Thyroid surgery with a harmonic scalpel: an experimental study.

BACKGROUND: The goal of the study was to determinate the safety of the harmonic scalpel, widely used in thyroidectomy, near the recurrent laryngeal nerve (RLN). METHODS: The study involved ten pigs of either sex. Twenty RLNs at risk were dissected using the new harmonic scalpel FOCUS. The distances between the nerve and the activated instrument were checked with a millimeter ruler. After dissection, the pigs were euthanized, and both RLNs were fixed in formol and examined by histology after staining with hematoxylin-eosin. Due to technical reasons, only 18 RLNs from the ten pigs could be examined. RESULTS: In the experiment that investigated the extent of heat injury, ultrasonic dissection did not cause any immediate damage of the nerve even close to the RLN (1 mm away from the RLN). CONCLUSION: The use of harmonic scalpel FOCUS for thyroid surgery is safe for the surrounding structures (nerves). Careful tissue applications of the device near the RLN (1 mm) did not cause any lesion histologically.

Prognostic value of lymph node ratio for locoregional failure in patients with advanced head and neck cancers.

BACKGROUND: In the current study, the utility of lymph node ratio (LNR) was evaluated as an alternative method for predicting locoregional failure in patients with advanced head and neck cancer. METHODS: Fifty-six patients with oral and (pharyngo)laryngeal squamous cell carcinoma were included. Among those, 48 were males and 8 females, with a mean age of 58 years. The primary tumor was located in the oral cavity in 16 cases, involved the larynx in 17 cases and the hypopharynx in 23 cases. All the tumors were staged T4. We carried out 112 neck dissections. All the lymph nodes harvested from the neck dissection were carefully examined, with LNR calculated as the ratio of positive lymph nodes to total lymph nodes removed. All the patients received adjuvant (chemo)radiotherapy. RESULTS: Receiver operating characteristic curve analysis showed LNR was significantly associated with locoregional failure. LNR >0.09 (as the cutoff point) could predict locoregional failure after surgery for oral and (pharyngo)laryngeal cancers with a sensibility of 93% and specificity of 100%. CONCLUSIONS: After surgery, pathologic evaluation of the neck using LNR was found to reliably predict the risk of locoregional recurrence in patients with advanced head and neck cancers.

A lymph node ratio of 10% is predictive of survival in stage III colon cancer: a French regional study.

Lymph node ratio (LNR) (positive lymph nodes/sampled lymph nodes) is predictive of survival in colon cancer. The aim of the present study was to validate the LNR as a prognostic factor and to determine the optimum LNR cutoff for distinguishing between "good prognosis" and "poor prognosis" colon cancer patients. From January 2003 to December 2007, patients with TNM stage III colon cancer operated on with at least of 3 years of follow-up and not lost to follow-up were included in this retrospective study. The two primary endpoints were 3-year overall survival (OS) and disease-free survival (DFS) as a function of the LNR groups and the cutoff. One hundred seventy-eight patients were included. There was no correlation between the LNR group and 3-year OS (P=0.06) and a significant correlation between the LNR group and 3-year DFS (P=0.03). The optimal LNR cutoff of 10% was significantly correlated with 3-year OS (P=0.02) and DFS (P=0.02). The LNR was not an accurate prognostic factor when fewer than 12 lymph nodes were sampled. Clarification and simplification of the LNR classification are prerequisites for use of this system in randomized control trials. An LNR of 10% appears to be the optimal cutoff.