A prognostic system for epithelial ovarian carcinomas using machine learning.

INTRODUCTION: Integrating additional factors into the International Federation of Gynecology and Obstetrics (FIGO) staging system is needed for accurate patient classification and survival prediction. In this study, we tested machine learning as a novel tool for incorporating additional prognostic parameters into the conventional FIGO staging system for stratifying patients with epithelial ovarian carcinomas and evaluating their survival. MATERIAL AND METHODS: Cancer-specific survival data for epithelial ovarian carcinomas were extracted from the Surveillance, Epidemiology, and End Results (SEER) program. Two datasets were constructed based upon the year of diagnosis. Dataset 1 (39 514 cases) was limited to primary tumor (T), regional lymph nodes (N) and distant metastasis (M). Dataset 2 (25 291 cases) included additional parameters of age at diagnosis (A) and histologic type and grade (H). The Ensemble Algorithm for Clustering Cancer Data (EACCD) was applied to generate prognostic groups with depiction in dendrograms. C-indices provided dendrogram cutoffs and comparisons of prediction accuracy. RESULTS: Dataset 1 was stratified into nine epithelial ovarian carcinoma prognostic groups, contrasting with 10 groups from FIGO methodology. The EACCD grouping had a slightly higher accuracy in survival prediction than FIGO staging (C-index = 0.7391 vs 0.7371, increase in C-index = 0.0020, 95% confidence interval [CI] 0.0012-0.0027, p = 1.8 × 10-7 ). Nevertheless, there remained a strong inter-system association between EACCD and FIGO (rank correlation = 0.9480, p = 6.1 × 10-15 ). Analysis of Dataset 2 demonstrated that A and H could be smoothly integrated with the T, N and M criteria. Survival data were stratified into nine prognostic groups with an even higher prediction accuracy (C-index = 0.7605) than when using only T, N and M. CONCLUSIONS: EACCD was successfully applied to integrate A and H with T, N and M for stratification and survival prediction of epithelial ovarian carcinoma patients. Additional factors could be advantageously incorporated to test the prognostic impact of emerging diagnostic or therapeutic advances.

Evaluation of Surgical Disparities Between African American and European American Women Treated for Breast Cancer Within an Equal-Access Military Hospital.

BACKGROUND: Survival disparities between African American women (AAW) and European American women (EAW) with invasive breast cancer may be attributable, in part, to access to or quality of medical care. In this study, we evaluated surgical disparities between AAW and EAW treated within an equal-access military treatment facility (MTF). METHODS: All AAW (N = 271) and EAW (N = 628) with Stage I-III breast cancer who had their initial diagnosis performed at Murtha Cancer Center at Walter Reed National Military Medical Center were identified. Differences in surgical interval (time between diagnosis and definitive breast surgery) and surgical procedures were evaluated using χ2 and Student t-tests while survival was analyzed using Kaplan-Meier survival estimates and log-rank tests. A P value < 0.05 was used to define significance. RESULTS: Surgical intervals did not differ significantly between populations with an average of 36.3 days in AAW and 33.9 days in EAW. Frequency of the percentage of women undergoing reexcision, mastectomy, and prophylactic removal of the contralateral breast did not differ significantly between populations. Likewise, frequency of sentinel lymph node biopsy and 5-year survival were not significantly different between AAW compared to EAW. DISCUSSION: Surgical intervals and procedures were similar between AAW and EAW treated within an equal-access MTF. These data demonstrate that the availability of quality surgical care to all patients with stage I-III breast cancer may eliminate survival disparities between AAW and EAW, emphasizing the importance of equalizing access to breast care.

An algorithm for expanding the TNM staging system.

AIM: We describe a new method to expand the tumor, lymph node, metastasis (TNM) staging system using a clustering algorithm. Cases of breast cancer were used for demonstration. MATERIALS & METHODS: An unsupervised ensemble-learning algorithm was used to create dendrograms. Cutting the dendrograms produced prognostic systems. RESULTS: Prognostic systems contained groups of patients with similar outcomes. The prognostic systems based on tumor size and lymph node status recapitulated the general structure of the TNM for breast cancer. The prognostic systems based on tumor size, lymph node status, histologic grade and estrogen receptor status revealed a more detailed stratification of patients when grade and estrogen receptor status were added. CONCLUSION: Prognostic systems from cutting the dendrogram have the potential to improve and expand the TNM.

An Algorithm for Creating Prognostic Systems for Cancer.

