Patient-level costs in margin re-excision for breast-conserving surgery

BACKGROUND

High rates of reoperation following breast-conserving surgery (BCS) for positive margins are associated with costs to healthcare providers. The aim was to assess the quality of evidence on reported re-excision costs and compare the direct patient-level costs between patients undergoing successful BCS versus reoperations after BCS.

METHODS

The study used data from women who had BCS with or without reoperation at a single institution between April 2015 and March 2016. A systematic review of health economic analysis in BCS was conducted and scored using the Quality of Health Economic Studies (QHES) instrument. Financial data were retrieved using the Patient-Level Information and Costing Systems (PLICS) for patients. Exchange rates used were: US $1 = £0·75, £1 = €1·14 and US $1 = €0·85.

RESULTS

The median QHES score was 47 (i.q.r. 32·5-79). Only two of nine studies scored in the upper QHES quartile (score at least 75). Costs of initial lumpectomy and reoperation were in the range US $1234-11786 and $655-9136 respectively. Over a 12-month interval, 153 patients had definitive BCS and 59 patients underwent reoperation. The median cost of reoperations after BCS (59 patients) was £4511 (range 1752-18 019), representing an additional £2136 per patient compared with BCS without reoperation (P < 0·001).

CONCLUSION

The systematic review demonstrated variation in methodological approach to cost estimates and a paucity of high-quality cost estimate studies for reoperations. Extrapolating local PLICS data to a national level suggests that getting BCS right first time could result in substantial savings.

Best-practice care pathway for improving management of mastitis and breast abscess

BACKGROUND

Surgical subspecialization has resulted in mastitis and breast abscesses being managed with unnecessary admission to hospital, prolonged inpatient stay, variable antibiotic prescribing, incision and drainage rather than percutaneous aspiration, and loss to specialist follow-up. The objective was to evaluate a best-practice algorithm with the aim of improving management of mastitis and breast abscesses across a multisite NHS Trust. The focus was on uniformity of antibiotic prescribing, ultrasound assessment, admission rates, length of hospital stay, intervention by aspiration or incision and drainage, and specialist follow-up.

METHODS

Management was initially evaluated in a retrospective cohort (phase I) and subsequently compared with that in two prospective cohorts after introduction of a breast abscess and mastitis pathway. One prospective cohort was analysed immediately after introduction of the pathway (phase II), and the second was used to assess the sustainability of the quality improvements (phase III). The overall impact of the pathway was assessed by comparing data from phase I with combined data from phases II and III; results from phases II and III were compared to judge sustainability.

RESULTS

Fifty-three patients were included in phase I, 61 in phase II and 80 in phase III. The management pathway and referral pro forma improved compliance with antibiotic guidelines from 34 per cent to 58·2 per cent overall (phases II and III) after implementation (P = 0·003). The improvement was maintained between phases II and III (54 and 61 per cent respectively; P = 0·684). Ultrasound assessment increased from 38 to 77·3 per cent overall (P < 0·001), in a sustained manner (75 and 79 per cent in phases II and III respectively; P = 0·894). Reductions in rates of incision and drainage (from 8 to 0·7 per cent overall; P = 0·007) were maintained (0 per cent in phase II versus 1 per cent in phase III; P = 0·381). Specialist follow-up improved consistently from 43 to 95·7 per cent overall (P < 0·001), 92 per cent in phase II and 99 per cent in phase III (P = 0·120). Rates of hospital admission and median length of stay were not significantly reduced after implementation of the pathway.

CONCLUSION

A standardized approach to mastitis and breast abscess reduced undesirable practice variation, with sustained improvements in process and patient outcomes.

Abstract P2-04-01: Withdrawn

This abstract was withdrawn by the authors.

Adequacy of diagnostic tests and surgical management of symptomatic invasive lobular carcinoma of the breast

INTRODUCTION

Invasive lobular carcinoma (ILC) presents diagnostic and therapeutic challenges as it produces subtle radiological changes. It has been suggested that it is not suitable for breast conserving surgery (BCS). The aim of this study was to ascertain the diagnostic adequacy of modern mammography and ultrasonography in the context of a fast track symptomatic diagnostic clinic in the UK. It also sought to compare the mastectomy, re-excision and BCS rates for ILC with those for invasive ductal carcinoma (IDC).

