In-Theater Management of Vascular Injury: 2 Years of the Balad Vascular Registry

BACKGROUND

Wartime vascular injury management has traditionally advanced vascular surgery. Despite past military experience, and recent civilian publications, there are no reports detailing current in-theater treatment. The objective of this analysis is to describe the management of vascular injury at the central echelon III surgical facility in Iraq, and to place this experience in perspective with past conflicts.

STUDY DESIGN

Vascular injuries evaluated at our facility between September 1, 2004 and August 31, 2006 were prospectively entered into a registry and reviewed.

RESULTS

During this 24-month period, 6,801 battle-related casualties were assessed. Three hundred twenty-four (4.8%) were diagnosed with 347 vascular injuries. Extremity injuries accounted for 260 (74.9%). Vascular injuries in the neck (n = 56; 16.1%) and thoracoabdominal domain (n = 31; 8.9%) were less common. US forces accounted for 149 casualties (46%), 97 (30%) were local civilian, and 78 (24%) were Iraqi forces. One hundred seven (33%) patients with vascular injury were evacuated from forward locations after treatment initiation. Fifty-four (50%) of these had temporary shunts placed. Of 43 proximal shunts placed in-field, 37 (86%) were patent at the time of our assessment. Early amputation rate was 6.6% for those extremity injuries treated for limb salvage. Perioperative mortality was 4.3%.

CONCLUSIONS

This evaluation represents the first in-theater report of wartime vascular injury since Vietnam. Extremity injuries continue to predominate, although the incidence of vascular injury appears to be somewhat increased. Local forces and civilians now represent a substantial proportion of those injured. The principles of rapid evacuation, temporary shunting, and early reconstruction are effective, with satisfactory early in-theater limb salvage.

The complete management of extremity vascular injury in a local population: A wartime report from the 332nd Expeditionary Medical Group/Air Force Theater Hospital, Balad Air Base, Iraq

BACKGROUND

Although the management of vascular injury in coalition forces during Operation Iraqi Freedom has been described, there are no reports on the in-theater treatment of wartime vascular injury in the local population. This study reports the complete management of extremity vascular injury in a local wartime population and illustrates the unique aspects of this cohort and management strategy.

METHODS

From September 1, 2004, to August 31, 2006, all vascular injuries treated at the Air Force Theater Hospital (AFTH) in Balad, Iraq, were registered. Those in noncoalition troops were identified and retrospectively reviewed.

RESULTS

During the study period, 192 major vascular injuries were treated in the local population in the following distribution: extremity 70% (n=134), neck and great vessel 17% (n=33), and thoracoabdominal 13% (n=25). For the extremity cohort, the age range was 4 to 68 years and included 12 pediatric injuries. Autologous vein was the conduit of choice for these vascular reconstructions. A strict wound management strategy providing repeat operative washout and application of the closed negative pressure adjunct was used. Delayed primary closure or secondary coverage with a split-thickness skin graft was required in 57% of extremity wounds. All patients in this cohort remained at the theater hospital through definitive wound healing, with an average length of stay of 15 days (median 11 days). Patients required an average of 3.3 operations (median 3) from the initial injury to definitive wound closure. Major complications in extremity vascular patients, including mortality, were present in 15.7% (n=21). Surgical wound infection occurred in 3.7% (n=5), and acute anastomotic disruption in 3% (n=4). Graft thrombosis occurred in 4.5% (n=6), and early amputation and mortality rates during the study period were 3.0% (n=4) and 1.5% (n=2), respectively.

CONCLUSIONS

To our knowledge, this study represents the first large report of wartime extremity vascular injury management in a local population. These injuries present unique challenges related to complex wounds that require their complete management to occur in-theater. Vascular reconstruction using vein, combined with a strict wound management strategy, results in successful limb salvage with remarkably low infection, amputation and mortality rates.

Delayed evaluation of combat-related penetrating neck trauma

OBJECTIVE

The approach to penetrating trauma of the head and neck has undergone significant evolution and offers unique challenges during wartime. Military munitions produce complex injury patterns that challenge conventional diagnosis and management. Mass casualties may not allow for routine exploration of all stable cervical blast injuries. The objective of this study was to review the delayed evaluation of combat-related penetrating neck trauma in patients after evacuation to the United States.

