Non-invasive peripheral focused ultrasound neuromodulation of the celiac plexus ameliorates symptoms in a rat model of inflammatory bowel disease.

NEW FINDINGS: What is the central question of this study? Does peripheral non-invasive focused ultrasound targeted to the celiac plexus improve inflammatory bowel disease? What is the main finding and its importance? Peripheral non-invasive focused ultrasound targeted to the celiac plexus in a rat model of ulcerative colitis improved stool consistency and reduced stool bloodiness, which coincided with a longer and healthier colon than in animals without focused ultrasound treatment. The findings suggest that this novel neuromodulatory technology could serve as a plausible therapeutic approach for improving symptoms of inflammatory bowel disease. ABSTRACT: Individuals suffering from inflammatory bowel disease (IBD) experience significantly diminished quality of life. Here, we aim to stimulate the celiac plexus with non-invasive peripheral focused ultrasound (FUS) to modulate the enteric cholinergic anti-inflammatory pathway. This approach may have clinical utility as an efficacious IBD treatment given the non-invasive and targeted nature of this therapy. We employed the dextran sodium sulfate (DSS) model of colitis, administering lower (5%) and higher (7%) doses to rats in drinking water. FUS on the celiac plexus administered twice a day for 12 consecutive days to rats with severe IBD improved stool consistency scores from 2.2 ± 1 to 1.0 ± 0.0 with peak efficacy on day 5 and maximum reduction in gross bleeding scores from 1.8 ± 0.8 to 0.8 ± 0.8 on day 6. Similar improvements were seen in animals in the low dose DSS group, who received FUS only once daily for 12 days. Moreover, animals in the high dose DSS group receiving FUS twice daily maintained colon length (17.7 ± 2.5 cm), while rats drinking DSS without FUS exhibited marked damage and shortening of the colon (13.8 ± 0.6 cm) as expected. Inflammatory cytokines such as interleukin (IL)-1ß, IL-6, IL-17, tumour necrosis factor-α and interferon-γ were reduced with DSS but coincided with control levels after FUS, which is plausibly due to a loss of colon crypts in the former and healthier crypts in the latter. Lastly, overall, these results suggest non-invasive FUS of peripheral ganglion can deliver precision therapy to improve IBD symptomology.

Dermal melanoma: A report on prognosis, outcomes, and the utility of sentinel lymph node biopsy.

INTRODUCTION: Historically dermal melanoma (DM) has been labeled as either stage IIIB (in-transit) or stage IV (M1a) disease. We sought to investigate the natural history of DM and the utility and prognostic significance of sentinel lymph node biopsy (SLNB). METHODS: Patients with DM undergoing SLNB at a single center from 1998 to 2009 were identified. RESULTS: Eighty-three patients met criteria, 10 (12%) patients had a positive SLNB. Of those, 5 (50%) recurred (all with distant disease). Twenty-one (29%) of the 73 SLNB negative patients recurred and of those, 15 (71%) developed distant metastases, whereas 6 (29%) developed local or regional recurrence, including two false-negative regional nodal recurrences. No in-transit recurrences were recorded. Five-year recurrence-free and disease-specific survival was significantly better for patients with a negative SLNB versus positive SLNB (56.8% vs. 22.2% P = 0.02, 81.1% vs. 61.0%, P = 0.05, respectively). CONCLUSION: SLNB has prognostic significance for RFS and DSS, and should be utilized in the management of DM based on a >10% yield and low false-negative rate. Our data demonstrate patients with DM do not recur in an in-transit fashion, which along with the survival outcomes suggest the behavior of DM is consistent with primary cutaneous melanoma of similar thickness rather than an isolated in-transit or distant dermal metastasis from a regressed cutaneous primary.

Both tumor depth and diameter are predictive of sentinel lymph node status and survival in Merkel cell carcinoma.

