Dynamic ctDNA Mutational Complexity in Patients with Melanoma Receiving Immunotherapy

BACKGROUND

Circulating tumour DNA (ctDNA) analysis promises to improve the clinical care of people with cancer, address health inequities and guide translational research. This observational cohort study used ctDNA to follow 29 patients with advanced-stage cutaneous melanoma through multiple cycles of immunotherapy.

METHOD

A melanoma-specific ctDNA next-generation sequencing (NGS) panel, droplet digital polymerase chain reaction (ddPCR) and mass spectrometry analysis were used to identify ctDNA mutations in longitudinal blood plasma samples from Aotearoa New Zealand (NZ) patients receiving immunotherapy for melanoma. These technologies were used in conjunction to identify the breadth and complexity of tumour genomic information that ctDNA analysis can reliably report.

RESULTS

During the course of immunotherapy treatment, a high level of dynamic mutational complexity was identified in blood plasma, including multiple BRAF mutations in the same patient, clinically relevant BRAF mutations emerging through therapy and co-occurring sub-clonal BRAF and NRAS mutations. The technical validity of this ctDNA analysis was supported by high sample analysis-reanalysis concordance, as well as concordance between different ctDNA measurement technologies. In addition, we observed > 90% concordance in the detection of ctDNA when using cell-stabilising collection tubes followed by 7-day delayed processing, compared with standard EDTA blood collection protocols with rapid processing. We also found that the undetectability of ctDNA at a proportion of treatment cycles was associated with durable clinical benefit (DCB).

CONCLUSION

We found that multiple ctDNA processing and analysis methods consistently identified complex longitudinal patterns of clinically relevant mutations, adding support for expanded clinical trials of this technology in a variety of oncology settings.

Effect of Microdoses of Incisional Antibiotics on the Rate of Surgical Site Infections in Skin Cancer Surgery: A Randomized Clinical Trial

Importance

Surgical site infections (SSIs) represent a costly and preventable complication of cutaneous surgery. However, there is a paucity of randomized clinical trials investigating antibiotic prophylaxis for reducing SSIs in skin cancer surgery, and evidence-based guidelines are lacking. Incisional antibiotics have been shown to reduce the rate of SSIs before Mohs micrographic surgery, but this represents a small subset of skin cancer surgery.

Objective

To determine whether microdosed incisional antibiotics reduce the rate of SSIs before skin cancer surgery.

Design, Setting, and Participants

In this double-blind, controlled, parallel-design randomized clinical trial, adult patients presenting to a high-volume skin cancer treatment center in Auckland, New Zealand, for any form of skin cancer surgery over 6 months from February to July 2019 were included. Patient presentations were randomized to one of 3 treatment arms. Data were analyzed from October 2021 to February 2022.

Interventions

Patients received an incision site injection of buffered local anesthetic alone (control), buffered local anesthetic with microdosed flucloxacillin (500 µg/mL), or buffered local anesthetic with microdosed clindamycin (500 µg/mL).

Main Outcomes and Measures

The primary end point was the rate of postoperative SSI (calculated as number of lesions with SSI per total number of lesions in the group), defined as a standardized postoperative wound infection score of 5 or more.

Results

A total of 681 patients (721 total presentations; 1133 total lesions) returned for postoperative assessments and were analyzed. Of these, 413 (60.6%) were male, and the mean (SD) age was 70.4 (14.8) years. Based on treatment received, the proportion of lesions exhibiting a postoperative wound infection score of 5 or greater was 5.7% (22 of 388) in the control arm, 5.3% (17 of 323) in the flucloxacillin arm, and 2.1% (9 of 422) in the clindamycin arm (P = .01 for clindamycin vs control). Findings were similar after adjusting for baseline differences among arms. Compared with lesions in the control arm (31 of 388 [8.0%]), significantly fewer lesions in the clindamycin arm (9 of 422 [2.1%]; P < .001) and flucloxacillin (13 of 323 [4.0%]; P = .03) arms required postoperative systemic antibiotics.

Conclusions and Relevance

This study evaluated the use of incisional antibiotics for SSI prophylaxis in general skin cancer surgery and compared the efficacy of flucloxacillin vs clindamycin relative to control in cutaneous surgery. The significant reduction in SSI with locally applied microdosed incisional clindamycin provides robust evidence to inform treatment guidelines in this area, which are currently lacking.