The TNM staging system is universally used for classification of cancer. This system is limited since it uses only three factors (tumor size, extent of spread to lymph nodes, and status of distant metastasis) to generate stage groups. To provide a more accurate description of cancer and thus better patient care, additional factors or variables should be used to classify cancer. In this paper we propose a hierarchical clustering algorithm to develop prognostic systems that classify cancer according to multiple prognostic factors. This algorithm has many potential applications in augmenting the data currently obtained in a staging system by allowing more prognostic factors to be incorporated. The algorithm clusters combinations of prognostic factors that are formed using categories of factors. The dissimilarity between two combinations is determined by the area between two corresponding survival curves. Groups from cutting the dendrogram and survival curves of the individual groups define our prognostic systems that classify patients using survival outcomes. A demonstration of the proposed algorithm is given for patients with breast cancer from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute.

Clinical Readiness Program: Refocusing the Military Health System.

INTRODUCTION: The Military Health System serves to globally provide health services and trained medical forces. Military providers possess variable levels of deployment preparedness. The aim of the Clinical Readiness Program is to develop and assess the knowledge, skills, and abilities (KSAs) needed for combat casualty care. METHODS: The Clinical Readiness Program developed a KSA metric for general and orthopedic surgery. The KSA methodology underwent a proof of concept in six medical treatment facilities. RESULTS: The KSA metric feasibly quantifies the combat relevance of surgical practice. Orthopedic surgeons are more likely than general surgeons to meet the threshold. Medical treatment facilities do not provide enough demand for general surgery services to achieve readiness. CONCLUSION: The Clinical Readiness Program identifies imbalances between the health care delivery and readiness missions. To close the readiness gap, the Military Health System needs to recapture high KSA value procedures, expand access to care, and/or partner with civilian institutions.

Integrating additional factors into the TNM staging for cutaneous melanoma by machine learning.

BACKGROUND: Integrating additional factors into the TNM staging system is needed for more accurate risk classification and survival prediction for patients with cutaneous melanoma. In the present study, we introduce machine learning as a novel tool that incorporates additional prognostic factors to improve the current TNM staging system. METHODS AND FINDINGS: Cancer-specific survival data for cutaneous melanoma with at least a 5 years follow-up were extracted from the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute and split into the training set (40,781 cases) and validation set (5,390 cases). Five factors were studied: the primary tumor (T), regional lymph nodes (N), distant metastasis (M), age (A), and sex (S). The Ensemble Algorithm for Clustering Cancer Data (EACCD) was applied to the training set to generate prognostic groups. Utilizing only T, N, and M, a basic prognostic system was built where patients were stratified into 10 prognostic groups with well-separated survival curves, similar to 10 AJCC stages. These 10 groups had a significantly higher accuracy in survival prediction than 10 stages (C-index = 0.7682 vs 0.7643; increase in C-index = 0.0039, 95% CI = (0.0032, 0.0047); p-value = 7.2×10-23). Nevertheless, a positive association remained between the EACCD grouping and the AJCC staging (Spearman's rank correlation coefficient = 0.8316; p-value = 4.5×10-13). With additional information from A and S, a more advanced prognostic system was established using the training data that stratified patients into 10 groups and further improved the prediction accuracy (C-index = 0.7865 vs 0.7643; increase in C-index = 0.0222, 95% CI = (0.0191, 0.0254); p-value = 8.8×10-43). Both internal validation using the training set and temporal validation using the validation set showed good stratification and a high predictive accuracy of the prognostic systems. CONCLUSIONS: The EACCD allows additional factors to be integrated into the TNM to create a prognostic system that improves patient stratification and survival prediction for cutaneous melanoma. This integration separates favorable from unfavorable clinical outcomes for patients and improves both cohort selection for clinical trials and treatment management.

The impact of HER2/neu expression level on response to the E75 vaccine: from U.S. Military Cancer Institute Clinical Trials Group Study I-01 and I-02.