BACKGROUND: The purposes of this study were 1) to determine the impact of primary tumor-related factors on the prediction of the sentinel lymph node (SLN) status and 2) to identify clinical and pathologic factors associated with survival in Merkel cell carcinoma (MCC). METHODS: An institutional review board-approved, retrospective review of patients with MCC treated between 1988 and 2011 at a single center was performed. Patients were categorized into 5 groups: 1) negative SLN, 2) positive SLN, 3) clinically node-negative but SLN biopsy not performed, 4) regional nodal disease without a known primary tumor, and 5) primary MCC with synchronous clinically evident regional nodal disease. Factors predictive of the SLN status were analyzed with logistic regressions, and overall survival (OS) and disease-specific survival (DSS) were analyzed with Cox models and competing risk models assuming proportional hazards, respectively. RESULTS: Three hundred seventy-five patients were analyzed, and 70% were male; the median age was 75 years. The median tumor diameter was 1.5 cm (range, 0.2-12.5 cm), and the median tumor depth was 4.8 mm (range, 0.3-45.0 mm). One hundred ninety-one patients underwent SLN biopsy, and 59 (31%) were SLN-positive. Increasing primary tumor diameter and increasing tumor depth were associated with SLN positivity (P = .007 and P = .017, respectively). Age and sex were not associated with the SLN status. Immunosuppression, increasing tumor diameter, and increasing tumor depth were associated with worse OS (P = .007, P = .003, and P = .025, respectively). DSS differed significantly by group and was best for patients with a negative SLN and worst for those with primary MCC and synchronous clinically evident nodal disease (P = .018). CONCLUSION: For patients with MCC, increasing primary tumor diameter and increasing tumor depth are independently predictive of a positive SLN, worse OS, and worse DSS. Tumor depth should be routinely reported when primary MCC specimens are being evaluated histopathologically.

Final trial report of sentinel-node biopsy versus nodal observation in melanoma.

BACKGROUND: Sentinel-node biopsy, a minimally invasive procedure for regional melanoma staging, was evaluated in a phase 3 trial. METHODS: We evaluated outcomes in 2001 patients with primary cutaneous melanomas randomly assigned to undergo wide excision and nodal observation, with lymphadenectomy for nodal relapse (observation group), or wide excision and sentinel-node biopsy, with immediate lymphadenectomy for nodal metastases detected on biopsy (biopsy group). Results No significant treatment-related difference in the 10-year melanoma-specific survival rate was seen in the overall study population (20.8% with and 79.2% without nodal metastases). Mean (± SE) 10-year disease-free survival rates were significantly improved in the biopsy group, as compared with the observation group, among patients with intermediate-thickness melanomas, defined as 1.20 to 3.50 mm (71.3 ± 1.8% vs. 64.7 ± 2.3%; hazard ratio for recurrence or metastasis, 0.76; P=0.01), and those with thick melanomas, defined as >3.50 mm (50.7 ± 4.0% vs. 40.5 ± 4.7%; hazard ratio, 0.70; P=0.03). Among patients with intermediate-thickness melanomas, the 10-year melanoma-specific survival rate was 62.1 ± 4.8% among those with metastasis versus 85.1 ± 1.5% for those without metastasis (hazard ratio for death from melanoma, 3.09; P<0.001); among patients with thick melanomas, the respective rates were 48.0 ± 7.0% and 64.6 ± 4.9% (hazard ratio, 1.75; P=0.03). Biopsy-based management improved the 10-year rate of distant disease-free survival (hazard ratio for distant metastasis, 0.62; P=0.02) and the 10-year rate of melanoma-specific survival (hazard ratio for death from melanoma, 0.56; P=0.006) for patients with intermediate-thickness melanomas and nodal metastases. Accelerated-failure-time latent-subgroup analysis was performed to account for the fact that nodal status was initially known only in the biopsy group, and a significant treatment benefit persisted. CONCLUSIONS: Biopsy-based staging of intermediate-thickness or thick primary melanomas provides important prognostic information and identifies patients with nodal metastases who may benefit from immediate complete lymphadenectomy. Biopsy-based management prolongs disease-free survival for all patients and prolongs distant disease-free survival and melanoma-specific survival for patients with nodal metastases from intermediate-thickness melanomas. (Funded by the National Cancer Institute, National Institutes of Health, and the Australia and New Zealand Melanoma Trials Group; ClinicalTrials.gov number, NCT00275496.).

