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Donald L Morton

Publications and source records attributed to Donald L Morton.

At least 19 recordsLinked to original sources
PubMed2006

Immunogenic gangliosides in human ovarian carcinoma.

Ganglioside signatures of four poorly and three moderately differentiated ovarian epithelial cancer (OEC) cell lines reveal the presence of GM3, GM2, GD2, O-AcGD2, GD1a and GM1b. The expression of GM3, presence of GD1a and GM1b in the ascitic fluid and plasma, together with a positive correlation in the total-gangliosides levels between ascitic fluid and plasma of OEC patients support the earlier contention that the tumor-gangliosides may be released (or shed) into the tumor-microenvironment. The immunogenicity of OEC-gangliosides is determined by comparing anti-ganglioside-IgM titers in ascitic fluid (n = 14) and plasma (n = 23) of OEC-patients and age-matched healthy (n = 14). The titers were measured by ELISA. Strikingly, the level of anti-GD1a-IgM is significantly higher in ascitic fluid and plasma of patients than in the plasma of healthy volunteers. Paired sample analysis of ascitic fluid and plasma from the same patients confirmed the significant expression of anti-GD1a IgM in OEC patients, while no such difference was observed with other anti-ganglioside IgMs among different groups. The significance of the endogenous IgM response to GD1a may be to eliminate this immunosuppressive-ganglioside from the tumor-microenvironment.

Ascitic Fluid↗
PubMed2006

Sentinel-node biopsy or nodal observation in melanoma.

BACKGROUND: We evaluated the contribution of sentinel-node biopsy to outcomes in patients with newly diagnosed melanoma. METHODS: Patients with a primary cutaneous melanoma were randomly assigned to wide excision and postoperative observation of regional lymph nodes with lymphadenectomy if nodal relapse occurred, or to wide excision and sentinel-node biopsy with immediate lymphadenectomy if nodal micrometastases were detected on biopsy. RESULTS: Among 1269 patients with an intermediate-thickness primary melanoma, the mean (+/-SE) estimated 5-year disease-free survival rate for the population was 78.3+/-1.6% in the biopsy group and 73.1+/-2.1% in the observation group (hazard ratio for recurrence[corrected], 0.74; 95% confidence interval [CI], 0.59 to 0.93; P=0.009). Five-year melanoma-specific survival rates were similar in the two groups (87.1+/-1.3% and 86.6+/-1.6%, respectively). In the biopsy group, the presence of metastases in the sentinel node was the most important prognostic factor; the 5-year survival rate was 72.3+/-4.6% among patients with tumor-positive sentinel nodes and 90.2+/-1.3% among those with tumor-negative sentinel nodes (hazard ratio for death, 2.48; 95% CI, 1.54 to 3.98; P<0.001). The incidence of sentinel-node micrometastases was 16.0% (122 of 764 patients), and the rate of nodal relapse in the observation group was 15.6% (78 of 500 patients). The corresponding mean number of tumor-involved nodes was 1.4 in the biopsy group and 3.3 in the observation group (P<0.001), indicating disease progression during observation. Among patients with nodal metastases, the 5-year survival rate was higher among those who underwent immediate lymphadenectomy than among those in whom lymphadenectomy was delayed (72.3+/-4.6% vs. 52.4+/-5.9%; hazard ratio for death, 0.51; 95% CI, 0.32 to 0.81; P=0.004). CONCLUSIONS: The staging of intermediate-thickness (1.2 to 3.5 mm) primary melanomas according to the results of sentinel-node biopsy provides important prognostic information and identifies patients with nodal metastases whose survival can be prolonged by immediate lymphadenectomy. (ClinicalTrials.gov number, NCT00275496 [ClinicalTrials.gov].).

Disease Progression↗
PubMed2006

Estrogen receptor-alpha methylation predicts melanoma progression.