METHODS

A retrospective analysis of prospectively collected data was carried out on all new symptomatic cancers presenting to the one-stop diagnostic clinic of a single breast unit between 1998 and 2007.

RESULTS

Compared with IDC, ILC was significantly larger at presentation (46mm vs 25mm), needed re-excision after BCS more often (38.8% vs 22.3%) and required mastectomy more frequently (58.8% vs 40.8%). Although mammography performs poorly in diagnosing ILC compared with IDC, when combined with ultrasonography, sensitivity of the combined imaging was not significantly different between these two histological types.

CONCLUSIONS

Provided ultrasonography is performed, standard radiological imaging is adequate for initial diagnosis of symptomatically presenting ILC but some additional preoperative workup should clearly be employed to reduce the higher number of reoperations for this histological type.

Validation of an oncoplastic breast simulator for assessment of technical skills in wide local excision

Background

Simulation enables safe practice and facilitates objective assessment of technical skills. However, simulation training in breast surgery is rare and assessment remains subjective. The primary aim was to evaluate the construct validity of technical skills assessments in wide local excision (WLE).

Methods

Surgeons of different grades performed a WLE of a 25-mm palpable tumour on an in-house synthetic breast simulator. Procedures were videotaped (blinded), reviewed retrospectively, and independently rated against a procedure-specific global rating scale by two consultant breast surgeons. Specimen radiographs were obtained and the macroscopic distance from the ‘tumour’ edge to the resection margin was recorded in four cardinal directions. Expert consensus was used to construct an Oncoplastic Deviation Score (ODS), assigning points for excessively wide (more than 10 mm) and, conversely, close (less than 5 mm) macroscopic margins.

Results

Thirty-four surgeons (12 consultant surgeons, 12 specialty trainees and 10 core trainees) participated in the study. Video-based rating scores varied hierarchically with operator expertise (P &lt; 0·050). Inter-rater reliability was excellent (α ≥ 0·80, P &lt; 0·050 for all scales), and inter-rater agreement was moderate (κ = 0·132–0·361, P &lt; 0·050 for all scales). Statistically significant differences were observed on pairwise comparisons between each grade of surgeon in scores for ‘exposure’, ‘skin flap development’, ‘glandular remodelling’, ‘skin closure’ and ‘final product review’ (P &lt; 0·050). Consultants received significantly fewer ODS points than specialty trainees (P = 0·012) and core trainees (P = 0·028). Compared with experts (median 9·0 mm), wider margins were observed amongst specialty trainees (median 12·0 mm) and narrower margins amongst core trainees (median 7·1 mm) (P = 0·001).

Conclusion

Video ratings of performance and a proposed ODS differentiate surgeons based on technical skills in WLE and may be useful for objective assessment of breast surgery trainees.

Sentinel lymph node biopsy after neo-adjuvant chemotherapy in patients with breast cancer: Are the current false negative rates acceptable?

The advent of sentinel lymph node biopsy has revolutionised surgical management of axillary nodal disease in patients with breast cancer. Patients undergoing neo-adjuvant chemotherapy for large breast primary tumours may experience complete pathological response on a previously positive sentinel node whilst not eliminating the tumour from the other lymph nodes. Results from 2 large prospective cohort studies investigating sentinel lymph node biopsy after neo-adjuvant chemotherapy demonstrate a combined false negative rate of 12.6-14.2% and identification rate of 80-89% with the minimal acceptable false negative rate and identification rate being set at 10% and 90%, respectively. A false negative rate of 14% would have been classified as unacceptable when compared to the figures obtained by the pioneers of sentinel lymph node biopsy which was 5% or less.

An open-label study of lapatinib in women with HER-2-negative early breast cancer: the lapatinib pre-surgical study (LPS study)

BACKGROUND

This phase II, open-label, multicentre study aimed to evaluate changes in cell proliferation and biomarkers, as well as efficacy of lapatinib in treatment-naïve patients with HER-2-negative primary breast cancer.

PATIENTS AND METHODS

Patients received 1500 mg lapatinib for 28-42 days before surgery with repeat biopsies and measurements. The primary end point was inhibition of cell proliferation measured by Ki67; the secondary end points included clinical response, adverse events and changes in FOXO3a, FOXM1, p-AKT and HER-3.

