Role of sentinel node biopsy in the management and staging of the N0 neck

Sentinel node biopsy is being increasingly used as a staging tool for mucosal head and neck cancer. This review of the literature summarizes the results of research into the procedure when it has been performed in three main contexts: as part of an ipsilateral neck dissection, as a stand-alone procedure to stage the neck for positive or negative disease, and as a means of investigating the non-involved or contralateral neck in tumors close to or crossing the midline. The role of the procedure is discussed and the difficulties encountered are expanded, with a particular emphasis on pitfalls of the technique, caveats, and its potential role for the future.     

The influence of the mode of delivery on circulating cytokine concentrations in the perinatal period

BACKGROUND: Cytokines play an important role during labor and full- or preterm delivery. They influence physical immunity of the fetus-neonate and express a leading role in the perinatal period, being present in maternal and fetal tissues. AIM: To investigate whether cytokine concentrations in the mother, fetus and neonate depend on the labor and the mode of the delivery. STUDY DESIGN: Prospective study. SUBJECTS: Seventy-eight healthy, non-smoking parturients (mean age 28+/-4, range 21-39 years, delivering vaginally: n=52 or by elective cesarean section: n=26) and their single, healthy, appropriate for gestational age, full-term neonates. OUTCOME MEASURES: We correlated determined circulating levels of IL-2, sIL-2R, IL-4, sIL-4R, IL-6, sIL-6R, IL-1beta, IL-8, IFN-gamma, TNF-alpha, sTNF RI, sTNF RII and RANTES in the mothers before delivery (MS), the fetuses (UC) and the neonates in days 1 (N1) and 4 (N4) of life, with the mode of delivery. RESULTS: sIL-2R in N1 and N4, sIL-4R in MS, IL-6 in MS and UC, IL-1beta in MS, UC and N1, IFN-gamma in MS and UC, TNF-alpha in UC, N1 and N4, sTNF RI in UC were significantly higher in cases of vaginal delivery than in cases of elective cesarean section (p ranging from 0.0005 to 0.05). CONCLUSIONS: Vaginal delivery promotes the production of various cytokines and their receptors, which are implicated in neonatal immunity.     

The impact of labor at term on measures of neonatal outcome

OBJECTIVE: The purpose of this study was to determine risk assessments for a spectrum of neonatal outcomes with elective cesarean delivery versus a trial of labor for previous cesarean section and otherwise healthy patients who deliver at term. STUDY DESIGN: The perinatal/neonatal database of St. Joseph's Health Care, London, Ontario, Canada, was used to obtain the umbilical cord pH and base excess values, incidence of adverse neonatal outcomes, and patient demographics for all term (> or =37 weeks of gestation), singleton, liveborn, or intrapartum demise infants with no major anomalies who were delivered between January 1992 and March 2002 (n = 33,709 infants). Patient groupings (all patient, patient with previous cesarean delivery, and low-risk patient) with no labor versus labor were studied by a comparison of mean values/incidences for those neonatal outcomes that were available from the database with the use of linear and logistic regression analysis and controlling for potentially confounding variables. RESULTS: Labor was associated with a small drop in umbilical artery pH from approximately 7.27 to 7.25 and base excess from approximately -3.1 to -5.4 mmol/L, but this was generally well tolerated, with no difference in the incidence of 5-minute Apgar scores of <7 for any of the patient population groupings. Neonatal respiratory morbidity was increased generally in the group of elective cesarean delivery patients, which resulted in increased neonatal intensive care unit triage/admission even out to 7 days; some of this risk was likely to persist even with a policy of elective cesarean delivery after 39 weeks of gestation. Although we found no significant difference in the incidence of pathologic acidemia at birth with an umbilical artery pH <7.00, there was a risk for intrapartum/neonatal death that could be attributed to labor events per se that ranged from 1 of 882 for the patients with previous cesarean delivery to 1 of 3406 for the low-risk patients. CONCLUSION: For otherwise healthy patients at term, the risk of adverse neonatal outcomes is low, with the choice between elective cesarean delivery and trial of labor in general balancing the low risk of increased respiratory morbidity and thereby neonatal intensive care unit triage/admission against the extremely low risk of labor-related infant death and severe morbidity. However, this balance for the patients with previous cesarean delivery appears shifted, with less benefit from a trial of labor in terms of reduced respiratory morbidity and neonatal intensive care unit triage/admission and with increased labor-related severe morbidity/death, albeit with all of these still at a low level.     