Single-institution outcome experience using AlloDerm® as temporary coverage or definitive reconstruction for cutaneous and soft tissue malignancy defects.

Definitive reconstruction after excision of cutaneous and soft tissue malignancies is sometimes limited as a result of lack of native tissue coverage options, patient comorbidities, or pending permanent margin analysis. Acellular dermis (AlloDerm®) reconstruction offers an excellent coverage alternative in these situations. We describe our experience using AlloDerm for coverage of skin and soft tissue defects. An Institutional Review Board approved review of patients undergoing skin/soft tissue coverage with AlloDerm from 2006 to 2012 was performed. Clinicopathologic variables, early postoperative findings, and subjective final cosmetic outcome were analyzed. Sixty-seven patients underwent AlloDerm reconstruction. Melanoma (67%) was the most frequent diagnosis. The median defect size was 42 cm(2) (range, 2 to 340 cm(2)), involving predominantly the lower extremity (45%) or head and neck (32%). AlloDerm was intended for use as a temporary dressing in 64 per cent (43 of 67) and permanent coverage in 24 (36%). Ten patients required reexcision for positive margins. Twenty-five (37%) underwent split-thickness skin graft or flap coverage after AlloDerm placement. Radiation was administered to 16 patients (24%) after AlloDerm reconstruction within a median of 53 days after surgery (range, 18 to 118 days). At first postoperative examination (median, 11 days after surgery), 85 per cent had evidence of healthy AlloDerm incorporation. Cellulitis was the most frequent complication (13%), all resolving with oral antibiotics. AlloDerm reconstruction after skin and soft tissue resection offers a suitable coverage alternative and may serve as a bridge to permanent reconstruction or as a permanent biologic dressing of complex surgical defects. In situations in which adjuvant radiation is needed, AlloDerm can be used without major complications.

Combined analysis of phase III trials evaluating [99mTc]tilmanocept and vital blue dye for identification of sentinel lymph nodes in clinically node-negative cutaneous melanoma.

BACKGROUND: [(99m)Tc]Tilmanocept is a CD206 receptor-targeted radiopharmaceutical designed for sentinel lymph node (SLN) identification. Two nearly identical nonrandomized phase III trials compared [(99m)Tc]tilmanocept to vital blue dye. METHODS: Patients received [(99m)Tc]tilmanocept and blue dye. SLNs identified intraoperatively as radioactive and/or blue were excised and histologically examined. The primary end point, concordance, was the proportion of blue nodes detected by [(99m)Tc]tilmanocept; 90 % concordance was the prespecified minimum concordance level. Reverse concordance, the proportion of radioactive nodes detected by blue dye, was also calculated. The prospective statistical plan combined the data from both trials. RESULTS: Fifteen centers contributed 154 melanoma patients who were injected with both agents and were intraoperatively evaluated. Intraoperatively, 232 of 235 blue nodes were detected by [(99m)Tc]tilmanocept, for 98.7 % concordance (p < 0.001). [(99m)Tc]Tilmanocept detected 364 nodes, for 63.7 % reverse concordance (232 of 364 nodes). [(99m)Tc]Tilmanocept detected at least one node in more patients (n = 150) than blue dye (n = 138, p = 0.002). In 135 of 138 patients with at least one blue node, all blue nodes were radioactive. Melanoma was identified in the SLNs of 22.1 % of patients; all 45 melanoma-positive SLNs were detected by [(99m)Tc]tilmanocept, whereas blue dye detected only 36 (80 %) of 45 (p = 0.004). No positive SLNs were detected exclusively by blue dye. Four of 34 node-positive patients were identified only by [(99m)Tc]tilmanocept, so 4 (2.6 %) of 154 patients were correctly staged only by [(99m)Tc]tilmanocept. No serious adverse events were attributed to [(99m)Tc]tilmanocept. CONCLUSIONS: [(99m)Tc]Tilmanocept met the prespecified concordance primary end point, identifying 98.7 % of blue nodes. It identified more SLNs in more patients, and identified more melanoma-containing nodes than blue dye.

