Practice parameters for early rectal cancer management: Italian Society of Colorectal Surgery (Società Italiana di Chirurgia Colo-Rettale; SICCR) guidelines

Value of 18F-FDG PET/CT in the diagnosis and grading of incidental colorectal adenomas

PURPOSE

Colorectal adenomas (CRAs) are at a higher risk of progressing to colorectal cancer (CRC) as their histological grade increases. Herein, this study investigated the relationship between the maximum standardized uptake value (SUVmax) on 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT) and the histological grades of CRAs and constructed the optimal regression model for distinguishing between different histological grades.

METHODS

This study retrospectively analyzed the data of 153 patients with CRAs who had colorectal 18F-FDG uptake incidentally found on PET/CT. The patients were categorized into low-grade intraepithelial neoplasia (LGIN) and high-grade intraepithelial neoplasia (HGIN) groups based on their histological grade. After the analysis of the relationship between SUVmax measured on preoperative 18F-FDG PET/CT scans and histological grades, receiver-operating characteristic (ROC) curves were analyzed to determine the optimal cut-off values for distinguishing between the two groups. Common clinical and pathological factors were included and subjected to univariate and multivariate logistic regression analyses to identify independent risk factors. A diagnostic model integrating SUVmax and several risk factors was developed with the multivariate logistic regression analysis.

RESULTS

SUVmax was significantly different between the two groups (P < 0.001) and increased with an elevation in the malignancy degree. The area under the ROC curve (AUC) for identifying LGIN and HGIN was 0.796, and the AUC of the combination model was 0.822. Furthermore, SUVmax was an independent risk factor for distinguishing between different histological grades in pairwise comparisons.

CONCLUSION

The regression model involving SUVmax on 18F-FDG PET/CT can distinguish between histological grades of CRAs, which therefore can be used as a noninvasive tool for the accurate diagnosis of CRAs and assist in developing patient-specific treatment strategies before surgery.

Minimally Invasive Rectal Surgery: Current Status and Future Perspectives in the Era of Digital Surgery

Over the past two decades, minimally invasive approaches in rectal surgery have changed the landscape of surgical interventions, impacting both malignant and benign pathologies. The dynamic nature of rectal cancer treatment owes much to innovations in surgical techniques, reflected in the expanding literature on available treatment modalities. Local excision, facilitated by minimally invasive surgery, offers curative potential for patients with early T1 rectal cancers and favorable pathologic features. For more complex cases, laparoscopic and robotic surgery have demonstrated significant efficacy and provided precise, durable outcomes while reducing perioperative morbidity and enhancing postoperative recovery. Additionally, advancements in imaging, surgical instrumentation, and enhanced recovery protocols have further optimized patient care. The integration of multidisciplinary care has also emerged as a cornerstone of treatment, emphasizing collaboration among surgeons, oncologists, and radiologists to deliver personalized, evidence-based care. This narrative review aims to elucidate current minimally invasive surgical techniques and approaches for rectal pathologies, spanning benign and malignant conditions, while also exploring future directions in the field, including the potential role of artificial intelligence and next-generation robotic platforms.

Local excision of T1 colorectal cancer: good differentiation, absence of lymphovascular invasion, and limited tumor radial infiltration (≤4.25 mm) may allow avoiding radical surgery

BACKGROUND

Early colorectal cancer (ECC) is defined as T1NXM0 colorectal cancer (CRC). Although a non-negligible number of T1-CRCs presents metastatic lymph-nodes, local excision is increasingly proposed as alternative to radical resection. Several criteria have been suggested to identify low-risk T1-CRC, but recommendations on this topic are still heterogeneous. This study aims to identify criteria associated with N+ T1-CRC, to select patients to undergo (or not) local excision.

METHODS

A retrospective analysis of demographic, clinical, and histology criteria of 122 consecutive T1-CRC patients undergoing radical resection at Parma University Hospital between 2000 and 2018 has been performed.

RESULTS

Lymph-node metastasis (LNM) was observed in 15/122 patients (12.3%). No LNM was observed among well-differentiated (G1) tumors (0/37), while 10/65 (15.4%) G2 cases as well as 5/20 (25%) G3 patients presented LNM. G1 was associated with absence of LNM (p = 0.013). After excluding G1 patients, the rate of N + T1-CRC was 17.6% (15/85). LNM was observed in 4/8 (50%) patients with lymphovascular invasion (LVI) and in 11/77 (14.2%) without LVI. LVI resulted being associated with LNM (p < 0.042). LNM was reported in 28.3% of cases with a tumor infiltration >4.25 mm (13/46), compared to 5.1% in cases with an infiltration ≤4.25 mm (2/39) (p = 0.012). In Cox regression analysis, the higher hazard ratio (HR) was reported for the LVI + and infiltration >4.25 mm (HR 24.849).

CONCLUSIONS

In patients with ECC (pT1NXM0), good differentiation (G1), absence of lymphovascular invasion (LVI-), and tumor radial infiltration ≤4.25 mm may allow performing local resection and avoiding radical surgery.

