Adjuvant Radiotherapy in Incidental Positive Nodal Disease in Rectal Cancer-A Systemic Review.

Area of Science:

• Oncology
• Surgical Oncology
• Gastrointestinal Oncology

Background:

• Optimal adjuvant treatment for incidentally detected node-positive rectal cancer post-surgery is unclear.
• Preoperative chemoradiotherapy (CRT) is standard for advanced rectal cancer, but adjuvant radiotherapy (RT) role in early stage node-positive disease is debated.
• This review assesses survival outcomes and prognostic factors for different adjuvant treatments.

Purpose of the Study:

• To evaluate survival outcomes of adjuvant treatment modalities for incidental node-positive rectal cancer.
• To identify prognostic factors influencing disease progression in this patient group.
• To inform optimal adjuvant treatment strategies following curative surgery.

Main Methods:

• Systematic literature search of PubMed, EMBASE, MEDLINE, and Cochrane Library up to August 2024.
• Included retrospective studies of rectal cancer patients with incidental nodal disease undergoing curative surgery without neoadjuvant therapy.
• Risk of bias assessed using Newcastle-Ottawa Scale; meta-analysis not performed due to heterogeneity.

Main Results:

• Nine studies (5989 patients) analyzed; adjuvant therapy improved outcomes versus observation.
• Overall survival (OS) varied: 61.3%-92% (chemotherapy), 63%-93% (CRT), 42%-82.1% (no adjuvant therapy).
• Local recurrence lowest with CRT (2%-9.1%); poorer outcomes linked to pN2 disease, positive margins, perineural invasion, high lymph node ratio, and low tumor location.

Conclusions:

• Adjuvant chemotherapy (CT) enhances survival in incidental node-positive rectal cancer.
• Radiotherapy (RT) may benefit high-risk subgroups within this population.
• Further prospective studies are essential to confirm findings and refine treatment guidelines.