Local Recurrence Of Rectal Cancer Research Articles

Proton beam reirradiation for locally recurrent rectal cancer patients with prior pelvic irradiation.

The aim of the present study was to report the feasibility of proton beam reirradiation for patients with locally recurrent rectal cancer (LRRC) with prior pelvic irradiation. The study population included patients who were treated with proton beam therapy (PBT) for LRRC between 2008 and December 2019 in our institution. Those who had a history of distant metastases of LRRC, with or without treatment, before reirradiation, were excluded. Overall survival (OS), progression-free survival (PFS) and local control (LC) were estimated using the Kaplan-Meier method. Ten patients were included in the present study. The median follow-up period was 28.7months, and the median total dose of prior radiotherapy (RT) was 50Gy (range, 30Gy-74.8Gy). The median time from prior RT to reirradiation was 31.5months (range, 8.1-96.6months), and the median reirradiation dose was 72Gy (relative biological effectiveness) (range, 56-77Gy). The 1-year/2-year OS, PFS and LC rates were 100%/60.0%, 20.0%/10.0% and 70.0%/58.3%, respectively, with a median survival time of 26.0months. Seven patients developed a Grade 1 acute radiation dermatitis, and no Grade≥2 acute toxicity was recorded. Grade≥3 late toxicity was recorded in only one patient, who had developed a colostomy due to radiation-related intestinal bleeding. Reirradiation using PBT for LRRC patients who had previously undergone pelvic irradiation was feasible. However, the indications for PBT reirradiation for LRRC patients need to be considered carefully due to the risk of severe late GI toxicity.

Extraperitoneal lateral pelvic sidewall excision: a novel rectal-sparing approach for lateral locally recurrent rectal cancer.

Locally recurrent rectal cancer (LRRC) involving the lateral pelvic sidewall requires a complex approach to maximize the likelihood of R0 resection, which is the only predictor of survival. The purpose of this report is to describe a novel technique to resect a localized lateral pelvic sidewall LRRC. A 63-year-old male patient was referred for a 15-mm LRRC near the right internal iliac vessels. Endoscopic ultrasound and magnetic resonance imaging excluded any involvement of the pelvic colon or residual rectum. A combined extraperitoneal antero-lateral approach and gluteal access were used to optimize vascular control on the internal iliac vessels, to promptly identify the ureter and to achieve a better posterior exposition of the sciatic notch. This technique allowed a controlled and tailored resection of pelvic sidewall without entering into the abdominal cavity. The postoperative course was uneventful. The pathologic report confirmed clear margins (R0), with one involving obturator lymph node. At 3months, the patient is alive and free from local re-relapse. A right lung metastasis has occurred, and it was treated by stereotactic radiotherapy. The present report proposes a novel extraperitoneal pelvic sidewall excision to resect lateral LRRC with a colorectal-sparing approach, thus minimizing the risk of exenterative surgery-related complications. A proper selection of patients is mandatory, as the proposed technique could not be generalized as the standard of care in all lateral LRRCs.

Evolution of clinical nature, treatment and survival of locally recurrent rectal cancer: Comparative analysis of two national cross-sectional cohorts

BackgroundIn the Netherlands, use of neoadjuvant radiotherapy for rectal cancer declined after guideline revision in 2014. This decline is thought to affect the clinical nature and treatability of locally recurrent rectal cancer (LRRC). Therefore, this study compared two national cross-sectional cohorts before and after the guideline revision with the aim to determine the changes in treatment and survival of LRRC patients over time. MethodsPatients who underwent resection of primary rectal cancer in 2011 (n = 2094) and 2016 (n = 2855) from two nationwide cohorts with a 4-year follow up were included. Main outcomes included time to LRRC, synchronous metastases at time of LRRC diagnosis, intention of treatment and 2-year overall survival after LRRC. ResultsUse of neoadjuvant (chemo)radiotherapy for the primary tumour decreased from 88.5% to 60.0% from 2011 to 2016. The 3-year LRRC rate was not significantly different with 5.1% in 2011 (n = 114, median time to LRRC 16 months) and 6.3% in 2016 (n = 202, median time to LRRC 16 months). Synchronous metastasis rate did not significantly differ (27.2% vs 33.7%, p = 0.257). Treatment intent of the LRRC shifted towards more curative treatment (30.4% vs. 47.0%, p = 0.009). In the curatively treated group, two-year overall survival after LRRC diagnoses increased from 47.5% to 78.7% (p = 0.013). ConclusionPrimary rectal cancer patients in 2016 were treated less often with neoadjuvant (chemo)radiotherapy, while LRRC rates remained similar. Those who developed LRRC were more often candidate for curative intent treatment compared to the 2011 cohort, and survival after curative intent treatment also improved substantially.