The role of estrogen receptor alpha (ER-alpha) in melanoma is unknown. ER-alpha expression may be regulated in melanoma via hypermethylation of promoter CpG islands. We assessed ER-alpha hypermethylation in primary and metastatic melanomas and sera as a potential tumor progression marker. ER-alpha methylation status in tumor (n = 107) and sera (n = 109) from American Joint Committee on Cancer (AJCC) stage I to IV melanoma patients was examined by methylation-specific PCR. The clinical significance of serum methylated ER-alpha was assessed among AJCC stage IV melanoma patients receiving biochemotherapy with tamoxifen. Rates of ER-alpha methylation in AJCC stage I, II, and III primary melanomas were 36% (4 of 11), 26% (5 of 19), and 35% (8 of 23), respectively. Methylated ER-alpha was detected in 42% (8 of 19) of stage III and 86% (30 of 35) of stage IV metastatic melanomas. ER-alpha was methylated more frequently in metastatic than primary melanomas (P = 0.0003). Of 109 melanoma patients' sera in AJCC stage I, II, III, and IV, methylated ER-alpha was detected in 10% (2 of 20), 15% (3 of 20), 26% (5 of 19), and 32% (16 of 50), respectively. Serum methylated ER-alpha was detected more frequently in advanced than localized melanomas (P = 0.03) and was the only factor predicting progression-free [risk ratio (RR), 2.64; 95% confidence interval (95% CI), 1.36-5.13; P = 0.004] and overall survival (RR, 2.31; 95% CI, 1.41-5.58; P = 0.003) in biochemotherapy patients. Hypermethylated ER-alpha is a significant factor in melanoma progression. Serum methylated ER-alpha is an unfavorable prognostic factor.

Age Factors↗
PubMed2006

Melanoma patients with positive sentinel nodes who did not undergo completion lymphadenectomy: a multi-institutional study.

BACKGROUND: Completion lymph node dissection (CLND) is considered the standard of care in melanoma patients found to have sentinel lymph node (SLN) metastasis. However, the therapeutic utility of CLND is not known. The natural history of patients with positive SLNs who do not undergo CLND is undefined. This multi-institutional study was undertaken to characterize patterns of failure and survival rates in these patients and to compare results with those of positive-SLN patients who underwent CLND. METHODS: Surgeons from 16 centers contributed data on 134 positive-SLN patients who did not undergo CLND. SLN biopsy was performed by using each institution's established protocols. Patients were followed up for recurrence and survival. RESULTS: In this study population, the median age was 59 years, and 62% were male. The median tumor thickness was 2.6 mm, 77% of tumors had invasion to Clark level IV/V, and 33% of lesions were ulcerated. The primary melanoma was located on the extremities, trunk, and head/neck in 45%, 43%, and 12%, respectively. The median follow-up was 20 months. The median time to recurrence was 11 months. Nodal recurrence was a component of the first site of recurrence in 20 patients (15%). Nodal recurrence-free survival was statistically insignificantly worse than that seen in a contemporary cohort of patients who underwent CLND. Disease-specific survival for positive-SLN patients who did not undergo CLND was 80% at 36 months, which was not significantly different from that of patients who underwent CLND. CONCLUSIONS: This study underscores the importance of ongoing prospective randomized trials in determining the therapeutic value of CLND after positive SLN biopsy in melanoma patients.

Cohort Studies↗
PubMed2006

Microphthalmia transcription factor as a molecular marker for circulating tumor cell detection in blood of melanoma patients.

