradiotherapy (pre-CRT) studies have consisted of mixed clinical stages, such as cT3-cT4 and/or cN positive. For this reason, it has not been possible to demonstrate whether pre-CRT is of benefit for individual subgroups.

METHODS

The medical records of 137 rectal cancer patients with clinical stage T3, N0 disease who received either pre-CRT or postoperative chemoradiotherapy (post-CRT) between 2002 and 2011 were retrospectively analyzed. The regimen of pre-CRT consisted of slow fluorouracil (5FU) infusion and that of post-CRT consisted of bolus 5FU and leucovorin concurrent with radiation.

RESULTS

Following pre-CRT, significant downstaging was achieved. However, administration of pre-CRT did not influence the type of surgical resection in tumours ≤5 cm distant from the anal verge (p = 0.14). Pathological complete response was achieved in 16 % of the patients in the pre-CRT group. The local recurrence rate (LRR) at 5 years was 5.7 % in the pre-CRT and 11.1 % in the post-CRT groups (p = 0.04). The distant recurrence rate (DRR) at 5 years was 76 % and 77 % in the pre-CRT and post-CRT groups, respectively (p = 0.1). Overall survival was similar in two groups (74.8 % vs. 75.3 %, p = 0.3).

CONCLUSIONS

The treatment of stage T3, N0 rectal cancer patients with pre-CRT followed by surgery decreased LRR, but did not improve DRR or OS as compared with surgery followed by post-CRT in our patient cohort.

The use of MR imaging in treatment planning for patients with rectal carcinoma: have you checked the "DISTANCE"?

Rectal cancer is a common and serious disease in the Western hemisphere. Optimal treatment of rectal cancer involves a multidisciplinary approach, with collaboration required between radiologists, oncologists, surgeons, and pathologists to achieve local control and decrease the rate of recurrence. Several studies have been published that show the ability to accurately stage rectal cancer with magnetic resonance (MR) imaging. Moreover, advances in preoperative therapies require accurate preoperative staging with MR imaging to select those patients who may benefit from more intensive treatment, without subjecting those who will not benefit to unnecessary treatment. As we enter an era of individualized patient care, stratified according to the risk of both local and distant failure, imaging takes on the same importance as the tumor type and genetic susceptibility. MR imaging is now an essential tool to enable the oncology team to make appropriate treatment decisions. However, rectal cancer evaluation with MR imaging remains a challenge in the hands of nonexperts. This article describes a mnemonic device, "DISTANCE," to enable a systematic approach to the interpretation of MR images, thereby enabling all the clinically relevant features to be adequately assessed: DIS, for Distance from the Inferior part of the tumor to the transitional Skin; T, for T staging; A, for Anal complex; N, for Nodal staging; C, for Circumferential resection margin; and E, for Extramural vascular invasion.

Carcinoembryonic antigen (CEA) level, CEA ratio, and treatment outcome of rectal cancer patients receiving pre-operative chemoradiation and surgery

Background

To investigate serum carcinoembryonic antigen (CEA) as a prognostic factor for rectal cancer patients receiving pre-operative chemoradiotherapy (CRT).

Methods

Between 2000 and 2009, 138 patients with advanced rectal cancer receiving CRT before surgery at our hospital were retrospectively classified into 3 groups: pre-CRT CEA <6 ng/ml (group L; n = 87); pre-CRT CEA ≥ 6 ng/ml and post-CRT CEA <6 ng/ml (group H-L; n = 32); and both pre- and post-CRT CEA ≥ 6 ng/ml (group H-H; n = 19). CEA ratio (defined as post-CRT CEA divided by pre-CRT CEA), post-CRT CEA level and other factors were reviewed for prediction of pathologic complete response (pCR).

Results

Five-year disease-free survival (DFS) was better in groups L (69.0%) and H-L (74.5%) than in group H-H (44.9%) (p = 0.024). Pathologic complete response was observed in 19.5%, 21.9% and 5.3% of groups L, H-L and H-H respectively (p = 0.281). Multivariate analysis showed that ypN stage and pCR were independent prognostic factors for DFS and that post-CRT CEA level was independently predictive of pCR. As a whole, post-CRT CEA <2.61 ng/ml predicted pCR (sensitivity 76.0%; specificity 58.4%). For those with pre-CRT CEA ≥6 ng/ml, post-CRT CEA and CEA ratio both predicted pCR (sensitivity 87.5%, specificity 76.7%).

Conclusions

In patients with pre-CRT serum CEA ≥6 ng/ml, those with “normalized” CEA levels after CRT may have similar DFS to those with “normal” (<6 ng/ml) pre-CRT values. Post-CRT CEA level is a predictor for pCR, especially in those with pre-CRT CEA ≥6 ng/ml.

Tumor scatter after neoadjuvant therapy for rectal cancer: are we dealing with an invisible margin?

BACKGROUND

After the impressive response of rectal cancers to neoadjuvant therapy, it seems reasonable to ask: can we can excise the small ulcer locally or avoid a radical resection if there is no gross residual tumor? Does gross response reflect what happens to tumor cells microscopically after radiation?

