Multimarker reverse transcriptase-polymerase chain reaction assay in lymphatic drainage and sentinel node tumor burden.

PURPOSE: We assessed molecular (presence of melanoma cells markers in lymph fluid [LY]) and pathological features (sentinel lymph node [SN] tumor burden according to Rotterdam criteria, metastases microanatomic location) and correlated them with survival and melanoma prognostic factors in a group of patients with positive SN biopsy. METHODS: We analyzed 368 consecutive SN-positive patients after completion lymph node dissection (CLND). In 321 patients we obtained data on SLN microanatomic location/tumor burden (only 7 cases had metastases <0.1 mm); in 137 we additionally analyzed 24-hour collected LY after CLND (multimarker reverse transcriptase-polymerase chain reaction [MM-RT-PCR] with primers for tyrosinase, MART1 (MelanA), and uMAGE mRNA (27.7% positive samples)]. Median follow-up time was 41 months. RESULTS: According to univariate analysis, the following factors had a negative impact on overall survival (OS): higher Breslow thickness (P = .0001), ulceration (P < .0001), higher Clark level (P = .008), male gender (P = .0001), metastatic lymph nodes >1 (P < .0001), nodal metastases extracapsular extension (P < .0001), metastases to additional non-SNs (P = .0004), micrometastases size ≥ 0.1 mm (P = .0006), and positive LY MM-RT-PCR (P = .0007). SN tumor burden showed linear correlation with increasing Breslow thickness (P = .01). The 5-year OS rates for SLN tumor burden <0.1 mm, 1-1.0 mm, and >1.0 mm were 84%/66%/44%, respectively, and for positive and negative LY MM-RT-PCR 47%/0%, respectively. The independent factors for shorter OS (multivariate analysis): male gender, primary tumor ulceration, number of involved nodes ≥ 4, micrometastases size >1.0 mm, and, in additional model including molecular analysis-positive MM-RT-PCR results (hazard ratio [HR] 3.2), micrometastases size >1.0 mm (HR 1.13), and primary tumor ulceration (HR 2.17). Similar results were demonstrated for disease-free survival (DFS) data. CONCLUSIONS: SN tumor burden categories according to Rotterdam criteria and the positive result of LY MM-RT-PCR assay demonstrated additional, independent prognostic value in SN-positive melanoma patients, showing significant correlation with shorter DFS and OS.

Melanoma without a detectable primary site with metastases to lymph nodes.

OBJECTIVE: To compare outcomes of patients with clinical nodal melanoma metastases that occurred without a detectable primary tumor (melanoma of unknown primary site; MUP) with those with a known primary site (KPM). METHODS: We included data from 459 consecutive patients treated from 1994 to 2007 with radical therapeutic lymph node dissection (LND; stage IIIB, C) due to clinically palpable and pathologically confirmed lymph node metastases (229 axillary; 230 ilioinguinal). The median follow-up was 49 months. RESULTS: LND was performed in 59 cases (12.9%; 29 men, 30 women) due to MUP nodal metastases, including 33 axillary (14.4%) and 26 ilioinguinal (11.3%). In the MUP group, the 3- and 5-year survival rates were 48% and 41%, respectively. Similar rates were observed in patients with KPM, even with matched-pair analyses. Established prognostic factors (number of metastatic nodes, p=.005; extracapsular extension of metastases, p=.002) influenced survival in the MUP group. Relapses occurred in 31 (53%) and 299 (74.7%) cases in the MUP and KPM groups, respectively. CONCLUSIONS: Survival rates in the MUP and KPM groups were similar, and the same prognostic factors affected both. Thus, all MUP cases should be treated as standard stage III melanomas.

Emergency surgery in the era of molecular treatment of solid tumours.

In the advancing era of molecular therapy of solid tumours, emergency treatment of complications, such as bowel perforation, haemorrhage, and tumour rupture, is likely to evolve into one of the main challenges of surgical oncology. These complications might be caused by disease progression from resistance to therapy, side-effects of therapy on normal vasculature, and therapeutic induction of excessively responding tumours. This Review outlines the probability and management of emergency operations during molecularly targeted therapy of solid tumours. Special attention is given to advanced gastrointestinal stromal tumours and colorectal cancer, and therapy with imatinib, sunitinib, and bevacizumab.