Trial Registration

anzctr.org.au Identifier: ACTRN12616000364471.

Seven-colour multiplex immunochemistry/immunofluorescence and whole slide imaging of frozen sections

Multiplex Immunochemistry/Immunofluorescence (mIHC/IF) aims to visualise multiple biomarkers in a single tissue section and is especially powerful when used on slide scanners coupled with digital analysis tools. mIHC/IF is commonly employed in immuno-oncology to characterise features of the tumour microenvironment (TME) and correlate them with clinical parameters to guide prognostication and therapy. However, mIHC/IF can be applied to a wide range of organisms in any physiological or disease context. Recent innovation has extended the number of markers that can be detected using slide scanners well beyond the 3-4 markers typically reported in traditional fluorescence microscopy. However, these methods often require sequential antibody staining and stripping, and are not compatible with frozen tissue sections. Using fluorophore-conjugated antibodies, we have established a simple mIHC/IF imaging workflow that enables simultaneous staining and detection of seven markers in a single section of frozen tissue. Coupled with automated whole slide imaging and digital quantification, our data efficiently revealed the tumour-immune complexity in metastatic melanoma. Computational image analysis quantified the immune and stromal cell populations present in the TME as well as their spatial interactions. This imaging workflow can also be performed with an indirect labelling panel consisting of primary and secondary antibodies. Our new methods, combined with digital quantification, will provide a valuable tool for high-quality mIHC/IF assays in immuno-oncology research and other translational studies, especially in circumstances where frozen sections are required for detection of particular markers, or for applications where frozen sections may be preferred, such as spatial transcriptomics.

Readability, reliability and credibility of online patient information on skin grafts

BACKGROUND

Skin grafting reflects a common dermatological procedure for closing skin defects. Patient education is important for managing expectation and optimising skin graft take. While health information is increasingly accessed on the internet, there are no existing studies assessing their quality.

METHODS

The first 25 results from Google, Microsoft Bing and Yahoo! search engines using the term 'skin graft' were analysed using a variety of standard instruments. Readability was assessed using the Flesch-Kincaid Grade score (FKG), Gunning Fog Index (GFI), Simple Measure of Gobbledygook (SMOG) and the New Dale-Chall Readability Index (NDC). Reliability was assessed using the DISCERN instrument and credibility with the Journal of the American Medical Association Benchmark Criteria (JAMA). Transparency was identified by presence of the Health On the Net Foundation Code certification (HON-code).

RESULTS

Seventy-five websites were identified. After exclusion, forty-three remaining websites were analysed with average FKG, GFI and SMOG scores of 7.8, 10.1 and 10.7, respectively. The average NDC was 5.9. The average reliability was fair with a DISCERN score based on the first 15 questions of the instrument of 42.6. The mean JAMA score was 2, and 9 websites displayed the HON-code certificate.

CONCLUSIONS

Readability, reliability and credibility of online health information regarding skin grafting can be improved. Health care providers should critically assess existing online patient information or develop alternative material to educate patients undergoing skin graft surgery.

Microbiology of surgical site infections (SSIs) following skin cancer surgery

BACKGROUNDS

Surgical site infections (SSIs) represent one of the most common and potentially preventable sources of morbidity and healthcare cost escalation associated with skin cancer surgery. There is a lack of data reporting organisms cultured from SSIs in skin surgery, with guidelines for antibiotic prophylaxis based on common skin pathogens rather than actual cultured organisms. In this study, we sought to define the cultured microbiology of SSIs specific to skin cancer surgery and test these against empiric treatment guidelines.

METHODS

All consenting patients presenting to the Auckland regional skin cancer treatment centre over a 6-month period were included. Patients receiving any form of antibiotics within a week prior to surgery were excluded. All wounds were assessed postoperatively, with clinically significant infections identified as those with a standardized wound infection score of 4 (range 0-7) and/or prescribed post-operative antibiotics within 3 weeks of surgery. Wound cultures were recorded.

RESULTS

About 104 clinically significant SSIs were identified from 333 lesions treated, with cultures available in 27%. Cultured organisms included MSSA (79%), MRSA (14%), coagulase-negative Staphylococci (11%), and 'skin flora' (14%). Empiric guidelines inaccurately predicted effective treatment in 14% of cases, exclusively due to MRSA.