RESULTS

Overall, there was no significant reduction in Ki67 with treatment (assessment carried out in 28 of 31 subjects enrolled). However, four patients (14%) showed a reduction in Ki67 ≥50%. Four of 25 patients (16%) had a partial response to treatment judged by sequential ultrasound measurements. Response, in terms of either Ki67 or ultrasound, did not relate to changes in any biomarker assessed at baseline, including the estrogen receptor (ER) and epidermal growth factor receptor (EGFR). However, all four clinical responders were HER-3 positive, as were three of four Ki67 responders.

CONCLUSIONS

Overall, a pre-surgical course of lapatinib monotherapy had little effect on this group of patients; however, in subsets of patients, especially those with HER-3-positive tumors, we observed either reduction in proliferation (Ki67) or tumor size; EGFR/ER status had no impact.

P5-21-04: Patient Attitudes towards Undergoing Additional Breast Biopsy for Research Purposes

Background

Acquisition of additional breast tissue for research has become integral to breast oncology research but no data exists regarding patient attitudes to additional, non-diagnostic biopsies. Baseline research biopsies may be obtained as part of the diagnostic process as extra passage(s) of the needle through a ‘generic consent’ process, or as an additional biopsy event after carcinoma diagnosis has been confirmed and eligibility for a specific study has been established. This study sought to explore patient perspectives to such biopsies.

Patients and Methods

Patients attending breast clinics were recruited to complete a questionnaire prior to their consultation (and any interaction with researchers or clinicians seeking consent for research biopsies) which examined willingness to undergo an extra fine needle aspirate (FNA) and/or core needle biopsy (CNB) for research either at time of the diagnostic biopsy (B1) or after diagnosis (B2). Descriptions of FNA and CNB procedures were supplied to those with no prior experience. Patient perspectives towards donating surplus tissue left over from a diagnostic procedure and/or surgery for storage for future research was also explored.

Results: 100 patients were recruited, 42% with a prior history of breast carcinoma, 23% with family history of breast carcinoma and 65%/ 42% with previous experience of CNB/FNA respectively for either benign or malignant disease. Willingness to undergo additional biopsy was greater for the B1 than the B2 time point, but equivalent for CNB and FNA (willingness CNB B1 50% vs B2 26%, willingness FNA B1 50% vs B2 29%). A statistically significant increase in willingness to undergo CNB and FNA at B1 and/or B2 was seen in association with prior diagnosis of breast cancer, family history of breast cancer, previous visit to breast clinic and prior experience of breast biopsy. Reasons for willingness or unwillingness were recorded. 83% of patients expressed a willingness to allow surplus tissue to be stored in a biobank for future research.

Conclusions: When asked by questionnaire prior to clinic consultation, additional research biopsy was much more acceptable if undertaken at time of initial diagnostic biopsy rather than at a later time point. Acceptability was equivalent for CNB and FNA. Previous experience of biopsy, previous attendance to breast clinic, a prior history of breast cancer or family history of breast cancer increased acceptability suggesting that willingness is increased with knowledge of the biopsy procedure.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-21-04.

Sentinel node biopsy can replace four-node-sampling in staging early breast cancer

AIM

Four-node axillary sampling for breast cancer is an established method of staging the axilla in the United Kingdom. We report the sensitivity of sentinel node (SN) biopsy and compare it with that of four-node sampling.

METHODS

SN identification was attempted in 234 consecutive patients with unifocal breast cancers up to 25 mm in diameter on pre-operative ultrasound. A combination of isotope-labelled nanocolloid and patent blue dye techniques were used and SN were identified in 221 (94.5%). All patients underwent back-up four-node sampling and those with positive sentinel nodes on frozen section (FS) underwent immediate full axillary clearance.

RESULTS

Among those patients who had SN successfully identified, an average of 1.38 SN were identified per patient. Histological examination of the SN alone would have identified all node-positive patients that the four-node sample identified.

CONCLUSION

In patients who have SN identified, four-node axillary sampling does not provide any additional information.

Core biopsy versus FNAC for palpable breast cancers. Is image guidance necessary?

