Sadie L Dahlk

Bioelectrical impedance phase angle as a prognostic indicator in advanced pancreatic cancer

Bioelectrical impedance analysis (BIA) is an easy-to-use, non-invasive and reproducible technique to evaluate changes in body composition and nutritional status. Phase angle, determined by BIA, has been found to be a prognostic indicator in several chronic conditions, such as HIV, liver cirrhosis, chronic obstructive pulmonary disease and lung cancer, and in patients undergoing dialysis. The present study investigated the prognostic role of phase angle in advanced pancreatic cancer. We evaluated a case series of fifty-eight stage IV pancreatic cancer patients treated at Cancer Treatment Centers of America at Midwestern Regional Medical Center (Zion, IL, USA) between January 2000 and July 2003. BIA was conducted on all patients using a bioelectrical impedance analyser that operated at 50 kHz. The phase angle was calculated as capacitance (Xc)/resistance (R) and expressed in degrees. The Kaplan-Meier method was used to calculate survival. Cox proportional hazard models were constructed to evaluate the prognostic effect of phase angle independent of other clinical and nutritional variables. The correlations between phase angle and traditional nutritional measures were evaluated using Pearson and Spearman coefficients. Patients with phase angle <5.0 degrees had a median survival time of 6.3 (95% CI 3.5, 9.2) months (n 29), while those with phase angle >5.0 degrees had a median survival time of 10.2 (95% CI 9.6, 10.8) months (n 29); this difference was statistically significant (P=0.02). The present study demonstrates that phase angle is a strong prognostic indicator in advanced pancreatic cancer. Similar studies in other cancer settings with larger sample sizes are needed to further validate the prognostic significance of the phase angle.

Bioelectrical impedance phase angle as a prognostic indicator in breast cancer

BackgroundBioelectrical impedance analysis (BIA) is an easy-to-use, non-invasive, and reproducible technique to evaluate changes in body composition and nutritional status. Phase angle, determined by bioelectrical impedance analysis (BIA), detects changes in tissue electrical properties and has been hypothesized to be a marker of malnutrition. Since malnutrition can be found in patients with breast cancer, we investigated the prognostic role of phase angle in breast cancer.MethodsWe evaluated a case series of 259 histologically confirmed breast cancer patients treated at Cancer Treatment Centers of America. Kaplan Meier method was used to calculate survival. Cox proportional hazard models were constructed to evaluate the prognostic effect of phase angle independent of stage at diagnosis and prior treatment history. Survival was calculated as the time interval between the date of first patient visit to the hospital and the date of death from any cause or date of last contact/last known to be alive.ResultsOf 259 patients, 81 were newly diagnosed at our hospital while 178 had received prior treatment elsewhere. 56 had stage I disease at diagnosis, 110 had stage II, 46 had stage III and 34 had stage IV. The median age at diagnosis was 49 years (range 25 – 74 years). The median phase angle score was 5.6 (range = 1.5 – 8.9). Patients with phase angle <= 5.6 had a median survival of 23.1 months (95% CI: 14.2 to 31.9; n = 129), while those > 5.6 had 49.9 months (95% CI: 35.6 to 77.8; n = 130); the difference being statistically significant (p = 0.031). Multivariate Cox modeling, after adjusting for stage at diagnosis and prior treatment history found that every one unit increase in phase angle score was associated with a relative risk of 0.82 (95% CI: 0.68 to 0.99, P = 0.041). Stage at diagnosis (p = 0.006) and prior treatment history (p = 0.001) were also predictive of survival independent of each other and phase angle.ConclusionThis study demonstrates that BIA-derived phase angle is an independent prognostic indicator in patients with breast cancer. Nutritional interventions targeted at improving phase angle could potentially lead to an improved survival in patients with breast cancer.

Bioelectrical impedance phase angle in clinical practice: implications for prognosis in stage IIIB and IV non-small cell lung cancer

BackgroundA frequent manifestation of advanced lung cancer is malnutrition, timely identification and treatment of which can lead to improved patient outcomes. Bioelectrical impedance analysis (BIA) is an easy-to-use and non-invasive technique to evaluate changes in body composition and nutritional status. We investigated the prognostic role of BIA-derived phase angle in advanced non-small cell lung cancer (NSCLC).MethodsA case series of 165 stages IIIB and IV NSCLC patients treated at our center. The Kaplan Meier method was used to calculate survival. Cox proportional hazard models were constructed to evaluate the prognostic effect of phase angle, independent of stage at diagnosis and prior treatment history.Results93 were males and 72 females. 61 had stage IIIB disease at diagnosis while 104 had stage IV. The median phase angle was 5.3 degrees (range = 2.9 – 8). Patients with phase angle <= 5.3 had a median survival of 7.6 months (95% CI: 4.7 to 9.5; n = 81), while those with > 5.3 had 12.4 months (95% CI: 10.5 to 18.7; n = 84); (p = 0.02). After adjusting for age, stage at diagnosis and prior treatment history we found that every one degree increase in phase angle was associated with a relative risk of 0.79 (95% CI: 0.64 to 0.97, P = 0.02).ConclusionWe found BIA-derived phase angle to be an independent prognostic indicator in patients with stage IIIB and IV NSCLC. Nutritional interventions targeted at improving phase angle could potentially lead to an improved survival in patients with advanced NSCLC.