CONCLUSION

To our knowledge this is the first comprehensive report of SSI microbiology following skin cancer surgery. The overwhelmingly predominant organisms were Staphylococcus sp. (76%), with the rate of MRSA approaching prevalence warranting empiric first-line treatment. These data help inform effective rationalized empiric antibiotic treatment, when indicated, for optimal outcome following skin surgery.

A survey of surgical management of the sentinel node positive melanoma patient in the post-MSLT2 era

BACKGROUND

The evidence-based management of melanoma patients with a positive sentinel lymph node biopsy (SLNB) has undergone a dramatic shift following publication of practice-changing surgical trials demonstrating no melanoma-specific survival advantage for completion lymph node dissection (CLND) in this scenario. We aimed to survey how surgeons' clinical practice had shifted in response to new evidence from these trials, and at a time when there was starting to become available systemic adjuvant treatments for AJCC Stage III melanoma patients.

METHODS

A web-based survey consisting of practice-based questions and hypothetical clinical scenarios about current melanoma practice with regard to positive sentinel node biopsy was developed and sent to the surgical members of a Melanoma and Skin Cancer (MASC) Trials group in December 2018. Responses were analysed using descriptive statistics.

RESULTS

There were 212 invitations sent and 65 respondents (31%). Respondents were from 17 countries, 94% of whom practice in specialist melanoma centres or at referral centres. Of these 97% were familiar with the MSLT2 and DeCOG-SLT clinical trials. At survey, 5% of respondents reported routinely recommending CLND and 55% recommend CLND in selected cases. Respondents were most likely to recommend CLND when multiple SLNs were positive. Important factors for surgical decision-making mentioned included size of SLN deposit, number of positive SLNs and likely compliance with the recommended surveillance regimen.

CONCLUSION

In line with rapid adoption of published evidence, surgical management of Stage III melanoma has altered significantly, with few surgeons within the cohort now performing routine CLNDs after positive SLNB.

Impact of Shave Biopsy on Diagnosis and Management of Cutaneous Melanoma: A Systematic Review and Meta-Analysis

BACKGROUND

Melanoma is the most lethal skin cancer. Excision biopsy is generally recommended for clinically suspicious pigmented lesions; however, a proportion of cutaneous melanomas are diagnosed by shave biopsy. A systematic review was undertaken to investigate the impact of shave biopsy on tumor staging, treatment recommendations, and prognosis.

METHODOLOGY

The MEDLINE, Embase, and Cochrane Library databases were searched for relevant articles. Data on deep margin status on shave biopsy, tumor upstaging, and additional treatments on wide local excision (WLE), disease recurrence, and survival effect were analyzed across studies.

RESULTS

Fourteen articles from 2010 to 2020 were included. In total, 3713 patients had melanoma diagnosed on shave biopsy. Meta-analysis revealed a positive deep margin in 42.9% of shave biopsies. Following WLE, change in tumor stage was reported in 7.7% of patients. Additional treatment was recommended for 2.3% of patients in the form of either further WLE and/or sentinel lymph node biopsy. There was high heterogeneity across studies in all outcomes. Four studies reported survival, while no studies found any significant difference in disease-free or overall survival between shave biopsy and other biopsy modalities.

CONCLUSIONS

Just over 40% of melanomas diagnosed on shave biopsy report a positive deep margin; however, this translated into a change in tumor stage or treatment recommendations in relatively few patients (7.7% and 2.3%, respectively), with no impact on local recurrence or survival among the studies analyzed.

Is Surgical Site Infection (SSI) after skin surgery affected by home municipal versus non-municipal water supply?

PURPOSE

SSI represent one of the most common sources of morbidity and escalated healthcare costs in skin cancer management. It has been shown that exposing wounds to treated water does not increase SSIs, however a large proportion of Australasian patients reside in rural areas dependant on roof or bore collected water for their primary water supply, and no data exist regarding the association between tank water supply and SSI following skin surgery.

