Metabolic and magnetic resonance imaging: complementary modalities for the preoperative assessment of lateral pelvic lymph nodes in rectal cancer.

BACKGROUND: The management of lateral pelvic lymph nodes for rectal cancer is a topical and controversial issue. The aim of this study was to assess the relationship between lateral pelvic lymph node features on magnetic resonance imaging (MRI) and positron emission tomography-computed tomography (PET-CT) with oncological outcomes in patients with rectal cancer. METHODS: A retrospective analysis of 284 patients with primary locally advanced rectal cancer treated with neoadjuvant therapy and surgical resection with curative intent between January 2003 and Dec 2018 was undertaken. From this study population, a select cohort of 77 patients with abnormal lateral pelvic lymph nodes on preoperative imaging had imaging re-analysed by radiologists blinded to clinical outcomes. Pre and post neoadjuvant therapy MRI and PET-CT lateral pelvic lymph node features were correlated with oncological outcomes. RESULTS: A lateral pelvic lymph node short axis size ≥5 mm on post neoadjuvant therapy MRI was a significant predictor of worse 3-year local recurrence free survival (HR 8.35, P = 0.001). Lateral pelvic lymph node avidity on post neoadjuvant therapy PET-CT was a significant predictor of worse 3-year distant recurrence free survival (HR 5.62, P = 0.001). No correlation of oncological outcomes with overall survival was identified. CONCLUSION: Lateral pelvic lymph node imaging features on post-neoadjuvant therapy MRI and PET-CT predicted those at risk of rectal cancer recurrence. Further studies are required to confirm these findings that suggest restaging MRI and PET-CT are complementary modalities for the preoperative assessment of lateral pelvic lymph nodes in rectal cancer.

Functional outcomes after lateral pelvic lymph node dissection for rectal cancer: a systematic review and meta-analysis.

PURPOSE: Lateral pelvic lymph node dissection (LPLND) may improve oncological outcomes for select patients with rectal cancer, though functional outcomes may be adversely impacted. The aim of this study is to assess the functional outcomes associated with LPLND for rectal cancer and compare these outcomes with standard surgical resection. METHODS: A systematic search was undertaken to identify relevant studies reporting on urinary dysfunction (UD), sexual dysfunction (SD), and defecatory dysfunction (DD) for patients who underwent LPLND for rectal cancer. Studies comparing functional outcomes in patients who underwent surgery with and without LPLND were assessed. In addition, a comparison of functional outcomes in patients who underwent LPLND before and after the year 2000 was performed. RESULTS: Twenty-one studies of predominantly non-randomised observational data were included. Ten were comparative studies. Male SD was worse in patients who underwent LPLND compared with those who did not (RR 1.68 (95% CI 1.41-1.99, P < 0.001)). No difference was observed for the rate of UD between treatment groups. The rates of UD and male SD in patients who underwent LPLND after the year 2000 were significantly lower than those who underwent LPLND before the year 2000 ((UD) RR = 4.5, p value = 0.0034; male SD RR = 28.7, p value < 0.001). CONCLUSION: Lateral pelvic lymph node dissection is associated with worse male sexual dysfunction compared to standard surgical resection. However, the rates of urine dysfunction and male sexual dysfunction are better in contemporary cohorts which may reflect improved surgical technique and autonomic nerve preservation.

The SIARI Score: A Novel Decision Support Tool Outperforms LRINEC Score in Necrotizing Fasciitis.

BACKGROUND: The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) scoring system was developed to aid the diagnosis of necrotizing fasciitis and guide management [1]. AIM: To validate the LRINEC score and identify clinical predictors to develop a refined diagnostic scoring tool for the diagnosis of necrotizing fasciitis at Middlemore Hospital, New Zealand. METHODS: This was a retrospective case-control study of patients admitted to Middlemore Hospital with necrotizing fasciitis and severe cellulitis between January 2000 and December 2010. The LRINEC scores at admission were evaluated for performance in discriminating between cases of necrotizing fasciitis and severe cellulitis. Cases and controls were randomized into developmental and validation cohorts. Univariate and multivariate logistic regression analysis of demographic, clinical, and laboratory variables for the diagnosis of necrotizing fasciitis was performed. The identified independent predictors were used to develop a new diagnostic scoring tool. RESULTS: The area under the receiver operating characteristic curve (C-statistic) of a LRINEC score ≥6 for the diagnosis of necrotizing fasciitis was 0.679. The newly developed SIARI score [Site other than the lower limb, Immunosuppression, Age < 60 years, Renal impairment (creatinine > 141), and Inflammatory markers (CRP ≥ 150, WCC > 25] demonstrated superior diagnostic ability compared with the LRINEC score in both the developmental (C-statistic: 0.832 vs. 0.691, p < 0.001) and validation cohorts (C-statistic: 0.847 vs. 0.667, p < 0.001). CONCLUSION: The LRINEC score exhibited only modest discriminative performance in this cohort, while the SIARI score is a simplified tool that demonstrates superior diagnostic ability for detecting necrotizing fasciitis. Future external validation studies are required to confirm the trends observed in this study.