Functional features of gene expression profiles differentiating gastrointestinal stromal tumours according to KIT mutations and expression.

BACKGROUND: Gastrointestinal stromal tumours (GISTs) represent a heterogeneous group of tumours of mesenchymal origin characterized by gain-of-function mutations in KIT or PDGFRA of the type III receptor tyrosine kinase family. Although mutations in either receptor are thought to drive an early oncogenic event through similar pathways, two previous studies reported the mutation-specific gene expression profiles. However, their further conclusions were rather discordant. To clarify the molecular characteristics of differentially expressed genes according to GIST receptor mutations, we combined microarray-based analysis with detailed functional annotations. METHODS: Total RNA was isolated from 29 frozen gastric GISTs and processed for hybridization on GENECHIP HG-U133 Plus 2.0 microarrays (Affymetrix). KIT and PDGFRA were analyzed by sequencing, while related mRNA levels were analyzed by quantitative RT-PCR. RESULTS: Fifteen and eleven tumours possessed mutations in KIT and PDGFRA, respectively; no mutation was found in three tumours. Gene expression analysis identified no discriminative profiles associated with clinical or pathological parameters, even though expression of hundreds of genes differentiated tumour receptor mutation and expression status. Functional features of genes differentially expressed between the two groups of GISTs suggested alterations in angiogenesis and G-protein-related and calcium signalling. CONCLUSION: Our study has identified novel molecular elements likely to be involved in receptor-dependent GIST development and allowed confirmation of previously published results. These elements may be potential therapeutic targets and novel markers of KIT mutation status.

Rectal gastrointestinal stromal tumors associated with a novel germline KIT mutation.

Somatic, activating mutations of KIT or PDGFRA are early oncogenic events in the majority of sporadic gastrointestinal stromal tumors (GISTs). Also a number of families with GISTs have been described in recent years. The familial GIST syndrome is a rare autosomal dominant disorder with high penetrance and diverse manifestations associated mostly with germline KIT mutations. In this report, we show a novel germline mutation in the juxtamembrane domain of KIT, identified in 2 brothers, both presenting with recurrent, high risk/malignant rectal GISTs. The KIT p.Q575_P577delinsH mutation was found in tumor samples as well as in peripheral blood leukocytes from both patients, proving that the mutation was indeed inherited. Besides rectal GISTs, no other features characteristic for the familial GIST syndrome was observed in either brother or any of their first-degree relatives. The patients were treated with imatinib, achieving either long-term partial response or stable disease. This observation confirms that imatinib can be successfully used in familial GISTs, as it is used in the sporadic advanced tumors, and that tumors bearing a KIT p.Q575_P577delinsH mutation are responsive to imatinib treatment.

Predictive factors for long-term effects of imatinib therapy in patients with inoperable/metastatic CD117(+) gastrointestinal stromal tumors (GISTs).

THE PURPOSE: To analyze the outcomes of treatment and factors predicting effects of imatinib (IM) therapy in inoperable/metastatic gastrointestinal stromal tumors (GIST) CD117(+) patients. MATERIALS AND METHODS: We identified 232 patients in a prospectively collected Clinical GIST Registry with advanced inoperable/metastatic GIST treated with IM 400-800 mg daily (129 males and 103 females and median age 56 years). Median follow-up time was 26 months. RESULTS: The estimated 3-year progression-free survival (PFS; calculated from the date of the start of IM) was 54% and median PFS was 40.5 months. The following factors significantly and negatively influenced PFS in univariate analysis: poor baseline World Health Organization (WHO) performance status > or = 2 (P < 0.00001), tumor genotype indicating other than KIT exon 11 isoform (P = 0.005), baseline high neutrophils count (P < 0.00001), age <45 years at the diagnosis (P = 0.04), mitotic index >10/50 high-power fields (HPF) (P = 0.001), GIST histological type other than spindle-cell (P = 0.03), baseline low albumin level (P = 0.0005), low baseline hemoglobin level (P < 0.00001), and primary overtly malignant tumors (unresectable and/or metastatic lesions at presentation) (P = 0.05). We identified four factors negatively affecting PFS, statistically significant (P < 0.05) in multivariate analysis: baseline poor WHO performance status > or = 2, high baseline neutrophils count (>5 x 10(9)/l), tumor genotype indicating the presence of non-exon 11 KIT mutant and mitotic index >10/50 HPF. CONCLUSIONS: We confirmed that many advanced GIST patients benefit from IM therapy for a prolonged time, although resistance to therapy is observed. We identified four independent biological factors influencing the PFS during long-term IM therapy.