PURPOSE: HER2/neu, a source of immunogenic peptides, is expressed in >75% of breast cancer patients. We have conducted clinical trials with the HER2/neu E75 peptide vaccine in breast cancer patients with varying levels of HER2/neu expression. Vaccine response based on HER2/neu expression level was analyzed. EXPERIMENTAL DESIGN: Patients were stratified by HER2/neu expression. Low expressors (n = 100) were defined as HER2/neu immunohistochemistry (IHC) 1(+) to 2(+) or fluorescence in situ hybridization < 2.0. Overexpressors (n = 51) were defined as IHC 3(+) or fluorescence in situ hybridization > or = 2.0. Additional analyses were done stratifying by IHC status (0-3(+)). Standard clinocopathlogic factors, immunologic response (in vivo delayed-type hypersensitivity reactions; ex vivo human leukocyte antigen A2:immunoglobulin G dimer assay), and clinical responses (recurrence; mortality) were assessed. RESULTS: Low-expressor (control, 44; vaccinated, 56) versus overexpressor patients (control, 22; vaccinated, 29) were assessed. Low expressors, overexpressors, and most IHC-status vaccinated groups responded immunologically. Vaccinated low-expressor patients had larger maximum immunologic responses compared with overexpressor patients (P = 0.04), and vaccinated IHC 1(+) patients had increased long-term immune response (P = 0.08). More importantly, compared with controls, low-expressor patients had a mortality reduction (P = 0.08). The largest decrease in mortality was seen in IHC 1(+) patients (P = 0.05). In addition, a subset of overexpressor patients (n = 7) received trastuzumab before vaccination, and this combination seems safe and immunologically beneficial. CONCLUSIONS: Most patients with various levels of HER2/neu expression responded immunologically and seemed to benefit from vaccination. The low expressors, specifically IHC 1(+) patients, had more robust immunologic responses and may derive the greatest clinical benefit from the E75 vaccine.

Evolving treatment strategies for gallbladder cancer.

Gallbladder cancer is an uncommon cancer that has traditionally been associated with a poor prognosis. In the era of laparoscopic cholecystectomy, incidental gallbladder cancer has dramatically increased and now constitutes the major way patients present with gallbladder cancer. While patients with incidental gallbladder cancer have a better survival than patients with nonincidental gallbladder cancer, incidental gallbladder cancer can be associated with a varied prognosis. Imaging with computed tomography (CT), magnetic resonance imaging (MRI), and [18]F-fluorodeoxyglucose (FDG) positron emission tomography (PET), as well as diagnostic laparoscopy, all have varying roles in the workup of patients with incidental gallbladder cancer. For patients with T1b, T2, and T3 incidental gallbladder cancer re-resection is generally recommended. At re-exploration, many patients with incidental gallbladder cancer will have residual disease. Definitive oncologic management requires re-resection of the liver, portal lymphadenectomy, and attention to the common bile duct. The extent of the hepatic resection should be dictated by the ability to achieve a microscopically negative (R0) margin. Routine resection of the common bile duct is unnecessary but should be undertaken in the setting of a positive cystic duct margin. If an incidental gallbladder cancer is discovered at the time of surgery, whether the surgeon should directly proceed with a more definitive oncologic operation should depend on the surgeon's skill-set and experience. Gallbladder cancer has a propensity to recur. Although data for adjuvant therapy following resection are limited, some data do suggest a survival benefit for adjuvant chemoradiation therapy. Management of patients with gallbladder cancer requires a multidisciplinary approach with input from a surgeon skilled in hepatobiliary surgery.

Combined clinical trial results of a HER2/neu (E75) vaccine for the prevention of recurrence in high-risk breast cancer patients: U.S. Military Cancer Institute Clinical Trials Group Study I-01 and I-02.

PURPOSE: E75 is an immunogenic peptide from the HER2/neu protein, which is overexpressed in many breast cancer patients. We have conducted two overlapping E75 vaccine trials to prevent recurrence in node-positive (NP) and node-negative (NN) breast cancer patients. EXPERIMENTAL DESIGN: E75 (HER2/neu 369-377) + granulocyte macrophage colony-stimulating factor was given intradermally to previously treated, disease-free NP breast cancer patients in a dose escalation safety trial and to NN breast cancer patients in a dose optimization study. Local and systemic toxicity was monitored. Immunologic responses were assessed using in vitro assays and in vivo delayed-type hypersensitivity responses. Clinical recurrences were documented. RESULTS: One hundred and eighty-six patients were enrolled in the two studies (NP, 95; NN, 91). Human leucocyte antigen A2 (HLA-A2) and HLA-A3 patients were vaccinated (n = 101), whereas all others (n = 85) were followed prospectively as controls. Toxicities were minimal, and a dose-dependent immunologic response to the vaccine was shown. Planned primary analysis revealed a recurrence rate of 5.6% in vaccinated patients compared with 14.2% in the controls (P = 0.04) at a median of 20 months follow-up. As vaccine-specific immunity waned over time, the difference in recurrence lost significance at 26 months median follow-up (8.3% versus 14.8%); however, a significant difference in the pattern of recurrence persisted. CONCLUSIONS: E75 is safe and effective in raising a dose-dependent HER2/neu immunity in HLA-A2 and HLA-A3 NP and NN breast cancer patients. More importantly, E75 may reduce recurrences in disease-free, conventionally treated, high-risk breast cancer patients. These findings warrant a prospective, randomized phase III trial of the E75 vaccine with periodic booster to prevent breast cancer recurrences.