PURPOSE: Microphthalmia transcription factor (Mitf), which is important in melanocyte development and melanoma growth, was assessed using real-time quantitative reverse transcription-PCR assay to investigate its expression as a marker for circulating melanoma cells in blood and determine the correlation with disease stage and survival in melanoma patients. EXPERIMENTAL DESIGN: In optimization studies for Mitf, we tested 15 melanoma cell lines, 41 peripheral blood lymphocytes from healthy volunteers, and 21 metastatic melanoma tissues. Blood specimens were procured from 90 patients with stage I (n = 20), stage II (n = 20), stage III (n = 28), and stage IV (n = 22) melanoma. Blood specimens were also obtained at four bleed intervals from 58 patients enrolled in a prospective multicenter trial of biochemotherapy before and after surgical treatment of American Joint Committee on Cancer stage III melanoma. RESULTS: Under the optimized conditions, Mitf was negative in healthy peripheral blood lymphocytes and positive in all melanoma cell lines and 18 (86%) melanoma tissues. In the 90 patients, the rate of Mitf detection was higher with increasing American Joint Committee on Cancer stage (P < 0.0001). In the 58 patients treated with biochemotherapy and surgery, Mitf detection decreased with treatment (P = 0.019). Mitf detection after treatment was associated with a significantly lower relapse-free (P < 0.0001) and overall (P = 0.001) survival and was a significant independent prognostic factor for relapse-free (risk ratio, 5.63; P = 0.0004) and overall (risk ratio, 5.36; P = 0.005) survival. CONCLUSIONS: Mitf detection in blood can indicate subclinical metastatic disease and predict treatment outcome in melanoma patients.

Adolescent↗
PubMed2006

Prospective multicenter trial of staging adequacy in colon cancer: preliminary results.

HYPOTHESIS: Lymph node evaluation is an important prognostic factor in colorectal cancer (CRC). A 25% recurrence rate in patients with node-negative CRC suggests that current staging practices are inadequate. Focused analysis of the sentinel node (SN) by multiple sectioning and immunohistochemistry improves staging accuracy. DESIGN: Prospective phase 2 multicenter trial. SETTING: Tertiary referral cancer centers. PATIENTS: Between March 2001 and June 2005, 132 patients were enrolled with clinical stage I and II CRC in a prospective multicenter trial (R01-CA90484). INTERVENTION: During a standard oncologic resection, lymphatic mapping was performed and the SN identified either by the surgeon or the pathologist. Hematoxylin-eosin staining was performed on all lymph nodes and immunohistochemistry, on lymph nodes negative by hematoxylin-eosin staining. MAIN OUTCOME MEASURES: Micrometastases greater than 0.2 mm but less than 2 mm and isolated tumor cells less than 0.2 mm were defined according to the sixth edition of the American Joint Committee on Cancer Cancer Staging Manual. RESULTS: The 63 men and 69 women had a median age of 74 years. Sixty-eight patients (52%) underwent a right hemicolectomy; 3 (2.3%), a transverse colectomy; 9 (7%), a left colectomy; 15 (11%), a sigmoid colectomy; 34 (26%), a low anterior resection; 1 (1%), an abdominal perineal resection; and 2 (2%), a total colectomy. Of the 111 evaluable primary tumors, 19 (17%) were T1 lesions; 17 (15%), T2; 72 (65%), T3; and 3 (2.7%), T4 tumors. Thirty-three patients (30%) were classified as stage I; 46 (41%), stage II, and 32 (29%), stage III. The SN was identified by the surgeon in 127 patients (96%) and by the pathologist in 5 patients (4%). The median number of SNs and total lymph nodes examined were 3 and 14.5, respectively. The sensitivity of lymphatic mapping and SN analysis was 88.2% and the false-negative rate, 7.4% (6/81). Of the 6 false-negative results, 4 were attributed to lymphatic channels obliterated by tumor. Upstaging occurred in 28 patients (23.6%). CONCLUSIONS: In a multicenter trial, ultrastaging of colon cancer is feasible and accurate. In stage II CRC, 24% of patients had nodal carcinoma cells not detected by conventional staging methods. Surgical technique (adequate lymph node retrieval) and focused pathological analysis may improve staging accuracy and the selection of patients for chemotherapy. The unnecessary toxicity and expense of chemotherapy may be avoided in those patients who are truly node negative.

Aged↗
PubMed2006

Surgical management of the groin lymph nodes in melanoma in the era of sentinel lymph node dissection.

