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Featured researches published by Robert D. Foster.


Annals of Surgery | 2000

Complex abdominal wall reconstruction: a comparison of flap and mesh closure.

Stephen J. Mathes; Paul M. Steinwald; Robert D. Foster; William Y. Hoffman; James P. Anthony

ObjectiveTo analyze a series of patients treated for recurrent or chronic abdominal wall hernias and determine a treatment protocol for defect reconstruction. Summary Background DataComplex or recurrent abdominal wall defects may be the result of a failed prior attempt at closure, trauma, infection, radiation necrosis, or tumor resection. The use of prosthetic mesh as a fascial substitute or reinforcement has been widely reported. In wounds with unstable soft tissue coverage, however, the use of prosthetic mesh poses an increased risk for extrusion or infection, and vascularized autogenous tissue may be required to achieve herniorrhaphy and stable coverage. MethodsPatients undergoing abdominal wall reconstruction for 106 recurrent or complex defects (104 patients) were retrospectively analyzed. For each patient, hernia etiology, size and location, average time present, technique of reconstruction, and postoperative results, including recurrence and complication rates, were reviewed. Patients were divided into two groups based on defect components: Type I defects with intact or stable skin coverage over hernia defect, and Type II defects with unstable or absent skin coverage over hernia defect. The defects were also assigned to one of the following zones based on primary defect location to assist in the selection and evaluation of their treatment: Zone 1A, upper midline; Zone IB, lower midline; Zone 2, upper quadrant; Zone 3, lower quadrant. ResultsA majority of the defects (68%) were incisional hernias. Of 50 Type I defects, 10 (20%) were repaired directly, 28 (56%) were repaired with mesh only, and 12 (24%) required flap reconstruction. For the 56 Type II defects reconstructed, flaps were used in the majority of patients (n = 48; 80%). The overall complication and recurrence rates for the series were 29% and 8%, respectively. ConclusionsFor Type I hernias with stable skin coverage, intraperitoneal placement of Prolene mesh is preferred, and has not been associated with visceral complications or failure of hernia repair. For Type II defects, the use of flaps is advisable, with tensor fascia lata representing the flap of choice, particularly in the lower abdomen. Rectus advancement procedures may be used for well-selected midline defects of either type. The concept of tissue expansion to increase both the fascial dimensions of the flap and zones safely reached by flap transposition is introduced. Overall failure is often is due to primary closure under tension, extraperitoneal placement of mesh, flap use for inappropriate zone, or technical error in flap use. With use of the proposed algorithm based on defect analysis and location, abdominal wall reconstruction has been achieved in 92% of patients with complex abdominal defects.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 1999

Vascularized bone flaps versus nonvascularized bone grafts for mandibular reconstruction: an outcome analysis of primary bony union and endosseous implant success.

Robert D. Foster; James P. Anthony; Arun Sharma; M. Anthony Pogrel

Functional restoration following resection or traumatic injury to the mandible depends on the reliability of the bony reconstruction to heal primarily and support endosseous implants. Although vascularized bone flaps (VBF) and nonvascularized bone grafts (NVBG) are both widely used to reconstruct the mandible, indications for each remain ill‐defined. The purpose of this study was to compare bone graft/flap healing and success of implant placement in patients reconstructed with VBF versus NVBG.


Annals of Surgery | 2009

Total Skin-sparing Mastectomy: Complications and Local Recurrence Rates in 2 Cohorts of Patients

Elisabeth R. Garwood; Dan H. Moore; Cheryl Ewing; E. Shelley Hwang; Michael Alvarado; Robert D. Foster; Laura Esserman

