Multidisciplinary Recommendations Regarding Post-Vaccine Adenopathy and Radiologic Imaging: Radiology Scientific Expert Panel.

Vaccination-associated adenopathy is a frequent imaging finding after administration of COVID-19 vaccines that may lead to a diagnostic conundrum in patients with manifest or suspected cancer, in whom it may be indistinguishable from malignant nodal involvement. To help the medical community address this concern in the absence of studies and evidence-based guidelines, this special report offers recommendations developed by a multidisciplinary panel of experts from three of the leading tertiary care cancer centers in the United States. According to these recommendations, some routine imaging examinations, such as those for screening, should be scheduled before or at least 6 weeks after the final vaccination dose to allow for any reactive adenopathy to resolve. However, there should be no delay of other clinically indicated imaging (eg, for acute symptoms, short-interval treatment monitoring, urgent treatment planning or complications) due to prior vaccination. The vaccine should be administered on the side contralateral to the primary or suspected cancer, and both doses should be administered in the same arm. Vaccination information-date(s) administered, injection site(s), laterality, and type of vaccine-should be included in every preimaging patient questionnaire, and this information should be made readily available to interpreting radiologists. Clear and effective communication between patients, radiologists, referring physician teams, and the general public should be considered of the highest priority when managing adenopathy in the setting of COVID-19 vaccination.

Comprehensive Complication Index Validates Improved Outcomes Over Time Despite Increased Complexity in 3707 Consecutive Hepatectomies.

OBJECTIVE: The aim of this study was to evaluate trends over time in perioperative outcomes for patients undergoing hepatectomy. BACKGROUND: As perioperative care and surgical technique for hepatectomy have improved, the indications for and complexity of liver resections have evolved. However, the resulting effect on the short-term outcomes over time has not been well described. METHODS: Consecutive patients undergoing hepatectomy during 1998 to 2015 at 1 institution were analyzed. Perioperative outcomes, including the comprehensive complication index (CCI), were compared between patients who underwent hepatectomy in the eras 1998 to 2003, 2004 to 2009, and 2010 to 2015. RESULTS: The study included 3707 hepatic resections. The number of hepatectomies increased in each era (794 in 1998 to 2003, 1402 in 2004 to 2009, and 1511 in 2010 to 2015). Technical complexity increased over time as evidenced by increases in the rates of major hepatectomy (20%, 23%, 30%, P < 0.0001), 2-stage hepatectomy (0%, 3%, 4%, P < 0.001), need for portal vein embolization (5%, 9%, 9%, P = 0.001), preoperative chemotherapy for colorectal liver metastases (70%, 82%, 89%, P < 0.001) and median operative time (180, 175, 225 minutes, P < 0.001). Significant decreases over time were observed in median blood loss (300, 250, 200 mL, P < 0.001), transfusion rate (19%, 15%, 5%, P < 0.001), median length of hospitalization (7, 7, 6 days, P < 0.001), rates of CCI ≥26.2 (20%, 22%, 16%, P < 0.001) and 90-day mortality (3.1%, 2.6%, 1.3%, P < 0.01). On multivariable analysis, hepatectomy in the most recent era 2010 to 2015 was associated with a lower incidence of CCI ≥26.2 (odds ratio 0.7, 95% confidence interval 0.6-0.8, P < 0.0001). CONCLUSION: Despite increases in complexity over an 18-year period, continued improvements in surgical technique and perioperative outcomes yielded a resultant decrease in CCI in the most current era.

Outcomes of research biopsies in phase I clinical trials: the MD anderson cancer center experience.