METHOD

From February 2003 through April 2005, a series of patients with military-associated penetrating cervical trauma were evacuated to a single institution, prospectively entered into a database, and retrospectively reviewed.

RESULTS

Suspected vascular injury from penetrating neck trauma occurred in 63 patients. Injuries were to zone II in 33%, zone III in 33%, and zone I in 11%. The remaining injuries involved multiple zones, including the lower face or posterior neck. Explosive devices wounded 50 patients (79%), 13 (21%) had high-velocity gunshot wounds, and 19 (30%) had associated intracranial or cervical spine injury. Of the 39 patients (62%) who underwent emergent neck exploration in Iraq or Afghanistan, 21 had 24 injuries requiring ligation (18), vein interposition or primary repair (4), polytetrafluoroethylene (PTFE) graft interposition (1), or patch angioplasty (1). Injuries occurred to the carotid, vertebral, or innominate arteries, or the jugular vein. After evacuation to the United States, all patients underwent radiologic evaluation of the head and neck vasculature. Computed tomography angiography was performed in 45 patients (71%), including six zone II injuries without prior exploration. Forty (63%) underwent diagnostic arteriography that detected pseudoaneurysms (5) or occlusions (8) of the carotid and vertebral arteries. No occult venous injuries were noted. Delayed evaluation resulted in the detection of 12 additional occult injuries and one graft thrombosis in 11 patients. Management included observation (5), vein or PTFE graft repair (3), coil embolization (2), or ligation (1).

CONCLUSIONS

Penetrating multiple fragment injury to the head and neck is common during wartime. Computed tomography angiography is useful in the delayed evaluation of stable patients, but retained fragments produce suboptimal imaging in the zone of injury. Arteriography remains the imaging study of choice to evaluate for cervical vascular trauma, and its use should be liberalized for combat injuries. Stable injuries may not require immediate neck exploration; however, the high prevalence of occult injuries discovered in this review underscores the need for a complete re-evaluation upon return to the United States.

The Management of Trauma Venous Injury: Civilian and Wartime Experiences

The management of venous trauma continues to be debated. Historically, ligation of injured veins is the most common modality of surgical treatment. In the past half-century, additional techniques have been used, including primary repair, interposition graft, and occasionally endovascular techniques. Venous repair, whether in the acute or chronic setting, is believed to prevent or ameliorate the complications of pain, edema, and phlegmasia. Venous repair in civilian trauma and in wartime is commonplace; however, overall treatment strategies remain largely unchanged since the Vietnam War.

The impact of intraoperative shunting on early neurologic outcomes after carotid endarterectomy

BACKGROUND

Although the need for intraoperative shunting during carotid endarterectomy (CEA) is intensely debated, relatively few studies have compared the neurologic outcomes of patients undergoing CEA with or without shunts. The objective of our analysis was to determine the impact of intraoperative shunting during CEA on the incidence of postoperative stroke.

METHODS

The 2012 CEA-targeted American College of Surgeons National Surgical Quality Improvement Program database was used for this analysis. The preoperative and operative characteristics of patients undergoing CEA with or without intraoperative shunting were compared. From this overall sample, propensity score techniques were then used to match patients with or without intraoperative shunting for a number of variables, including age, degree of ipsilateral and contralateral carotid stenosis, presence of several anatomic or physiologic risk factors, anesthesia modality, and use of patch angioplasty vs primary arteriotomy closure. The 30-day postoperative mortality and combined stroke/transient ischemic attack (TIA) rates of this matched cohort were then compared. A similar analysis was also performed on a subgroup of patients with severe stenosis or occlusion of the contralateral carotid artery.

RESULTS

A total of 3153 patients were included for initial analysis (2023 "no-shunt" patients vs 1130 "shunt" patients). From this overall sample, propensity score matching yielded a cohort of 1072 patients with or without intraoperative shunt placement who were well matched for all known patient- and procedure-related factors. There was no significant difference in the incidence of postoperative stroke/TIA between the two groups of this matched cohort (3.4% in the no-shunt group vs 3.7% in the shunt group; P = .64). Analysis of a similarly well matched subgroup of patients with severe stenosis or occlusion of the contralateral carotid artery demonstrated a statistically nonsignificant increase in the incidence of postoperative stroke/TIA with the use of intraoperative shunting (4.9% in the no-shunt group vs 9.8% in the shunt group; P = .08).