METHODOLOGY

A nine-month retrospective analysis of patients undergoing skin cancer surgery at the Auckland Regional Plastic Surgery Unit was performed. Wounds assessed using a validated wound infection scoring system. Rates of SSI analysed against various clinical factors (water supply, smoking status, immunocompromise, glucose intolerance) and surgical factors (type of reconstruction, ulceration, lesion site, surface area of lesion).

RESULTS

857 lesions were excised from 357 patients over the period studied. 718 lesions (83.7%) had municipal and 139 lesions (16.3%) had non-municipal water as their primary supply. Overall rate of clinically significant SSI was 15.6%, with no difference between municipal and non-municipal water groups (15.6% vs. 15.8% P = 0.946). Further subgroup analysis did not reveal any difference in rate of SSI based on type of surgical closure (direct closure, skin graft vs. flap).

CONCLUSION

Non-municipal water supply was not associated with change in SSI relative to home municipal water supply in patients receiving skin cancer surgery. Our data supplements existing literature that water exposure does not influence SSI following skin surgery irrespective of primary home water supply.

Both Bone Forearm Infected Nonunion: Report of a One-Bone Free Fibula Flap Salvage and Literature Review

Background: Both bone forearm infective nonunions represent a rare but functionally limb threatening condition. Method: We report a successful salvage of a severe near total both bone diaphysial osteomyelitis by conversion to a one-bone forearm with free fibula flap. A literature review on forearm salvage addressing both bone defects was performed. Results: Bony union was achieved at 4 months with a highly functional extremity salvage in our case. Conclusion: While very little prior experience has been reported for long segmental both bone forearm infected nonunions, we report of this highly satisfactory salvage using one-bone free tissue transfer strategy. We also provided our literature review with history, indication and evolution of individualized treatment options for this difficult surgical condition.

Distinctive Subpopulations of Stromal Cells Are Present in Human Lymph Nodes Infiltrated with Melanoma

Metastasis of human tumors to lymph nodes (LN) is a universally negative prognostic factor. LN stromal cells (SC) play a crucial role in enabling T-cell responses, and because tumor metastases modulate their structure and function, this interaction may suppress immune responses to tumor antigens. The SC subpopulations that respond to infiltration of malignant cells into human LNs have not been defined. Here, we identify distinctive subpopulations of CD90⁺ SCs present in melanoma-infiltrated LNs and compare them with their counterparts in normal LNs. The first population (CD90⁺ podoplanin⁺ CD105⁺ CD146⁺ CD271⁺ VCAM-1⁺ ICAM-1⁺ α-SMA⁺) corresponds to fibroblastic reticular cells that express various T-cell modulating cytokines, chemokines, and adhesion molecules. The second (CD90⁺ CD34⁺ CD105⁺ CD271⁺) represents a novel population of CD34⁺ SCs embedded in collagenous structures, such as the capsule and trabeculae, that predominantly produce extracellular matrix. We also demonstrated that these two SC subpopulations are distinct from two subsets of human LN pericytes, CD90⁺ CD146⁺ CD36⁺ NG2^- pericytes in the walls of high endothelial venules and other small vessels, and CD90⁺ CD146⁺ NG2⁺ CD36^- pericytes in the walls of larger vessels. Distinguishing between these CD90⁺ SC subpopulations in human LNs allows for further study of their respective impact on T-cell responses to tumor antigens and clinical outcomes.

Evaluation of a novel database for quality assurance at a head and neck service in New Zealand: an audit of free flap head and neck reconstruction

BACKGROUND

Clinical audit is a critical quality improvement exercise, yet efficient audit tools are lacking. The main objective of this study was to evaluate a recently deployed database in facilitating the process of clinical audit, and the secondary objective was to evaluate the outcomes of free flap reconstruction of the head and neck at our centre.

METHODS

A head and neck cancer-specific database was customized to suit the needs of our head and neck multidisciplinary team. Data has been entered prospectively into this database since March of 2018. An audit of free flap reconstruction of the head and neck over a 12-month period was performed using the database and analysed as a case study to examine its efficacy as a clinical audit tool. Additionally, the outcomes of free flap reconstruction at our centre were compared to those reported in the international literature.

RESULTS

The database allows flexible and specific queries, analysis and export of data, and can provide immediate results. However, issues with data quality and completeness were identified. In this audit, the overall 30-day complication rate and 30-day mortality in patients undergoing free flap reconstruction of the head and neck were 58% and 3%, respectively.