BACKGROUND: Research biopsies are crucial for exploring the impact of novel agents on putative targets. The current study assesses the safety and success rate associated with performing such biopsies. METHODS: We reviewed the medical records of 155 consecutive patients who had one or more research biopsies as part of a phase I trial from September 2004 to October 2009. RESULTS: Of 281 research biopsies performed, 118 were paired before and after treatment biopsies (total = 236 biopsies). The most common sites of biopsy were superficial lymph node (19.9%), followed by liver (16.4%), and then soft tissue (15.7%). Ultrasound-guided biopsies were the most frequent type (53.7%). Among 142 patients who consented for mandatory biopsy, 86.6% had the biopsy performed, compared with 4.4% of 911 patients offered a biopsy on an optional basis (p < .0001). Biopsy was obtained most frequently on industry-sponsored trials; lack of funding on nonindustry trials was the most common reason that biopsies were not obtained. Of 281 single biopsies, only 4 (1.4%) had complications: pneumothorax requiring chest tube placement (n = 2), infection requiring admission (n = 1), and arrhythmia with hypotension (n = 1). All but one biopsy was successful in obtaining tissue. No deaths were attributable to biopsy. CONCLUSIONS: Our experience demonstrates that research biopsies in early phase clinical trials are safe (1.4% risk of serious complications), and a higher percentage of patients underwent mandatory biopsies (86.6%) compared with that of the patients with optional biopsies (4.4%).

Air travel after biopsy-related pneumothorax: is it safe to fly?

PURPOSE: To evaluate the safety of air travel after percutaneous transthoracic needle biopsy (PTNB). MATERIALS AND METHODS: The study population included 179 patients who underwent 183 PTNBs followed by air travel within 14 days of the procedure. Patients were contacted after their flight and asked to complete a brief telephone survey that assessed for the development of respiratory symptoms during air travel. RESULTS: No patient reported experiencing an in-flight medical event that required emergent, in-flight medical attention or flight diversion. Postbiopsy pneumothorax developed in 65 patients. Of patients with postbiopsy pneumothorax, including patients with radiographic evidence of residual pneumothorax, 50 (77%) traveled within 4 days of the final postbiopsy chest radiograph. Worsening of existing respiratory symptoms or the development of new respiratory symptoms during or after the flight was reported in 14 of 183 patients (8%). CONCLUSIONS: This study shows that air travel after biopsy-related pneumothorax can occur safely before radiographic resolution of pneumothorax and as soon as 24 hours after PTNB.

Steps toward mapping the human vasculature by phage display.

The molecular diversity of receptors in human blood vessels remains largely unexplored. We developed a selection method in which peptides that home to specific vascular beds are identified after administration of a peptide library. Here we report the first in vivo screening of a peptide library in a patient. We surveyed 47,160 motifs that localized to different organs. This large-scale screening indicates that the tissue distribution of circulating peptides is nonrandom. High-throughput analysis of the motifs revealed similarities to ligands for differentially expressed cell-surface proteins, and a candidate ligand-receptor pair was validated. These data represent a step toward the construction of a molecular map of human vasculature and may have broad implications for the development of targeted therapies.

Early experience using an online reporting system for interventional radiology procedure-related complications integrated with a digital dictation system.

The absence of user-friendly systems for reporting complications is a major barrier to improving quality assurance (QA) programs in interventional radiology (IR) services. We describe the implementation of a QA application that is completely integrated with the radiology dictation system. We implemented an IR QA process as a module within the electronic medical record and radiologist dictation system applications used at our institution. After a radiologist completes a dictation, he or she must select from a drop-down list of complications before proceeding to the next case. Delayed QA events can be entered using the same applications. All complication entries are sent to a database, which is queried to run reports. During the study period, all the 20,034 interventional procedures were entered in the QA database, 1,144 complications were reported, 110 (9.6%) of which were classified as major. Although majority of the complications (996) were entered at the time of dictation, 148 complications (12.9%) were entered afterwards. All major complications were referred to the IR peer review committee, and 30 of these were discussed in the morbidity and mortality meetings. We studied post-lung-biopsy pneumothorax and chest tube rates and initiated a quality improvement process based on the results.The integration of the IR QA reporting system into the workflow process and the mandatory requirements for completion has the potential to minimize the work effort required to enter complication data, and improve participation in the QA process.