CONCLUSIONS

There is no clinical benefit to intraoperative shunting during CEA, even in patients who may be at high risk for intraoperative cerebral hypoperfusion due to severe stenosis or occlusion of the contralateral carotid artery.

Intravascular Ultrasound—Guided Inferior Vena Cava Filter Placement in the Military Multitrauma Patients: A Single-Center Experience

Background: High velocity fragments have resulted in a multitude of complex injuries in the military patients, placing them at increased risk of venous thromboembolism. Methods: A retrospective analysis was performed of all the intravascular ultrasound (IVUS)-guided bedside inferior vena cava (IVC) filters placed between August 2003 and October 2007. Results: Fourteen patients had bedside IVUS-guided retrievable filter placement. Thirteen males and one female and the mean (+SD) injury severity scores (ISS) was 37.2 (+9.9). The most common causes of injury were explosive devices (57%), gunshot wounds (28%), rocket-propelled grenades (7%), and motor vehicle crashes (7%). Indications for filter insertion were deep venous thrombosis in 36% of patients and pulmonary embolus in 28%. Thirty five percent had filters inserted prophylactically. Conclusions: Military trauma population ISS is considerably higher than what is reported in the civilian population. The bedside IVUS-guided IVC filter insertion is particularly useful in this population.

Estrogen blocks homocysteine-induced endothelial dysfunction in porcine coronary arteries1,2

BACKGROUND

The objective of this study was to examine the effect of estrogen combined with homocysteine on vasomotor function and endothelial integrity in intact porcine coronary arteries.

MATERIALS AND METHODS

Pig coronary artery rings were incubated with estrogen, homocysteine, or estrogen and homocysteine for 24 h. Myographic analysis was performed with thromboxane A2 analog U46619 for contraction and bradykinin or sodium nitroprusside for relaxation. Endothelial nitric oxide synthase (eNOS) levels were determined by immunohistochemistry. Levels of superoxide anion were assessed by lucigenin-enhanced chemiluminescence analysis.

RESULTS

Endothelium-dependent vasorelaxation (bradykinin) for the homocysteine alone group was 62% compared with control (P < 0.05), and endothelium-dependent vasorelaxation for the estrogen alone group was 85% compared with control (P > 0.05). Endothelium-dependent vasorelaxation for the estrogen-homocysteine combined group was 79% compared with 89% for control (P > 0.05). There were no differences in endothelium-independent vasorelaxation (sodium nitroprusside) or in smooth muscle contractility (U46619) between all three groups and control. In addition, the eNOS immunoreactivity was declined in the homocysteine group and had no major change in the estrogen or estrogen plus homocysteine-treated group as compared with controls. The superoxide free radical measurement showed a marked increase in the homocysteine group, no major change from controls in the estrogen group, and a much-lessened effect in the combination of estrogen and homocysteine.

CONCLUSIONS

These data demonstrate that combining estrogen with homocysteine significantly blocks the effect of homocysteine on impairing endothelium-dependent vasorelaxation as well as on decreasing eNOS expression and increasing oxidative stress in porcine coronary arteries. This study suggests that estrogen may play a role in preventing homocysteine-mediated endothelial dysfunction and may be of benefit in the hyperhomocysteinemic patient.

Effects of progesterone and estrogen on endothelial dysfunction in porcine coronary arteries

BACKGROUND

The effects of hormone replacement therapy (HRT) on the vascular endothelium have been controversial. In this study, we determined the effects of HRT on endothelium-dependent relaxation in a porcine coronary artery model.

METHODS

Coronary artery rings harvested from female swine were incubated as controls or with estrogen (10(-9), 10(-8), 10(-7) g/L), progesterone (1 x 10(-6), 1 x 10(-5), 5 x 10(-5) g/L), or a combination of the two (10(-8)g/L estrogen, 1 x 10(-5)g/L progesterone). After 24 h in tissue culture, the rings were tested on a myograph system to measure contraction and endothelium-dependent relaxation. Myograph analysis was performed with the thromboxane A2 analogue U46619 for contraction and bradykinin or sodium nitroprusside for relaxation. Nitric oxide synthase (eNOS) levels were determined by immunohistochemistry. Levels of superoxide anion in the progesterone or estrogen treated tissues were assessed by lucigenin-enhanced chemiluminescence analysis.