Post-surgery adjuvant therapy with intermediate doses of interferon alfa 2b versus observation in patients with stage IIb/III melanoma (EORTC 18952): randomised controlled trial.

BACKGROUND: Individuals affected by melanoma with thick primary tumours or regional node involvement have a poor outlook, with only 30-50% alive at 5 years. High-dose and low-dose interferon alfa have been assessed for the treatment of these patients, with the former having considerable toxicity and a consistent effect on disease free survival, but not on overall survival, and the latter no consistent effect on either. Our aim was, therefore, to assess the effect of two regimens of interferon of intermediate dose versus observation alone on distant metastasis-free interval (DMFI) and overall survival in such patients. METHODS: We did a randomised controlled trial in 1388 patients who had had a thick primary tumour (thickness > or = 4 mm) resected (stage IIb) or regional lymph node metastases dissected (stage III) and had been assigned to 13-months (n=553) or 25 months (n=556) of treatment with subcutaneous interferon alfa 2b, or observation (n=279). Treatment comprised 4 weeks of 10 million units (MU) of interferon alfa (5 days per week) followed by either 10 MU three times a week for 1 year or 5 MU three times a week for 2 years, to a total dose of 1760 MU. Our primary endpoint was DMFI. Analyses were by intent to treat. FINDINGS: After a median follow-up of 4.65 years, we had recorded 760 distant metastases and 681 deaths. At 4.5 years, the 25-month interferon group showed a 7.2% increase in rate of DMFI (hazard ratio 0.83, 97.5% CI 0.66-1.03) and a 5.4% improvement in overall survival. The 13-month interferon group showed a 3.2% increase in rate of DMFI at 4.5 years (0.93, 0.75-1.16) and no extension of overall survival. Toxicity was acceptable, with 18% (195 of 1076) of patients going off study because of toxicity or as a result of refusal of treatment because of side-effects. INTERPRETATION: Interferon alfa as used in the regimens studied does not improve outcome for patients with stage IIb/III melanomas, and cannot be recommended. With respect to efficacy of the drug, duration of treatment seemed more important than dose, and should be assessed in future trials.

[Cutaneous melanoma during pregnancy--a case report]. / Czerniak skóry rozpoznany w ciazy--opis przypadku.

Cutaneous melanoma is a tumour which has the highest increase of incidence per year. In Poland, the process reaches 10%. In this essay, a case of cutaneus melanoma co-existing with pregnancy was presented. The woman was 36 years old. The neoplasm was diagnosed during the eighth week of her second pregnancy. An excision biopsy of the skin lesion on the back surface of the left shank was carried out. III degree melanoma malignum according to Clark's, and 1,6 mm according to Breslov was diagnosed. During the 35th week of pregnancy, the woman was hospitalized because of threatening premature labour. During her stay at the department, enlarged inguinal lymph nodes were observed. Because of the advanced pregnancy, the patient was qualified to limfadectonomy after labour. In the 38th week of pregnancy, she delivered by spontaneous labour a healthy baby. After two weeks, an inguinal limfadectonomy was carried out. In the histopathological analysis, metastases to lymph nodes were diagnosed. They did not cross the nodular capsules. The patient remains under monthly oncological observation. Eight months after delivery, thirteen months from the removal of the primary lesion, no lesions in the physical examination and other additional examinations have been diagnosed. The accurate evaluation of the pigmented nevus appearance could contribute to the diagnosis of the melanoma in the early stage of progression. Pregnant women, who notice a change in the look of a nevus should be directed to a dermatological consultation.