HYPOTHESIS: Intraoperative lymphatic mapping and sentinel lymphadenectomy (LM/SL) has become an increasingly popular surgical technique for staging the regional lymph nodes in early-stage melanoma. The technique of LM/SL has potentially great advantage for the groin, where the morbidity of superficial groin dissection or iliac dissection can be high. The surgical management of these basins is unknown for patients with tumor-positive sentinel lymph nodes (SNs). DESIGN: Cohort of successive patients undergoing LM/SL over 18 years. Those patients found to have tumor-positive SNs underwent sentinel complete lymph node dissection. Postoperatively, patients were followed up on a routine basis with serial examinations and chest radiography. The median follow-up was 50 months. SETTING: Tertiary cancer center. PATIENTS: The technique of LM/SL was performed for 431 consecutive patients. Sentinal lymph nodes were identified in each case. Patients with tumor-positive SNs underwent sentinel complete lymph node dissection. INTERVENTION: Cutaneous lymphoscintigraphy and blue dye with or without use of the gamma probe-directed LM/SL. Sentinel lymph nodes were examined by hematoxylin-eosin staining and immunohistochemistry staining with HMB-45 and S100 protein. Only patients with tumor-positive SNs had sentinel complete lymph node dissection. Main Outcome Measure Computer-assisted database with statistical analyses using log-rank tests and Cox regression models. RESULTS: Of the 431 patients, 264 (61%) were women and the median age was 50 years (age range, 15-89 years). A majority (86%) of the primary tumors were on the lower extremities, 54% were of Clark level IV or V, and there was a mean +/- SD thickness of 1.89 +/- 1.59 mm (range, 0.30-14.00 mm). Ninety-three patients (21%) were found to have tumor-positive SNs. After LM/SL and sentinel complete lymph node dissection, 62 patients (67%) were found to have a single tumor-positive lymph node, 25 (27%) had 2 tumor-positive lymph nodes, and 6 (6%) had 3 or more tumor-positive lymph nodes. Only 12 patients (4%) with tumor-negative SNs have had recurrence in the dissected basin. The 5-year overall survival was significantly better for patients with tumor-negative lymph nodes (mean +/- SD 5-year overall survival, 94% +/- 5%) than for patients with tumor-positive lymph nodes (mean +/- SD 5-year overall survival, 75% +/- 4%) (P < .01). The tumor status of the Cloquet lymph node was predictive of the tumor status of the iliac lymph nodes. Multivariate analyses with a Cox regression model identified tumor-positive SN (P = .001), primary tumor thickness (P = .03), and ulceration (P = .001) as being predictive of survival. Sex, age, Clark level, and primary site were not significant (P > .05). CONCLUSIONS: Our results demonstrate the prognostic significance of LM/SL for early-stage melanoma draining to the groin basin. The accuracy of LM/SL measured by the rare recurrences suggests that this surgical procedure should become standard for patients with early-stage melanoma of the lower extremities and trunk. Sampling of the Cloquet node should be used to determine the need for iliac dissection when a tumor-positive SN is identified in the groin.

Adolescent↗
PubMed2006

Immune responses in the draining lymph nodes against cancer: implications for immunotherapy.