CT-guided percutaneous lung biopsies in patients with haematologic malignancies and undiagnosed pulmonary lesions.

We searched the electronic patient database at The University of Texas M. D. Anderson Cancer Center for patients who underwent computed tomography (CT)-guided needle biopsy between January 2001 and December 2005. Inclusion criteria were a known history of haematologic malignancy and a newly detected, undiagnosed pulmonary lesion on chest CT that required tissue sampling for diagnosis; 213 met these criteria. We analysed the biopsy results for diagnostic yield, factors affecting diagnostic yield and effect on treatment. Of 213 procedures, 191 (89.7%) yielded sufficient material for pathologic analysis; 130 (60%) yielded specific diagnoses, while 61 (28.6%) yielded nonspecific benign diagnoses. Lesions larger than 1 cm, cavitary lesions and lung masses were more likely to yield a specific diagnosis than were lesions smaller than 1 cm, lung nodules and consolidations. The most common specific diagnoses were malignancy (62.8%) and infection (34.3%). The latter was more common in patients with leukaemia, cavitary lung lesions or consolidations, active underlying malignancy, neutropenia, respiratory signs and symptoms and/or fever, bone marrow transplant recipients, and in patients receiving chemotherapy. Lung lesions discovered upon follow-up imaging in patients who did not have any respiratory signs/symptoms or fever were mostly malignant. Therapeutic changes were more likely after a specific diagnosis than after a nonspecific diagnosis or a nondiagnostic biopsy (88.4% vs. 18.1%; p < 0.0001). CT-guided lung biopsy has a high diagnostic yield in patients with haematologic malignancies that present with unexplained pulmonary lesions and provides a specific diagnosis in a majority of these patients, leading to therapeutic changes.

Comparison of Real-Time Fluorescence Confocal Digital Microscopy With Hematoxylin-Eosin-Stained Sections of Core-Needle Biopsy Specimens.

Importance: Strategies to procure high-quality core-needle biopsy (CNB) specimens are critical for making basic tissue diagnoses and for ancillary testing. Objectives: To investigate acquisition of fluorescence confocal microscopy (FCM) images of interventional radiology (IR)-guided CNB in real time in the radiology suite and to compare the accuracy of FCM diagnoses with those of hematoxylin-eosin (H&E)-stained CNB sections. Design, Setting, and Participants: In this diagnostic study, FCM imaging of IR-guided CNBs was performed in the radiology suite at a major cancer center for patients with an imaging abnormality from August 1, 2016, to April 30, 2019. The time taken to acquire FCM images and the quality of FCM images based on percentage of interpretable tissue with optimal resolution was recorded. The FCM images were read by 2 pathologists and categorized as nondiagnostic, benign/atypical, or suspicious/malignant; these diagnoses were compared with those made using H&E-stained tissue sections. Cases with discrepant diagnosis were reassessed by the pathologists together for a consensus diagnosis. Data were analyzed from June 3 to July 19, 2019. Interventions: Each IR-guided CNB was stained with 0.6mM acridine orange, subjected to FCM imaging, and then processed to generate H&E-stained sections. Main Outcomes and Measures: Mean time taken for acquisition of FCM images, quality of FCM images based on interpretable percentage of the image, and accuracy of diagnostic categorization based on FCM images compared with H&E-stained sections. Results: A total of 105 patients (57 male [54.3%]; mean [SD] age, 63 [13] years) underwent IR-guided CNBs in a mean (SD) of 7 (2) minutes each. The FCM images showed at least 20% of the tissue with optimal quality in 101 CNB specimens (96.2%). The FCM images were accurately interpreted by the 2 pathologists in 100 of 105 cases (95.2%) (2 false-positive and 3 false-negative) and 90 of 105 cases (85.7%) (6 false-positive and 9 false-negative). A reassessment of 14 discordant diagnoses resulted in consensus diagnoses that were accurate in 101 of 105 cases (96.2%) (1 false-positive and 3 false-negative). Conclusions and Relevance: The ease of acquisition of FCM images of acceptable quality and the high accuracy of the diagnoses suggest that FCM may be useful for rapid evaluation of IR-guided CNBs. This approach warrants further investigation.

