Trends and outcome of neoadjuvant treatment for rectal cancer: A retrospective analysis and critical assessment of a 10-year prospective national registry on behalf of the Spanish Rectal Cancer Project

Short-term surgical outcomes of rectal adenocarcinoma surgical treatment in Latin America: a multicenter, retrospective assessment in 49 centers from 12 countries

INTRODUCTION

Rectal cancer is a prevalent disease that requires multidisciplinary management. Results of treatment of patients suffering from this malignancy in Latin America have been scarcely reported before.

METHODS

A retrospective, multicenter study was conducted to report preoperative and operative characteristics of patients intervened for rectal cancer in centers from Latin America during 2015-2022, and the short-term results of treatment were analyzed. The study was open to any center receiving rectal cancer patients, irrespective of volume. The main study outcome was 30-day postoperative complications including any deviation from the normal postoperative course (Clavien Dindo I to V).

RESULTS

A total of 2044 patients from 49 centers in 12 Latin American countries were included, with a mean age of 63 years. Twenty-five percent of patients were operated in low-volume centers. Twenty-nine percent of patients had a tumor located in the low rectum, and only 53% of patients had preoperative MRI for local staging. A total of 1052 patients (52%) received neoadjuvant therapy before surgery. Eighty-six percent of patients were operated by a specialized colorectal surgeon, and 31% of patients were intervened using a conventional approach. A total of 29.9% of patients presented a postoperative complication. The anastomotic leak rate was 8.9%. Fifty-eight percent of pathology reports had less than 12 lymph nodes harvested, and 22.9% of reports did not include mesorectal quality. In the multivariate analysis, neoadjuvant therapy (OR: 1.44, p-value: 0.023), urgent procedures (OR: 3.73, p-value: 0.049), intraoperative complications (OR: 2.21, p-value: 0.046), advanced tumors (OR: 1.39, p-value: 0.036), and prolonged surgery (OR: 1.74, p-value: 0.004) were found to be independently related to suffering postoperative complications.

CONCLUSIONS

This study includes information about the approach and results of rectal cancer management in Latin America at a large scale. In the future, this information can be used as a bridge to identify areas of improvement among rectal cancer patients' treatment in the region.

Effect and imaging analysis of cetuximab combined with radiotherapy in patients with rectal carcinoma

OBJECTIVE

To analyze the effect of cetuximab combined with radiotherapy in patients with rectal carcinoma (RC) by imaging analysis.

METHODS

The clinical data of 104 RC patients at our hospital from February 2021 to February 2022 were retrospectively analyzed. They were separated into control group (n = 52) and experimental group (n = 52) according to the order of admission, with the former treated with radiotherapy alone and the latter receiving cetuximab and radiotherapy. The clinical efficacy, tumor marker levels and imaging parameters of different treatment regimens were compared, and Quality of Life questionnaire (QLQ-C30) was used to evaluate the quality of life.

RESULTS

The incidence of tumor regression grade (TRG) downgrade, T stage downgrade and N stage downgrade was remarkably higher in the experimental group than in the control group (P < 0.05). The experimental group had remarkably lower tumor marker levels (P < 0.001) and higher mean score of EORTC Core QLQ-C30 (P < 0.001) than those in the control group. The relative signal intensity of tumor (SIT/M), relative signal intensity reduction rate of tumor (SIT/MRR) and apparent diffusion coefficient (ADC) values were remarkably higher (P < 0.001) and the absolute signal intensity of tumor (SIT) value was remarkably lower (P < 0.001) in the experimental group than the control group.

CONCLUSION

Treatment with cetuximab and radiotherapy can greatly reduce serum tumor marker levels in RC patients and bring them health benefits, and further studies will help establish a better solution for such patients.

Preoperative Radiotherapy Decision-Tree for Rectal Cancer Patients: A Real-World Analysis Based on the Swedish Colorectal Cancer Registry

BACKGROUND

There are 3 widely used preoperative radiotherapy (RT) procedures in rectal cancer treatment including long-course RT (LRT), short-course RT with delayed surgery (SRTW), and short-course RT with immediate surgery (SRT). However, further evidence is required to determine which treatment option results in more optimal patient survival.