Regional lymph nodes are the first site for melanoma metastases. The sentinel node (SN), on the direct lymphatic drainage pathway, which usually harbors first metastases, demonstrates significant suppression in its ability to respond to antigenic stimulation. This down-regulation of SN immunity is likely the basis of its susceptibility to tumor metastases, suggesting a potential role of the immune system in the control of malignant tumors. Despite immune dysfunction in the SN, phase II trials of systemic post-operative immunotherapy with a polyvalent melanoma vaccine developed at the John Wayne Cancer Institute showed improved 5-year overall survival in patients with melanoma metastatic to regional nodes. However, most immunotherapy clinical trials have failed to demonstrate a significant clinical response, and analyses of immune responses to tumor-associated antigens that correlate clinical responses have not been established. Therefore, refinements in assay methodologies and improvements in vaccine designs are critical to the success of cancer immunotherapy. Antigen presentation by dendritic cells (DCs) is the most potent means to initiate a T cell immunity. Dendritic cell-based immunotherapies have been vigorously attempted in the past decade. To improve the immunogenicity of cancer vaccines, we recently generated heterokaryons of DCs and tumor cells by electrofusion. The fusion hybrids retained their full antigen-presenting capacity and all natural tumor antigens. In pre-clinical animal experiments, a single injection of the DC-tumor fusion hybrids was sufficient to mediate the regression of tumors established in the lung, skin and brain. Most interestingly, successful therapy required the delivery of fusion hybrids directly into lymphoid organs such as lymph nodes. A clinical trial is now being carried out to test the immunogenicity and therapeutic effects of fusion hybrids for the treatment of metastatic melanoma.

Animals↗
PubMed2006

Chemokine receptor CXCR4 expression in patients with melanoma and colorectal cancer liver metastases and the association with disease outcome.

OBJECTIVE: To determine the role of chemokine receptor (CR) expression in patients with melanoma and colorectal cancer (CRC) liver metastases. SUMMARY BACKGROUND DATA: Murine and in vitro models have identified CR as potential factors in organ-specific metastasis of multiple cancers. Chemokines via their respective receptors have been shown to promote cell migration to distant organs. METHODS: Patients who underwent hepatic surgery for melanoma or CRC liver metastases were assessed. Screening cDNA microarrays of melanoma/CRC cell lines and tumor specimens were analyzed to identify CR. Microarray data were validated by quantitative real-time RT-PCR (qRT) in paraffin-embedded liver metastases. Migration assays and immunohistochemistry were performed to verify CR function and confirm CR expression, respectively. RESULTS: Microarray analysis identified CXCR4 as the most common CR expressed by both cancers. qRT demonstrated CXCR4 expression in 24 of 27 (89%) melanoma and 28 of 29 (97%) CRC liver metastases. In vitro treatment of melanoma or CRC cells with CXCL12, the ligand for CXCR4, significantly increased cell migration (P < 0.001). Low versus high CXCR4 expression in CRC liver metastases correlated with a significant difference in overall survival (median 27 months vs. 10 months, respectively; P = 0.036). In melanoma, low versus high CXCR4 expression in liver metastases demonstrated no difference in overall survival (median 11 months vs. 8 months, respectively; P = not significant). CONCLUSIONS: CXCR4 is expressed and functional on melanoma and CRC cells. The ligand for CXCR4 is highly expressed in liver and may specifically attract melanoma and CRC CXCR4 (+) cells. Quantitative analysis of CXCR4 gene expression in patients with liver metastases has prognostic significance for disease outcome.

Adult↗
PubMed2005

Survivin expression by metastatic melanoma predicts poor disease outcome in patients receiving adjuvant polyvalent vaccine.

Survivin and livin are members of the inhibitor of apoptosis protein (IAP) family. We hypothesized that elevated expression levels of these 2 IAP genes in resected advanced-stage metastatic melanoma lesions would be associated with poor disease outcome in patients receiving a polyvalent therapeutic cancer vaccine (Canvaxintrade mark). A quantitative real-time RT-PCR (qRT) assay for survivin and livin genes was used to assess mRNA expression in 63 metastatic melanomas obtained during cytoreductive surgery of American Joint Committee on Cancer (AJCC) stage IV melanoma. Nineteen of 63 metastatic melanoma patients received Canvaxin pre- and postoperatively, and 37 patients received only postoperative Canvaxin. Expression of survivin and livin protein was assessed by immunohistochemistry (IHC) and then correlated with mRNA. Survivin mRNA was detected in 62 of 63 (98%) melanoma specimens ranging from 0-5.96 x 10(4) mRNA copies of total RNA. Lower mRNA copy levels of survivin significantly correlated with improved overall survival among the 37 patients who received Canvaxin postoperatively but not preoperatively (log-rank test, p = 0.023). Among patients with low survivin mRNA copies, those who received postoperative Canvaxin did significantly better than patients who received pre- and postoperative Canvaxin (p = 0.003). Livin mRNA was detectable in 60 of 63 (95%) metastatic melanoma specimens but had no significant prognostic utility. These studies demonstrate that lower levels of survivin in recurrent metastatic melanomas are associated with significantly improved survival in patients receiving postoperative adjuvant immunotherapy. Overall, the study indicates survivin expression in metastatic melanomas can significantly influence disease outcome and patient responses to immunotherapy.