The relationship between bioelectrical impedance phase angle and subjective global assessment in advanced colorectal cancer

BackgroundBioelectrical Impedance (BIA) derived phase angle is increasingly being used as an objective indicator of nutritional status in advanced cancer. Subjective Global Assessment (SGA) is a subjective method of nutritional status. The objective of this study was to investigate the association between BIA derived phase angle and SGA in advanced colorectal cancer.MethodsWe evaluated a case series of 73 stages III and IV colorectal cancer patients. Patients were classified as either well-nourished or malnourished using the SGA. BIA was conducted on all patients and phase angle was calculated. The correlation between phase angle and SGA was studied using Spearman correlation coefficient. Receiver Operating Characteristic curves were estimated using the non-parametric method to determine the optimal cut-off levels of phase angle.ResultsWell-nourished patients had a statistically significantly higher (p = 0.005) median phase angle score (6.12) as compared to those who were malnourished (5.18). The Spearman rank correlation coefficient between phase angle and SGA was found to be 0.33 (p = 0.004), suggesting better nutritional status with higher phase angle scores.A phase angle cut-off of 5.2 was 51.7% sensitive and 79.5% specific whereas a cut-off of 6.0 was 82.8% sensitive and 54.5% specific in detecting malnutrition. Interestingly, a phase angle cut-off of 5.9 demonstrated high diagnostic accuracy in males who had failed primary treatment for advanced colorectal cancer.ConclusionOur study suggests that bioimpedance phase angle is a potential nutritional indicator in advanced colorectal cancer. Further research is needed to elucidate the optimal cut-off levels of phase angle that can be incorporated into the oncology clinic for better nutritional evaluation and management.

Can subjective global assessment of nutritional status predict survival in ovarian cancer

BackgroundMalnutrition is a significant problem in patients with ovarian cancer. The goal of this study was to investigate the prognostic role of Subjective Global Assessment (SGA) in patients with ovarian cancer treated in an integrative cancer treatment setting.MethodsWe evaluated a case series of 132 ovarian cancer patients treated at Cancer Treatment Centers of America® from Jan 2001 to May 2006. SGA was used to assess nutritional status at baseline. Using SGA, patients were classified as well nourished (SGA A), moderately malnourished (SGA B) or severely malnourished (SGA C). Kaplan Meier method was used to calculate survival. Cox proportional hazard models were constructed to evaluate the prognostic effect of SGA independent of other factors.ResultsOf 132 patients, 24 were newly diagnosed while 108 had received prior treatment. 15 had stage I disease at diagnosis, 8 stage II, 85 stage III and 17 stage IV. The median age at presentation was 54.4 years (range 25.5 – 82.5 years). 66 patients were well-nourished (SGA A), 35 moderately malnourished (SGA B) and 31 severely malnourished (SGA C). Well nourished patients had a median survival of 19.3 months (95% CI: 14.1 to 24.5), moderately malnourished 15.5 months (95% CI: 5.8 to 25.1), and severely malnourished 6.7 months (95% CI: 4.1 to 9.3); the difference being statistically significant (p = 0.0003). Multivariate Cox modeling, after adjusting for stage at diagnosis and prior treatment history found that moderately malnourished and severely malnourished status were associated with a relative risk of 2.1 (95% CI: 1.2 to 3.6, p = 0.008) and 3.4 (95% CI: 1.9 to 5.8, p < 0.001) respectively as compared to well nourished status.ConclusionUnivariate and multivariate survival analyses found that low SGA scores (i.e. well-nourished status) are associated with better survival outcomes. This study lends support to the role of aggressive nutritional intervention in improving patient outcomes in cancer care.

A longitudinal study investigating quality of life and nutritional outcomes in advanced cancer patients receiving home parenteral nutrition

