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Biomedical subjects

D L Morton

Publications and source records attributed to D L Morton.

At least 55 records · Page 3Linked to original sources
PubMed2000

Functional interleukin 4 receptor and interleukin 2 receptor common gamma-chain on human non-small cell lung cancers: novel targets for immune therapy.

OBJECTIVE: The interleukin 4 receptor has been demonstrated on the surface of human non-small cell lung carcinoma cell lines and tumor specimens. Interleukin 4 causes G1-phase cell-cycle arrest of non-small cell lung cancer cell lines expressing the interleukin 4 receptor; the effect directly correlates with the expression of the interleukin 4 receptor and is seen within 48 hours after treatment. We examined signal transduction pathways used by the interleukin 4 receptor that may account for growth arrest of the cell line LUst but had no effect on another non-small cell lung cancer cell line, SK-MES-1. METHODS: Western blot analysis was performed on both LUst and SK-MES-1 cell lines cultured in the presence of interleukin 4 (500 U/mL). Cells were lysed, protein extracted, and electroblotted; blots were then probed with murine monoclonal antibodies to specific intracellular proteins. RESULTS: Western blotting of the cell lines with antiphosphotyrosine antibody (4G10) demonstrated multiple (140 kd, 100-130 kd, and 65 kd) phosphoproteins seen only in the interleukin 4-treated LUst cell line and not observed in the SK-MES-1 cell lines. Immunoprecipitation and blotting of the LUst cell line with specific secondary antibodies demonstrated that the 140-kd phosphoprotein was the interleukin 4 receptor, the 130-kd phosphoprotein was Janus kinase 1, the 116-kd phosphoprotein was Janus kinase 3, and the 65-kd phosphoprotein was the interleukin 2 receptor gamma-chain. Specific binding was not observed in the non-small cell lung cancer cell line SK-MES-1, suggesting that a functional interleukin receptor gamma-chain was not present. Southern blotting with complementary DNA probes to interleukin 2 receptor gamma-chain confirmed the absence of this receptor on cell line SK-MES-1. CONCLUSIONS: These results suggest that non-small cell lung cancer cells may express functional cytokine receptors, including the interleukin 2 receptor gamma-chain commonly found in association with the lymphocyte interleukin 2 receptor. These receptors may be novel targets for directing cytokine-based immune therapy.

Carcinoma, Non-Small-Cell Lung↗
PubMed2000

Individualized prognosis for melanoma patients.

The clinical course of malignant melanoma is notoriously variable. Current approaches to prognostication allow assignment to risk categories but do not permit accurate assessment of prognosis on an individual patient basis. We analyzed a melanoma histology database that comprises 1,042 sequential melanoma patients evaluated by A.J.C. at UCLA between 1980 and 1990 for 30 separate variables according to a standard protocol. After censoring for absent data, a univariate Cox model analysis was performed that showed 20 individual variables that were significantly linked to clinical outcome. A step-up multivariate analysis was then performed. The combined analysis shows 5 variables: gender, site of primary, age relative to 60 years, Breslow thickness, and presence and width of ulceration to be linked to survival. Probability of survival is calculated using a 2-step approach. The survival-linked variables are multiplied to give an individualized risk score. This is converted into probability of survival by the formula .987 (risk score) for 3-year survival, .975 (risk score) for 5-year survival, and .960 (risk score) for 10-year survival. Thus, a 55-year-old woman with a 1.8-mm nonulcerated melanoma on the leg would have a risk score of (1 x 1 x 1 x 2 x 1) = 2 and a predicted probability of survival at 5 years of .9752 (95%) and at 10 years of .9602 (92%). We used similar techniques to develop individualized risk scores for likelihood of recurrence. The significant variables in this case are anatomic site of the primary melanoma, melanoma subtype, Breslow thickness, and presence and width of ulceration. The formulae for likelihood of recurrence at different periods after initial surgical removal of the primary melanoma are at 3 years, .979(risk score); at 5 years, .971(risk score); and at 10 years, .957(risk score). This relatively simple approach to prognostication uses readily available demographic information and is likely to be more accurate than single-factor analysis.

Adult↗
PubMed2000

Judging the therapeutic value of lymph node dissections for melanoma.