Comparison of maternal mortality and morbidity between trial of labor and elective cesarean section among women with previous cesarean delivery

OBJECTIVE: This study was undertaken to assess the safety of trial of labor after previous cesarean delivery. STUDY DESIGN: Retrospective cohort study of 308,755 Canadian women with previous cesarean delivery between 1988 and 2000. Occurrences of in-hospital maternal death, uterine rupture, and other severe maternal morbidity were compared between women with a trial of labor and those with an elective cesarean section. RESULTS: Rates of uterine rupture (0.65%), transfusion (0.19%), and hysterectomy (0.10%) were significantly higher in the trial-of-labor group. Maternal in-hospital death rate, however, was lower in the trial-of-labor group (1.6 per 100,000) than in the elective cesarean section group (5.6 per 100,000). The association between trial of labor and uterine rupture was stronger in low volume (<500) than in high volume (> or =500 births per year) obstetric units. CONCLUSION: Trial of labor is associated with increased risk of uterine rupture, but elective cesarean section may increase the risk of maternal death.     

Pathophysiologic changes and effects of hypothermia on outcome in elective surgery and trauma patients

Generally, hypothermia is defined as a core temperature <35 degrees C. In elective surgery, induced hypothermia has beneficial effects. It is recommended to diminish complications attributable to ischemia reperfusion injury. Experimental studies have shown that hypothermia during hemorrhagic shock has beneficial effects on outcome. In contrast, clinical experience with hypothermia in trauma patients has shown accidental hypothermia to be a cause of posttraumatic complications. The different etiology of hypothermia might be one reason for this disparity because induced therapeutic hypothermia, with induction of poikilothermia and shivering prevention, is quite different from accidental hypothermia, which results in physiological stress. Other studies have shown evidence that this contradictory effect is related to the plasma concentration of high-energy phosphates (e.g., adenosine triphosphate [ATP]). Induced hypothermia preserves ATP storage, whereas accidental hypothermia causes depletion. Hypothermia also has an impact on the immunologic response after trauma and elective surgery by decreasing the inflammatory response. This might have a beneficial effect on outcome. Nevertheless, posttraumatic infectious complications may be higher because of an immunosuppressive profile. Further studies are needed to investigate the impact of induced hypothermia on outcome in trauma patients.     

Sentinel Node Biopsy Provides More Accurate Staging Than Elective Lymph Node Dissection in Patients With Cutaneous Melanoma

Background: In most major melanoma treatment centers, sentinel node biopsy (SNB), with complete regional lymph node dissection when a positive sentinel node is found, has now replaced elective lymph node dissection (ELND) for patients with primary cutaneous melanomas who are considered to be at moderate to high risk of nodal recurrence. As for ELND, however, no overall survival benefit for the SNB procedure has yet been demonstrated. The objective of this study was to compare the nodal staging accuracy and duration of survival for SNB and ELND.Methods: A retrospective cohort study was conducted among patients with American Joint Committee on Cancer (AJCC) stage II disease treated at a single center between 1983 and 2000 with either SNB (n = 672) or ELND (n = 793). Multivariate analyses were performed using the logistic regression model for nodal staging accuracy and Coxs proportional hazards regression model for survival.Results: Patient factors that influenced nodal positivity included age, Breslow thickness, ulceration, head or neck primary, and operation type (SNB or ELND). SNB was superior to ELND in the detection of micrometastases (odds ratio 1.23, 95% CI, 1.06 – 1.43) but operation type did not influence survival (P = .24).Conclusions: Sentinel node biopsy identified more nodal micrometastases than ELND but did not influence survival, although complete regional node dissection was performed in all patients who were SNB positive. This increase in staging accuracy likely results from the reliable identification of the appropriate lymph node field by preoperative lymphoscintigraphy, along with more detailed pathologic examination of the nodes removed by SNB.Presented to the Society of Surgical Oncology, New York, March 2004     