BackgroundIn cancer patients where gastrointestinal function is marginal and malnutrition significant enough to result in the requirement for intensive nutrition support, parenteral nutrition (PN) is indicated. This longitudinal study examined the quality of life (QoL) and nutritional outcomes in advanced cancer patients receiving home PN (HPN).MethodsFifty-two adult cancer patients (21 males, 31 females, average age 53 years) treated at a specialized cancer facility between April 2009 and November 2011 met criteria. QoL and nutritional status were measured at baseline and every month while on HPN using EORTC-QLQ-C30, Karnofsky Performance Status (KPS), and Subjective Global Assessment (SGA). Repeated measures ANOVA and Generalized Estimating Equations (GEE) were used to evaluate longitudinal changes in QoL and SGA.ResultsCancer diagnoses included pancreatic (n = 14), colorectal (n = 11), ovarian (n = 6), appendix (n = 5), stomach (n = 4) and others (n = 12). Average weight loss 6-months prior to HPN was 13.2 kg (16.9%). Average weight at initiation of HPN was 62.2 kg. In patients with available follow-up data after 1 month (n = 39), there was a significant improvement in SGA, weight (61.5 to 63.1 kg; p = 0.03) and KPS (61.6 to 67.3; p = 0.01) from baseline. Similarly, after 2 months (n = 22), there was an improvement in global QoL (37.1 to 49.2; p = 0.02), SGA, weight (57.6 to 60 kg; p = 0.04) and KPS (63.2 to 73.2; p = 0.01) from baseline. Finally, after 3 months (n = 15), there was an improvement in global QoL (30.6 to 54.4; p = 0.02), SGA, weight (61.1 to 65.9 kg; p = 0.04) and KPS (64.0 to 78.7; p = 0.002) from baseline. Upon GEE analysis, every 1 month of HPN was associated with an increase of 6.3 points in global QoL (p<0.001), 1.3 kg in weight (p = 0.009) and 5.8 points in KPS (p<0.001).ConclusionsHPN is associated with an improvement in QoL, KPS and nutritional status in advanced cancer patients, irrespective of their tumor type, who have compromised enteral intake and malnutrition. The greatest benefit was seen in patients with 3 months of HPN, although patients receiving HPN for 1 or 2 months also demonstrated significant improvements.

Percutaneous endoscopic gastrostomy tube occlusion in malignant peritoneal carcinomatosis-induced bowel obstruction.

Objective Percutaneous endoscopic gastrostomy (PEG) tube placement for decompression in advanced peritoneal carcinomatosis with bowel obstruction is a safe and feasible palliative procedure. We describe a rare, previously unreported phenomenon of PEG tube occlusion by gastric mucosal herniation. Methods A consecutive case series of 73 patients with advanced abdominal carcinomatosis-induced bowel obstruction from January 2007 to June 2010. All patients had a 28 Fr (Bard) PEG tube placed for drainage. None of them were surgical candidates due to extensive peritoneal involvement. Patients with PEG tube occlusion as a result of gastric mucosal herniation were further evaluated. Results Nineteen patients were men and 54 were women. The mean age was 53.3 years. The most common cancer types were ovary, pancreas, colon, and stomach. All patients had PEG tube functioning well after the procedure with immediate relief of obstructive symptoms. Subsequently, 10 patients developed acute occlusion of PEG tubes with reoccurrence of obstructive symptoms. The time between the placement of the PEG tube and its occlusion ranged from 5 to 129 days. Repeat endoscopy showed the PEG tube occluded with gastric mucosa from the opposite wall. PEG tube was replaced with a 28 Fr balloon replacement tube leading to symptom improvement in all 10 patients. Conclusion This rare but correctable phenomenon of obliteration of PEG tube from the gastric mucosa should be considered in any patient who develops intermittent occlusive symptoms. This phenomenon can be corrected by replacing the PEG tube with a ballooned replacement tube as well as occasional manipulation of the tube.

Clinical and Nutritional Correlates of Survival in Breast Cancer.

Background: Malnutrition can be a frequent manifestation of breast cancer and its treatment. Several nutritional assessment tools have varying levels of association with survival, and have been tested individually with different patient populations, sometimes making it difficult to assess the impact of one tool relative to the others. We therefore conducted a single-institution multivariate analysis of 3 most commonly used nutritional tools - Body Mass Index (BMI), Subjective Global Assessment (SGA) and bioimpedance-derived phase angle (PA).Material and Methods: A case series of 234 breast cancer patients treated at Cancer Treatment Centers of America. Using SGA, patients were classified as well nourished (SGA A), moderately malnourished (SGA B) or severely malnourished (SGA C). Cox proportional hazard models were used to evaluate the independent prognostic effects of SGA, PA and BMI after controlling for each other, stage at diagnosis and prior treatment history (newly diagnosed versus previously treated).Results: Of 234 patients, 74 were newly diagnosed while 160 had received prior treatment. 159 had early stage (I/II) disease at diagnosis, while 75 had late stage (III/IV). The median age at presentation was 52.8 years (range 25-75 years). The mean PA and BMI scores were 5.5 (std. dev = 1.1) and 28.7 (std. dev = 6.2) respectively. 171 patients were well-nourished (SGA A) while 63 were malnourished (SGA B/C). Multivariate Cox modeling, after adjusting for stage at diagnosis, prior treatment history and other nutritional variables, found that malnourished status (SGA B/C) was associated with a relative risk (RR) of 2.4 (95% CI: 1.5-3.9, p Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6048.