Bronchial artery embolization for the management of hemoptysis in oncology patients: utility and prognostic factors.

PURPOSE: To evaluate the utility of bronchial artery embolization (BAE) in the oncology population and determine prognostic factors. MATERIALS AND METHODS: This is a retrospective review of 30 consecutive oncology patients (20 men, 10 women; mean age, 60 years) who were referred for BAE for the management of hemoptysis from 1992 to 2007. RESULTS: The amount of hemoptysis at initial embolization was massive (frank blood >300 mL per 24 hours) in 13 patients (43%), moderate (frank blood <300 mL per 24 hours) in 15 (50%), and trivial (blood-tinged sputum) in two (7%). Eighteen patients (60%) had a primary intrathoracic malignancy, seven (23%) had pulmonary metastases, and five (17%) had no evidence of malignant disease in the lung. The technical success rate, defined as the ability to selectively embolize the abnormal vessel, was 86% (32 of 37 procedures). Clinical response categories and complications were defined according to the guidelines established by the SIR Standards of Practice Committee. The major complication rate was 3%, including one case of spinal cord infarction. BAE provided symptom palliation with an immediate decrease or resolution of bleeding in 24 out of 27 patients (89%). The 30-day mortality rate for this cohort was 30%, and the median survival was 5.5 months. Survival was significantly better in patients with non-tumor-related hemoptysis than in those with tumor-related bleeding (P = .004). There was no significant difference in median survival between patients with massive hemoptysis and those with moderate/mild hemoptysis (P = .81), between patients with an emergent procedure and those with a non-emergent procedure (P = .39), and between patients who had previously undergone radiation therapy and those who had not (P = .4). CONCLUSIONS: BAE is safe and effective for the oncologic patient population. In patients with tumor-related hemoptysis, the prognosis remains poor; however, for the subset of oncology patients whose hemoptysis is not related to malignant disease in the lung, the survival is significantly better.

Factors impacting technical success rate of image-guided intra-arterial therapy in rat orthotopic liver tumor model.

Transcatheter hepatic arterial chemoembolization (TACE) is the current standard of care for intermediate stage hepatocellular carcinoma (HCC) patients. To study the effects of TACE in the tumor immune microenvironment, an immunocompetent rat model is required. The purpose of this study was to determine factors influencing technical success during hepatic arterial catheterization in immunocompetent orthotopic rat liver models. To this end, 91 Sprague-Dawley and eighty-three F344 rats underwent transcatheter hepatic arterial embolization using a transcarotid approach and were divided into a non-tumor-bearing (n = 41) and tumor-bearing (n = 133) groups. Vascular diameters of the hepatic arterial branches were evaluated from angiographic images. Catheterization of the proper hepatic artery (PHA) was achieved in 92% of the tumor-bearing and 68.3% of the non-tumor-bearing rats. We found a strong positive association between the diameter of the PHA and animals' body weight in both groups (P < 0.005), independently of the rat's strain. Results of the logistic regression model predicting a successful catheter placement into the PHA according to the animal's weight indicate that successful PHA catheterization is likely to be achieved in tumor-bearing animals weighing ≥ 250 g and > 308 g in non-tumor-bearing rats, with a sensitivity and specificity of 91.3% and 100.0% and 96.4% and 92.3%, respectively. In conclusion, animal's body weight at the time of catheterization is the principal determinant of technical success for transcatheter arterial embolization. Familiarity with these technical factors during animal selection will improve TACE technical success rates.

Percutaneous biopsy of head and neck lesions with CT guidance: various approaches and relevant anatomic and technical considerations.