Creating Prognostic Systems for Well-Differentiated Thyroid Cancer Using Machine Learning.

Updates to staging models are needed to reflect a greater understanding of tumor behavior and clinical outcomes for well-differentiated thyroid carcinomas. We used a machine learning algorithm and disease-specific survival data of differentiated thyroid carcinoma from the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute to integrate clinical factors to improve prognostic accuracy. The concordance statistic (C-index) was used to cut dendrograms resulting from the learning process to generate prognostic groups. We created one computational prognostic model (7 prognostic groups with C-index = 0.8583) based on tumor size (T), regional lymph nodes (N), status of distant metastasis (M), and age to mirror the contemporary American Joint Committee on Cancer (AJCC) staging system (C-index = 0.8387). We showed that adding histologic type (papillary and follicular) improved the survival prediction of the model. We also showed that 55 is the best cutoff of age in the model, consistent with the changes from the most recent 8th edition staging manual from AJCC. The demonstrated approach has the potential to create prognostic systems permitting data driven and real time analysis that can aid decision-making in patient management and prognostication.

Management of gastrointestinal stromal tumors.

A gastrointestinal stromal tumor (GIST) is a rare mesenchymal malignancy of the gastrointestinal (GI) tract. Malignant GISTs were first defined as a separate entity from a collection of nonepithelial malignancies of the GI tract in the 1980s and 1990s based on pathologic and clinical behavior. The discovery of activating KIT mutations as a near-uniform occurrence in these tumors greatly influenced the classification [1] and revolutionized therapeutic management of these tumors. To meet the next challenges, newer tyrosine kinase inhibitors and targeted agents are being developed with the goal of providing improved response rates or alternative therapies for patients progressing on established agents. In this article, the authors describe the management of GISTs, concentrating on surgical management and targeted therapies.

Management of retroperitoneal sarcomas.

Retroperitoneal sarcomas present a therapeutic challenge based on their location, extent of invasion at diagnosis, and propensity for local recurrence. Surgical therapy remains the only potentially curative treatment option; however, even with aggressive surgical approaches, local recurrence remains a common type of failure. For patients who have high-grade lesions, distant metastatic disease may also limit survival. Optimizing disease control while minimizing the morbidity of therapy remains the primary goal of management. In this article, the authors describe the presentation, evaluation, and management of patients who have retroperitoneal sarcoma.

Management of extremity soft tissue sarcomas.

This article provides an understanding of the evaluation, staging, and management of patients with extremity soft tissue sarcoma. Although there are straightforward guidelines to the management of patients with extremity soft tissue sarcoma, each patient presents with a unique tumor, and considerations for tumor control, functional outcome, and the toxicity of therapy must be considered. As is true for patients diagnosed with sarcoma at other anatomic sites, a multidisciplinary team approach streamlines care with attention to the complexities and intricacies of choosing and delivering optimal therapy.

Sentinel lymph node biopsy in melanoma.

Sentinel lymph node biopsy (SLNB) for patients with newly diagnosed localized invasive melanoma provides excellent prognostic information and results in improved regional disease control. Prior to the common use of SLNB, regional nodal recurrence was the single most common site of melanoma recurrence, with symptomatic, bulky disease that could be disabling and difficult or impossible to control. With the widespread use of SLNB, regional recurrence of melanoma is much less frequent. Even without clear evidence of improvement in overall survival, the significant and reliable prognostic information and the improved regional control make sentinel node biopsy an important procedure that should be offered routinely to many patients with newly diagnosed melanoma.

Quantification and phenotypic characterization of circulating tumor cells for monitoring response to a preventive HER2/neu vaccine-based immunotherapy for breast cancer: a pilot study.