BACKGROUND: The management of the regional lymph nodes remains controversial for early-stage melanoma and for those patients with lymph node metastases; American Joint Committee on Cancer stage III. This study examines the importance of quality of the surgical resection measured by the extent of lymph node dissection (quartile of the total number of lymph nodes removed) to determine if this factor is an important prognostic factor for survival. STUDY DESIGN: We reviewed our computer-assisted database of more than 8,700 melanoma patients prospectively collected from 1971 through the present to identify patients who underwent lymph node dissection for stage III melanoma. We included only patients who had their nodal dissections performed at our institute. Patients who underwent sentinel lymph node dissection were excluded. These patients were then analyzed as a group and by individual lymphatic basins: cervical, axillary, and inguinal basins. Univariate and multivariate analyses were used to examine the model that included tumor burden, thickness of the primary melanoma, gender, age, clinical status of the lymph nodes (palpable versus not palpable), and the primary site. The survival and recurrence rates were analyzed using the Cox proportional hazards model. RESULTS: Five hundred forty-eight patients underwent regional lymph node dissections. Of these patients, 214 underwent axillary dissections, 181 inguinal dissections, and 153 cervical dissections. The extent of the nodal dissections was based on the quartile of nodes excised, ranging from 1 to 98 (mean +/- SD = 25.8 +/- 15.8). Patients were stratified by tumor burden and quartile of number of lymph nodes removed. The overall 5-year survival of patients with four or more lymph nodes having tumor and the highest quartile of lymph nodes removed was 44% and was 23% for the lowest quartile of total lymph nodes excised (p = 0.05). By univariate analysis, tumor burden (p = 0.0001), quartile of total lymph nodes removed (p = 0.043), and primary site (p = 0.047) were statistically significant for predicting overall survival. Gender, clinical status of the nodes, primary tumor thickness, age, and dissected basin were not significant (p > 0.05). By multivariate analysis only the tumor burden (p = 0.0001) and quartile of lymph nodes resected (p = 0.044) were statistically significant. CONCLUSIONS: The extent of lymph node dissection for melanoma when analyzed by quartiles is an independent factor in overall survival. This factor appears to be more important with increasing tumor burden in the lymphatic basin. The extent of lymph node dissection should be considered as a prognostic factor in the design of clinical trials that involve stage III melanoma.

Female↗
PubMed2000

Standardized probe-directed sentinel node dissection in melanoma.

BACKGROUND: Radiopharmaceutical agents appear to improve the accuracy of sentinel node (SN) identification in patients with early-stage melanoma, but the optimal radiopharmaceutical agent and its timing from injection to surgery remain controversial. We undertook this investigation to examine the utility of 3 methods of intraoperative lymphatic mapping with radiopharmaceutical-directed sentinel lymphadenectomy (LM/SL). We suspected that concurrent injection of radiopharmaceutical and blue-dye would lead to the greatest success of SN identification. METHODS: The study was composed of 247 consecutive patients who had American Joint Committee on Cancer stage I or II melanoma. Before LM/SL, all patients underwent cutaneous lymphoscintigraphy by 1 of 3 techniques: technetium 99m (Tc 99m) human serum albumin (HSA) injected at least 24 hours before LM/SL (124 patients), Tc 99m filtered sulfur colloid (SC) injected no more than 4 hours before LM/SL (same-day SC, 95 patients), or Tc 99m SC injected at least 18 hours before LM/SL (prior-day SC, 28 patients). At the time of LM/SL, isosulfan blue dye was injected alone (SC groups) or with a second dose of HSA (HSA group). A hand-held gamma probe was used to determine the radioactive (hot) counts of blue-stained and nonstained nodes, and the in vivo and ex vivo node-to-background count ratios of the nodes were compared. RESULTS: Preoperative LS identified 299 drainage basins; LM/SL identified at least 1 SN in 119 (98%) of 121 basins using same-day SC, 142 (97%) of 146 basins using HSA, and 32 (100%) of 32 basins using prior-day SC. There was no difference (P = .62) in the accuracy rate between the 3 techniques. The total number of SNs was 463. Same-day SC yielded higher intraoperative node-to-background count ratios than did either of the other techniques (P < .0001). Same-day SC also had the greatest relative change in radioactivity between the blue sentinel node and the post-excision basin (P < .0001), and the highest rate of SNs that were both blue and hot (in vivo or ex vivo ratio > or = 2, P = .05). CONCLUSIONS: LS and LM/SL performed on the same day with a single injection of filtered Tc 99m SC serves as the most useful method for probe-directed LM/SL. This technique demonstrated the highest in vivo and ex vivo count ratios, fall-off of radioactivity between the excised nodes and post-excision basin, and concordance between blue dye and hot nodes. It should be recommended as the method of choice for probe-directed LM/SL.

