Surveillance strategies following curative resection and non-operative approach of rectal cancer: How and how long? Review of current recommendations

Risk factors, monitoring, and treatment strategies for early recurrence after rectal cancer surgery

Early recurrence (ER) following surgery for rectal cancer is a significant factor impacting patient survival rates. Tsai et al identified age, preoperative neoadjuvant therapy, length of hospital stay, tumour location, and pathological stage as factors influencing the risk of ER. Postoperative monitoring for ER should encompass a thorough medical history review, physical examination, tumour marker testing, and imaging studies. Additionally, noninvasive circulating tumour cell DNA testing can be utilized to predict ER. Treatment strategies may involve radical surgery, radiation therapy, chemotherapy, and immunotherapy. Through a comprehensive analysis of risk factors, the optimization of monitoring methods, and the development of personalized treatment strategies, it is anticipated that both the efficacy of treatment and the quality of life for rectal cancer patients with postoperative recurrence can be significantly improved.

Identifying timing and risk factors for early recurrence of resectable rectal cancer: A single center retrospective study

BACKGROUND

Colorectal cancer is a common malignancy and various methods have been introduced to decrease the possibility of recurrence. Early recurrence (ER) is related to worse prognosis. To date, few observational studies have reported on the analysis of rectal cancer. Hence, we reported on the timing and risk factors for the ER of resectable rectal cancer at our institute.

AIM

To analyze a cohort of patients with local and/or distant recurrence following the radical resection of the primary tumor.

METHODS

Data were retrospectively collected from the institutional database from March 2011 to January 2021. Clinicopathological data at diagnosis, perioperative and postoperative data, and first recurrence were collected and analyzed. ER was defined via receiver operating characteristic curve. Prognostic factors were evaluated using the Kaplan-Meier method and Cox proportional hazards modeling.

RESULTS

We included 131 patients. The optimal cut off value of recurrence-free survival (RFS) to differentiate between ER (n = 55, 41.9%) and late recurrence (LR) (n = 76, 58.1%) was 8 mo. The median post-recurrence survival (PRS) of ER and LR was 1.4 mo and 2.9 mo, respectively (P = 0.008) but PRS was not strongly associated with RFS (R² = 0.04). Risk factors included age ≥ 70 years [hazard ratio (HR) = 1.752, P = 0.047], preoperative concurrent chemoradiotherapy (HR = 3.683, P < 0.001), colostomy creation (HR = 2.221, P = 0.036), and length of stay > 9 d (HR = 0.441, P = 0.006).

CONCLUSION

RFS of 8 mo was the optimal cut-off value. Although ER was not associated with PRS, it was still related to prognosis; thus, intense surveillance is recommended.

Non-operative management of rectal cancer: Highlighting the controversies

There remains much ambiguity on what non-operative management (NOM) of rectal cancer truly entails in terms of the methods to be adopted and the best algorithm to follow. This is clearly shown by the discordance between various national and international guidelines on NOM of rectal cancer. The main aim of the NOM strategy is organ preservation and avoiding unnecessary surgical intervention, which carries its own risk of morbidity. A highly specific and sensitive surveillance program must be devised to avoid patients undergoing unnecessary surgical interventions. In many studies, NOM, often interchangeably called the Watch and Wait strategy, has been shown as a promising treatment option when undertaken in the appropriate patient population, where a clinical complete response is achieved. However, there are no clear guidelines on patient selection for NOM along with the optimal method of surveillance.

Current Applications and Future Directions of Circulating Tumor Cells in Colorectal Cancer Recurrence

The ability to predict or detect colorectal cancer (CRC) recurrence early after surgery enables physicians to apply appropriate treatment plans and different follow-up strategies to improve patient survival. Overall, 30-50% of CRC patients experience cancer recurrence after radical surgery, but current surveillance tools have limitations in the precise and early detection of cancer recurrence. Circulating tumor cells (CTCs) are cancer cells that detach from the primary tumor and enter the bloodstream. These can provide real-time information on disease status. CTCs might become novel markers for predicting CRC recurrence and, more importantly, for making decisions about additional adjuvant chemotherapy. In this review, the clinical application of CTCs as a therapeutic marker for stage II CRC is described. It then discusses the utility of CTCs for monitoring cancer recurrence in advanced rectal cancer patients who undergo neoadjuvant chemoradiotherapy. Finally, it discusses the roles of CTC subtypes and CTCs combined with clinicopathological factors in establishing a multimarker model for predicting CRC recurrence.

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.