Purpose:Dissemination of the total skin-sparing mastectomy (TSSM) technique is limited by concerns of nipple viability, flap necrosis, local recurrence risk, and the technical challenge of this procedure. We sought to define the impact of surgical and reconstructive variables on complication rates and assess how changes in technique affect outcomes. Patients and Methods:We compared the outcomes of TSSM in 2 cohorts of patients. Cohort 1: the first 64 TSSM procedures performed at our institution, between 2001 and 2005. Cohort 2: 106 TSSM performed between 2005 and 2007. Outcomes of cohort 1 were analyzed in 2005. At that time, potential risk factors for complications were identified, and efforts to minimize these risks by altering operative and reconstructive technique were then applied to patients in cohort 2. The impact of these changes on outcomes was assessed. Logistic regression was used to determine the association between predictor variables and adverse outcomes (Stata 10). Results:The predominant incision type in cohort 2 involved less than a third of the nipple areola complex (NAC), and the most frequent reconstruction technique was tissue expander placement. Between cohort 1 and cohort 2, nipple survival rates rose from 80% to 95% (P = 0.003) and complication rates declined: necrotic complications (30% → 13%; P = 0.01), implant loss (31% → 10%; P = 0.005), skin flap necrosis (16%–11%; not significant), and significant infections (17%–9%, not significant). Incisions involving >30% of the NAC (P < 0.001) and reconstruction with autologous tissue (P < 0.001) were independent risk factors for necrotic complications. The local recurrence rate was 0.6% at a median follow-up of 13 months (range, 1–65), with no recurrences in the NAC. Conclusion:Focused improvement in technique has resulted in the development of TSSM as a successful intervention at our institution that is oncologically safe with high nipple viability and early low rates of recurrence. Identifying factors that contribute to complications and changing surgical and reconstructive techniques to eliminate risk factors has greatly improved outcomes.


Annals of Surgical Oncology | 2002

Skin-sparing mastectomy and immediate breast reconstruction: A prospective cohort study for the treatment of advanced stages of breast carcinoma

Robert D. Foster; Laura Esserman; James P. Anthony; Eun-sil S. Hwang; Hoang Do

BackgroundRecent published series demonstrate the safety and effectiveness of skin-sparing mastectomy (SSM) with immediate reconstruction for the treatment of early-stage breast carcinoma. Although several reports have retrospectively evaluated outcomes after breast reconstruction for locally advanced disease (stages IIB and III), no study has specifically considered immediate breast reconstruction after SSM for locally advanced disease.MethodsFrom 1996 to 1998, 67 consecutive patients with breast carcinoma underwent SSM with immediate reconstruction and were prospectively observed. From this group of patients, those with locally advanced disease (stage IIB, n=12; stage III, n=13) were analyzed separately. Tumor characteristics, adjuvant therapy, type of reconstruction, operative time, complications, hospital stay, and incidence of local recurrence and distant metastasis were noted.ResultsBreast reconstruction consisted of a transverse rectus abdominis myocutaneous flap (n=22) or a latissimus flap plus an implant (n=4). The median operative time was 5.5 hours; the average hospital stay was 5.2 days. Complications required reoperation in three patients (12%): partial skin flap necrosis in two and partial abdominal skin necrosis in one. Surgery on the opposite breast for symmetry was required in one patient (4%). Postoperative adjuvant therapy was not significantly delayed (median interval, 32 days). With a median length of follow-up of 49.2 months (range, 33–64 months), local recurrence was present in only one patient (4%), with successful local salvage treatment, and distant metastasis was present in four patients (16%).ConclusionsSSM with immediate reconstruction seems safe and effective and has a low morbidity for patients with advanced stages of breast carcinoma. Local recurrence rates and the incidence of distant metastasis are not increased compared with those of patients who have had modified radical mastectomies without reconstruction.


Plastic and Reconstructive Surgery | 2001

Giant congenital melanocytic nevi: the significance of neurocutaneous melanosis in neurologically asymptomatic children.

Robert D. Foster; Mary L. Williams; A. J. Barkovich; William Y. Hoffman; Stephen J. Mathes; Ilona J. Frieden