Humans↗
PubMed2000

Focused examination of sentinel lymph nodes upstages early colorectal carcinoma.

Approximately 30 per cent of patients with early colorectal carcinoma (CRC) develop systemic disease. A subgroup of these patients may harbor occult micrometastatic disease and might benefit from adjuvant chemotherapy. We investigated sentinel lymph node (SLN) mapping and focused pathologic examination of the SLN as a means of detecting nodal micrometastases. Between 1996 and 2000 SLN mapping was performed in 50 consecutive patients undergoing colectomy for CRC. All lymph nodes in the resection specimen were examined via routine hematoxylin and eosin (H&E) staining. In addition multiple sections of each SLN were examined via both H&E and cytokeratin immunohistochemistry. At least one SLN was identified in 47 patients (94%). In seven patients (14%) SLN mapping identified aberrant drainage that altered the planned resection. The SLN(s) correctly predicted nodal basin status in 44 of 47 (94%) cases; there were three falsely negative SLNs. Sixteen cases had positive SLNs by conventional H&E staining. An additional 10 (20%) cases were upstaged by a focused examination of the SLNs. Micrometastases were identified in three cases by H&E staining of multiple sections of the SLN and in seven only by cytokeratin immunohistochemistry. In nine cases the SLN was the only node containing tumor cells. In this study, SLN mapping demonstrated aberrant nodal drainage patterns that altered the surgical resection in patients with CRC. Focused examination of SLNs may detect micrometastases missed by conventional techniques and thereby identify patients who might benefit from adjuvant therapy.

Adult↗
PubMed2000

Immunology of gangliosides.

This review discusses the immunology of gangliosides from the perspective of tumor, neuronal and general immunology. Antiganglioside antibodies in human sera are invariably IgM and are found in healthy individuals. Their titers decline with age. Persistent high titer of IgM is associated with several diseases, particularly neuropathies. Membrane-bound gangliosides are important tumor-associated antigens and targets for immune attack. Cells enriched with gangliosides can be used as cancer vaccines. Efficacy of these vaccines depends on the viability of whole cells, integrity of the cell membranes, adjuvants and topography of the tumor-associated antigens. The role of antiganglioside IgM is to eliminate the immunosuppressive gangliosides shed from tissues during ageing, degeneration of neural and extraneural tissues, and tumor growth and necrosis. In addition, in vitro observations with human and murine monoclonal antibodies suggest that they are capable of complement dependent cytotoxicity and apoptosis.

Animals↗
PubMed1999

Active specific immunotherapy with polyvalent melanoma cell vaccine for patients with in-transit melanoma metastases.

BACKGROUND: This study was conducted to document the rate, duration, and type of objective response to active specific immunotherapy with a polyvalent melanoma cell vaccine (PMCV) for patients with in-transit melanoma metastases and to identify any acute or chronic toxic effects of PMCV treatment. METHODS: An analysis was conducted of all in-transit melanoma patients seen at the John Wayne Cancer Institute in Santa Monica, California, during the period 1985-1997 who were enrolled in prospective PMCV protocols in the absence of other therapies with possible antitumor activity (n = 54). Clinical response to PMCV was assessed by standard criteria. Survival curves were estimated by the Kaplan-Meier method. Toxicity was graded according to the Eastern Cooperative Oncology Group standard. RESULTS: PMCV produced a 17% (9 of 54 patients) objective response rate with a 13% rate (7 of 54 patients) of complete remission (CR). The median duration of CR was >22 months. Complete response lasting more than 1 year was observed in 4 patients (7.2%); 1 patient remained in remission over 9 years. Median survival was >53 months (i.e., not reached) for responders, 42 months for nonresponders, and 53 months overall. Salvage interventions allowed reinduction with PMCV in 23 of 25 patients, who subsequently remained clinically free of disease for a median of 14 months. Overall toxicity was mild, easily tolerable, and did not significantly change the quality of life. There were no toxic deaths. CONCLUSIONS: PMCV can cause objective complete regression of measurable intransit metastatic melanoma with minimal toxicity, and may prolong patients' median survival.

Cancer Vaccines↗
PubMed1999

Plasma DNA microsatellites as tumor-specific markers and indicators of tumor progression in melanoma patients.