CONCLUSION

The database is fit for its intended purpose as an audit tool. Outcomes of free flap reconstruction of the head and neck at our centre are comparable to those of institutions overseas.

Evolving Threat of Community Acquired Methicillin Resistant Staphylococcus aureus Upper Extremity Infections in the South Pacific: 2011-2015

Background: Community Acquired Methicillin Resistant Staphylococcus aureus (CA-MRSA) rates have been increasing worldwide and contribute to a growing "global health security threat" as reported by the WHO. Our group previously reported an overall rate of 7% in CA-MRSA upper extremity infections between 2004-2009 at the Auckland Regional Hand Unit. This fell below the Center for Disease Control (CDC) recommendation for empiric antimicrobial cover once local rates exceed 10-15%. We examined prevalence and characteristics of CA-MRSA upper extremity infections in our region over a subsequent 5-year period. Methods: One thousand two hundred and fifty-two patients with upper extremity infections requiring operative management between 2011 and 2015 inclusive were included in this study. Associated clinical characteristics were recorded including ethnicity, cultured organisms, antibiotic sensitivities, infection rate, and treatment practice. Results: One hundred and fifty (12%) of patients had culture positive CA-MRSA upper extremity infections. There was an increasing annual trend. Of note, rates of CA-MRSA in the Maori and Pacific Island ethnic subpopulations exceeded 15% in 2014 and 2015. Susceptibilities, associated factors and patient demographics are reported. Conclusions: Our unit enjoys significantly lower rates of CA-MRSA upper extremity infections than has been reported internationally. However, trends are increasing relative to our prior 6-year report, and the threshold for empiric treatment has been met within the Maori and Pacific Island ethnic subpopulations. This evolving threat is also highlighted by increasing cases of multi-drug resistant CA-MRSA. Evolving regional guidelines for empiric coverage of CA-MRSA among high-risk ethnic subpopulations identified by this study are underway.

Epidemiology and survival of Merkel cell carcinoma in New Zealand: A population-based study between 2000 and 2015 with international comparison

BACKGROUND/OBJECTIVES

Merkel cell carcinoma is an aggressive neuroendocrine skin cancer. Australian studies report high incidence and poor survival rates compared internationally. While New Zealand has a comparable UV index and racial composition to Australia, survival outcomes are currently unknown. The role of Merkel cell polyoma virus in oncogenesis of Merkel cell carcinoma is an active area of research. We describe the incidence and survival of Merkel cell carcinoma in New Zealand with correlation to demographic and clinical factors including regional polyoma virus prevalence.

METHODS

Retrospective study of population-based data from the New Zealand Cancer Registry. Incidence rates were directly standardised to the US standard 2000 population. Survival was investigated using Kaplan-Meier and multivariable Cox regression models.

RESULTS

Six hundred and one cases were diagnosed in New Zealand between 2000 and 2015. The overall incidence rate was 0.96/100 000 population. Merkel cell carcinoma is more common in males, elderly and on sun-exposed areas. Eighteen percent of patients were diagnosed with distant metastasis at time of presentation. The overall 5-year survival rate and relative 5-year survival rate were 31% and 45%, respectively. Mortality was 1.9 and 2.5 times higher for stage III and IV disease, respectively, relative to stage I/II disease. Patients over age 80 had twice the mortality compared to those aged 60-69.

CONCLUSIONS

New Zealand has a high incidence of Merkel cell carcinoma and poor survival outcomes when compared internationally. We have the highest proportion of distant metastatic disease at time of diagnosis. Further research into the role of nonpolyoma-related Merkel cell carcinoma is warranted to improve Merkel cell carcinoma outcomes in New Zealand and abroad.

Essential Components of Melanoma Histopathological Reporting: The Surgical Oncologist's Perspective

Histopathological reporting plays a critical role in guiding the surgical oncologist's management plan in treatment of primary cutaneous melanoma. The International Collaboration on Cancer Reporting (ICCR) espouses various components of structured histopathological reporting as "essential" or "recommended." From a surgical oncologist's perspective, we discuss the clinical relevance of each essential component, as well as prognostic and treatment implications with regard to treatment planning.