A collision of diseases: chronic lymphocytic leukemia discovered during lymph node biopsy for melanoma.

BACKGROUND: In the United States in 2012, there were 16,060 new cases of chronic lymphocytic leukemia (CLL). Often CLL is clinically occult and first detected during pathologic evaluation of the sentinel lymph node biopsy (SLNB). We reviewed our experience of patients with the coexisting diagnosis of melanoma and CLL. METHODS: An institutional review board-approved review was performed on patients with CLL and melanoma treated from 1995 to 2009 at Moffitt Cancer Center and compared with the incidence of melanoma and CLL in our tumor registry patients with breast, prostate, lung, and colon cancer. RESULTS: Fifty-two patients (44 males; median age, 71 years [range, 46-88]) were identified with concurrent diagnoses of melanoma and CLL. Twenty-two patients (42 %) had CLL on SLNB for their melanoma. Thirty-two patients (62 %) were diagnosed with melanoma before CLL. Concomitant or prior cancer diagnoses included nonmelanoma skin cancers (N = 29), prostate (N = 6), colorectal (N = 2), and Merkel cell carcinoma (N = 2). Five of 20 patients (25 %) had metastatic melanoma found at the time of SLNB. Patients with melanoma had a tenfold increase of CLL diagnosis compared with colorectal cancer patients, an eightfold increase compared to prostate cancer patients, and a fourfold increase compared with breast cancer patients. CONCLUSIONS: We have confirmed an increased association of CLL and melanoma. This may be related to an underlying immunologic defect; however, there has been scant investigation into this phenomenon. Surgeons and pathologists should understand this occurrence and recognize that not all grossly enlarged or abnormal sentinel lymph nodes in melanoma patients represent melanoma.

The unique clinical characteristics of melanoma diagnosed in children.

BACKGROUND: Studies have demonstrated a higher rate of nodal metastases in melanoma of childhood, but there is controversy about the overall prognosis relative to adults. We describe a large single-institution experience with pediatric melanoma and assess prognostic characteristics. METHODS: Retrospective review identified 126 patients diagnosed with melanoma at <21 years of age and referred for treatment from 1986 to 2011. Atypical lesions were excluded. Clinicopathologic characteristics were correlated with sentinel lymph node (SLN) status and outcomes. RESULTS: SLN biopsy was positive in 18 of 62 cases (29 %). Increasing Breslow thickness correlated with a positive SLN (p < 0.05). After a median follow-up of 5 years, there were 27 recurrences and 20 deaths. Positive SLN patients had significantly worse recurrence-free survival (RFS, p < 0.05) and significantly worse melanoma-specific survival (MSS, p = 0.05) compared with negative SLN patients. The 5-year RFS and MSS for positive SLN patients were 59.5 and 77.8 %, compared with 93.7 and 96.8 % for negative SLN patients. Recurrences and melanoma-related deaths were often seen beyond 5 years. No deaths have occurred in patients <12 years, but 9.1 % of patients 12-17 years and 17.2 % of patients 18-20 years died from melanoma (p = 0.291). CONCLUSIONS: Children with melanoma have higher rates of SLN metastases (29 %) than adults with comparable melanomas. Despite the higher incidence of nodal metastases, survival is equal to or better than what is reported for adults. However, long-term follow-up is necessary in this population since recurrences and deaths are often seen beyond 5 years.

Sentinel node biopsy is indicated for thin melanomas ≥0.76 mm.