Is follow-up still mandatory more than 5 years after surgery for colorectal cancer?

PURPOSE

The aim of this study was to assess if to prolong follow-up (FU) more than 5 years after surgery for colorectal cancer (CRC) is justified or not.

METHODS

Patients who underwent surgery for a CRC before 2013 and without any tumor recurrence (or synchronous metastases) during the first 5 years after surgery were identified from our database and included.

RESULTS

Between 1996 and 2012, 121 patients operated for rectal (RC) (median of FU of 84 months; range 60-211) and 97 with colonic cancer (CC) (median of FU of 78 months; range 60-139), without any tumor recurrence (or synchronous metastases) during the first 5 years after surgery, presented a late tumor recurrence: 13/121 RC (10.7%) versus 2/97 CC (2.1%) (p = 0.014); 8/13 recurrences in RC (61.5%) were observed after neoadjuvant radiochemotherapy, and 9/13 (69.2%) in pN0 tumors. Among the 13 recurrences, 3 had both local and metastatic recurrences (23%), 5 an isolated local recurrence (38.5%) and 5 an isolated metastatic recurrence (38.5%). After surgery for CC, the 2 recurrences were observed in patients with T3N0 tumors.

CONCLUSION

After surgery for a CRC, in patients without tumor recurrence during the first 5 years after surgery, follow-up after 5 years must be continued in rectal cancer patients because of a 10.7% rate of late recurrence. On the opposite, after surgery for colon cancer the 2% rate of late recurrence after 5 years suggested that only patients with pT3-T4 colonic cancer could probably be followed more than 5 years after surgery.

Transanal Minimally Invasive Surgery

Transanal endoscopic surgery (TES) techniques encompass a variety of approaches, including transanal endoscopic microsurgery and transanal minimally invasive surgery. These allow a surgeon to perform local excision of rectal lesions with minimal morbidity and the potential to spare the need for proctectomy. As understanding of the long-term outcomes from these procedures has evolved, so have the indications for TES. In this study, we review the development of TES, its early results, and the evolution of new surgical techniques. In addition, we evaluate the most recent research on indications and outcomes in rectal cancer.

Long-term results of transanal endoscopic microsurgery after endoscopic polypectomy of malignant rectal adenoma

BACKGROUND

There is no consensus on the treatment and prognosis of malignant rectal polyps. The aim of the present study was to determine the role of transanal endoscopic microsurgery (TEM) after endoscopic complete polypectomy of malignant rectal adenomas with long-term follow-up.

METHODS

Of 105 patients with pT1 rectal carcinoma in 32 patients TEM followed complete endoscopic polypectomy while 73 had primary TEM. Local recurrence (LR), distant metastasis, overall and cancer-specific survival were determined by the Kaplan-Meier method.

RESULTS

Median follow-up was 9.1 years. In 32 patients with TEM following complete polypectomy no residual cancer was found. LR occurred in 3/28 (11%) patients with low-risk carcinoma (pT1 G1/2/X, L0/X, R0) and in 1/4 (25%) with high-risk carcinoma (pT1 G3/4 or L1). After primary TEM with complete resection (minimal distance >1 mm) LR occurred in 6/60 (10%) with low-risk carcinoma. After incomplete TEM resection (minimal distance ≤1 mm) LR occurred in 3/8 (38%) patients with low-risk and in 1/5 (20%) patients with high-risk carcinoma. Grading was the only significant risk factor for LR after endoscopic polypectomy followed by TEM (p = 0.002). At all outcomes did not differ between postpolypectomy TEM and primary TEM.

CONCLUSIONS

Patients with malignant rectal polyps removed by endoscopic polypectomy have a substantial risk of LR even if TEM of polyp site is cancer free. Risk of LR depends on tumor characteristics. In low-risk carcinoma long-term follow-up is necessary. The high LR rate in patients with high-risk rectal carcinoma restricts the use of TEM alone.

T1 colon cancer in the era of screening: risk factors and treatment

BACKGROUND

The aim of this study was to identify risk factors for lymph node positivity in T1 colon cancer and to carry out a surgical quality assurance audit.

METHODS

The sample consisted of consecutive patients treated for early-stage colon lesions in 15 colorectal referral centres between 2011 and 2014. The study investigated 38 factors grouped into four categories: demographic information, preoperative data, indications for surgery and post-operative data. A univariate and multivariate logistic regression analysis was performed to analyze the significance of each factor both in terms of lymph node (LN) harvesting and LN metastases.

RESULTS

Out of 507 patients enrolled, 394 patients were considered for analysis. Thirty-five (8.91%) patients had positive LN. Statistically significant differences related to total LN harvesting were found in relation to central vessel ligation and segmental resections. Cumulative distribution demonstrated that the rate of positive LN increased starting at 12 LN harvested and reached a plateau at 25 LN.

CONCLUSIONS

Some factors associated with an increase in detection of positive LN were identified. However, further studies are needed to identify more sensitive markers and avoid surgical overtreatment. There is a need to raise the minimum LN count and to use the LN count as an indicator of surgical quality.