Deep-seated head and neck lesions, which traditionally were evaluated by surgical means, are now accessible with less invasive computed tomography-guided percutaneous needle biopsy techniques. Major vessels, the trachea, and osseous structures like the maxilla, mandible, and vertebrae often preclude direct access to these lesions. It is important to understand the anatomy relevant to safe access route planning and the techniques, advantages, and limitations associated with various approaches used for percutaneous biopsy of head and neck lesions. For biopsy of suprahyoid head and neck lesions, including those of the skull base and upper cervical vertebrae, various approaches such as the subzygomatic, retromandibular, paramaxillary, submastoid, transoral, and posterior approaches can be used. Lesions in the infrahyoid portion of the neck and lower cervical vertebrae can be accessed with the anterolateral approach (between the airways and the carotid sheath), posterolateral approach (posterior to the carotid sheath), and direct posterior approach. The location and extent of the lesions and their relationship to adjacent structures influence the choice of the trajectory to use. Careful planning of the procedure and considerable familiarity with head and neck anatomy are necessary for a biopsy that is both precise and safe.

Planned Treatment of Advanced Metastatic Disease with Completion Ablation After Hepatic Resection.

PURPOSE: The aim of this study is to describe a modified treatment strategy with image-guided percutaneous ablation after hepatic resection as a completion method to surgical eradication of liver metastases ("completion ablation [CA]"). METHODS: We conducted a retrospective analyses of patients who underwent CA within 180 days from the liver surgical resection to eradicate liver metastases present on the pre-surgical cross-sectional imaging or identified during intraoperative ultrasound that were not resected due to various reasons. Lesions treated with CA were evaluated for local tumor progression (LTP). Patients were evaluated for hepatic- and overall-recurrence-free survivals (hepatic-RFS and overall-RFS, respectively) and overall survival (OS). RESULTS: Sixteen patients (10 females; median age 55 years, range 28-69) underwent CA of 21 lesions (median size 8 mm, range 6 to 22). Indications for the use of CA were small future liver remnant in 10 (63%), inability to identify the lesion during surgical exploration in 3 (19%), and technical difficulty of resection in 3 (19%) patients. No liver-related complications were recorded following the surgical resection or the CA procedures. Primary and secondary CA efficacy rates were 95 and 100%, respectively. LTP was 0% at a median clinical follow-up of 27 months (range 4.0-108 months). Five-year hepatic-RFS, overall-RFS, and OS were 36, 16, and 51%, respectively. CONCLUSION: The use of CA as a complement to surgical resection is safe and effective. Such approach could potentially expand the surgical candidacy for patients with limited liver functional reserve and reduce postoperative morbidity and mortality in this selected patient population with more advanced disease.

Transthoracic fine-needle aspiration vs concurrent core needle biopsy in diagnosis of intrathoracic lesions: a retrospective comparison of diagnostic accuracy.

To assess the value and limitations of fine-needle aspiration (FNA) and core needle biopsy (CNB) in the diagnosis of intrathoracic lesions, we retrospectively compared the diagnostic accuracy of 362 FNA and concurrent CNB procedures performed on 350 patients. Based on the final diagnoses that were determined based on combined information from biopsy, resection, clinical, radiologic, and microbiologic findings, the study cases were grouped into 188 malignant, 161 benign, and 13 inconclusive lesions. FNA and CNB yielded similar diagnostic accuracy for malignant tumors (85.1% vs 86.7%) and epithelial malignant neoplasms (86.4% vs 85.2%), whereas CNB yielded better diagnostic accuracy (96%) than FNA (77%) for nonepithelial malignant neoplasms. Combined FNA and CNB substantially improved the rate of malignancy diagnosis (95.2%). Of 161 benign cases, 50 were proven to be benign-specific lesions; FNA provided specific diagnosis in 20 (40%) and CNB in 46 (92%). The remaining 111 benign lesions yielded benign-nonspecific findings on both specimens. These results indicate that CNB should be obtained when clinical or radiologic findings do not match the cytologic findings or nonepithelial lesions and benign lesions are considered likely.

Evaluation of targeted arterial delivery of the branched chain fatty acid 12-methyltetradecanoic acid as a novel therapy for solid tumors.