BACKGROUND: A consensus for which patients with thin melanomas (≤1 mm) should undergo sentinel lymph node biopsy (SLNB) is not established. We describe a large single institution experience with SLNB for thin melanomas to determine factors predictive of nodal metastases. METHODS: Retrospective review from 2005 to 2010 identified 271 patients with thin melanomas who underwent SLNB, along with 13 additional patients not treated with SLNB who developed a nodal recurrence as first site of recurrence. Clinicopathologic characteristics were correlated with nodal status and outcome. RESULTS: Median age was 55 years, and 53% of patients were male. Median Breslow thickness was 0.85 mm. Overall, a positive sentinel lymph node (SLN) was found in 22 (8.1%) of 271 cases; 8.4% of melanomas ≥0.76 mm were SLN positive with 5% of T1a melanomas ≥0.76 mm and 13% of T1b melanomas ≥0.76 mm having SLN metastases. Only two of 33 highly selected patients with melanomas <0.76 mm (both T1b) had a positive SLN. Logistic regression analysis demonstrated that mitotic rate ≥1/mm(2) significantly correlated with nodal disease (p < 0.05) and ulceration correlated with SLN metastases (p < 0.05). Median follow-up was 2.1 years. Overall survival did not differ between positive and negative SLN patients (p = 0.53) but was worse for patients presenting with a nodal recurrence (p < 0.01). CONCLUSIONS: SLN metastases were seen in 8.4% of thin melanomas ≥0.76 mm, including 5% of T1a melanomas ≥0.76 mm. We believe these rates are sufficient to justify consideration of SLNB in these patients, while the indications for SLNB in melanomas <0.76 mm remain to be defined.

Integration and application of vitrified collagen in multilayered microfluidic devices for corneal microtissue culture.

This paper describes the fabrication and application of microfluidic devices containing collagen vitrigel (CV) used as both a functional and sacrificial cell growth substrate for the development of corneal microtissue patches. Within the device, vacuum fixation of the CV in a dehydrated state enables quick integration with standard multilayer soft lithographic techniques, while on-chip rehydration results in a gel-like collagen substrate for microfluidic cell culture. Fluidic connectivity to both the apical and basal side of the CV permits bilayered culture of epithelium and supporting stromal cell layers. In addition, microfluidic introduction of a collagenase etching media enables sacrificial degradation of the supporting CV membrane for development of barrier tissue constructs containing minimal synthetic substrate. The utility of this platform was evaluated by miniaturizing the standard transepithelial permeability (TEP) assay in order to measure the integrity of an array of corneal tissue micropatches.

The number of lymph nodes involved with metastatic disease does not affect outcome in melanoma patients as long as all disease is confined to the sentinel lymph node.

BACKGROUND: In melanoma, a direct relationship exists between the number of nodes involved with metastatic disease and prognosis. This study was undertaken to determine whether an individual with metastatic disease confined to the sentinel lymph nodes (SLNs) would have a better prognosis than individuals with metastatic disease that has spread to the non-SLNs, regardless of the number of nodes involved. METHODS: The study group consists of 229 melanoma patients with a positive SLN who underwent regional nodal dissection. Cox proportional hazard regression models were used to assess association of the number of SLNs and non-SLNs involved with disease with overall survival (OS) and disease-free survival (DFS). RESULTS: DFS and OS were unchanged regardless of how many SLNs were positive, as long as all disease was confined to SLNs. Among 183 patients without involvement of non-SLNs, OS remained the same despite an increasing number of SLNs involved (P = .59). This was true after controlling for ulceration, Breslow depth, age, sex, and adjuvant treatment. Once disease was present beyond the SLN, DFS and OS were negatively affected. Among patients with involvement of non-SLNs, there was no statistically significant association between the number of positive SLNs and survival. The risk of mortality increased with the number of non-SLNs involved with metastatic disease (P < .001). CONCLUSIONS: The number of regional nodes involved with metastatic disease does not affect DFS and OS if disease is confined to the SLNs. Consideration should be given to specifying SLN versus non-SLN involvement in the American Joint Committee on Cancer staging manual.

Limiting the morbidity of inguinal lymphadenectomy for metastatic melanoma.