Multiple DNA microsatellites with frequent loss of heterozygosity (LOH) in melanomas have been demonstrated. The finding that free DNA is enriched in blood of melanoma patients prompted studies to determine whether tumor-specific DNA, such as DNA microsatellites exhibiting LOH, can be detected in blood and have clinical use. In this study, 57 advanced and 19 early clinically staged melanoma patients were assessed using 10 microsatellite markers on six chromosomes. Matched plasma and melanoma tissues from 40 patients showed significant concordance of LOH (P < 0.0001). The frequency of LOH microsatellite markers detected in plasma significantly increased in more advanced-staged patients. At locus D3S1293, LOH detection showed significant correlation to clinical disease progression (P = 0.02). Additionally, the combination of LOH microsatellite markers D9S157 and D3S1293 (P = 0.01), D9S157 and D1S228 (P = 0.05), and D11S925 and D3S1293 (P = 0.01) were significantly correlated to progression of different clinical stages of disease. These studies indicate that tumor-specific LOH markers in plasma have a potential clinical use as diagnostic and prognostic markers in melanoma patients.

Adult↗
PubMed1999

Survival of patients with melanoma of the lower extremity decreases with distance from the trunk.

BACKGROUND: Early stage melanoma of the lower extremity is generally associated with a favorable prognosis. However, several retrospective studies have suggested that melanoma on the foot portends poor survival. The authors hypothesized that the region of the lower extremity has prognostic importance. METHODS: Between January 1, 1971, and December 31, 1991, 652 patients were seen at the John Wayne Cancer Institute for a primary melanoma on the foot (92 patients), calf (336 patients), or thigh (224 patients). All patients had clinically or histopathologically negative regional lymph nodes. The duration of follow-up after first diagnosis was 9 -302 months, with a minimum of 6 years for survivors. Survival curves were estimated by the Kaplan-Meier method. Pearson chi-square test was used to test differences associated with the regional site of the lower-extremity melanoma. The log rank test was used for univariate analysis, and Cox proportional hazards regression was used for multivariate analysis. RESULTS: Univariate analysis identified regional site, gender, Breslow depth, Clark level, and age at diagnosis as significant for both overall survival (OS) and disease free survival (DFS) (P = 0.0001). Multivariate analysis confirmed regional site as an independent prognostic variable for OS (P = 0.0002) and DFS (P = 0.0005). Ten-year rates of OS and DFS were 71% and 66%, respectively, for patients with foot melanomas, compared with 92% and 87% for those with calf melanomas and 95% and 94% for those with thigh melanomas. CONCLUSIONS: The prognosis for patients with primary melanoma of the lower extremity is affected by the distance of the lesion from the trunk. Thus, distal (foot) lesions carry a higher risk than thigh lesions. This difference should be considered as a covariate when stratifying patients in clinical trials.

Adult↗
PubMed1999

Metastasectomy for recurrent stage IV melanoma.

BACKGROUND AND OBJECTIVES: Many patients undergoing complete surgical resection of distant metastatic melanoma (American Joint Committee on Cancer [AJCC] stage IV) develop recurrent disease. We examined whether a second metastasectomy could prolong the survival of patients with recurrent stage IV melanoma. DESIGN AND PATIENTS: Retrospective review of our 8,750-patient melanoma database identified 211 patients who were rendered clinically free of disease by surgical resection of stage IV metastases during the 24-year study period (January 1971 through December 1995). Our study population comprised the 131 patients who developed recurrent stage IV disease and were followed for at least 24 months or until death. RESULTS: The median disease-free interval prior to recurrent stage IV disease was 8 months (range 0.6-91.8 months). There were 131 tumor-involved anatomic sites; the median number was one (range 1-3). Of these sites, 71 (54.2%) were soft tissue, 35 (26.7%) were pulmonary, 28 (21.4%) were gastrointestinal, 23 (17.6%) were cerebral, 13 (9.9%) were skeletal, and 2 (1.5%) were gynecologic. Median survival following treatment for recurrent stage IV melanoma was 18.2 months after complete metastasectomy, compared with 12.5 months or 5.9 months after a palliative surgical procedure or nonsurgical management, respectively. The 5-year survival rate was 20.0% (8/40) for patients in the complete surgical metastasectomy group, compared with 7.0% (3/43) and 2.1% (1/48) for those in the palliative surgical and nonsurgical groups, respectively. By multivariate analysis, the two most important prognostic factors for survival following diagnosis of recurrent stage IV melanoma were a prolonged disease-free interval to recurrence (P = 0.0001) and complete surgical metastasectomy of the recurrence (P = 0.0001). CONCLUSIONS: Metastasectomy can prolong the survival of patients with recurrent stage IV melanoma if all clinically evident tumor can be resected.