Sentinel lymph node biopsy in melanoma patients with clinically negative regional lymph nodes--one institution's experience.

The purpose of this prospective study of sentinel lymph node (SLN) biopsy in a large series of melanoma patients with clinically negative regional lymph nodes from one cancer centre was to analyse the reliability of the procedure, the pattern of failures during follow-up and the factors affecting the clinical outcome of patients. Between April 1995 and November 2001, 726 consecutive patients with primary cutaneous malignant melanoma underwent SLN biopsy with preoperative lymphoscintigraphy. The vital blue dye technique was used in 170 patients, and the blue dye technique combined with intraoperative lymphoscintigraphy in 556 patients. The primary melanoma sites were head and neck in nine patients, the extremities in 419 patients, and the trunk in 298 patients. The median Breslow thickness was 3.0 mm. All patients were followed closely, the median follow-up time being 34 months. The sentinel node(s) were successfully identified in 96% of patients. Intraoperative lymphoscintigraphy combined with the blue dye technique improved the SLN identification rate (technical success in 97.3% of cases) compared with the blue dye technique alone (technical success in 91.6%). The rate of failed SLN procedures was significantly (P = 0.007) lower in inguinal basins (3.1%) compared with axillary basins (7.9%). SLN metastases were detected in 147 patients (20.2%). The presence of SLN metastases correlated significantly with primary tumour thickness and ulceration (P < 0.001). The false-negative SLN biopsy rate was 4.66% (27 out of 579 SLN-negative patients). All but two node-positive patients underwent complete lymphadenectomy. Lymph nodes other than SLNs were found to contain metastases in 26.9% of patients (39 out of 145). The 5 year overall survival (OS) rate was 84% for SLN-negative patients and 40% for SLN-positive patients. Five variables showed a strong, statistically significant negative independent prognostic association with OS: positive SLN status (P = 0.000001), primary melanoma thickness > 4 mm (P = 0.0009), male gender (P = 0.001), more than one lymph node involvement (P = 0.02) and lymph node extracapsular extension (P = 0.03). SLN biopsy is currently a valuable and effective diagnostic procedure for the precise staging of patients with clinically N0 cutaneous melanoma. So far SLN biopsy seems to be the only accessible method for consciously oriented detection of nodal micrometastases in melanoma that would otherwise go undetected. SLN status is the most important factor proven to distinguish high and low risk melanoma patients.

[Cutaneous melanoma during pregnancy at the Cancer Center-Institute in Warsaw]. / Czerniak skóry rozpoznany podczas ciazy w materiale Centrum Onkologii--Instytutu w Warszawie.

Malignant melanoma is a neoplasm which frequency has been increasing rapidly in Poland. The paper describes five cases of patients with cutaneous melanoma coexisting with pregnancy, who have been recently treated in the Department of Soft Tissue/Bone Tumors of M. Sklodowska-Curie Memorial Cancer--Institute of Oncology, Warsaw. All patients presented clinically advanced primary lesions with poor prognosis. In paper recommendations for treatment of women with suspicious cutaneous lesions before or during pregnancy and patients with melanoma planning a pregnancy are presented. The suspicion of melanoma is indication for immediate excisional biopsy by local anesthesia. Further treatment should be performed in tertiary oncological centres. There is no evident clinical data that pregnancy has a significant impact on progression of melanoma. The most important factor influencing prognosis of melanoma is the stage of the disease at the diagnosis. There are no grounds for abortion in pregnant women with melanoma in I/II/III stages.

Cutaneous melanoma with nodal metastases in elderly people.