The purpose of this research was to evaluate the effects of targeted arterial delivery of the branched chain fatty acid 12-methyltetradecanoic acid (12-MTA) on the VX2 squamous cell carcinoma in rabbits. An intramuscular VX2 squamous cell carcinoma was induced at a single site in the right thigh of 39 New Zealand white rabbits. Approximately 10 days after inoculation, a 3-French catheter was introduced into the right common carotid artery and positioned using fluoroscopic guidance in the right deep femoral artery, which was the main, if not exclusive, artery supplying the tumor. Ethiodol alone (targeting agent), Ethiodol containing 12-MTA, or Ethiodol containing myristic acid was then injected through the catheter. Tumor growth and histopathology were evaluated 7-8 days after treatment. Caspase-3 activity was evaluated 2 days after therapy, and tumor tissues were assayed for eicosanoid metabolites 2 and 7 days after treatment to assess the effects of the branched chain fatty acid on the lipoxygenase (LOX) and cyclooxygenase-2 (COX-2) enzyme systems. Targeted arterial delivery of 12-MTA resulted in dose-dependent growth inhibition of intramuscular rabbit VX2 tumors while myristic acid, a saturated fatty acid of the same carbon length as 12-MTA, was found to stimulate tumor growth. Two and 7 days following treatment, tumors treated with 12-MTA showed a significant decrease in 5-hydroxyeicosatetraenoic acid (5-HETE) and a concomitant increase in 15-HETE levels while tumors treated with myristic acid exhibited a significant increase in prostaglandin E2 (PGE2) levels. Western blot as well as immunohistochemical analysis showed that 5-LOX and COX-2 proteins were present in the VX2 tumors. No alterations in tumor/tumor cell morphology or caspase-3 activity were evident on microscopic examination following treatment. These studies suggest that targeted arterial delivery of branched chain fatty acids such as 12-MTA may be considered as a potential new therapy for treatment of solid tumors. The exact mechanism(s) responsible for the observed inhibition of VX2 tumor growth by 12-MTA is unclear. Additional in vivo studies are warranted to elucidate 12-MTA's mechanism of action and further investigate the branched chain fatty acid's antitumor effects.

Imaging-guided percutaneous biopsy of mediastinal lesions: different approaches and anatomic considerations.

Percutaneous needle biopsy with imaging guidance allows access to lesions in virtually all mediastinal locations. A direct mediastinal approach, which enables extrapleural needle placement, is the preferred method to avoid the risk of pneumothorax. Techniques that allow extrapleural access include the parasternal, paravertebral, transsternal, and suprasternal approaches, which are performed with computed tomographic or ultrasonographic guidance. The parasternal approach is used for biopsy of anterior or middle mediastinal lesions when the lesion or intervening mediastinal fat extends to the anterior chest wall, lateral to the sternum; injury to the internal mammary vessels is a potential complication. The paravertebral approach is used for biopsy of subcarinal and other posterior mediastinal lesions; saline solution is often injected to widen the mediastinum. The transsternal approach, which involves needle placement through the sternum, is used for biopsy of anterior or middle mediastinal lesions that are not accessible with the parasternal approach. Biopsy of superior mediastinal lesions can be performed with a suprasternal approach. An alternative to these direct mediastinal approaches involves advancing the needle through a pleural space created by an existing pleural effusion or iatrogenic pneumothorax. Another alternative is the transpulmonary approach, which involves transgression of the lung and visceral pleura by the needle and is associated with a substantial risk of pneumothorax.

Splenic arterial interventions: anatomy, indications, technical considerations, and potential complications.