The aim of this study was to assess the efficacy of free-hand percutaneous core biopsy (FHCB) and to determine the role of fine needle aspiration cytology (FNAC) as diagnostic tools for palpable radiologically-suspicious breast lumps. This retrospective study was based on reviewing the clinical records of all patients diagnosed as having breast cancer between January 1999 and December 2000 and patients who had benign lesions, but suspicious breast imaging at triple assessment. Absolute sensitivity of FHCB for diagnosing cancer in palpable lesions was 98.7% compared with 51.3% for FNAC. The difference in the sensitivity of FHCB and FNAC was statistically significant (P<0.005, Wilcoxon matched pair test). Since 94.8% of radiologically-suspicious lumps were shown to be cancers, we advocate FHCB for all patients presenting with radiologically suspicious palpable lumps to our breast clinic. We also conclude that the sensitivity of FHCB for the diagnosis of malignancy in palpable radiologically-suspicious breast lesions is so high that image-guidance is unnecessary.

Sentinel node biopsy for breast cancer may have little to offer four-node-samplers

The aims of the study were to determine how often four node axillary sampling (4NAS) encompasses the sentinel node (SN) and to compare the relative sensitivity of 4NAS with sentinel node biopsy (SNB) for axillary node staging. 200 patients with breast cancer were preoperatively injected with 27 MBq 99m-Tc-labelled colloid adjacent to the tumour. At operation, standard 4NAS was performed. Each node was counted ex vivo using a probe. A search was then made to find a node with higher counts in vivo directed by the probe. If found, it was excised. Each node was submitted separately to pathology. A SN was identified in 191 patients (96%). The SN was contained in the 4NAS in 153 patients (80%) and identified separately in 38 patients (20%). Of 60 node-positive patients, 49 were positive by 4NAS and SNB, the SN was not identified in 2 and in 8 the SN was falsely negative compared with 4NAS. For 1 patient, the SN was positive and the 4NAS negative. SNB performed using radiolabelled colloid has no advantage over 4NAS when nodes are assessed by standard histological technique.

Continuous antibiotic treatment for experimental abdominal sepsis: effects on organ inflammatory cytokine expression and neutrophil sequestration

BACKGROUND

Tumour necrosis factor (TNF) alpha and interleukin (IL) 1 beta are produced in the lung after peritonitis and may contribute to neutrophil-mediated organ injury. It was hypothesized that, during experimental peritonitis, continuous rather than intermittent antibiotic therapy would reduce lung expression of TNF-alpha and IL-1 beta messenger RNA (mRNA) and neutrophil sequestration.

METHODS

After caecal ligation and puncture, mice received either intermittent or continuous cefoxitin, or continuous metronidazole or aztreonam. Cytokine mRNAs were determined by reverse transcription differential polymerase chain reaction and lung neutrophil content by myeloperoxidase (MPO) assay.

RESULTS

Continuous cefoxitin reduced median (interquartile range (i.q.r.)) lung IL-1 beta mRNA expression ((ratio to beta-actin): continuous 0.18 (0.14-0.34), intermittent 0.46 (0.44-0.49), saline 0.43 (0.38-0.53), P < 0.05) and median (i.q.r.) lung MPO content (continuous 22.5 (9.7-40), intermittent 65 (57.5-76), saline 47 (41-64), P < 0.05) compared with intermittent therapy and saline controls. Continuous infusion was also associated with reduced bacteraemia (P < 0.05) but not serum TNF-alpha or endotoxin levels. Both continuous metronidazole and aztreonam reduced lung MPO concentration (P < 0.05) and TNF-alpha and IL-1 beta mRNA expression (P < 0.05) compared with those in saline controls. These effects were dependent on a reduction in the number of susceptible bacteria rather than serum TNF-alpha or endotoxin levels.

CONCLUSION

The stimulus for organ inflammatory cytokine production and neutrophil sequestration during peritonitis is the level of bacteraemia present, which is more effectively controlled with continuous antibiotic therapy.

The role of cytokines, adhesion molecules, and chemokines in interleukin-2-induced lymphocytic infiltration in C57BL/6 mice

