[Predicting pN positivity in T3 rectal cancer].

Area of Science:

• Oncology
• Surgical Pathology
• Gastrointestinal Oncology

Background:

• Accurate staging of T3 rectal cancer is crucial for treatment strategy, with lymph node (pN+) status being a key determinant.
• Preoperative imaging sensitivity for detecting lymph node metastasis in rectal cancer is suboptimal.
• Identifying reliable preoperative predictors for pT3pN+ stage in rectal cancer is essential.

Purpose of the Study:

• To analyze predictive factors associated with lymph node involvement (pN+) in patients with T3 rectal cancer.
• To identify preoperative indicators that correlate with positive lymph node status in rectal cancer.

Main Methods:

• Retrospective analysis of 89 patients who underwent rectal resection for (y)pT3 rectal cancer between 2011 and 2014.
• Data collected prospectively included patient demographics, tumor characteristics (location, grading, invasion), treatment history, and lymph node status.
• Statistical analysis was performed to identify risk factors for pN+ disease.

Main Results:

• Lymph node positivity (pN+) was observed in 57.3% of the studied T3 rectal cancer patients.
• Significant risk factors for pN+ rectal cancer included lymphovascular invasion (p<0.001), angioinvasion (p=0.030), and perineural invasion (p=0.010).
• Low tumor grading showed a borderline association with pN+ status (p=0.084), while tumor penetration depth was not significant (p=0.230).

Conclusions:

• The study confirms that lymph node positivity in T3 rectal cancer is associated with lymphovascular invasion, perineural invasion, and low tumor grade.
• These identified factors are critical for understanding rectal cancer progression and metastasis.
• Despite the identified associations, accurate preoperative identification of these predictive factors for rectal cancer remains a clinical challenge.