BACKGROUND: Surgery is currently the primary treatment modality for metastatic melanoma involving the inguinal lymph nodes. However, inguinal lymph node dissections are associated with substantial morbidity including infection, wound dehiscence, lymphedema, seroma, and deep venous thromboembolism (DVT). Improved understanding is needed regarding the factors predisposing patients to complications and the operative and perioperative maneuvers that can decrease morbidity. METHODS: We reviewed recently published literature regarding the morbidity associated with lymphadenectomy in the treatment of inguinal metastatic melanoma. Where available, emphasis was focused on appropriately designed studies aimed at reducing treatment-related morbidity. When appropriate, the review was supplemented by our personal experience. RESULTS: Strategies to limit treatment-related morbidity involve optimizing the preoperative assessment, operative technique, and postoperative care. Establishing the diagnosis of nodal metastasis early using minimally invasive techniques is critical to reduce subsequent perioperative complications. Morbidity is higher for inguinal compared to cervical or axillary lymphadenectomy, and many variations in extent of inguinal lymphadenectomy and operative technique have been reported. The lack of definitive trials has led to controversy regarding surgical technique such as indications for pelvic lymphadenectomy ("deep" node dissection), saphenous vein preservation, and sartorius transposition. In the postoperative period, the use of DVT and lymphedema prophylaxis should be considered to potentially improve patient outcomes. CONCLUSIONS: While the morbidity of inguinal lymphadenectomy can be substantial, several straightforward pre- and postoperative measures can be instituted to limit morbidity. Controversy persists regarding the indications for and benefit of pelvic lymphadenectomy, saphenous vein preservation, and sartorius muscle transposition. A multi-institutional trial is currently in progress to investigate the safety of avoiding lymphadenectomy in patients with microscopic metastases in the sentinel node.

DNA methylation analysis on a droplet-in-oil PCR array.

We performed on-chip DNA methylation analysis using methylation-specific PCR (MSP) within an arrayed micro droplet-in-oil platform that is designed for more practical application of microfluidic droplet technologies in clinical applications. Unique features of this ready-to-use device include arrayed primers that are pre-deposited into open micro-reaction chambers and use of the oil phase as a companion fluid for both sample actuation and compartmentalization. These technical advantages allow for infusion of minute amounts of sample for arrayed MSP analysis, without the added complexities inherent in microfluidic droplet-based studies. Ease of use of this micro device is exemplified by analysis of two tumor suppressor promoters, p15 and TMS1 using an on-chip methylation assay. These results were consistent with standard MSP protocols, yet the simplicity of the droplet-in-oil microfluidic PCR platform provides an easy and efficient tool for DNA methylation analysis in a large-scale arrayed manner.

Surgical management of melanoma-in-situ using a staged marginal and central excision technique.

Melanoma-in-situ (MIS) represents 45% of all melanomas. The margins of MIS are often poorly defined with extensive subclinical disease. Standard fusiform excision with 5-mm margins results in positive margins in up to a third of cases. To decrease the incidence of involved margins, we use a staged excision approach for MIS. First, patients undergo excision under local anesthesia of a 2- to 3-mm "contoured" rim of tissue optimally 5 mm beyond the visible extent of the lesion. Formalin-fixed paraffin-embedded en face sections from this excision are then evaluated, if necessary with the aid of immunohistochemical stains. Any positive margins are further excised. When all margins are negative, the central area is then excised and reconstructed. A total of 61 patients with MIS or lentigo maligna melanoma underwent staged contoured excisions from 2004 to 2007 at Moffitt Cancer Center. We analyzed data only from patients with MIS of the head and neck. Patients with known invasive melanoma or non-head and neck primary disease were excluded. Demographics, tumor characteristics, margin status, number of stages, and type of reconstruction and recurrences were evaluated. Forty-nine patients with MIS of the head and neck, 28 (57%) male and 21 (43%) female, 42 to 88-years-old (median 72; mean 70), underwent staged contoured margin excision before definitive central tumor excision and reconstruction. The final surgical defect size ranged from 2 to 130 cm(2) (median 16 cm(2)). Twelve patients (24%) required reexcision of at least one margin; the median number of reexcisions was 1 (range 1-2). There seemed to be a positive association between lesion size and margin status (as well as number of excisions needed to clear the margin). Unsuspected invasive melanoma was found in the central specimen in six patients (12%). Even small tumors could have unsuspected invasive melanoma: invasive cancer was seen in 4 (21%) of 19 tumors < or =2 cm in greatest dimension and 2 (7%) of 30 > 2 cm, respectively. Surgical defects were reconstructed with flaps in 18 (37%), full-thickness grafts in 20 (41%), and split-thickness grafts in 10 patients (20%). Median time from first margin excision to completion/final reconstruction was 7 days (range 7-63 days). No local recurrences have been reported at a median follow-up of 14 months (range 1-36 months). This technique allows for careful margin analysis and subsequent central tumor excision with simultaneous reconstruction. This approach minimizes the need for a second major operation, which would have been necessary in 24% of our patients if treated by a one-stage excisional approach. It is noteworthy that 12% of MIS patients had invasive melanoma in the final excision specimen. This reinforces the importance of adequate full-thickness biopsies of suspicious pigmented lesions before any type of surgical management. With short follow-up, local control has been achieved by this technique in 100% of cases.