IL-2 mediates the regression of certain malignancies, but clinical use is limited because of associated toxicities, including parenchymal lymphocytic infiltration with multiple organ failure. Secondarily induced cytokines are important mediators of IL-2 toxicity and IL-2-induced lymphocyte-endothelial adherence and trafficking. The recently discovered C-C chemokines, RANTES (regulated on activation, normal T expressed and secreted) and macrophage inflammatory protein-1alpha, have also been implicated in lymphocytic migration. We hypothesized that IL-2 alters cytokine, C-C chemokine, and adhesion molecule expression in association with parenchymal lymphocytic infiltration. C57BL/6 mice were injected with 3x10(5) IU of IL-2 or 0.1 ml of 5% dextrose intraperitoneally every 8 h for 6 d, then killed. IL-2 induced massive lymphocytic infiltration in the liver and lung and moderate infiltration in the kidney in association with organ edema and dysfunction. Immunostaining showed increased intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression in association with this organ-specific lymphocytic infiltration. Flow cytometry showed increased expression of the corresponding ligands (lymphocyte function-associated antigen-1 and very late antigen-4) on splenocytes. IL-2 increased TNF-alpha mRNA and protein expression in the liver. Organs infiltrated by lymphocytes had increased TNF-alpha mRNA, whereas RANTES mRNA was increased in all organs, regardless of lymphocytic infiltration. IL-2 toxicity involves organ-specific TNF-alpha and RANTES production with increased ICAM-1 and VCAM-1 expression as potential mechanisms facilitating lymphocytic infiltration and organ dysfunction.

Passive immunization against tumor necrosis factor and interleukin-1 fails to reduce lung neutrophil sequestration in chronic sepsis

The proinflammatory cytokines tumor necrosis factor (TNF) and interleukin-1 (IL-1) are produced within the lung during sepsis, and may induce neutrophil sequestration resulting in neutrophil-mediated lung injury. We hypothesized that, if there is a cause and effect between TNF alpha or IL-1 production and lung neutrophil sequestration during chronic sepsis, TNF alpha mRNA and IL-1 mRNA levels in the lung after cecal ligation and puncture should correlate with the number of sequestered neutrophils as measured by the myeloperoxidase (MPO) content of the lung. To test this hypothesis, Swiss Webster mice were subjected to varying degrees of infectious challenge by single and double-puncture cecal ligation and puncture, or simultaneous antibiotic treatment, and their lungs and blood were harvested at 24 h. Lung TNF alpha and IL-1 beta mRNAs were measured by the reverse-transcription differential polymerase chain reaction, and MPO was measured by colorimetric assay. TNF alpha serum levels showed no correlation with the MPO content of the lung, whereas IL-1 levels were undetectable. Lung TNF alpha mRNA correlated weakly, and IL-1 beta mRNA exhibited a strong correlation with lung MPO (r = .9, p < .01), but administration of anti-TNF alpha- or anti-IL-1-neutralizing antibodies did not prevent a rise in lung MPO. IL-1 beta mRNA in bronchoalveolar macrophages correlated well with whole lung tissue IL-1 beta mRNA levels (r = .91, p < .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Intraoperative assessment of nodal status in the selection of patients with breast cancer for axillary clearance

Axillary node status was assessed by intraoperative contact cytology of four sampled nodes in each of 114 consecutive patients with operable breast cancer treated by wide local excision or mastectomy. At a mean follow-up of 18.7 months, 43 node-positive patients who underwent immediate axillary clearance had two locoregional and six distant recurrences with two deaths; four had arm oedema and one shoulder stiffness. There were no recurrences or arm and shoulder morbidity in 71 node-negative women who had no clearance or radiotherapy. The mean hospital stay was 4.3 days for patients having wide local excision versus 7.2 days for those undergoing excision and axillary clearance (P < 0.001), and 8.9 days for patients receiving a mastectomy versus 9.1 days for those having mastectomy and clearance (P not significant). Selective axillary clearance based on intraoperative contact cytology of four sampled nodes reduces hospital stay in patients treated by wide local excision and may lead to a reduction in arm morbidity without impairing disease control.

Endotoxin and tumour necrosis factor do not cause mortality from caecal ligation and puncture