RESULTS

In response to 10(-7)M bradykinin, porcine coronary artery rings treated with 1 x 10(-6), 1 x 10(-5) and 5 x 10(-5) g/L of progesterone showed a significant reduction in endothelium-dependent vasorelaxation by 36%, 45%, and 68%, respectively, as compared to controls (P <0.05). However, rings treated with estrogen showed no significant difference as compared to controls. Furthermore, estrogen treatment with progesterone reversed the effect of progesterone, showing no difference in vessel relaxation as compared to controls. There were no differences in endothelium-independent vasorelaxation (sodium nitroprusside) or in smooth muscle contractility (U46619) between the control and the hormone-treated groups. The eNOS immunoreactivity was reduced in progesterone-treated coronary artery rings. Furthermore, coronary endothelium exposed to progesterone showed a 59% increase in superoxide anion production, while estrogen produced a 67% decrease when compared to controls (P <0.05 for both).

CONCLUSION

This data suggests that the progesterone component of HRT has a detrimental influence on endothelium-dependent relaxation. This effect appears to be related to decreased eNOS levels, as well as increased consumption of NO by superoxide anion in the endothelium of tissues exposed to progesterone. Estrogen can block progesterone-induced endothelial dysfunction and superoxide anion production in the pig coronary artery model.

National Study of Internal Medicine Manpower: X. Internal medicine residency and fellowship training: 1985 update

The number of medical school graduates entering internal medicine residency training was at an all-time high in 1984-85. Although the number of first-year residents who were foreign-trained physicians did not differ greatly from the 1983-84 census, the number of first-year residents who were U.S. medical school graduates was much higher than the previous year largely because the number of graduates from U.S. medical schools increased substantially in 1984. The number of internal medicine fellowship programs and the number of fellows in 1984-85 were also at an all-time high. Foreign-trained physicians represent 22% of those in residency training and 20% of those in fellowship training. Of every 100 who completed residency training, 61 went on to a first year of subspecialty fellowship training, a number up slightly from the previous year. The increasing numbers of residents and fellows being trained in internal medicine, combined with the preference for subspecialization and the substantial proportion of foreign-trained physicians being trained, are discussed against the background of pending legislation to reduce federal assistance for graduate medical education.

A modern approach to cervical vascular trauma

Blunt or penetrating trauma to the major arteries of the neck are challenging problems, however, newer diagnostic and therapeutic modalities have simplified care and largely eliminated the need for diagnostic neck exploration. High-quality computed tomographic angiography is quick and sensitive, identifying the vast majority of injuries prior to any operative intervention. Even in cases where active exsanguination or impending airway compromise mandates immediate exploration, intraoperative imaging and endovascular interventions have largely supplanted relatively morbid exposures for open repair. Traditional open repair of carotid injuries with primary closure or interposition grafting is effective over the long term and is always recommended if proximal and distal control can be achieved in a safe and straightforward manner. Endovascular repair of the proximal carotid, proximal subclavian, and distal internal carotid arteries is increasingly accepted. However, vertebral trauma is dealt with almost exclusively by endovascular means. Recent military experiences in Iraq and Afghanistan highlight the imaging-intensive management of cervical vascular trauma and demonstrate the effectiveness of computed tomography angiography, selective arteriography, and endovascular interventions.

Reversal of transjugular intrahepatic portosystemic shunt (TIPS)-induced hepatic encephalopathy using a strictured self-expanding covered stent

Hepatic encephalopathy is a known complication following percutaneous transjugular intrahepatic portosystemic shunt (TIPS) placement. We describe herein a simple and effective strategy of TIPS revision by creating an intraluminal stricture within a self-expanding covered stent, which is deployed in the portosystemic shunt to reduce the TIPS blood flow. This technique was successful in reversing a TIPS-induced hepatic encephalopathy in our patient.

National Study of Internal Medicine Manpower: XI. Internal medicine residency and fellowship training in the 1980s

The number of residents beginning training in internal medicine continued to increase slightly in 1985-86. However, the total number of residents in internal residency training decreased slightly from the previous year due to a decrease in the number of second- and third-year residents. The proportion of first-year residents who were foreign-trained physicians decreased from 21% to 20%, and the proportion of residents who finished training and went on to subspecialty training in 1985 decreased substantially to 56%. The number of physicians entering residency and fellowship training in internal medicine considerably exceeds the number projected by the Graduate Medical Education National Advisory Committee. In this article, we discuss implications of these trends for medical education and practice.