Sunscreen compliance with regional clinical practice guidelines and product labeling standards in New Zealand

INTRODUCTION For general practitioners, practice nurses and community pharmacists in New Zealand, a core duty is to educate patients about sun protection. We aimed to evaluate compliance of locally available sunscreens with regional clinical practice guidelines and sunscreen labelling standards, to assist clinicians in advising consumers on sunscreen selection. METHODS We audited all sunscreens available at two Auckland stores for three New Zealand sunscreen retailers. We then assessed compliance with accepted regional clinical practice guidelines for sun protection from the New Zealand Guidelines Group. We further assessed compliance with regional Australia/New Zealand consumer standards for sunscreen labelling. RESULTS All sunscreens satisfied clinical guidelines for broad-spectrum protection, and 99% of sunscreens met or exceeded clinical guidelines for minimal Sun Protection Factor. Compliance with regional standardized labelling guidelines is voluntary in New Zealand and 27% of audited sunscreens were not fully compliant with SPF labelling standards. DISCUSSION Sunscreens were generally compliant with clinical guidelines for minimal sun protection. However there was substantial noncompliance with regional recommendations for standardized sunscreen labelling. Primary health care clinicians should be aware that this labelling noncompliance may mislead patients into thinking some sunscreens offer more sun protection than they do. Mandatory compliance with the latest regional labelling standards would simplify sunscreen selection by New Zealand consumers. KEYWORDS Sunscreen; Sun Protection Factor; SPF; Skin Neoplasms; Melanoma; Skin Cancer Prevention.

COMMUNITY ACQUIRED METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS HAND INFECTIONS: A SOUTH PACIFIC PERSPECTIVE — CHARACTERISTICS AND IMPLICATIONS FOR ANTIBIOTIC COVERAGE

Purpose: Community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) infections are reported to be increasing worldwide. In the United States when rates exceed 15% empiric treatment is suggested. The aim of our study was to determine local rates and treatment of CA-MRSA within our region.

Methods: Nine hundred and forty-two patients were admitted to our service during a six-year period with culture-positive hand infections identified from operative cultures at the time of surgery.

Results: Sixty-six (7.0%) patients had CA-MRSA positive cultures identified. Thirty-two (48.5%) patients were noted to have remained on antibiotic treatment that did not reflect their MRSA positive status after cultures returned. Despite this, re-admission and re-operation rates were low and comparable to our non-MRSA control group.

Conclusions: Within our CA-MRSA group, current rates do not support automatic empiric treatment for CA-MRSA. Based on sensitivity data, co-trimoxazole and intravenous vancomycin are appropriate and effective antibiotic treatment within our region. Our data supports the importance of drainage of pyogenic infections in helping to resolve complicated hand infections.

Treatment of infantile haemangioma with captopril

BACKGROUND

Infantile haemangioma (IH) has recently been reported as an aberrant proliferation and differentiation of a primitive mesoderm-derived haemogenic endothelium regulated by the renin-angiotensin system (RAS), leading us to propose angiotensin converting enzyme (ACE) as a potential therapeutic target.

OBJECTIVES

To present initial results of our open-labelled observational clinical trial using captopril, an ACE inhibitor (ACEi), in the treatment of problematic proliferating IH.

METHODS

After initial screening investigations, infants with problematic IH were admitted for initiation of captopril with a 0·1 mg kg(-1) test dose orally, followed by 0·15 8-hourly over 24 h. This was then followed by dose escalation to 0·3 mg kg(-1) 8-hourly for another 24 hours. The dosage was increased to 0·5 mg kg(-1) 8-hourly 1 week later, if a noticeable involution had not already occurred. The response of IH to captopril was documented clinically and photographically before and after treatment and any side-effect was recorded.

RESULTS

Two boys and six girls aged 5-22 weeks (mean 12·9) with problematic IH were recruited with the lesions located in nasal tip (n = 1), cervicofacial (n = 3), periorbital (n = 1) and perineal (n = 2) areas, and shoulder (n = 1). Transient mild renal impairment occurred in one subject but resolved spontaneously. No other complication was observed. The IHs in all patients responded to captopril at a dosage of 1·5 mg kg(-1) daily which led to a dramatic response in three, moderate response in two, and slow response in three patients. Continued involution of IHs was observed during the follow-up period of 8-19 months (mean 15·8) in all subjects. Treatment was ceased at 14 months of age in seven patients with no rebound growth. In the remaining patient, rapid healing occurred with ongoing gradual reduction in the size and colour of a large ulcerated retroauricular lesion following 5·5 months of treatment. The lesion was excised to address its persistent distortion of the ear.

