Does a fine line exist between regional and metastatic pelvic lymph nodes in rectal cancer-striking discordance between national guidelines and treatment recommendations by US radiation oncologists.

Background: Management of rectal cancer with involved lateral pelvic lymph nodes (LPLNs) at the time of diagnosis-the stage we refer institutionally to as Stage 3.5-is controversial. The American Joint Committee on Cancer's 7 edition classifies internal iliac lymph nodes (LNs) as regional (Stage III), but both external and common iliac LNs as metastatic (Stage IV).

Preferential use of imaging modalities in staging newly diagnosed rectal cancer: a survey of US radiation oncologists.

Background: Accurate staging is crucial for management of patients with newly diagnosed rectal cancer. Endorectal ultrasound (EUS) has been the standard modality in the United States for decades, with magnetic resonance imaging (MRI) now preferred by national guidelines. Positron emission tomography (PET), conversely, is not recommended.