Full-thickness grafts procured from skin overlying the sentinel lymph node basin; reconstruction of primary cutaneous malignancy excision defects.

BACKGROUND: Radical excision of a cutaneous malignancy may require skin-graft closure. The skin overlying the sentinel lymph node (SLN) basin may be procured as a full-thickness skin graft (FTSG), eliminating a problematic and painful third wound, the donor site. However, the potential for implantation of malignant cells transferred from the nodal basin to the primary site, resulting in increased perigraft recurrence rates with the FTSG technique, has not been evaluated. METHODS: We retrospectively reviewed all patients with a cutaneous malignancy who underwent SLN biopsy and skin-graft closure to evaluate the outcomes of full-thickness sentinel node basin procured skin grafts compared with partial-thickness grafts (PTSG). RESULTS: Fifty-seven patients underwent FTSG reconstruction, and 39 patients had PTSG placed at the time of wide excision and SLN biopsy. Eighty-five percent of patients had melanoma; median melanoma thickness for FTSG patients (N = 53) was 2.0 vs. 2.8 mm (N = 29) for the PTSG group (P = .0007). Positive sentinel nodes were identified in nine of 57 patients (16%) and 11 of 39 patients (28%) in the FTSG and PTSG groups, respectively. Perigraft recurrence rates were not significantly different (5 vs. 10%) between the two groups. Graft take rate for the FTSG group was slightly higher than the PTSG group (median = 88% vs 80%, P = .008). FTSG cosmetic results were generally excellent. CONCLUSIONS: This FTSG closure method eliminates a painful third wound and often results in a better cosmetic outcome. Perigraft recurrences do not appear to be increased with FTSG. This technique should be in the armamentarium of surgeons who treat cutaneous malignancy.

Characterization of pulmonary cell growth parameters in a continuous perfusion microfluidic environment.

In vitro models of the alveolo-pulmonary barrier consist of microvascular endothelial cells and alveolar epithelial cells cultured on opposing sides of synthetic porous membranes. However, these simple models do not reflect the physiological microenvironment of pulmonary cells, wherein cells are exposed to a complex milieu of mechanical and soluble stimuli. In this report, we studied alveolar epithelial (A549) and microvascular endothelial (HMEC-1) cells within varying microfluidic environments as a first step towards building a microfluidic analog of the gas-exchange interface. We fabricated polydimethylsiloxane (PDMS) microdevices for parallel studies of cell growth under multiple flow rates. Cells adhered and proliferated in the microculture chambers for shear stresses up to approximately 2 x 10(-3) dynes/cm(2), corresponding to media turnover rates of approximately 53 seconds. Proliferation of these cells into confluent monolayers and expression of cell-specific markers (SP-A and CD-31) demonstrated successful pulmonary cell culture in microscale devices, a first for alveolar epithelial cells. These results represent the initial steps towards the development of microfluidic analogs of the alveolo-pulmonary barrier and tissue engineering of the lung.