METHODS

This Swedish Colorectal Cancer Registry-based retrospective study of real-world data included 7766 stage I-III rectal cancer patients, of which 2982, 1089, 763, and 2932 patients received no RT (NRT), LRT, SRTW, and SRT, respectively. The Kaplan-Meier survival curve and Cox proportional hazard multivariate model were used to identify potential risk factors and to examine the independent association of RT with patient survival after adjusting for baseline confounding factors.

RESULTS

RT effects on survival differed by age and clinical T stage (cT) subgroups. Subsequent survival analysis by age and cT subgroups confirmed that patients ≥70 years old with cT4 benefited from any RT (P < .001, NRT as reference) and equally from any RT (P > .05 pairwise between RTs). In contrast, for cT3 patients ≥70 years, SRT and LRT were associated with better survival than SRTW (P < .001). In patients <70 years, LRT and SRTW had superior survival benefits in cT4 patients but inferior to SRT (P < .001); SRT was the only effective treatment in the cT3N+ subgroup (P = .032); patients with cT3N0 and <70 years did not benefit from any RT.

CONCLUSION

This study suggests that preoperative RT strategies may have varying effects on the survival of rectal cancer patients, depending on their age and clinical stage.

Starting a national, prospective colorectal cancer registry in a developing country: how to do it, potential limitations and results of a pilot study

AIM

Prospective registries of patients operated on for malignancies at a national scale are not common in developing countries. The aim of this work is to report the process of creation of a prospective national colorectal cancer registry in a middle-income country in Latin America and the main results of a pilot study involving eight centres.

METHOD

The project involved the creation of a national database including all patients operated on for colorectal cancer in Argentina and a 30-year plan to make improvements based on the information provided by the registry. The first phase comprised the prospective registration of all patients treated in eight tertiary referral centres during a 6-month period.

RESULTS

Three hundred and seventeen patients were prospectively recruited during the study period, and 244 (77%) were operated on for colon cancer. The completion rate for all variables was >95%. The median age for the group was 66.88 years. Right-sided colon tumours were the most frequent. Colorectal specialists performed 257 (81.07%) of the procedures, and in 273 (87.22%) patients a laparoscopic approach was used with an overall conversion rate of 12.45%. Major complication and anastomotic leakage rates for the group were 18.55% and 8.81%, respectively. The mortality rate was 1.94%. Multivariate analysis showed that young patients and operations performed by general surgeons were the most common factors independently related to worse postoperative outcomes. Note that this manuscript describes an early phase of the project that included only eight tertiary referral centres.

CONCLUSION

Despite its limitations, this study describes the effort made to generate reliable data on which to base future decisions to improve patient care. Furthermore, it might set an example for other developing countries to start their own registries.

Patient and multidisciplinary team perspectives on watch and wait in rectal cancer

This article adopts a multidisciplinary approach, including surgery, oncology, radiology and patient perspectives, to discuss the key points of debate surrounding a watch and wait approach. In an era of shared decision-making, discussion of watch and wait as an option in the context of complete clinical response is appropriate, although it is not the gold standard treatment. Key challenges are the difficulty in assessing for a complete clinical response, prediction of recurrence and access to timely diagnostics for surveillance. Salvage surgery has good results if regrowth is detected early but does have imperfect outcomes, with only a 90% salvage rate. Good communication with patients about the risks and alternatives is essential. Patients undergoing watch and wait should ideally be enrolled in prospective registries or clinical trials.

Toxicities and outcomes of neoadjuvant treatment in elderly patients with locally advanced rectal cancer: a scoping review protocol

INTRODUCTION

Colorectal cancer remains the second leading cause of cancer-related death in 60-79 years old and the third leading cause of death in patients aged 80 and above. Rectal cancer accounts for approximately a third of colorectal cancer diagnoses. The current standard of care for managing locally advanced rectal cancer involves a multimodal combined approach with neoadjuvant treatment, surgery with total mesorectal excision and adjuvant chemotherapy. Neoadjuvant treatment can be in the form of short-course radiotherapy, long-course concurrent radiotherapy with chemotherapy or total neoadjuvant chemotherapy with concurrent chemoradiotherapy followed by chemotherapy. This scoping aims to assess the toxicity and outcome of the different neoadjuvant treatment modalities in elderly patients.

METHODS AND ANALYSIS

We will use Arksey and O'Malley's five scoping review methodology framework stages. Searches will be conducted in Ovid Medline, Embase, Cochrane database and CINAHL. In addition, the researcher will hand search for all registered trials, using a combination of terms such as "locally advanced rectal cancer", "neoadjuvant treatment", and "elderly patients." Two independent reviewers will screen titles and abstracts and then full text based on predefined inclusion and exclusion criteria. Publications will be extracted using a customised data extraction tool to include study characteristics, research topics, exposures and outcomes.