Adult↗
PubMed1999

Lymph node biopsy does not impair survival after therapeutic dissection for palpable melanoma metastases.

BACKGROUND: To determine the effects of disrupting a nodal basin in patients with American Joint Committee on Cancer stage III melanoma with clinically palpable lymph nodes, we studied patients who underwent therapeutic lymph node dissection after excisional lymph node biopsy, after fine-needle aspiration (FNA) biopsy, or without a preoperative biopsy. METHODS: We performed a retrospective review of our patients with American Joint Committee on Cancer stage III melanoma who were treated between January 1972 and June 1995, using data acquired from our 8200-patient database. The study group included 670 patients with melanoma, with known primary tumors, who underwent therapeutic lymph node dissection for palpable nodal metastases diagnosed by open biopsy (227 patients), by FNA (66 patients), or by clinical observation without biopsy (377 patients). Regional node recurrence, 5-year disease-free survival, and overall survival rates were calculated. RESULTS: The same-basin regional node recurrence rates were similar for the three groups (open biopsy, 4.6%; FNA, 3.2%; no biopsy, 4.6%; P = .14). The 5-year disease-free survival rates were 36.8% for the open-biopsy group, 29.6% for the FNA group, and 28.9% for the no-biopsy group (P = .08); corresponding 5-year overall survival rates were 40.6%, 43.9%, and 36.1%, respectively (P = .18). Multivariate analysis failed to identify preoperative biopsy as a significant risk factor. Matched-pair analysis using age, gender, primary tumor site, Breslow thickness, and tumor burden showed no differences in the 5-year disease-free survival rates (33% for the open-biopsy group vs. 27% for the FNA and no-biopsy groups, P = .42) and the 5-year overall survival rates (41% vs. 35%, P = .32). CONCLUSIONS: For patients with melanoma with palpable regional adenopathy, histological confirmation of clinical suspicion with either FNA or excisional lymph node biopsy does not adversely affect survival or recurrence rates.

Biopsy↗
PubMed1999

Parotid region lymphatic mapping and sentinel lymphadenectomy for cutaneous melanoma.

BACKGROUND: Routine elective superficial parotidectomy for patients with primary cutaneous melanomas of the scalp, auricle, or face has been questioned. We evaluated an alternative, i.e., lymphatic mapping and sentinel lymphadenectomy, for patients with primary cutaneous melanomas draining to the region of the parotid gland. PATIENTS: Retrospective review of our large (>8000 patients) melanoma database identified 39 patients with primary melanomas (American Joint Committee on Cancer stage I or II) of the scalp (n = 19), auricle (n = 11), or face (n = 9) who underwent intraoperative lymphatic mapping to identify a sentinel node (SN) in the region of the parotid gland, between June 1985 and July 1997. RESULTS: A SN was identified in the parotid region of 37 patients (94.9%), four of whom had SN metastases. The mean number of SN obtained was 2.3/patient (range, 1-4/patient). The two patients (5.1%) for whom a parotid-region SN could not be identified underwent superficial parotidectomy during the same operation. Among the 33 patients with tumor-free SN, with a median follow-up period of 33.2 months (range, 1-121 months), there was one (3.1%) intraparotid recurrence; thus, the false-negative rate was 3.1%. The procedure-related surgical morbidity rate was only 2.6% (one case of temporary facial nerve paresis). CONCLUSIONS: For patients with primary melanomas of the scalp, auricle, or face, sentinel lymphadenectomy can be performed accurately in the parotid region and offers a low-morbidity alternative to routine elective superficial parotidectomy.

Adult↗
PubMed1999

Lymphatic mapping and sentinel lymphadenectomy after wide local excision of primary melanoma.