Adaptor Proteins, Signal Transducing↗
PubMed2005

Endogenous immune response to gangliosides in patients with confined prostate cancer.

Our study investigated whether endogenous IgM antibodies to gangliosides occur in patients with early stages of prostate cancer (CaP) patients, after defining ganglioside profiles of CaP cell lines. Immune and resorcinol staining detected the presence of gangliosides GM3, GM2, GD3, GD2 and GD1a but not GM1a, GD1b or GT1b in the extracts of normal prostatic epithelial cells (PrEC) and neoplastic androgen-insensitive (PC-3, DU145) and -sensitive (LNCaP-FGC and LNCaP-FGC-10) CaP cells. Using a sensitive ELISA, developed and validated in our laboratory, the titers of IgM against 8 gangliosides from sera of patients with benign prostatic hyperplasia (BPH) (n = 11), organ-confined (T1/T2, n = 36) and unconfined (T3/T4, n = 27) CaP and age-matched healthy men (n = 11) were determined double-blinded. Using ANOVA and Fisher's least significant difference (LSD) methods, the log-titers among different groups were compared. CaP patients differed from healthy and BPH patients in increased titers against GD1a and decreased titers against GD3. Titers of antibodies to other gangliosides exhibited no difference between CaP patients and others. The specific augmentation of anti-GD1a IgM in patients with organ-confined CaP (stage T1/T2) but not in patients with unconfined CaP (stage T3/T4) or BPH or in healthy controls is striking. This finding together with identification of GD1a as a major ganglioside in CaP cell lines and with the accruing studies on the immunosuppressive nature of GD1a indicates that augmentation of anti-GD1a IgM in confined CaP may signify an early endogenous immune response to eliminate a "danger signal" from tumor microenvironment and circulation.

Aged↗
PubMed2005

Sentinel lymphadenectomy does not increase the incidence of in-transit metastases in primary melanoma.

PURPOSE: Recent reports by European investigators suggest that sentinel lymphadenectomy (SLND), a mainstay of melanoma diagnosis and treatment planning, increases the risk of in-transit metastasis (ITM) and should be abandoned. This study compared the incidence of ITM after wide local excision (WLE), WLE plus SLND (SLND), or WLE plus elective lymphadenectomy (ELND) for primary melanoma. PATIENTS AND METHODS: Review of our prospective database identified 4,412 patients who underwent WLE (n = 2,771), SLND (n = 1,016), or ELND (n = 625) for stage I/II melanoma (1971 through 2002). The incidence of ITM overall and as a first recurrence was examined before and after computerized prognostic matching of treatment groups. Intergroup statistical comparisons used chi(2) analysis and log-rank test. RESULTS: The incidence of ITM increased with Breslow depth, Clark level, and T stage. Although overall incidence of ITM was significantly higher (P = .0008) after ELND (6.56%) versus WLE (3.36%) or SLND (3.64%), the ELND group had higher risk primaries. Treatment groups matched by T stage (1,875 patients; 625 per group) or by age, sex, Breslow depth, and primary location (1,680 patients; 560 per group), showed no significant differences in ITM overall or as a first recurrence. CONCLUSION: There is no relationship between SLND and ITM. Recent reports to the contrary reflect analysis of significantly smaller cohorts not matched for confounding variables such as T stage. The phase III Multicenter Selective Lymphadenectomy Trial will definitively settle the issue; until then, use of SLND, the most accurate staging procedure for early-stage melanoma, should continue.