Patients with a giant congenital melanocytic nevus can develop melanotic tumors characterized by central nervous system involvement, termed leptomeningeal melanocytosis or neurocutaneous melanosis. Although symptomatic neurocutaneous melanosis is rare, we previously reported distinct magnetic resonance (MR) findings of T1 shortening, strongly suggestive of neurocutaneous melanosis, in 30 percent (6 of 20) of children with giant congenital melanocytic nevi who presented initially without neurological symptoms. The purpose of this study was to determine the incidence of neurocutaneous melanosis in high‐risk patients and its long‐term clinical significance. Magnetic resonance imaging was recommended for all 46 patients with “at‐risk” giant congenital melanocytic nevi involving the skin overlying the dorsal spine or scalp. The clinical histories and follow‐up of these patients were evaluated by retrospective chart review. Forty‐two underwent MR imaging of the brain and 11 underwent additional MR scanning of the spinal cord. Abnormalities were identified in 14 of 43 MR studies, and 23 percent (n = 10) had T1 shortening indicative of melanotic rests within the brain or meninges. None had associated masses or leptomeningeal thickening. The most common areas of involvement in these 10 included the amygdala (n = 8), cerebellum (n = 5), and pons (n = 3). In the group of 11 patients with spinal MR scans, a tethered spinal cord was demonstrated in one. Additional abnormalities were detected by MR scanning, including a middle cranial fossa arachnoid cyst, a Chiari type I malformation, and a crescentic enhancement that subsequently resolved. Clinical follow‐up averaging 5 years (range, 2 to 8 years) revealed that only one of the 46 patients evaluated developed neurological symptoms, manifested as developmental delay, hypotonia, and questionable seizures but no other signs of neurocutaneous melanosis. No patient has developed a cutaneous or central nervous system melanoma. Magnetic resonance findings of neurocutaneous melanosis are relatively common, even in asymptomatic children with giant congenital melanocytic nevi. Although these findings suggest an increased lifetime risk of central nervous system melanoma, they do not signify the eventual development of symptomatic neurocutaneous melanosis during childhood. (Plast. Reconstr. Surg. 107: 933, 2001.)


Archives of Surgery | 2008

Optimizing the total skin-sparing mastectomy.

Akushla Wijayanayagam; Anjali S. Kumar; Robert D. Foster; Laura Esserman

HYPOTHESIS Dissection of subnipple tissue to spare the entire skin envelope of the breast (total skin-sparing mastectomy) is a feasible option in appropriately selected patients and yields an excellent final cosmetic outcome. DESIGN Prospective surgical technique outcomes study. SETTING University-based breast care referral center. PATIENTS Total skin-sparing mastectomy with preservation of the nipple-areola complex was performed in 64 breasts in 43 women. Indications for total skin-sparing mastectomy included prophylaxis (n = 29), invasive carcinoma (n = 24), and ductal carcinoma in situ (n = 11). INTERVENTIONS Preoperative magnetic resonance imaging was used to select patients and to confirm absence of disease within 2 cm of the nipple. Nipple tissue was serially sectioned at pathologic analysis. Circumareolar/nipple-areola free graft, inframammary, crescentic mastopexy, areola crossing, and radial incisions were used. Immediate reconstruction was performed with implant or tissue expander placement or latissimus dorsi muscle, transverse rectus abdominis muscle, or deep inferior epigastric perforator muscle flaps. MAIN OUTCOME MEASURES Nipple-areola complex skin survival, implant loss, skin flap necrosis, wound infection, and occult neoplasm. RESULTS Nipple-areola complex skin survival was complete in 80% of patients (n = 51) and partial in 16% (n = 10); it was highest with the radial incision at 97% survival (n = 34). Occult ductal carcinoma in situ in the nipple-areola complex was found in 2 patients (3%), and the affected nipple-areola complex was subsequently removed. Other complications included implant loss, total skin-sparing skin flap necrosis, and infection. Although follow-up is limited, no patients have exhibited cancer recurrence. CONCLUSIONS Total skin-sparing mastectomy is a viable surgical option in selected patients with breast neoplasm and those who choose prophylactic mastectomy, and may increase the willingness of women to consider mastectomy to reduce their risk of breast cancer.