Predictors of subclinical nodal involvement in clinical stages I and II non-small cell lung cancer: implications in the inoperable and three-dimensional dose-escalation settings

Purpose: When mediastinal lymph nodes are clinically uninvolved in the setting of inoperable non-small cell lung cancer, whether conventional radiation techniques or three-dimensional dose-escalation techniques are used, the benefit of elective nodal irradiation is unclear. Inclusion of the clinically negative mediastinum in the radiation portals increases the risk of lung toxicity and limits the ability to escalate dose. This analysis represents an attempt to use clinical characteristics to estimate the risk of subclinical nodal involvement, which may help determine which patients are most likely to benefit from elective nodal irradiation.

Methods: From 1987 to 1990, 346 patients undergoing complete resection of non-small cell lung cancer underwent a preoperative computed tomographic scan revealing no clinical evidence of N2/N3 involvement. Multivariate regression and regression tree analyses attempted to define which patients were at highest risk for subclinical mediastinal involvement (N2) and which patients were at highest risk for subclinical N1 and/or N2 involvement (N1/N2). Immunohistochemical data suggest that the conventional histopathologic techniques used during this study somewhat underestimate the true degree of lymph node involvement; therefore, a third end point was also evaluated: N1 involvement and/or N2 involvement and/or local-regional recurrence (N1/N2/LRR).

Results: Regression analyses revealed that the following factors were independently associated with a high risk of more advanced disease: positive preoperative bronchoscopy (N2, p = 0.02; N1/N2, p < 0.0001; N1/N2/LRR, p < 0.001) and tumor grade 3/4 (N1/N2/LRR, p < 0.01). A regression tree analysis was then used to separate patients into risk groups with respect to N1/N2/LRR.

Conclusion: In inoperable non-small cell lung cancer, the patients for whom mediastinal radiation therapy may most likely be indicated are those with a positive preoperative bronchoscopy, especially with large (> 3 cm) primary tumors.     

Prevalence of stress incontinence among women delivered by elective cesarian section

A retrospective investigation into the prevalence of stress incontinence in women delivered by elective cesarian section (without experience of labor) in Lund from 1974 to 1979, was carried out in 1980. Of 264 women whose replies were solicited, 204 responded. The others had moved about and could not be reached. Permanent stress incontinence was reported by a significant number of patients without experience of labor. This supports our earlier findings which indicated that pregnancy and hereditary factors are more decisive in bringing about stress incontinence than the delivery itself.     

术前口服糖类溶液对结肠癌病人术后即时胰岛素抵抗的影响

目的:评价术前口服糖类溶液对择期结肠癌病人术后即时胰岛素抵抗的影响. 方法:随机将择期结肠癌手术病人32例分为两组,对照组术前常规禁食禁水,试验组在术前3 h给予糖类溶液口服.分别在手术前1天15:00和手术当天早晨服药后2 h用视觉模拟评分法(VAS)测定两组病人的主观舒适度;在术前4 h及术后即刻抽取外周血测定血清葡萄糖和胰岛素浓度,并用稳态模式评估法(HOMA)计算胰岛素抵抗指数、胰岛素分泌指数和胰岛素敏感指数等. 结果:术前口服糖类溶液,可明显减轻术前1 h的口渴感、饥饿感和焦虑感.对照组术后胰岛素敏感指数下降了38%,而试验组下降了33%(P<0.01).试验组的胰岛素抵抗程度较对照组改善37%. 结论:术前口服糖类溶液安全有效,可改善病人术后即时胰岛素抵抗.