BACKGROUND: The impact of age on melanoma patient outcomes is uncertain. OBJECTIVE: The aim of the study was to analyze the characteristics and treatment outcomes in cutaneous melanoma patients ≥ 65 years of age with lymph node metastases. METHODS: We analyzed data from 849 consecutive patients with stage III cutaneous melanoma who were treated between 1994 and 2007 at one institution. Of these, 225 (26.5%) were ≥ 65 years of age. The characteristics and disease-specific survival (DSS) from lymph node dissection (LND) date of patients ≥ 65 years of age were compared with those of younger patients. Median follow-up time was 49 months (range: 6-140 months). RESULTS: In the ≥ 65 years group (51.6% men), the median Breslow thickness was 5.0 mm and 70% was ulcerated. The 5-year DSS rate was significantly lower in older patients (34%). Multivariate analysis identified older age as an independent prognostic factor for DSS in the overall group. Independent negative prognostic factors of DSS in the group of older stage III patients were identified as features of nodal metastases (extracapsular invasion, HR = 1.74, P = 0.009; and ≥ 4 involved lymph nodes, HR = 1.5; P = 0.008) and male sex (HR = 1.5; P = 0.039). CONCLUSIONS: This analysis showed that melanoma patients ≥ 65 years of age are characterized by a higher primary tumor stage and worse prognosis in the presence of regional node metastases than younger patients. Additionally, the results indicate that the same radical surgical therapy is necessary for patients ≥ 65 years old as in younger patients.

The megavoltage radiation therapy in treatment of patients with advanced or difficult giant cell tumors of bone.

PURPOSE: To assess the outcomes of radiotherapy, in terms of local control and treatment complications, of advanced or difficult giant cell tumors of bone (GCTB) that could not be treated by surgery. METHODS AND MATERIALS: Among 122 consecutive patients with confirmed GCTB from 1985 to 2007, 77 patients were treated by megavoltage radiotherapy because they were inappropriate candidates for surgery. We have performed analysis of all data in terms of progression-free survival (PFS) and treatment morbidity. Median follow-up time was 58 months. RESULTS: In the irradiated group, maximal tumor size ranged from 5 to 18 cm (median, 8.5). Anatomic distribution was as follows: femur, 27 cases; tibia, 19; radial/ulnar bone, 12; sacrum, 9; pelvic bones, 5; other, 5. Twenty-one patients (27%) were referred for local recurrence after ≥1 other treatment procedures. The radiation doses ranged from 26 to 89 Gy (median, 56; administered 1.8-2.0 Gy/fraction with average total duration of treatment of 5-7 weeks); 8 patients (10%) received <50 Gy. All patients tolerated treatment well without acute or late complications. All patients except two are alive. Local control was achieved in 65 patients (84%; bone recalcification/restitution of joint functions), 12 patients showed signs of local progression, all within irradiated fields (9 were treated successfully with salvage surgery). Five- and 10-year local PFS were 83% and 73%, respectively. Three patients developed lungs metastases. Malignant transformation of GCTB occurred in two patients. CONCLUSIONS: GCTB can be safely and effectively treated with megavoltage radiotherapy with local control rate >80% at 5 years. Our study confirms that radiotherapy of GCTB offers an alternative to difficult or complex surgery and may be an option of choice in the treatment of inoperable patients.

Surgery combined with brachytherapy in patients with retroperitoneal sarcomas.

PURPOSE: The primary aim of this work was to analyze feasibility of combined treatment of retroperitoneal sarcomas (RS): surgery (S) and intraoperative brachytherapy (IOBRT). The secondary aim was to analyze results and complications after this treatment. MATERIAL AND METHODS: 84 patients with retroperitoneal sarcomas were qualified for combined treatment (S and IOBRT) between June 1998 and September 2006. 65 of the patients (77.4%) had local recurrences. Sarcomas with intermediate and high grade of histological malignancy (G2, G3 - 76.2%) were the most frequent within the all surgically treated patients. Resection ability (R0/R1) in analyzed group of patients was estimated as 85% (74 cases). After intraoperative evaluation, 57 (67.8%) patients were qualified for IOBRT. Since 2000, in 34 patients (60%) an adjuvant postoperative external beam radiation therapy (EBRT) in dose of 50 Gy was applied. Median follow-up of the surviving patients was 40 months. RESULTS: On the basis of the univariate analysis, relevant aspects negatively influencing overall survival rate within the RS group treated with IOBRT were as follows: surgery of sarcoma recurrence (p = 0.002), higher grade of histological malignancy (p = 0.05), histological type different than liposarcoma (p = 0.05) as well as no adjuvant EBRT (p = 0.05). On the basis of multivariate analysis one can ascertain that relevant factors negatively influencing LRFS in RS patients treated with IOBRT were: surgery due to recurrence of sarcoma (p = 0.008) and lack of EBRT (p = 0.01). CONCLUSIONS: Combined treatment (surgery and brachytherapy) was possible to be carried out on 68% of RS patients. The overall number of complications was quite high, however acceptable, taking into consideration the application of extensive, multi-organ treatments in case of sarcoma recurrences in this localization. The results suggest that the method of treatment will improve the final outcome when most of patients will be qualified for treatment of primary sarcomas in experienced centre.