Factors associated with one-year mortality after curative surgery for primary clinical T4 and locally recurrent rectal cancer in elderly patients

IntroductionDespite advancements in colorectal cancer care, one-year post-operative mortality rates remain high for elderly patients who have undergone curative surgery for primary clinical T4 rectal cancer (cT4RC) or locally recurrent rectal cancer (LRRC). This study aimed to identify factors associated with one-year mortality and to evaluate the causes of death. Materials & methodsThis retrospective cohort study included patients aged ≥70 years who underwent surgery with curative intent for cT4RC or LRRC between January 2013 and December 2020. Clinical and follow-up data were collected and analyzed to determine survival rates and investigate factors associated with mortality within one year after surgery. ResultsA total of 183 patients (94 cT4RC, 89 LRRC) were included. One-year mortality rates were 16.0% for cT4RC and 28.1% for LRRC (P = 0.064). In cT4RC patients, factors associated with one-year mortality were preoperative anemia (OR 3.83, P = 0.032), total pelvic exenteration (TPE) (OR 7.18, P = 0.018), multivisceral resections (OR 5.73, P = 0.028), pulmonary complications (OR 13.31, P < 0.001) and Clavien-Dindo grade ≥ III complications (OR 5.19, P = 0.025). In LRRC patients, factors associated with one-year mortality were TPE (OR 27.00, P = 0.008), the need for supported care after discharge (OR 3.93, P = 0.041) and Clavien-Dindo grade ≥ III complications (OR 3.95, P = 0.006). The main causes of death in cT4RC and LRRC patients were failure to recover (cT4RC 26.6%, LRRC 28.0%) and disease recurrence (cT4RC 26.6%, LRRC 60.0%). ConclusionIn order to tailor treatment in elderly with cT4RC and LRRC, factors associated with increased one-year mortality (e.g. pre-operative anemia, TPE) should be incorporated in the decision-making process. Clinical trial registrationNot applicable.

A follow-up study on monitoring local recurrence of rectal cancer after surgery by endoscopic ultrasound

A follow-up study on monitoring local recurrence of rectal cancer after surgery by endoscopic ultrasound

Value of Size and Malignant Features of Lateral Lymph Nodes in Risk Stratification at Lateral Local Recurrence of Rectal Cancer: A National Cohort Study.

Patients with rectal cancer who have enlarged lateral lymph nodes (LLNs) have an increased risk of lateral local recurrence (LLR). However, little is known about prognostic implications of malignant features (internal heterogeneity, irregular margins, loss of fatty hilum, and round shape) on MRI and number of enlarged LLNs, in addition to LLN size. Of the 3,057 patients with rectal cancer included in this national, retrospective, cross-sectional cohort study, 284 with a cT3-4 tumor located ≤8 cm from the anorectal junction who received neoadjuvant treatment and who had visible LLNs on MRI were selected. Imaging was reassessed by trained radiologists. LLNs were categorized based on size. Influence of malignant features and the number of LLNs on LLR was investigated. Of 284 patients with at least 1 visible LLN, 122 (43%) had an enlarged node (≥7.0 mm) and 157 (55%) had malignant features. Of the 122 patients with enlarged nodes, 25 had multiple (≥2). In patients with a single enlarged node (n=97), a single malignant feature was associated with a 4-year LLR rate of 0% and multiple malignant features was associated with a rate of 17% (P=.060). In the group with multiple malignant features, their disappearance on restaging was associated with an LLR rate of 13% compared with an LLR rate of 20% for persistent malignant features (P=.532). The presence of intermediate-size LLNs (5.0-6.9 mm) with at least 1 malignant feature was associated with a 4-year LLR rate of 8%; the 4-year LLR rate was 13% when the malignant features persisted on restaging MRI (P=.409). Patients with multiple enlarged LLNs had a 4-year LLR rate of 28% compared with 11% for those with a single enlarged LLN (P=.059). The presence of multiple enlarged LLNs (≥7.0 mm), as well as multiple malignant features in an enlarged node contribute to the risk of developing an LLR. These radiologic features can be used for clinical decision-making regarding the potential benefit of LLN dissection.