Morphogenetic signals from chondrocytes promote chondrogenic and osteogenic differentiation of mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are potentially useful cells for musculoskeletal tissue engineering. However, controlling MSC differentiation and tissue formation in vivo remains a challenge. There is a significant need for well-defined and efficient protocols for directing MSC behaviors in vivo. We hypothesize that morphogenetic signals from chondrocytes may regulate MSC differentiation. In micromass culture of MSCs, incubation with chondrocyte-conditioned medium (CCM) significantly enhanced the production of cartilage specific matrix including type II collagen. In addition, incubation of MSCs with conditioned medium supplemented with osteogenic factors induced more osteogenesis and accumulation of calcium and increased ALP activity. These findings reveal that chondrocyte-secreted factors promote chondrogenesis as well as osteogenesis of MSCs during in vitro micromass culture. Moreover, when MSCs expanded with chondrocyte-conditioned medium were encapsulated in hydrogels and subsequently implanted into athymic mice, basophilic extracellular matrix deposition characteristic of neocartilage was evident. These results indicate that articular chondrocytes produce suitable morphogenetic factors that induce the differentiation program of MSCs in vitro and in vivo.

A microfluidic-FCS platform for investigation on the dissociation of Sp1-DNA complex by doxorubicin.

The transcription factor (TF) Sp1 is a well-known RNA polymerase II transcription activator that binds to GC-rich recognition sites in a number of essential cellular and viral promoters. In addition, direct interference of Sp1 binding to DNA cognate sites using DNA-interacting compounds may provide promising therapies for suppression of cancer progression and viral replication. In this study, we present a rapid, sensitive and cost-effective evaluation of a GC intercalative drug, doxorubicin (DOX), in dissociating the Sp1-DNA complex using fluorescence correlation spectroscopy (FCS) in a microfluidic system. FCS allows assay miniaturization without compromising sensitivity, making it an ideal analytical method for integration of binding assays into high-throughput, microfluidic platforms. A polydimethylsiloxane (PDMS)-based microfluidic chip with a mixing network is used to achieve specific drug concentrations for drug titration experiments. Using FCS measurements, the IC50 of DOX on the dissociation of Sp1-DNA complex is estimated to be 0.55 microM, which is comparable to that measured by the electrophoretic mobility shift assay (EMSA). However, completion of one drug titration experiment on the proposed microfluidic-FCS platform is accomplished using only picograms of protein and DNA samples and less than 1 h total assay time, demonstrating vast improvements over traditional ensemble techniques.

Sentinel node biopsy for thin melanomas: which patients should be considered?

BACKGROUND: As the incidence of melanoma increases, thin melanomas are being diagnosed at an increasingly frequent rate. Currently available prognostic factors are limited in their ability to reliably discriminate which patients will manifest regional nodal metastasis and would be identified early through sentinel node biopsy. METHODS: We summarized our experience with sentinel node biopsy for patients with cutaneous melanomas less than 1.00 mm in Breslow thickness, with evaluation of Clark level as a predictor of positive sentinel node metastasis. RESULTS: Among the 409 patients identified, micrometastases were found in the sentinel node in 20 patients, for an overall incidence of nodal progression of 4.9%. A total of 252 (62%) were Clark level II or III (11 of whom had a positive sentinel node) and 157 (38%) were Clark level IV (9 of whom had a positive sentinel node). We reviewed the literature to identify reliable indicators that might be helpful in determining which patients with "thin melanomas" would be likely to manifest regional progression to warrant routinely undergoing a preoperative lymphoscintigraphy followed by a sentinel node biopsy. CONCLUSIONS: Based on available data, patients with melanomas between 0.75 and 1.00 mm are appropriate candidates to be considered for sentinel node biopsy after discussing the likelihood of finding evidence of nodal progression, the risks of sentinel node biopsy (including the risk of a false-negative result), and the lack of proven survival benefit from any form of surgical nodal staging.