Imatinib mesylate in advanced dermatofibrosarcoma protuberans: pooled analysis of two phase II clinical trials.

PURPOSE: Dermatofibrosarcoma protuberans (DFSP) is a dermal sarcoma typically carrying a translocation between chromosomes 17 and 22 that generates functional platelet-derived growth factor B (PDGFB). PATIENTS AND METHODS: Two distinct phase II trials of imatinib (400 to 800 mg daily) in patients with locally advanced or metastatic DFSP were conducted and closed prematurely, one in Europe (European Organisation for Research and Treatment of Cancer [EORTC]) with 14-week progression-free rate as the primary end point and the other in North America (Southwest Oncology Group [SWOG]) with confirmed objective response rate as the primary end point. In the EORTC trial, confirmation of PDGFB rearrangement was required, and surgery was undertaken after 14 weeks if feasible. The SWOG study confirmed t(17;22) after enrollment. RESULTS: Sixteen and eight patients were enrolled onto the EORTC and SWOG trials, respectively. Tumor size ranged from 1.2 to 49 cm. DFSP was located on head/neck, trunk, and limb in seven, 11, and six patients, respectively, and was classic, pigmented, and fibrosarcomatous DFSP in 13, one, and nine patients, respectively. Metastases were present in seven patients (lung involvement was present six patients). Eleven patients (4%) had partial response as best response, and four patients had progressive disease as best response. Median time to progression (TTP) was 1.7 years. Imatinib was stopped in 11 patients because of progression, one patient because of toxicity, and two patients after complete resection of disease. Median overall survival (OS) time has not been reached; 1-year OS rate was 87.5%. CONCLUSION: Imatinib is active in DFSP harboring t(17;22) including fibrosarcomatous DFSP, with objective response rate approaching 50%. Response rates and TTP did not differ between patients taking 400 mg daily versus 400 mg twice a day.

Gastrointestinal stromal tumors: key to diagnosis and choice of therapy.

The common feature of gastrointestinal stromal tumors (GISTs) is the expression of KIT protein or acquisition of activating, constitutive mutations in the KIT or platelet-derived growth factor receptor alpha (PDGFRA) genes that are the early oncogenic events during GIST development. With these discoveries, GIST has emerged as a distinct sarcoma entity, enabling the introduction of targeted therapy using the inhibition of KIT/PDGFRA and their downstream signaling cascade. The introduction of a small-molecule tyrosine kinase inhibitor, imatinib mesylate, to clinical practice has revolutionized the treatment of patients with advanced GISTs and is currently approved as first-line treatment for patients with metastatic and/or inoperable GISTs. Mutation screening is currently a tool in GIST diagnosis, assessment of sensitivity to tyrosine kinase inhibitors, and prediction of achieving response to molecularly targeted therapy. This article discusses the histologic and molecular criteria for distinguishing GISTs from other types of sarcoma, and the molecular diagnostic tools that are currently available or in development to assist in therapy decisions.

Molecular staging by multimarker reverse transcriptase-polymerase chain reaction assay of lymphatic drainage and blood from melanoma patients after lymph node dissection.