Local Recurrence of Rectal Cancer After Transanal Total Mesorectal Excision and Risk Factors: A Nationwide Multicenter Cohort Study in Japan

Objective: To investigate the oncological outcomes after transanal total mesorectal excision (TaTME) for rectal cancer and risk factors for local recurrence (LR). Background: A high LR rate with a multifocal pattern early after TaTME has been reported in Norway and the Netherlands, causing controversy over the oncological safety of this technique. Methods: Twenty-six member institutions of the Japan Society of Laparoscopic Colorectal Surgery participated in this retrospective cohort study. A total of 706 patients with primary rectal cancer who underwent TaTME between January 2012 and December 2019 were included for analysis. The primary endpoint was the cumulative 3-year LR rate. Results: A total of 253 patients had clinical stage III disease (35.8%) and 91 (12.9%) had stage IV. Intersphincteric resection was performed in 318 patients (45.0%) and abdominoperineal resection in 193 (27.3%). There was 1 urethral injury (0.1%). A positive resection margin (R1) was seen in 42 patients (5.9%). Median follow-up was 3.42 years, and the 2- and 3-year cumulative LR rates were 4.95% (95% confidence interval: 3.50–6.75) and 6.82% (95% confidence interval: 5.08–8.89), respectively. A multifocal pattern was observed in 14 (25%) of 56 patients with LR. Tumor height from the anal verge, pathological T4 disease, pathological stage III/IV, positive perineural invasion, and R1 resection were significant risk factors for LR in multivariable analysis. Conclusions: In this selected cohort in which intersphincteric resection or abdominoperineal resection was performed in more than half of cases, oncological outcomes were acceptable during a median follow-up of more than 3 years.

Influence of colorectal anastomotic leakage on time before the loop stoma closing

Background. Important task is determining the long-term consequences of colorectal anastomotic leakage. Leakage with clinical manifestations leads to a higher frequency of local recurrences of rectal cancer and increases the severity of manifestations of low anterior resection syndrome. How does the leakage of colorectal anastomosis affect the period before the closure of loop stoma?Aim. To determine the influence of anastomotic leakage on the term before closing the ileostomy.Methods. In this retrospective incomparable study were included 618 patients with rectal cancer who had been underwent anterior or low anterior resection with formation colorectal anastomosis and loop stoma.Results. Colorectal anastomotic leakage was detected in 86 from 618 patients (13.9 %). The loop stoma was closed in 513 from 618 (83 %) patients. The time to the preventive stoma closure in patients with anastomotic leakage was significantly higher than in patients without anastomotic leakage, p = 0.001. Reconstructive surgery in patients without anastomotic leakage was performed in 9 months after anterior resection. The median time before the stoma closure of patients with X – ray anastomosis leakage was 11 months, with clinical leakage – 17 months, p &lt;0.001.Conclusion. Colorectal anastomotic leakage statistically increases the term before ileostomy closure.

Beyond Total Mesorectal Excision (TME)-Results of MRI-Guided Multivisceral Resections in T4 Rectal Carcinoma and Local Recurrence.