Upper extremity arterial combat injury management

Traumatic hemorrhage and vascular injury management have been concerns for both civilian and military physicians. During the 20th century, advances in technique allowed surgeons to focus on vascular repair, restoration of perfusion, limb salvage, and life preservation. Military surgeons such as Makins, DeBakey, Hughes, Rich, and others made significant contributions to the field of surgery in general and vascular surgery in particular. Casualties from combat in Afghanistan and Iraq confront physicians and surgeons with devastating injuries. The current generation of providers is challenged with applying contemporary care while expanding upon the lessons taught by our predecessors. The objective of this report is to review the historical experience with managing military upper extremity arterial injuries and compare that experience with current management.

Restoring venous patency with the ClotTriever following deep vein thrombosis

OBJECTIVE

Though randomized data remains inconclusive, invasive endovenous therapy is increasingly favored in patients with extensive iliocaval or iliofemoral deep venous thrombosis (DVT) to reduce rates of post-thrombotic syndrome (PTS). Previously, pharmacomechanical thrombectomy was the therapy of choice, but the Inari ClotTriever device (Inari Medical, Irvine, California) is an appealing, purely mechanical, alternative. It may reduce bleeding risk, ICU admission, and the need for multiple procedures, when compared to traditional thrombolysis. We present a series of eighteen patients treated with the ClotTriever for extensive iliocaval or iliofemoral DVT.

METHODS

The Inari ClotTriever is a percutaneous mechanical thrombectomy system consisting of an expandable nitinol collection bag that is dragged along the vein wall, separating and capturing thrombus for collection into the retrieval sheath. We retrospectively reviewed all patients undergoing ClotTriever thrombectomy since the device became available at our quaternary referral center in June 2019. Review of these patients' records was determined to be exempt by our institutional IRB.

RESULTS

Eighteen patients underwent ClotTriever thrombectomy between June 2019 and November 2021. The majority of patients (N=16, 89%) presented within 2 weeks of symptom onset, and identifiable provoking factors were present in all patients. The most common provoking factor was anatomy, with May-Thurner Syndrome present in 8 patients. All patients had restoration of unimpeded venous flow in the treated segments, though three had some residual non-flow limiting thrombus. There were no bleeding events or repeat venous procedures. Median post-procedure length of stay of 2 days. Postoperative venous imaging was performed in 15 patients and showed patency of the treated segment in 14 patients. Revised Clinical Venous Severity Scores were available in 14 patients during the course of follow-up. Of these, nine patients' highest scores were 0, two patients' highest scores were 2, two patients' highest scores were 4, and one patient had a high score of 8.

CONCLUSIONS

Venous flow was re-established in all 18 patients treated with the ClotTriever in this series, with no bleeding complications, and median post-procedure length of stay of 2 days. All patients with available follow-up, except 1, retained patency of the treated venous segments and most had mild post-thrombotic syndrome or none at all. These findings suggest that the ClotTriever is a safe and effective way to treat extensive iliocaval/femoral DVT.

Using a population-based registry to identify patterns of care in childhood cancer in Florida

BACKGROUND

Unlike cancers occurring in adults, childhood cancers are distinguished by being primarily nonepithelial in origin and by their relative rarity. Even with the availability of registries such as the Surveillance, Epidemiology and End Results program of the National Cancer Institute or the Florida Cancer Data System for the State of Florida, there are potential biases that may affect the estimates of pediatric cancer incidence, studies related to elucidating patterns of care, and other epidemiologic studies.

METHODS

To evaluate the magnitude of these potential biases and elucidate the settings (pediatric cancer center versus non-cancer center) in which childhood cancers are treated, the authors performed a retrospective study of childhood cancer in Florida.

RESULTS

Approximately 19% of childhood cancer cases (in patients 0-19 years of age) in Florida diagnosed from 1981 to 1986 were treated outside of identified pediatric cancer centers in the state. Children with Hodgkin disease and brain tumors represented 43% of these cases. Among those cases treated in pediatric cancer centers, 23% were treated by physicians other than pediatric oncologists. Children with brain tumors represented 28% of these cases. Of those treated by pediatric oncologists, 65% were eligible for a cooperative group protocol and 55% of these were enrolled.