BACKGROUND: Lymphatic mapping and sentinel lymphadenectomy (LM/SL) are generally avoided in patients who have already undergone wide local excision (WLE) of a primary melanoma, because of concern that disruption of the cutaneous lymphatics might alter lymphatic flow to the sentinel node. We reviewed carefully chosen patients who had undergone LM/SL after WLE to identify circumstances that might make this approach otherwise safe and clinically accurate. STUDY DESIGN: From our melanoma database of 8,300 patients, of whom 1,015 had undergone LM/SL, we retrospectively identified 47 patients who had previously undergone WLE. Patient and tumor characteristics were collected and compared with followup data from clinic files. RESULTS: Median WLE surgical margins before LM/SL were 2.0 cm and most patients had extremity lesions. Eleven of the 47 patients (23%) had tumor-involved sentinel nodes, and 8 of these patients (73%) had a solitary nodal metastasis. With a median followup period of 36 months, 3 sentinel node-negative patients developed nodal recurrences. Two of these patients had positive sentinel nodes on pathology re-review and were not considered failures of the lymphatic mapping surgical procedure. The third patient developed in-transit metastases and delayed nodal recurrence. An additional patient, who had a primary tumor on the trunk, developed a nodal recurrence in the basin opposite that identified by lymphoscintigraphy. The overall error rate of the technique was 4 in 36 (11%). This included 2 pathology misdiagnoses (5.6%), 1 nodal recurrence associated with in-transit regional metastases (2.8%), and 1 lymphatic mapping error (2.8%). CONCLUSIONS: LM/SL can be cautiously performed in patients who have undergone previous WLE if the primary resection margin was no greater than 2.0 cm and the primary was not in a region of ambiguous drainage. Lymphatic mapping may be inaccurate when melanomas have been resected with large margins, especially if the wound was closed with rotation flaps, and when melanomas are on the head and neck or trunk regions.

Adult↗
PubMed1999

IgM anti-ganglioside antibodies induced by melanoma cell vaccine correlate with survival of melanoma patients.

Melanoma cells express ganglioside antigens GM3, GD3, GM2, and GD2 on their surface. This study examined whether immunization with a melanoma cell vaccine induced anti-ganglioside antibody responses in melanoma patients and whether these responses were correlated with survival. Sixty-six patients who had received melanoma cell vaccine immunotherapy after surgical removal of regional metastatic melanoma were identified. Cryopreserved serum samples from these patients were used in an enzyme-linked immunsorbent assay to determine the IgM antibody levels to GM2, GD2, GM3, and GD3 prior to melanoma cell vaccine treatment and 4 wk after the first melanoma cell vaccine immunization. All antibody levels significantly increased by week 4 (p < 0.001 for all four antibodies) and all increases were significantly associated with survival (anti-GD2, p < 0.001; anti-GM2, p = 0.001; anti-GD3, p < 0.001; anti-GM3, p < 0.001). Anti-tumor activity of these antibodies was proved using five representative antibody-positive sera in a complement-dependent cytotoxicity assay with cultured melanoma cell lines. These studies suggest that GM2, GD2, GM2, and GD3 expressed by melanoma cells can induce specific IgM antibodies and that high levels of these antibodies might have a beneficial impact on survival.

Antibodies, Anti-Idiotypic↗
PubMed1999

Carbon dye as an adjunct to isosulfan blue dye for sentinel lymph node dissection.

BACKGROUND: The success of intraoperative lymphatic mapping depends on accurate identification of the sentinel node. We hypothesized that a carbon particle suspension would allow histopathologic confirmation of the sentinel lymph node through deposition of carbon within that node. METHODS: An animal model was used to compare the lymphatic mapping accuracy of carbon dye with that of isosulfan blue dye, the standard agent for intraoperative visualization of the sentinel lymph node. Twenty-two rats underwent lymphatic mapping in each distal lower extremity with various combinations of carbon dye and isosulfan blue dye. All stained (blue or black) nodes in the inguinal drainage basin were removed for pathologic analysis, including carbon particle analysis. A meticulous search identified all nonstained (nonsentinel) nodes in the same basin. These nonsentinel nodes were examined for carbon particles by light microscopy. Dermal diffusion of mapping agents at the injection site was also recorded. Animals were then observed for 28 days to assess the toxicity of mapping agents. RESULTS: Although isosulfan blue dye and full-strength carbon dye each stained all sentinel nodes, the latter obscured histologic detail. The combination of 2.5% carbon dye, 7.5% saline solution, and 90% isosulfan blue dye also stained all sentinel nodes; carbon particles were seen on light microscopy in all 13 stained nodes and did not interfere with histologic evaluation. No unstained node contained carbon particles, although the number of nonsentinel nodes was small. Carbon dye exhibited significantly less intradermal diffusion than isosulfan blue dye, but the carbon left a permanent mark on the skin. No toxicity or side effect associated with the use of carbon dye was observed. CONCLUSION: Carbon dye allows histopathologic confirmation of sentinel lymph nodes identified by isosulfan blue dye.

Animals↗