Rectal cancer invading adjacent organs (T4) and locally recurrent rectal cancer (LRRC) pose a special challenge for surgical resection. We investigate the diagnostic performance of MRI and the results that can be achieved with MRI-guided surgery. All consecutive patients who underwent MRI-based multivisceral resection for T4 rectal adenocarcinoma or LRRC between 2005 and 2019 were included. Pelvic MRI findings were reviewed according to a seven-compartment staging system and correlated with histopathology. Outcomes were investigated by comparing T4 tumors and LRRC with respect to cause-specific survival in uni- and multivariate analysis. We identified 48 patients with T4 tumors and 28 patients with LRRC. Overall, 529 compartments were assessed with an accuracy of 81.7%, a sensitivity of 88.6%, and a specificity of 79.2%. Understaging was as low as 3.0%, whereas overstaging was 15.3%. The median number of resected compartments was 3 (interquartile range 3-4) for T4 tumors and 4 (interquartile range 3-5) for LRRC (p = 0.017). In 93.8% of patients with T4 tumors, a histopathologically complete (R0(local)-) resection could be achieved compared to 57.1% in LRRC (p < 0.001). Five-year overall survival for patients with T4 tumors was 53.3% vs. 32.1% for LRRC (p = 0.085). R0-resection and M0-category emerged as independent prognostic factors, whereas the number of resected compartments was not associated with prognosis in multivariate analysis. MRI predicts compartment involvement with high accuracy and especially avoids understaging. Surgery based on MRI yields excellent loco-regional results for T4 tumors and good results for LRRC. The number of resected compartments is not independently associated with prognosis, but R0-resection remains the crucial surgical factor.

High Level Sacral Bone Resection for Locally Recurrent Rectal Cancer.

Locally recurrent rectal cancer (LRRC) involving the upper sacrum is generally considered a contraindication for curative surgery. In the surgical management of LRRC, sacrectomy is frequently performed to secure clear resection margins. Nonetheless, the indications for high sacrectomy remain controversial due to potential postoperative complications, questions about radicality, and the increased complexity of the operation. Furthermore, comprehensive studies addressing this issue are notably absent. This study aimed to assess the feasibility, safety, and surgical prognosis in high sacrectomy for LRRC. All patients with LRRC who required concomitant sacrectomy, but did not include the inferior margin of the second sacral vertebra, between 2003 and 2014, were reviewed retrospectively. Eight patients with a median age of 59 years were included in this study. The proximal resection line for sacral bone resection was the central part of the S1 vertebra in one patient, lower edge of the S1 vertebra in six patients, and central part of the S2 vertebra in one patient. Negative margin resection was achieved in five out of the eight patients. The median operative time was 922 min, and the median operative blood loss volume was 6,370 ml. Major complications included pelvic abscess (n=5), ileus (n=1), and pulmonary vein embolism (n=1), none of which proved fatal during the postoperative period. Both the 5-year local re-recurrence-free survival rate and the 5-year distant metastasis-free survival rate were 50% (4/8). High sacrectomy is safe and feasible to achieve negative margins in patients with LRRC.

Local Recurrence in Rectal Cancer: Small Absolute Numbers in a BIG Problem.

Local Recurrence in Rectal Cancer: Small Absolute Numbers in a BIG Problem.

Modern Techniques in Re-Irradiation for Locally Recurrent Rectal Cancer: A Systematic Review.

Radiotherapy (RT) plays an important role in the treatment of patients with previously irradiated locally recurrent rectal cancer (LRRC). Over the years, numerous technologies and different types of RT have emerged. The aim of our systematic literature review was to determine whether the new techniques have led to improvements in both outcomes and toxicities. A computerized search was performed by MEDLINE and the Cochrane database. The studies reported data from patients treated with carbon ion radiotherapy (CIRT), intensity-modulated photon radiotherapy (IMRT), and stereotactic radiotherapy (SBRT). Seven publications of the 126 titles/abstracts that emerged from our search met the inclusion criteria and presented outcomes of 230 patients. OS was reported with rates of 90.0% and 73.0% at 1 and 2 years, respectively; LC was 89.0% and 71.6% at 1 and 2 years after re-RT, respectively. Toxicity data vary widely, with emphasis on acute and chronic gastrointestinal and urogenital toxicity, even with modern techniques. data on toxicity and outcomes of re-RT for LRRC with new technologies are promising compared with 3D techniques. Comparative studies are needed to define the best technique, also in relation to the site of recurrence.