CONCLUSIONS

Population-based registries are necessary for describing the full extent of childhood cancer, but they have limitations in demonstrating patterns of care. Consequently, generalization from the experience of pediatric cancer centers is questionable, and the opportunity to test and achieve advances in diagnosis and treatment may be subject to selection bias.

Simultaneous transcarotid artery revascularization with flow reversal and coronary artery bypass grafting: A novel hybrid technique

Optimal management of concomitant coronary artery disease and carotid artery stenosis remains unknown. Current treatment strategies for patients with significant dual disease burden include simultaneous carotid endarterectomy and coronary artery bypass grafting (CABG) or staged carotid endarterectomy and CABG. Herein we present the case of a patient with severe coronary artery disease and carotid artery stenosis and discuss a novel hybrid approach to management of concomitant coronary and carotid disease using transcarotid artery revascularization with flow reversal before CABG.

The incidence of pediatric cancer in Florida, 1981 to 1986

Incidence rates for pediatric (ages, 0 to 14 years) cancer in the state of Florida were produced for the period 1981 to 1986 and compared with national data to investigate variations in pediatric cancer incidence. Overall, Florida had an incidence rate of 12.77 per 100,000; this was not significantly higher than expected based on national rates (standardized incidence ratio, 1.0; 95% confidence interval, 0.9 to 1.0). Compared with national rates, whites residing in Florida had an increased rate of acute lymphocytic leukemia and decreased rate for soft tissue sarcomas (other than rhabdomyosarcoma), "other leukemias," and "other" cancers. Nonwhites residing in Florida had increased rates for soft tissue sarcomas (other than rhabdomyosarcoma) and decreased rates of "other" cancers. Boys in Florida had increased rates for retinoblastoma and acute lymphocytic leukemia and decreased rates for "other leukemias" and "other" cancers. Rates for girls were decreased for neuroblastoma and "other leukemias."

Spliced arm vein grafts are a durable conduit for lower extremity bypass

BACKGROUND

Many patients with peripheral vascular disease (PAD) requiring revascularization do not have adequate ipsilateral great saphenous vein (GSV) for constructing a bypass because of intrinsic vein disease or prior harvesting for limb or coronary bypass. Prosthetic conduits have poor long-term patency, especially for distal bypass. With advancing endovascular sophistication, tibial angioplasty may be a good revascularization option, but we hypothesize that using spliced arm vein for distal lower extremity bypass is still a well-tolerated and more durable solution.

METHODS

A retrospective chart review was conducted of all PAD patients undergoing lower extremity bypass or tibial angioplasty for lifestyle-limiting claudication or critical limb ischemia at a single institution over a 7-year period. Statistical analysis was conducted by Kaplan-Meier survival analysis and Cox proportional hazards model. Statistical significance was set at P = 0.05.

RESULTS

From 2005 to 2012, there were 120 patients who underwent infrageniculate revascularization with conduit other than GSV. Over half of the patients (66 patients, 71.2% male, mean age 62 years) underwent bypass operations using arm vein conduit, and 88% of those bypasses were to tibial vessels. Patency was 100% at 1 year and 85% at 2 years. There was no impact on patency or amputation rate based on the source of vein or the number of splices. Forty-three patients underwent tibial angioplasty and patency was 70% at 1 year and 50% at 2 years.

CONCLUSIONS

When GSV is not available, spliced arm vein grafts provide durable lower extremity revascularization with favorable patency and limb preservation rates. Spliced arm vein grafts should be considered over prosthetic grafts and angioplasty alone in patients with distal occlusive disease.

Socioeconomic and demographic factors that predict where children receive cancer care in Florida

Socioeconomic and demographic factors associated with type of facility (cancer center vs non-cancer center) at which a child with cancer is seen were identified to suggest interventions to increase access to state-of-the-art care. The 2268 children with cancer in Florida (1981-1986) were classified as ever having been seen or not having been seen at a cancer center. Patients referred from one type of facility to another were compared to those not referred. Nineteen percent of children with cancer were never seen at a cancer center. These children were likely to be older (15-19 years of age), have Hodgkin's disease or a brain tumor, reside in a county without a cancer center, or have higher median income. Interventions extending state-of-the-art cancer care beyond cancer centers should target (1) physicians treating adolescent-aged children and (2) patients for whom private insurance may serve as a barrier to referral and protocol therapy.