Reverse transcriptase-polymerase chain reaction (RT-PCR)-mediated detection of melanoma cells may be a prognostic factor for disease outcome. We investigated the presence of melanoma cells in lymphatic drainage and blood in melanoma patients after lymph node dissection (LND) via the highly sensitive multimarker (MM) RT-PCR assay. We collected 24-h lymph fluid (LY) and peripheral blood (BL) from 107 stage III melanoma patients after radical LND (59 axillary and 48 ilioinguinal LND). Tyrosinase, MART1 and uMAGE mRNA levels were determined by RT-PCR to detect melanoma cells, and the presence of at least one marker signified a positive result. All patients underwent follow-up (median for survivors, 21 months, range: 4-37 months). Forty patients (37.4%) were positive for LY MM RT-PCR and 28 (26.2%) were positive based on BL MM RT-PCR. No differences for disease-free survival (DFS) curves according to BL MM RT-PCR were observed, but we found significant differences in the estimated 24-month DFS rate for patients with at least one marker and those without any marker in lymph fluid [18.9% (95% confidence interval: 1.4-37.5%) and 42.1% (95% confidence interval: 29.7-54.5%), median: 9.9 and 15.3 months, respectively] (P=0.04). Detection of multiple markers in lymph fluid correlated with shorter DFS. Approximately 37% of lymph fluid after radical LND were positive by MM RT-PCR, which correlated significantly with early melanoma recurrences and shorter survival. The LY MM RT-PCR seems to be an effective prognostic tool for stage III melanoma patients. The MM RT-PCR analysis of single peripheral blood sample in these patients did not have additional prognostic value.

Risk criteria and prognostic factors for predicting recurrences after resection of primary gastrointestinal stromal tumor.

BACKGROUND: The introduction of adjuvant imatinib in gastrointestinal stromal tumors (GISTs) raised debate over the accuracy of National Institutes of Health risk criteria and the significance of other prognostic factors in GIST. METHODS: Tumor aggressiveness and other clinicopathological factors influencing disease-free survival (DFS) were assessed in 335 patients with primary resectable CD117-immunopositive GISTs (median follow-up, 31 months after primary tumor resection) from a prospectively collected tumor registry. RESULTS: Overall median DFS was 37 months, and estimated 5-year DFS was 37.8 %. In univariate analysis, high or intermediate risk group (P < .000001), mitotic index >5/50 high-power field (P < .00001), primary tumor size >5 cm (P < .00001), nongastric primary location (P = .0001), male sex (P = .01), R1 resection/tumor rupture (P = .0003), and epithelioid cell or mixed cell pathological subtype (P = .05) negatively affected DFS. In multivariate analysis, statistically significant factors negatively influencing DFS for model 1 were mitotic index >5/50 high-power field (P = .004), primary tumor size >5 cm (P = .001), male sex (P = .003), R1 resection/tumor rupture (P = .04), and nongastric primary tumor location (P = .02), and for model 2 were high/intermediate risk primary tumor (P < .0001 and P = .008, respectively), male sex (P = .007), resection R1/tumor rupture (P = .01), and nongastric primary tumor location (P = .02). Five-year DFS for high, intermediate, and low/very low risk group was 20%, 54%, and 96%, respectively. CONCLUSIONS: The risk criteria for assessing the natural course of primary GISTs were validated, but additional independent prognostic factors-primary tumor location and sex--were also identified.

Different factors are responsible for predicting relapses after primary tumors resection and for imatinib treatment outcomes in gastrointestinal stromal tumors.

BACKGROUND: The development of accurate diagnostic methods in gastrointestinal stromal tumors (GISTs) and the introduction of imatinib (IM) therapy has focused attention on the factors influencing the prognosis of patients with primary lesions as well as of patients with advanced disease treated with imatinib. MATERIAL/METHODS: The clinico-pathological and genetic factors influencing disease-free survival (DFS) in 335 patients with primary CD117-immunopositive tumors (group A; calculated from primary tumor resection) and progression-free survival (PFS) in 232 metastatic/unresectable GIST patients treated with IM (group B; calculated from the start of imatinib therapy) were analyzed. RESULTS: In group A, statistically significant factors negatively influencing DFS(five-year DFS: 38%), both in univariate and multivariate analysis, were: primary tumor size >5 cm, mitotic index >5/50 HPF (high-power fields), male gender, primary tumor R1 resection or tumor rupture, non-gastric primary tumor localization. In group B, five factors negatively affecting PFS (three-year PFS: 54%) were identified, which were statistically significant both in univariate and multivariate analyses: WHO performance status >/=2, tumor genotype indicating other than exon 11 KIT mutation, high baseline pre-IM granulocyte count, mitotic index >10/50 HPF, and age <45 years at diagnosis. CONCLUSIONS: Different sets of independent biological and pathological prognostic factors were identified for the assessment of the natural course of primary GIST and for the prediction of PFS during IM therapy for advanced GIST.