Definitive carbon ion re-irradiation with pencil beam scanning in the treatment of unresectable locally recurrent rectal cancer.

This study aimed to evaluate the oncological outcomes and safety of carbon ion re-irradiation with pencil beam scanning (PBS) delivery technique for previously irradiated and unresectable locally recurrent rectal cancer (LRRC). Between June 2017 and September 2021, 24 patients of unresectable LRRC with prior pelvic photon radiotherapy who underwent carbon ion re-irradiation at our institute were retrospectively analyzed. Carbon ion radiotherapy was delivered by raster scanning with a median relative biological effectiveness-weighted dose of 72Gy in 20 fractions. Weekly CT reviews were carried out, and offline adaptive replanning was performed whenever required. The median follow-up duration was 23.8months (range, 6.2-47.1months). At the last follow-up, two patients had a local disease progression, and 11 patients developed distant metastases. The 1- and 2-year local control, progression-free survival and overall survival rates were 100 and 93.3%, 70.8 and 45.0% and 86.7 and 81.3%, respectively. There were no Grade 3 or higher acute toxicities observed. Three patients developed Grade 3 late toxicities, one each with gastrointestinal toxicity, skin reaction and pelvic infection. In conclusion, definitive carbon ion re-irradiation with PBS provided superior oncologic results with tolerable toxicities and may be served as a curative treatment strategy in unresectable LRRC.

Implementation of an Enhanced Recovery after Surgery Protocol in Advanced and Recurrent Rectal Cancer Patients after beyond Total Mesorectal Excision Surgery: A Feasibility Study.

The implementation of an Enhanced Recovery After Surgery (ERAS) protocol in patients with locally advanced rectal cancer (LARC) and locally recurrent rectal cancer (LRRC) has been deemed unfeasible until now because of the heterogeneity of this disease and low caseloads. Since evidence and experience with ERAS principles in colorectal cancer care are increasing, a modified ERAS protocol for this specific group has been developed. The aim of this study is to evaluate the implementation of a tailored ERAS protocol for patients with LARC or LRRC, requiring beyond total mesorectal excision (bTME) surgery. Patients who underwent a bTME for LARC or LRRC between October 2021 and December 2022 were prospectively studied. All patients were treated in accordance with the ERAS LARRC protocol, which consisted of 39 ERAS care elements specifically developed for patients with LARC and LRRC. One of the most important adaptations of this protocol was the anaesthesia procedure, which involved the use of total intravenous anaesthesia with intravenous (iv) lidocaine, iv methadone, and iv ketamine instead of epidural anaesthesia. The outcomes showed compliance with ERAS care elements, complications, length of stay, and functional recovery. A follow-up was performed at 30 and 90 days post-surgery. Seventy-two patients were selected, all of whom underwent bTME for either LARC (54.2%) or LRRC (45.8%). Total compliance with the adjusted ERAS protocol was 73.6%. Major complications were present in 12 patients (16.7%), and the median length of hospital stay was 9 days (IQR 6.0-14.0). Patients who received multimodal anaesthesia (75.0%) stayed in the hospital for a median of 7.0 days (IQR 6.8-15.5). These patients received fewer opioids on the first three postoperative days than patients who received epidural analgesia (p < 0.001). The implementation of the ERAS LARRC protocol seemed successful according to its compliance rate of >70%. Its complication rate was substantially reduced in comparison with the literature. Multimodal anaesthesia is feasible in beyond TME surgery with promising effects on recovery after surgery.

Redo Pelvic Surgery and Combined Metastectomy for Locally Recurrent Rectal Cancer with Known Oligometastatic Disease: A Multicentre Review.