BACKGROUND: Ongoing cancer vaccine trials are limited by the inability of immunologic assays to monitor clinically relevant surrogates of response. Recent advances in the ability to quantify and phenotype circulating tumor cells (CTCs) in breast cancer patients may lead to a role for CTCs in monitoring response to vaccine-based immunotherapy. METHODS: The CellSearch System (Veridex-LLC, Warren, NJ) was used to enumerate total and HER2/neu+ CTCs in 20 mL of blood from all 16 node-positive (NP) breast cancer patients active in our NP HER2/neu E75 peptide vaccine trial at the initiation of this pilot study. These patients were vaccinated with E75 (1000 microg)/GM-CSF (250 microg) monthly x 6 after completion of multimodality therapy. Mean (+/-SEM) number of CTCs and HER2/neu+ CTCs were compared in unmatched (n = 16) and matched (n = 9) prevaccination and postvaccination cases. RESULTS: CTCs were detected in 14 of 16 (88%) patients (mean: 3.4 +/- 0.2 CTC/20 mL). After vaccination, a reduction in CTC/20 mL (prevaccination 3.9 +/- 1.5 vs postvaccination 0.7 +/- 0.4, P = .077) and HER2/neu+ CTC/20 mL (prevaccination 2.8 +/- 1.0 vs postvaccination 0.5 +/- 0.2, P = .048) was demonstrated. A significant delayed-type hypersensitivity (DTH) response suggesting that vaccination was effective in eliciting a peptide-specific immune response was confirmed (22.3 +/- 4.1 vs 3.0 +/- 2.2 [controls] mm, P < .01). All nine patients followed throughout the vaccination series also showed significant reduction in CTCs (4.8 +/- 1.5 vs 0.3 +/- 0.2, P < .01) and HER2/neu+ CTCs (3.0 +/- 0.9 vs 0.4 +/- 0.2, P = .013). CONCLUSIONS: CTCs are readily demonstrated in posttreatment, clinically disease-free NP breast cancer patients. E75+GM-CSF vaccination appears to reduce the number of CTCs. These data suggest a potential role for this clinically validated CTC assay in assessing response to preventive vaccine-based immunotherapy, and further validation studies are underway.

Assessing serum cytokine profiles in breast cancer patients receiving a HER2/neu vaccine using Luminex technology.

We used the Luminex assay to compare serum cytokine profiles of breast cancer patients (BCa) to healthy controls, node-positive (NP) patients to node-negative (NN), and pre- and post-vaccination serum of BCa vaccinated with a HER2/neu E75 peptide vaccine. Sera from 36 pre- and post-vaccination BCa, (12 NP and 24 NN) and 13 healthy, female donors, were evaluated using Luminex technology. Levels of 22 cytokines consisting of interleukin (IL)-1alpha, -1beta, -2, -4, -5, -6, -7, -8, -10, -12, -13, -15, -17, IFN-gamma, G-CSF, GM-CSF, TNF-alpha, IP-10, MIP-1alpha, RANTES, eotaxin and monocyte chemotactic protein-1 (MCP-1) were assessed. Six of 22 cytokines showed significant differences between BCa and healthy controls. MCP-1, eotaxin, RANTES and GM-CSF levels were significantly elevated in BCa (P<0.009) and IL-1alpha and IL-4 levels were significantly decreased in BCa (P<0.015). Cytokine levels were generally elevated in NN patients compared to NP patients with the exception of eotaxin and IL-13, which were increased in NP patients. Three cytokines, IL-6, MIP-1alpha and G-CSF reached statistical significance (P<0.05). In 34 vaccinated BCa, MCP-1, eotaxin and IL-13 were significantly elevated post-vaccination with MCP-1 demonstrating the most significant response (median, 145.8-217.0 pg/ml, P=0.003). Using a multiplex assay we found significant differences in cytokine levels in sera of BCa compared to healthy controls, in NN compared to NP patients, and in vaccinated patients. Our results support an extended analysis of serum cytokine profiles for the potential development of predictive panels in diagnosis, staging and monitoring cancer vaccine trials.

Correlations between serum monocyte chemotactic protein-1 levels, clinical prognostic factors, and HER-2/neu vaccine-related immunity in breast cancer patients.