OBJECTIVE

The aim of this study was to identify microscopic tumor cell response to radiation.

DESIGN

This study is a retrospective review of a prospectively collected database.

SETTING

This investigation was conducted at a single tertiary medical center.

PATIENTS

Patients were selected who had elective radical resection for rectal cancer after preoperative chemotherapy and radiation performed by 2 colorectal surgeons between 2006 and 2011.

MAIN OUTCOME MEASURES

The primary outcome measured was tumor presence after radiation therapy

RESULTS

Of the 75 patients, 20 patients were complete responders and 55 had residual cancer. Of these patients, 28 had no tumor cells seen outside the gross ulcer, and 27 (49.1%) had tumor outside the visible ulcer or microscopic tumor present with no overlying ulcer. Of these tumors, 81.5% were skewed away from the ulcer center. The mean distance of distal scatter was 1.0 cm from the visible ulcer edge to a maximum of 3 cm; 3 patients had tumor cells more than 2 cm distal to the visible ulcer edge. Tumor scatter outside the ulcer was not associated with poor prognostic factors, such as nodal and distant disease, perineural invasion, or mucin; however, it was associated with lymphovascular invasion (χ2 = 4.12, p = 0.038)

LIMITATIONS

There was limited access to clinical information gathered outside our institution.

CONCLUSIONS

Our study suggests that 1) after radiation, the gross ulcer cannot be used to determine the sole area of potential residual tumor, 2) cancer cells may be found up to 3 cm distally from the gross ulcer, so the traditional 2-cm margin may not be adequate, and 3) local excision of the ulcer or no excision after apparent complete response appears to be insufficient treatment for rectal cancer.

Preoperative concurrent chemoradiotherapy for locally advanced rectal cancer: treatment outcomes and analysis of prognostic factors

PURPOSE

This study was designed to investigate the long-term oncologic outcomes for locally advanced rectal cancer patients after treatment with preoperative concurrent chemoradiotherapy followed by total mesorectal excision, and to identify prognostic factors that affect survival and pathologic response.

MATERIALS AND METHODS

From June 1996 to June 2009, 135 patients with locally advanced rectal cancer were treated with preoperative concurrent chemoradiotherapy followed by total mesorectal excision at Kyung Hee University Hospital. Patient data was retrospectively collected and analyzed in order to determine the treatment outcomes and identify prognostic factors for survival.

RESULTS

The median follow-up time was 50 months (range, 4.5 to 157.8 months). After preoperative chemoradiotherapy, sphincter preservation surgery was accomplished in 67.4% of whole patients. A complete pathologic response was achieved in 16% of patients. The estimated 5- and 8-year overall survival, loco-regional recurrence-free survival, and distant metastasis-free survival rate for all patients was 82.7% and 75.7%, 76.8% and 71.9%, 67.9% and 63.3%, respectively. The estimated 5- and 8-year overall survival, loco-regional recurrence-free survival, and distant metastasis-free survival rate for pathologic complete responders was 100% and 100%, 100% and 88.9%, 95.5% and 95.5%, respectively. In the multivariate analysis, pathologic complete response was significantly associated with overall survival. The predictive factor for pathologic complete response was pretreatment clinical stage.

CONCLUSION

Preoperative chemoradiotherapy for locally advanced rectal cancer resulted in a high rate of overall survival, sphincter preservation, down-staging, and pathologic complete response. The patients achieving pathologic complete response had very favorable outcomes. Pathologic complete response was a significant prognostic factor for overall survival and the significant predictive factor for a pathologic complete response was pretreatment clinical stage.

Potential contribution of preoperative neoadjuvant concurrent chemoradiation therapy on margin-negative resection in borderline resectable pancreatic cancer

BACKGROUND

Margin-negative pancreatectomy provides only chance to cure pancreatic cancer. However, borderline resectable pancreatic cancer (BRPCa) has the risk of incomplete palliative resection.

MATERIALS AND METHODS

We retrospectively reviewed 32 patients with BRPCa who underwent a pancreatectomy following preoperative chemoradiation therapy (CCRT (+)/Px group) and compared these patients with those with resectable pancreatic cancer (RPCa) who underwent pancreatectomy without preoperative CCRT (CCRT (-)/Px group, n=104).

RESULTS

Eighteen patients (56.2%) showed more than 50% significant pathological response to CCRT. The degree of pathological responses showed a positive relationship between final pT stage (p=0.075). More frequent vascular resection (p<0.001), transfusion (p=0.076), and longer operation time were observed in the CCRT(+)/Px group. However, similar R0 resection rates (p=0.272), lower pT stage (p<0.001), smaller number of metastastic lymph nodes (p=0.002), and lower incidence of lymph node metastasis (p=0.032) were noted in the CCRT(+)/Px group. The overall disease-specific survival were similar (median survival, 30.5 months (95% CI; 23.6-37.4) vs. 26.3 months (95% CI; 15.9-36.7), p=0.709), and no statistical differences in cancer recurrence risks were noted between the two groups (p=0.505).

CONCLUSION

Pancreatectomy following preoperative neoadjuvant CCRT can be a potential strategy for margin-negative resection in BRPCa patients.