ETHICS AND DISSEMINATION

Ethics approval is not required as the data will be collected from the existing literature. The findings of this study will help with future clinical research on the topic. We will publish the findings of this review in a peer-reviewed journal and present them at academic conferences targeting geriatric oncology service providers.

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.

Is Metformin Associated With Improved Response to Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer?

Efforts to determine whether metformin can increase the effectiveness of neoadjuvant chemoradiotherapy in rectal cancer have increased in recent years. However, retrospective studies have yielded inconclusive results.

OBJECTIVES

The aim of this study was to compare oncological outcomes and survival after neoadjuvant chemoradiotherapy in patients with rectal cancer taking metformin versus in those not taking metformin.

METHODS

This study analyzed 423 consecutive patients with locally advanced rectal cancer who underwent neoadjuvant chemoradiotherapy and curative surgery between January 2010 and May 2020; of these, 59 were taking metformin and 364 were not taking metformin.

RESULTS

Patients taking metformin had a lower proportion of tumor regression (6.8% versus 22.0%, P = 0.012) as well as a lower proportion of patients achieving a pathological complete response (6.8% versus 20.6%, P = 0.011). In the multivariate analysis, independent predictors of pathologic complete response were not taking metformin (OR: 5.26, 95% CI: 1.12-24.85, P= 0.035) and cT2 stage (OR: 3.49, 95% CI: 1.10-11.07, P= 0.034); the interval was also an independent predictor of tumor regression (OR: 1.78, 95% CI: 1.06-2.96, P= 0.028). No differences were observed in survival between groups.

CONCLUSION

Metformin was not associated with better tumor responses or survival after neoadjuvant treatment.

Endorectal Ultrasound and Magnetic Resonance Imaging for Rectal Cancer Staging: A Modern Multimodality Approach

Preoperative staging represents a crucial point for the management, type of surgery, and candidacy for neoadjuvant therapy in patient with rectal cancer. The most recent clinical guidelines in oncology recommend an accurate preoperative evaluation in order to address early and advanced tumors to different therapeutic options. In particular, potential pitfalls may occur in the assessment of T3 tumors, which represents the most common stage at diagnosis. The depth of tumor invasion is known to be an important prognostic factor in rectal carcinoma; as a consequence, the T3 imaging classification has a substantial importance for treatment strategy and patient survival. However, the differentiation between tumor invasion of perirectal fat and mesorectal desmoplastic reactions remains a main goal for radiologists. Magnetic resonance imaging (MRI) is actually considered as the best imaging modality for rectal cancer staging. Although the endorectal ultrasound (ERUS) is the preferred staging method for early tumors, it could also be useful in identifying perirectal fat invasion. Moreover, the addiction of diffusion weighted imaging (DWI) improves the diagnostic performance of MRI in rectal cancer staging by adding functional information about rectal tumor and adjacent mesorectal tissues. This study investigated the diagnostic performance of conventional MRI alone, in combination with the DWI technique and ERUS in order to assess the best diagnostic imaging combination for rectal cancer staging.

Neoadjuvant Chemotherapy in Locally Advanced Rectal Cancer

Most clinical practice guidelines recommend a selective approach for rectal cancer after clinical staging. In low-risk patients, upfront surgery may be an appropriate option. However, in patients with MRI-defined high-risk features such as extramural vascular invasion, multiple nodal involvement or T4 and/or tumors close to or invading the mesorectal fascia, a more intensive preoperative approach is recommended, which may include neoadjuvant or preoperative chemotherapy. The potential benefits include better compliance than postoperative chemotherapy, a higher pathological complete remission rate, which facilitates a non-surgical approach, and earlier treatment of micrometastatic disease with improved disease-free survival compared to standard preoperative chemoradiation or short-course radiation. Two recently reported phase III randomized trials, RAPIDO and PRODIGE 23, show that adding neoadjuvant chemotherapy to either standard short-course radiation or standard long-course chemoradiation in locally advanced rectal cancer patients reduces the risk of metastasis and significantly prolongs disease-related treatment failure and disease-free survival. This review discusses these potentially practice-changing trials and how they may affect our current understanding of treating locally advanced rectal cancers.