PURPOSE: We studied serum monocyte chemotactic protein-1 (MCP-1) levels in breast cancer patients in relationship to their clinicopathologic variables and immune response to a /neu E75 vaccine. EXPERIMENTAL DESIGN: We measured MCP-1 levels in 32 /neu(+) breast cancer patients before and after vaccination with a /neu E75 peptide + granulocyte macrophage colony-stimulating factor vaccine. Clinical prognostic variables were collected. Vaccine-specific immunologic responses were monitored. RESULTS: Serum MCP-1 levels >250 pg/mL (MCP-high) correlated with favorable prognostic variables. MCP-high patients compared with MCP-low (<250 pg/mL) patients showed statistically significant later onset of disease, earlier stage of disease, fewer nodal metastasis, and less chemotherapy. MCP-high patients had increased levels of preexisting immunity when compared with MCP-low patients (69% versus 21%; P = 0.02). However, MCP-low patients showed higher inducible levels of MCP-1 compared with MCP-high patients (median increase, 41% versus 0%; P = 0.001) after vaccination. Moreover, MCP-low patients with >50% increase in MCP-1 levels (response-high) had worse clinical prognostic variables compared with patients with <50% increase (response-low). Response-high patients had statistically significant more poorly differentiated tumors, later stage of disease, and higher percentage of large tumors. Patients with >30% postvaccination MCP-1 increase also showed significant increases in E75-specific CD8(+) T-cells (0.05% versus 0.38%; P = 0.03) in response to vaccination. CONCLUSIONS: High serum MCP-1 levels in breast cancer patients correlate with favorable prognostic variables and increased preexisting /neu immunity. E75 vaccination induces the largest MCP-1 response in patients with unfavorable clinicopathologic variables. Therefore, low serum MCP-1 levels may identify patients with worse prognosis and those most likely to benefit from this vaccination.

The anatomy of the TNM for colon cancer.

BACKGROUND: To visualize the anatomy as revealed by dendrograms of the tumor, lymph node, and metastasis (TNM) staging system for colon cancer and compare it with the Dukes' system. METHODS: A hierarchical clustering algorithm generated tree-structured dendrograms that stratified patients according to survival only. The dendrograms were constructed with the same prognostic variables used for the TNM. Because combinations of prognostic factors were stratified only on survival, additional factors of any number and type could be integrated into the TNM without changing the TNM categories. RESULTS: The algorithm provided a step-by-step visualization of the TNM and the Dukes' system for colon cancer. Dendrograms and associated 5-year survival rates were generated for the T category only, the N category only, the T, N combination, and combinations of the T, N, and M, and the T, N, M with histological grade. Dendrograms revealed visual differences between the structure of TNM and the Dukes' system of staging. Dendrograms also revealed how variations in prognostic factors changed survival. By cutting dendrograms along their dissimilarity axis, multiple prognostic subgroups could be created for colon cancer that may reflect outcomes that are more accurate to estimate. CONCLUSIONS: Dendrograms provide a new way to view cancer patient staging. They reveal a visual step-by-step hierarchical relationship between survival rates and combinations of prognostic variables. The dendrograms also revealed fundamental differences between the TNM and the Dukes system of staging. By stratifying on survival only, additional factors including molecular factors can be added to the TNM, because it classifies patients according to survival rates only and not according to pre-set rules of prognostic factors and stage groups. The clinical implications of stratifying only survival are discussed.

Nonsteroidal anti-inflammatory drugs may affect cytokine response and benefit healing of combat-related extremity wounds.

BACKGROUND: After adequate operative debridement and antimicrobial therapies, combat-related extremity wounds that either heal or fail are both associated with a distinct inflammatory response. Short-term use of nonsteroidal anti-inflammatory drugs in postoperative pain management may affect this response and, by consequence, the healing potential of these wounds. We investigated whether patients treated with nonsteroidal anti-inflammatory drugs had a distinct inflammatory response; different rates of critical colonization, defined as >105 colony forming units on quantitative bacteriology; and healing potential. METHODS: We retrospectively reviewed the records of 73 patients with combat-related extremity wounds. Patients were separated into 2 groups: those who received nonsteroidal anti-inflammatory drugs during the debridement period (nonsteroidal anti-inflammatory drugs group, N = 17) and those who did not (control group; N = 56). Serum and wound tissue samples collected during each operative debridement were measured for 32 known cytokines and tested for quantitative bacteriology, respectively. We compared cytokine concentrations between groups and then designed a logistic regression model to identify variables associated with successful wound healing, while controlling for known confounders. RESULTS: Despite similar demographics and wound characteristics, the nonsteroidal anti-inflammatory drugs group had significant lesser concentrations of inflammatory cytokines, interleukin-2, interleukin-6, interleukin-8, and monocyte chemoattractant protein-1. On multivariate analysis, nonsteroidal anti-inflammatory drug treatment emerged as a predictor of successful wound healing after controlling for known confounders such as wound size, tobacco use, Acute Physiology and Chronic Health Evaluation II score, and critical colonization. CONCLUSION: Treatment with nonsteroidal anti-inflammatory drugs for postoperative pain management after major combat-related extremity trauma is associated with lesser concentrations of inflammatory cytokines and may contribute to a more favorable inflammatory response leading to successful wound healing.