Presence of homozygous KIT exon 11 mutations is strongly associated with malignant clinical behavior in gastrointestinal stromal tumors.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of gastrointestinal tract. GISTs range from benign indolent neoplasms to highly malignant sarcomas. Gain-of-function mutations of tyrosine kinase receptors, KIT or PDGFRA, have been identified in most GISTs. In this study, we report 36 GIST patients whose tumors had homozygous KIT exon 11 mutations detected by direct sequencing of PCR products. Loss of heterozygosity in KIT locus and other chromosome 4 loci were documented in majority of these tumors. However, fluorescence in situ hybridization with KIT locus-specific probe and chromosome 4 centromeric enumeration probe showed no evidence of KIT hemizygosity in a majority of analyzed cases. These findings are consistent with duplication of chromosome 4 with KIT mutant allele. Homozygous KIT exon 11 mutations were found in 33 primary tumors and 7 metastatic lesions. In two cases, shift from heterozygosity to homozygosity was documented during tumor progression being present in metastases, but not in primary tumors. Among primary GISTs, there were 16 gastric, 18 intestinal and 2 from unknown locations. An average primary tumor size was 12 cm and average mitotic activity 32/50 HPFs. Out of 32 tumors 29 (90.6%) with complete clinicopathologic data were diagnosed as sarcomas with more than 50% risk of metastatic disease, and 26 of 29 patients with follow-up had metastases or died of disease. An average survival time among pre-imatinib patients, who died of the disease was 33.4 months. Based on these findings, we conclude that presence of homozygous KIT exon 11 mutations is associated with malignant course of disease and should be considered an adverse prognostic marker in GISTs.

Survival analysis and clinicopathological factors associated with false-negative sentinel lymph node biopsy findings in patients with cutaneous melanoma.

BACKGROUND: We analyzed the outcomes and factors associated with false-negative (FN) results of sentinel lymph node (SLN) biopsy findings in patients with cutaneous melanoma. SLN biopsy failure rate was defined as nodal recurrence in the biopsied regional basin without previous local or in-transit recurrence. METHODS: Between April 1997 and December 2004, a total of 1207 patients with cutaneous melanoma with a median Breslow thickness of 2.4 mm underwent SLN biopsy by preoperative and intraoperative lymphoscintigraphy combined with dye injection. In 228 cases, we found positive SLNs; of these, 220 underwent completion lymph node dissection (CLND). Median follow-up was 3 years. RESULTS: The SLN biopsy failure rate was 5.8% (57 of 979 SLN negative). Median time to occurrence of FN relapse after SLN biopsy was 16 months (range, 3-74 months). The FN SLN biopsy results correlated with primary tumor thickness >4 mm (P = .0012), primary tumor ulceration (P = .0002), primary tumor level of invasion Clark stage IV/V (P = .0005), and nodular melanoma histological type (P = .0375). Five-year overall survival, calculated from the date of primary tumor excision, in the FN group was 53.7%, which was not statistically significantly worse than the CLND group (56.8%; P = .9). The FN group was characterized by a higher ratio of two or more metastatic nodes and extracapsular involvement of lymph nodes after LND compared with the CLND group (P < .0001 and P < .0001, respectively). Additional detailed pathological review of FN SLN revealed metastatic disease in 14 patients, which decreased the SLN biopsy failure rate to 4.4% (43 of 979). CONCLUSIONS: Survival of patients with FN results of SLN biopsy does not differ statistically significantly from that of patients undergoing CLND, although it is slightly lower. The SLN biopsy failure rate is approximately 5.0% in long-term follow-up and is associated mainly with the same factors that indicate a poor prognosis in primary melanoma.