British Journal of Plastic Surgery | 1997

Ischial pressure sore coverage: a rationale for flap selection

Robert D. Foster; James P. Anthony; Stephen J. Mathes; William Y. Hoffman

The role of wound debridement and flap coverage in treating pressure sores is clearly established. However, criteria and supportive clinical data for specific flap selection and the sequence of flaps for coverage of the ischium remain ill-defined. From 1979-1995, 114 consecutive patients underwent flap coverage of 139 ischial pressure sores. Preoperative risk factors, prior flap history, defect size, flap success, complication rates, and the length of hospitalization were retrospectively evaluated and compared for 112 flaps in 87 patients. Flap success was defined as a completely healed wound. Average follow-up was 10 months (range: 1 month-9 years). Overall, 83% (93/112) of the flaps healed. In the majority of cases (75%, 84/112), wound debridement and flap reconstruction was achieved in a single stage. However, there were significant differences in the healing rates among the various flaps used. The inferior gluteus maximus island flap and the inferior gluteal thigh flap had the highest success rates, 94% (32/34) and 93% (25/27), respectively, while the V-Y hamstring flap and the tensor fascia lata flap had the poorest healing rates, 58% (7/12) and 50% (6/12), respectively. Flap success was not significantly affected by the age of the patient or the prior number of flaps used and preoperative risk factors were equally distributed across all types of flaps. The overall complication rate was 37% (41/112), most commonly from a slight wound edge dehiscence (n = 16) that healed with local wound care within one month postoperatively. Results of this study show that proper flap selection and the appropriate sequence of flap use significantly improve success rates for ischial pressure sore coverage in both the short- and long-term. Based upon flap reliability (successful healing rates), reusability, and the need to preserve as many future flap options as possible, a rationale for flap selection is presented which can be individualized to any patient.


American Journal of Surgery | 1998

Donor-specific tolerance induction in composite tissue allografts.

Robert D. Foster; Larry Fan; Michael Niepp; Christina Kaufman; Timothy H. McCalmont; Nancy L. Ascher; Suzanne T. Ildstad; James P. Anthony

BACKGROUND Although prolonged composite tissue allograft (CTA) survival is achievable in animals using immunosuppressive drugs, long-term immunosuppression of CTAs in the clinical setting would be unacceptable for most patients. The purpose of this study was to develop a model for reliable CTA tolerance induction in the adult rat across a strongly antigenic MHC mismatch without the need for long-term immunosuppression. METHODS Chimeras were prepared using rat strains with strong MHC incompatibility [WF (RT1Au) + ACI (RT1Aa) --> WF, n = 13]. Syngeneic (WF) and allogeneic (ACI) bone marrow (BM) was harvested and T-cell depleted. Following confirmation of T-cell depletion by flow cytometry, a mixture of T-cell depleted syngeneic and allogeneic BM was injected into the recipient animals (all recipients pretreated with low-dose irradiation, 500 to 700 cGy). In addition, the recipient animals received a single dose of ALS (10 mg) 5 days prior to bone marrow transplantation (BMT) and tacrolimus (1 mg/kg/day) from the day prior to BMT to 10 days postoperatively. Rat chimeras were characterized by flow cytometry at 3 and 12 months after BM reconstitution and following hindlimb transplantation. RESULTS Peripheral blood lymphocyte chimerism (WF/ACI) remained stable >12 months after BM reconstitution in 10 of 13 animals. Multilineage chimerism of both lymphoid and myeloid lineages was present, suggesting that engraftment of the pluripotent rat stem cell had occurred. In animals with donor chimerism >60%, there was no sign of limb rejection for the duration of the study. All animals with chimerism <20% developed moderate signs of rejection clinically and histologically. Gross motor and sensory reinnervation (weight bearing, toe spread) occurred at >60 days in 6 of 9 rats. Postoperative flow cytometry studies demonstrated stable chimerism in all animals studied (n = 7). CONCLUSIONS Stable mixed allogeneic chimerism can be achieved in a rat hindlimb model of composite tissue allotransplantation. Hindlimb allografts to mixed allogeneic chimeras exhibit prolonged, rejection-free survival. This represents the first reliable model demonstrating rejection-free CTA survival in an adult animal without the long-term use of immunosuppressive agents across a strongly antigenic MHC mismatch.


Plastic and Reconstructive Surgery | 2011

The effects of acellular dermal matrix in expander-implant breast reconstruction after total skin-sparing mastectomy: results of a prospective practice improvement study.

Anne Warren Peled; Robert D. Foster; Elisabeth R. Garwood; Dan H. Moore; Cheryl Ewing; Michael Alvarado; Hwang Es; Laura Esserman