Female↗
PubMed2005

Quantitative analysis of melanoma-induced cytokine-mediated immunosuppression in melanoma sentinel nodes.

PURPOSE: Melanoma sentinel nodes (SN) show evidence of immunosuppression prior to tumor metastasis. Interleukin (IL)-10 and IFN-gamma can induce dendritic cells (DC) that express immunosuppressive enzyme indoleamine 2,3-dioxygenase (IDO). The goals of this study are to evaluate the role of melanoma in SN immunosuppression and to assess reversibility of SN immunosuppression by a cytokine therapy. EXPERIMENTAL DESIGN: Fifty-seven clinical stage I/II melanoma patients underwent wide local excision and sentinel lymphadenectomy (WLE/SL), with removal of non-SN. In 21 patients, nodal RNA was analyzed by quantitative real-time PCR for expression levels of IL-2, IL-10, IL-12, IFN-gamma, and IDO genes. Among the remaining 36 patients, 15 received peritumoral injection of recombinant human granulocyte macrophage colony-stimulating factor (rhGM-CSF) 2 to 5 days prior to WLE/SL. Lymph nodes (LN) from these 36 patients were assessed for T-cell area, DC area, and DC density. RESULTS: Of 21 patients whose nodal RNA was analyzed, 13 had residual melanoma at the primary site or a tumor-positive SN. In these patients, expression levels of IL-10 (P = 0.05), IFN-gamma (P < 0.05), and IDO (P = 0.06) were dramatically higher in SNs than non-SNs. This difference was not evident in the 8 patients without residual melanoma or SN metastasis. Of the 36 patients whose LNs were examined for histologic features, the 15 patients who received rhGM-CSF had significantly higher SN values of T-cell area, DC area, and DC density than those who did not receive rhGM-CSF. CONCLUSIONS: Our data provide molecular evidence of cytokine-mediated SN immunosuppression that is associated with presence of melanoma. Furthermore, SN immunosuppression can potentially be reversed by a cytokine therapy.

Adult↗
PubMed2005

Melanoma recurrence patterns after negative sentinel lymphadenectomy.

HYPOTHESIS: A tumor-negative sentinel node (SN) does not eliminate the chance of melanoma recurrence. Patterns of metastasis can be identified and characterized in patients with tumor-negative SNs. DESIGN: Retrospective review. SETTING: Melanoma referral center. PATIENTS: Patients who underwent lymphatic mapping and sentinel lymphadenectomy between 1995 and 2002 and whose SNs were negative for metastasis by hematoxylin-eosin and immunohistochemistry staining were included in the study. The SN specimens from patients with recurrent disease were reexamined for missed metastasis. MAIN OUTCOME MEASURES: Differences in survival related to sites of recurrence and the rate of false-negative histopathologic SN diagnosis were determined. RESULTS: At a median follow-up of 36.7 months, 69 (8.9%) of 773 patients with tumor-negative SNs had recurrent disease. Three-year survival after first recurrence was 17.1% in the 37 patients with distant recurrence, 48.7% in the 19 patients with local or in-transit recurrence, and 63.5% in the 13 patients with regional basin recurrence; the difference in survival between patients with local or regional and distant recurrences was statistically significant (P<.001). Histopathologic reexamination of SNs from the 69 patients identified 9 patients with false-negative SNs; 2 of these had same-basin recurrences. CONCLUSIONS: The SN is a valuable prognostic indicator because only 8.9% of patients with tumor-negative SNs will develop recurrence. The low incidence (1.7%) of regional basin recurrence in patients with negative SNs supports the accuracy of our current method of lymphatic mapping and sentinel lymphadenectomy to identify occult regional nodal basin metastasis.

Adolescent↗
PubMed2005

Sentinel node biopsy for early-stage melanoma: accuracy and morbidity in MSLT-I, an international multicenter trial.