Macrophage tumour necrosis factor-alpha (TNF-alpha) production is thought to represent an important pathogenic mechanism by which Gram-negative sepsis is mediated. We compared the effects of caecal ligation and puncture (CLP) on endotoxin-sensitive (C3H/HeSnJ) and endotoxin-resistant (C3H/HeJ) mice. Mortality after CLP for C3H/HeSnJ mice compared with C3H/HeJ mice was not significantly different (32% and 55%, respectively). When survivors were injected with lipopolysaccharide intraperitoneally on the 7th day after CLP, the mortality rate was 82% for C3H/HeSnJ mice versus 0% for C3H/HeJ mice (P < 0.0001). Serum endotoxin levels at 24 h after CLP were only slightly elevated. Serum TNF levels and peritoneal macrophage TNF production were undetectable in C3H/HeJ mice and were only slightly elevated in C3H/HeSnJ mice by 24 h after CLP. Peritoneal macrophage mRNA levels for TNF-alpha, IL-1 beta, and I-A alpha displayed a similar pattern in the two strains of mice, with a 2- to 3-fold increase in TNF-alpha and IL-1 beta mRNA levels by 24 h and a sharp decrease in I-A alpha mRNA by 24 h. The cause of mortality in mice that undergo CLP cannot be attributed to overwhelming endotoxemia and/or TNF production.

Enhanced survival from cecal ligation and puncture with pentoxifylline is associated with altered neutrophil trafficking and reduced interleukin-1 beta expression but not inhibition of tumor necrosis factor synthesis

BACKGROUND

Our preliminary results showed that pentoxifylline improves survival after cecal ligation and puncture (CLP), even though in this model inhibition of tumor necrosis factor (TNF) activity decreases survival. In this study we tested the hypothesis that pentoxifylline improves survival after CLP, not by inhibiting TNF synthesis but by exerting its effect on leukocyte adhesiveness, neutrophil sequestration, recruitment of cells into the focus of sepsis, and interleukin-1 (IL-1) expression.

METHODS

Pentoxifylline, 10 or 100 mg/kg/day, was administered to mice after CLP by infusion for 3 days. The following was measured at 24 hours for the group with improved survival: (1) serum TNF by enzyme-linked immunosorbent assay, (2) TNF and IL-1 beta mRNAs in lung and peritoneal macrophages by the differential polymerase chain reaction, (3) lung myeloperoxidase by a colorimetric assay, (4) leukocyte CD11b/CD18 by flow cytometry, and (5) peritoneal exudate cells by manual counting.

RESULTS

Only the low-dose pentoxifylline increased survival. Pentoxifylline reduced IL-1 beta mRNA expression in lung and peritoneal macrophages but not TNF mRNA or immunoreactive TNF in the serum. The myeloperoxidase content of lung was reduced by pentoxifylline, but leukocyte CD11b/CD18 expression did not change. Pentoxifylline increased the number of cells in the peritoneum after CLP.

CONCLUSIONS

Pentoxifylline improves survival after CLP without inhibiting TNF synthesis or expression of CD11b/CD18 on leukocytes. Pentoxifylline treatment reduced lung neutrophil sequestration and IL-1 beta mRNA levels and increased cell recruitment in the peritoneum.

Tissue tumor necrosis factor mRNA expression following cecal ligation and puncture or intraperitoneal injection of endotoxin

Tumor necrosis factor (TNF) has been implicated as a key mediator of the septic response. Although very high serum levels of TNF are detected in animal models of endotoxemia or gram-negative bacteremia, human patients with sepsis rarely have greatly elevated TNF serum levels. It has therefore been postulated that TNF may act in a paracrine fashion to cause local injury. In order to examine the role of locally produced TNF in sepsis, we compared serum TNF levels and TNF messenger RNA (mRNA) expression in various tissues following cecal ligation and puncture (CLP) or intraperitoneal injection of a sublethal dose of endotoxin. TNF mRNA expression was determined by the reverse transcription differential polymerase chain reaction using beta-actin as an internal standard. Serum levels of TNF were threefold higher after endotoxin administration compared to CLP. TNF mRNA in peritoneal macrophages rose fourfold after both endotoxin injection and CLP, with rapid return to normal in endotoxin-treated animals. There was a significant increase in TNF mRNA in the liver and lung, but not the spleen, during the first 24 hr after CLP. An increase in TNF mRNA was seen in all three tissues after injection of endotoxin. These results support the concept of locally produced TNF as a contributing factor in tissue damage and multiple organ failure during sepsis.

A rare cause of upper gastrointestinal bleeding

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Construction of transferrin-coated liposomes for in vivo transport of exogenous DNA to bone marrow erythroblasts in rabbits

A method for coating liposomes with transferrin is described. Such liposomes have been used for carrying exogenous DNA to rabbit bone marrow (BM) precursor cells, in vivo. A large amount of the DNA contained in the liposomes was delivered specifically into the erythroblasts of the test animals.