Historically, surgical resection for patients with locally recurrent rectal cancer (LRRC) had been reserved for those without metastatic disease. 'Selective' patients with limited oligometastatic disease (OMD) (involving the liver and/or lung) are now increasingly being considered for resection, with favourable five-year survival rates. A retrospective analysis of consecutive patients undergoing multi-visceral pelvic resection of LRRC with their oligometastatic disease between 1 January 2015 and 31 August 2021 across four centres worldwide was performed. The data collected included disease characteristics, neoadjuvant therapy details, perioperative and oncological outcomes. Fourteen participants with a mean age of 59 years were included. There was a female preponderance (n = 9). Nine patients had liver metastases, four had lung metastases and one had both lung and liver disease. The mean number of metastatic tumours was 1.5 +/- 0.85. R0 margins were obtained in 71.4% (n = 10) and 100% (n = 14) of pelvic exenteration and oligometastatic disease surgeries, respectively. Mean lymph node yield was 11.6 +/- 6.9 nodes, with positive nodes being found in 28.6% (n = 4) of cases. A single major morbidity was reported, with no perioperative deaths. At follow-up, the median disease-free survival and overall survival were 12.3 months (IQR 4.5-17.5 months) and 25.9 months (IQR 6.2-39.7 months), respectively. Performing radical multi-visceral surgery for LRRC and distant oligometastatic disease appears to be feasible in appropriately selected patients that underwent good perioperative counselling.

Utility of circulating tumour DNA for prognosis and prediction of therapeutic effect in locally recurrent rectal cancer: study protocol for a multi-institutional, prospective observational study (JCOG1801A1, CAP-LR study)

IntroductionIn locally recurrent rectal cancer (LRRC), surgery is a standard treatment for resectable disease. However, short-term and long-term outcomes are unsatisfactory due to the invasive nature of surgical procedures and...

Pathological determinants of outcome following resection of locally advanced or locally recurrent rectal cancer

IntroductionPathological factors that influence and predict survival following pelvic exenteration (PE) for locally advanced (LARC) or locally recurrent rectal cancer (LRRC), especially LRRC, remain poorly understood. A clear resection margin has previously been demonstrated to be of most significance. Materials and methodsA retrospective cohort study was performed for all patients undergoing a curative PE for LARC or LRRC between 2008 and 2021 at a tertiary referral UK specialist colorectal hospital. Cox regression analysis was planned to identify pathological factors associated with overall (OS), disease free (DFS) and local recurrence free survival (LRFS). Results388 patients were included in the analysis with 256 resections for LARC and 132 for LRRC. 62.4% of patients were male with a median age of 59 years (IQR 49–67). 247 (64%) partial pelvic exenterations and 141 (36%) total pelvic exenterations performed. Overall R0 rate 86.6%. Poorly differentiated tumours and a positive resection margin independently influenced OS, DFS and LRFS on multivariate analysis in LARC. On multivariate analysis venous invasion negatively influenced DFS and poorly differentiated lesions negatively influenced LRFS in LRRC. ConclusionsA positive resection margin and poorly differentiated tumours are significant negative prognostic markers for survival and recurrence in LARC. The results of this study support the need to look for alternative prognostic markers beyond that in the existing standard reporting dataset for rectal cancers. With increasing R0 rates, novel prognostic pathological markers are required to help guide treatment and surveillance for patients with LRRC.