Splenic arterial interventions are increasingly performed to treat various clinical conditions, including abdominal trauma, hypersplenism, splenic arterial aneurysm, portal hypertension, and splenic neoplasm. When clinically appropriate, these procedures may provide an alternative to open surgery. They may help to salvage splenic function in patients with posttraumatic injuries or hypersplenism and to improve hematologic parameters in those who otherwise would be unable to undergo high-dose chemotherapy or immunosuppressive therapy. Splenic arterial interventions also may be performed to exclude splenic artery aneurysms from the parent vessel lumen and prevent aneurysm rupture; to reduce portal pressure and prevent sequelae in patients with portal hypertension; to treat splenic artery steal syndrome and improve liver perfusion in liver transplant recipients; and to administer targeted treatment to areas of neoplastic disease in the splenic parenchyma. As the use of splenic arterial interventions increases in interventional radiology practice, clinicians must be familiar with the splenic vascular anatomy, the indications and contraindications for performing interventional procedures, the technical considerations involved, and the potential use of other interventional procedures, such as radiofrequency ablation, in combination with splenic arterial interventions. Familiarity with the complications that can result from these interventional procedures, including abscess formation and pancreatitis, also is important.

Yttrium-90 microsphere therapy for hepatic malignancy: devices, indications, technical considerations, and potential complications.

Management of hepatic malignancies is a ubiquitous medical problem. Surgical resection of primary or metastatic liver cancer, with or without adjuvant chemotherapy, is the most effective method for enhancing survival; however, hepatic malignancies in the vast majority of patients are unresectable both at initial manifestation and at recurrence. In these patients, palliative cytoreductive therapies may help to retard tumor progression and therefore favorably alter the course of the disease. Since hepatic neoplasms are principally supplied by the hepatic artery, various arterially delivered cytotoxic agents have been developed to achieve these objectives. Recently, the Food and Drug Administration approved the transarterial administration of yttrium-90 microspheres for liver-directed therapy. Effective use of these devices requires knowledge of the accumulated clinical experience and a dedicated multidisciplinary effort to ensure optimal outcomes and avoid therapy-specific life-threatening complications.

Pilot study of Flt3 ligand comparing intraperitoneal with subcutaneous routes on hematologic and immunologic responses in patients with peritoneal carcinomatosis and mesotheliomas.

PURPOSE: This study compared the clinical toxicity and hematological effects of i.p. and s.c. administration of fms-like tyrosine kinase-3-ligand (Flt3-L; Amgen, Thousand Oaks, CA), a truncated glycoprotein that increases dendritic cells (DCs) and monocytes. EXPERIMENTAL DESIGN: Patients with peritoneal carcinomatosis or mesothelioma were randomly assigned to treatment with Flt3-L (25 micro g/kg, maximum 1500 micro g), i.p. or s.c., days 1-5 and 8-12, then changed to the alternative route at 4 weeks. Treatment was continued s.c. or i.p. at 8 weeks. RESULTS: Fifteen patients (14 evaluable) were randomized to receive i.p. (n = 8) or s.c. (n = 7) injections. Their median age was 55 years (range, 40-68 years). Primary tumors were as follows: ovarian/peritoneal cancer (n = 9); gastrointestinal cancer (n = 2); and mesothelioma (n = 4). Treatment was well tolerated without serious toxicity (24 i.p. cycles; 32 s.c. cycles). Treatment (i.p. or s.c.) resulted in significant increases in WBCs (WBC, monocytes, and Lin(-)DR(+) DCs), and platelets (during washout). Both interleukin (IL)-12(p70) and IL-10 were secreted by monocyte-derived DCs after in vitro exposure to maturation factors. Increased IL-12 versus IL-10 secretion responses and higher proportions of the CD11c(+) DC subset in post-Flt3-L specimens suggested a maturational shift toward the monocyte-derived DC phenotype had occurred. Three patients (2 with mesothelioma and 1 with gastrointestinal cancer) had stable disease for 8, 8, and 12+ months, respectively. CONCLUSIONS: Flt3-L, administered either i.p. or s.c., is well tolerated and produced similar increases in monocytes, DCs, and platelets. DCs from peripheral blood and peritoneal fluids showed cell surface phenotypic and cytokine maturational responses to activation stimuli. These findings suggested that Flt3-L, in combination with suitable activating agents, could be developed further in patients with epithelial ovarian cancer.