Background: Neither outcome after total skin-sparing mastectomy and expander-implant reconstruction using acellular dermal matrix nor a strategy for optimal acellular dermal matrix selection criteria has been well described. Methods: Prospective review of three patient cohorts undergoing total skin-sparing mastectomy with preservation of the nipple-areola complex and immediate expander-implant reconstruction from 2006 to 2010 was performed. Cohort 1 (no acellular dermal matrix) comprised 90 cases in which acellular dermal matrix was not used. Cohort 2 (consecutive acellular dermal matrix) included the next 100 consecutive cases, which all received acellular dermal matrix. Cohort 3 (selective acellular dermal matrix) consisted of the next 260 cases, in which acellular dermal matrix was selectively used based on mastectomy skin flap thickness. Complication rates were compared using chi-square analysis. Results: The study included 450 cases in 288 patients. Mean follow-up was 25.5 months. Infection occurred in 27.8 percent of the no–acellular dermal matrix cases, 20 percent of the consecutive cases, and 15.8 percent of the selective cases (p = 0.04). Unplanned return to the operating room was required in 23.3, 11, and 10 percent of cases, respectively (p = 0.004). Expander-implant loss occurred in 17.8, 7, and 5 percent of cases, respectively (p = 0.001). Additional analysis of the odds ratios of developing complications after postmastectomy radiation therapy demonstrated a specific protective benefit of acellular dermal matrix in irradiated patients. Conclusions: Acellular dermal matrix use in expander-implant reconstruction after total skin-sparing mastectomy reduced major postoperative complications in this study. Maximal benefit is achieved with selected use in patients with thin mastectomy skin flaps and those receiving radiation therapy. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.


Transplantation | 2001

Mixed allogeneic chimerism as a reliable model for composite tissue allograft tolerance induction across major and minor histocompatibility barriers.

Robert D. Foster; Nancy L. Ascher; Timothy H. McCalmont; Michael Neipp; James P. Anthony; Stephen J. Mathes

Background. Although prolonged composite tissue allograft (CTA) survival is achievable in animals using immunosuppressive drugs, long-term immunosuppression of CTAs in the clinical setting may be unacceptable for most patients. The purpose of this study was to develop a model for reliable CTA tolerance induction in the adult rat across a major MHC mismatch without the need for long-term immunosuppression. Methods. Mixed allogeneic chimeras were prepared by using rat strains with strong MHC incompatibility [WF (RT1Au), ACI (RT1Aa)] WF + ACI→WF, n=23. The bone marrow (BM) of recipient animals was pretreated with low-dose irradiation (500–700 cGy), followed by reconstitution with a mixture of T cell-depleted syngeneic (WF) and allogeneic (ACI) cells. Additionally, the recipient animals received a single dose of anti-lymphocyte serum (10 mg) 5 days before bone marrow transplantation (BMT) and tacrolimus (1 mg/kg/day) from the day before BMT to 10 days post-BMT. Hindlimb transplants were performed 12 months after BMT. Five animals received a limb allograft irradiated (1000 cGy) just before transplantation. Rat chimeras were characterized (percentage of donor cells present within the bloodstream) by flow cytometry at 3 and 12 months after BM reconstitution and after hindlimb transplantation. Results. Peripheral blood lymphocyte chimerism (WF/ACI) remained stable >12 months after BM reconstitution in 18/23 animals. Multi-lineage chimerism of both lymphoid and myeloid lineages was present, suggesting that engraftment of the pluripotent rat stem cell had occurred. In animals with donor chimerism >60% (n=18) no sign of limb rejection was present for the duration of the study. All animals with chimerism <20% (n=5) developed moderate signs of rejection clinically and histologically. Gross motor and sensory reinnervation (weight bearing, toe spread) developed at >60 days in 14/21 rats. Postoperative flow cytometry studies demonstrated stable chimerism in all animals studied (n=10). Five out of five animals with irradiated limb transplants showed no sign of GVHD at >100 days. Conclusions. Stable mixed allogeneic chimerism can be achieved in a rat hindlimb model of composite tissue allotransplantation. Hindlimb allografts to mixed allogeneic chimeras exhibit prolonged, rejection-free survival. Partial functional return should be expected. The BM transplanted as part of the hindlimb allograft plays a role in the etiology of GVHD. Manipulating that BM before transplantation may influence the incidence of GVHD. This represents the first reliable rat hindlimb model demonstrating rejection-free CTA survival in an adult animal across a major MHC mismatch without the long-term need for immunosuppressive agents.

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Laura Esserman

University of California

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Hani Sbitany

University of California

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Cheryl Ewing

University of California

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Frederick Wang

University of California

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Barbara Fowble

University of California

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Merisa Piper

University of California

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