Pattern of care for re-irradiation in locally recurrent rectal cancer: a national survey on behalf of the AIRO gastrointestinal tumors study group

PurposeRadical resection (R0) represents the best curative treatment for local recurrence (LR) rectal cancer. Re-irradiation (re-RT) can increase the rate of R0 resection. Currently, there is a lack of guidelines on Re-RT for LR rectal cancer. The Italian Association of Radiation and clinical oncology for gastrointestinal tumors (AIRO-GI) study group released a national survey to investigate the current clinical practice of external beam radiation therapy in these patients.Material and methodsIn February 2021, the survey was designed and distributed to members of the GI working group. The questionnaire consisted of 40 questions regarding center characteristics, clinical indications, doses, and treatment techniques of re-RT for LR rectal cancer.ResultsA total of 37 questionnaires were collected. Re-RT was reported as an option for neoadjuvant treatment in resectable and unresectable disease by 55% and 75% of respondents, respectively. Long-course treatment with 30–40 Gy (1.8–2 Gy/die, 1.2 Gy bid) and hypofractionated regimen of 30–35 Gy in 5 fractions were used in most centers. A total dose of 90–100 Gy as EqD2 dose (α/β = 5 Gy) was delivered by 46% of the respondents considering the previous treatment. Modern conformal techniques and daily image-guided radiation therapy protocols were used in 94% of centers.ConclusionOur survey showed that re-RT treatment is performed with advanced technology that allow a good management of LR rectal cancer. Significant variations were observed in terms of dose and fractionation, highlighting the need for a consensus on a common treatment strategy that could be validated in prospective studies.

Local Recurrences in Rectal Cancer: MRI vs. CT

Rectal cancers are often considered a distinct disease from colon cancers as their survival and management are different. Particularly, the risk for local recurrence (LR) is greater than in colon cancer. There are many factors predisposing to LR such as postoperative histopathological features or the mesorectal plane of surgical resection. In addition, the pattern of LR in rectal cancer has a prognostic significance and an important role in the choice of operative approach and. Therefore, an optimal follow up based on imaging is critical in rectal cancer. The aim of this review is to analyse the risk and the pattern of local recurrences in rectal cancer and to provide an overview of the role of imaging in early detection of LRs. We performed a literature review of studies published on Web of Science and MEDLINE up to January 2023. We also reviewed the current guidelines of National Comprehensive Cancer Network (NCCN) and the European Society for Medical Oncology (ESMO). Although the timing and the modality of follow-up is not yet established, the guidelines usually recommend a time frame of 5 years post surgical resection of the rectum. Computed Tomography (CT) scans and/or Magnetic Resonance Imaging (MRI) are the main imaging techniques recommended in the follow-up of these patients. PET-CT is not recommended by guidelines during post-operative surveillance and it is generally used for problem solving.

Construction and validation of a prognostic nomogram for locally recurrent rectal cancer: a population-based study.

Postoperative recurrence was a life-threatening condition for patients with rectal cancer. Due to the heterogeneity of locally recurrent rectal cancer (LRRC) and controversy of the optimal treatment for patients, it was difficult to predict the prognosis of LRRC. This study aimed to develop and validate a nomogram that could accurately predict the survival probability of LRRC. Patients diagnosed with LRRC between 2004 and 2019 from the Surveillance, Epidemiology, and End Results (SEER) database were included in the analysis. Multiple imputations with chained equations were used for missing values. These patients were further randomized into training set and testing set. Cox regression was used for univariate and multivariate analysis. Potential predictors were screened by the least absolute shrinkage and selection operator (LASSO). The Cox hazards regression model was constructed and it was visualized by nomogram. C-index, calibration curve, and decision curve were used to evaluate the model's predictive ability. Then X-tile was used to calculate the optimal cut-off values for all patients and the cohort was divided into three groups. A total of 744 LRRC patients were enrolled and allocated to the training set (n=503) and the testing set (n=241). Cox regression analysis of the training set yielded meaningfully clinicopathological variables. A survival nomogram was created based on the identification of ten clinicopathological features in the LASSO regression analyses of the training set. The C-index of 3-, 5-year survival probabilities were 0.756, 0.747 in training set, and 0.719, 0.726 in testing set, respectively. The calibration curve and decision curve both demonstrated the satisfactory performance of the nomogram for prognosis prediction. Moreover, the prognosis of LRRC could be well distinguished according to the grouping of risk scores (P<0.001 in three groups). This nomogram was the first prediction model to preliminarily evaluate the survival of LRRC patients, which could provide more accurate and efficient treatment in clinical practice.