OBJECTIVE: The objective of this study was to evaluate, in an international multicenter phase III trial, the accuracy, use, and morbidity of intraoperative lymphatic mapping and sentinel node biopsy (LM/SNB) for staging the regional nodal basin of patients with early-stage melanoma. SUMMARY BACKGROUND DATA: Since our introduction of LM/SNB in 1990, this technique has been widely adopted and has become part of the American Joint Committee on Cancer (AJCC) staging system. Eleven years ago, the authors began the international Multicenter Selective Lymphadenectomy Trial (MSLT-I) to compare 2 treatment approaches: wide excision (WE) plus LM/SNB with immediate complete lymphadenectomy (CLND) for sentinel node (SN) metastases, and WE plus postoperative observation with CLND delayed until the subsequent development of clinically evident nodal metastases. METHODS: After each center achieved 85% accuracy of SN identification during a 30-case learning phase, patients with primary cutaneous melanoma (> or =1 mm with Clark level > or =III, or any thickness with Clark level > or =IV) were randomly assigned in a 4:6 ratio to WE plus observation (WEO) with delayed CLND for nodal recurrence, or to WE plus LM/SNB with immediate CLND for SN metastasis. The accuracy of LM/SNB was determined by comparing the rates of SN identification and the incidence of SN metastases in the LM/SNB group versus the subsequent development of nodal metastases in the regional nodal basin of those patients with tumor-negative SNs. Early morbidity of LM/SNB was evaluated by comparing complication rates between the 2 treatment groups. Trial accrual was completed on March 31, 2002, after enrollment of 2001 patients. RESULTS: Initial SN identification rate was 95.3% overall: 99.3% for the groin, 95.3% for the axilla, and 84.5% for the neck basins. The rate of false-negative LM/SNB during the trial phase, as measured by nodal recurrence in a tumor-negative dissected SN basin, decreased with increasing case volume at each center: 10.3% for the first 25 cases versus 5.2% after 25 cases. There were no operative mortalities. The low (10.1%) complication rate after LM/SNB increased to 37.2% with the addition of CLND; CLND also increased the severity of complications. CONCLUSIONS: LM/SNB is a safe, low-morbidity procedure for staging the regional nodal basin in early melanoma. Even after a 30-case learning phase and 25 additional LM/SNB cases, the accuracy of LM/SNB continues to increase with a center's experience. LM/SNB should become standard care for staging the regional lymph nodes of patients with primary cutaneous melanoma.

Adolescent↗
PubMed2005

Human antiganglioside autoantibodies: validation of ELISA.

Gangliosides have a hydrophilic sugar chain that contains antigenic determinants and a hydrophobic ceramide. In humans, gangliosides elicit a T-cell independent IgM response; antiganglioside IgM autoantibodies may be pentameric or polymeric. A correlation between specific neuropathies and antiganglioside autoantibodies has been confirmed. Although many neurologists attempt to lower titers of antiganglioside autoantibodies, oncologists are developing strategies to augment production of IgM antibodies that will remove immunosuppressive gangliosides from the circulation of patients and target gangliosides and kill tumor cells. Antiganglioside IgM antibodies can cause leakage of the blood-nerve barrier in a concentration-dependent and complement-independent manner, bind to neuronal gangliosides to create a neuromuscular block and serve as a marker of axonal damage in neuropathies such as multiple sclerosis. They are also a promising biomarker of early prostate cancer. There is a need to validate the protocol for enzyme-linked immunosorbent assay (ELISA) of antiganglioside IgM autoantibodies. This validation must consider the purity of gangliosides from different commercial sources, the coating of gangliosides onto a solid matrix in a manner that maximizes exposure of oligosaccharide epitopes to IgM paratopes, techniques to minimize background noise and eliminate nonspecific antibody binding, and carefully defined positive and negative controls. The validated protocol also must include a simple formula to estimate titers for several replicas. Finally, antibody titers must be converted to natural logs for statistical appraisal.

Autoantibodies↗