CONCLUSIONS

The response of IH to an ACEi supports a critical role for the RAS in IH and represents a paradigm shift in the understanding and treatment of this enigmatic condition.

CASE REPORT Superior Gluteal Artery Perforator Flap Breast Reconstruction Salvage Following Late Venous Congestion After Discharge

OBJECTIVE

Microvascular thrombosis is a dreaded complication of free tissue transfer, especially in breast reconstruction. Failure often leads to complete loss of the reconstruction and affects the patient both physically and psychologically. Fortunately, most vascular compromises occur early (within 24-36 hours) while the patient is still in the hospital and intervention takes place prior to irreversible thrombosis of the microvasculature. However, failures beyond 96 hours generally have dismal prognosis, especially because the patient is already home.

METHODS

A case of successful salvage is reported after an uncomplicated superior gluteal artery perforator flap performed for breast reconstruction returned from home with thrombosis of the venous pedicle the morning of postoperative day 5.

RESULTS

The pedicle was promptly explored and the venous patency reestablished using a combination of mechanical and chemical thrombolysis. At her 2-year follow-up, there was no evidence of fat necrosis and a satisfactory aesthetic outcome was achieved.

CONCLUSION

Late salvage of failing free flap breast reconstruction from home is possible. Educating the patient on importance of self-examination is critical to salvage. The hospital system also needs to have the resources to handle such emergencies in order for rapid operative mobilization to expedite the patient's care.

Prefabrication and prelamination applications in current aesthetic facial reconstruction

Prefabrication and prelamination techniques can offer significant advantage in aesthetic facial reconstruction. Specifically, they can be applied to expand the recruitment and assembly of optimal tissues for better approximation of aesthetic ideals. Some of their unique abilities are presented, and their advantages, limitations, and technical pointers are provided. The place for prelamination and prefabrication in the burgeoning era of composite tissue transplantation is addressed. Some of the relevant features and interdependencies among these procedures as they relate to aesthetic facial reconstruction are discussed.

The effect of muscle flap transposition to the fracture site on TNFalpha levels during fracture healing

The trauma and sepsis that follow open fractures and wounds may lead to the production of various cytokines. Understanding wound healing requires a direct knowledge of the specific cytokines and the respective wound fluid levels that are present at the wound site. An animal model was designed that mimics the open fracture and the clinical repair of the human, high-energy open fracture. Canine right tibiae were fractured with a penetrating, captive-bolt device, then repaired in a standard clinical fashion using an interlocking intramedullary nail. Before primary wound closure, microdialysis probes were placed at the fracture site and in a muscle located at a contralateral site. Canines received one of the following experimental protocols: (1) tibial fracture (n = 5); (2) tibial fracture plus Staphylococcus aureus inoculation at the fracture site (n = 5); and (3) tibial fracture, S. aureus inoculation, and a rotational gastrocnemius muscle flap (n = 5). Microdialysis fluid samples were collected intermittently for 7 days. Tumor necrosis factor alpha (TNFalpha) levels at the fracture site were significantly elevated 3 to 34-fold (p<0.02), as compared with respective serum levels at all time points for all treatment groups. Fracture site TNFalpha levels were elevated (p<0.02) in days 1 through 6, as compared with the baseline and contralateral in all treatment groups. At days 1 through 6, the TNFalpha levels of the muscle flap group fracture site were significantly decreased by approximately 50 percent (p<0.05), as compared with the fractures without muscle flaps and regardless of additional S. aureus inoculation. On day 7, fracture site TNFalpha levels in all animal groups were similar, yet remained well above those of baseline TNFalpha. These results demonstrate that S. aureus does not further elevate TNFalpha levels in the presence of an open fracture and that a muscle flap reduces pro-inflammatory TNFalpha levels during early wound healing. This experimental model allows for the characterization of specific biological signals and cellular pathways that are influenced by bacterial infection and surgical closure. These data provide a scientific framework on which to judge or validate therapeutic regimens for open-fracture wound healing.