Impact of [18F]fluorodeoxyglucose positron emission tomography on surgical management of melanoma patients

Diagnostic Performance of [18F]F-FDG Positron Emission Tomography (PET) in Non-Ophthalmic Malignant Melanoma: A Systematic Review and Meta-Analysis of More Than 10,000 Melanoma Patients

We described the diagnostic performance of [18F]F-FDG-PET in malignant melanoma by conducting a comprehensive systematic review and meta-analysis of the existing literature. The study was designed following PRISMA-DTA. Original articles with adequate crude data for meta-analytic calculations that evaluated [18F]F-FDG-PET and compared it with a valid reference standard were considered eligible. The pooled measurements were calculated based on the data level (patient/lesion-based). Regarding sub-groups, diagnostic performances were calculated for local, regional and distant involvement. The bivariate model was employed to calculate sensitivity and specificity. The initial search resulted in 6678 studies. Finally, 100 entered the meta-analysis, containing 82 patient-based (10,403 patients) and 32 lesion-based (6188 lesions) datasets. At patient level, overall, [18F]F-FDG-PET had pooled sensitivity and specificity of 81% (95%CI: 73-87%) and 92% (95%CI: 90-94%), respectively. To detect regional lymph node metastasis, the pooled sensitivity and specificity were 56% (95%CI: 40-72%) and 97% (95%CI: 94-99%), respectively. To detect distant metastasis, they were 88% (95%CI: 81-93%) and 94% (95%CI: 91-96%), respectively. At lesion level, [18F]F-FDG-PET had a pooled sensitivity and specificity of 70% (95%CI: 57-80%) and 94% (95%CI: 88-97%), respectively. Thus, [18F]F-FDG-PET is a valuable diagnostic modality for melanoma assessment. It was accurate in various clinical scenarios. However, despite its high specificity, it showed low sensitivity in detecting regional lymph node metastasis and could not replace lymph node biopsy.

Application of CO2 laser evaporation in locally advanced melanoma

Aim

This study aims to investigate the role of CO₂ laser evaporation in the treatment of melanoma patients with satellite or in-transit metastases.

Materials & methods

Patients who underwent CO₂ laser evaporation were retrospectively included between November 2002 and August 2018. The Sharplan 40C CO₂ laser was used with a high pulse wave mode. Data concerning patient and tumor characteristics, CO₂ laser evaporation and subsequent therapies were collected.

Results

A total of 26 patients were included. Median duration of local control was 5.5 months. The median number of lesions evaporated per treatment was three (1-16); patients received a median of three (1-19) treatments.

Conclusion

In a selected group of melanoma patients with satellite or in-transit metastases, CO₂ laser evaporation should be considered as treatment for local control.

Can 18F-FDG PET/CT predict recurrence in patients with cutaneous malignant melanoma?

The aim of this study was to evaluate the prognostic significance of maximum standardized uptake value (SUVmax) of primary cutaneous malignant melanoma (CMM) lesions by 18F-FDG positron emission tomography/ computerized tomography (PET/ CT) in terms of recurrence. Patients, methods: 37 CMM patients (17 men, mean age: 61.7 ± 13.6 years) that underwent PET/CT at presentation were enrolled in this study. Recurrence was determined by histological confirmation or by radiological and clinical follow- up for at least 8 months after curative surgery. Clinical variables such as age, sex, clinical stage, and primary lesion location, thickness, and ulceration, and SUVmax values were analyzed with respect to their usefulness for predicting recurrence. Results: SUVmax was found to be significantly higher in patients with ulceration of primary lesion of CMM (p = 0.004) and in patients with a stage ≥ III (p < 0.000). Patients that experience recurrence had a significantly higher mean SUVmax value (4.9 ± 2.9) than patients who did not (2.1 ± 1.5, p = 0.024). ROC analysis showed that a SUVmax cut-off value 2.2 had high sensitivity (88.9%) and specificity (67.9%) for predicting recurrence. Kaplan-Meier analysis identified ulceration of primary lesion (p = 0.034), stage ≥ III (p = 0.019) and SUVmax ≥ 2.2 (p = 0.002) as predictors of recurrence. However, Cox proportional-hazards analysis showed that only SUVmax (p = 0.025, relative risk 11.063) significantly predicted recurrence. Conclusion: Preoperative SUVmax of primary lesion was found to be the most potent predictor of recurrence in CMM patient. Patients with high SUV max of primary lesion should be followed meticulously for recurrence.

Whole body PET/CT in the follow-up of asymptomatic patients with stage IIB-IIIB cutaneous melanoma. Acta Oncol 2016;55:1355-1359. [PMID: 27553064 DOI: 10.1080/0284186x.2016.1213879]

BACKGROUND

Whole body positron emission tomography (PET)/computed tomography (CT) is a sensitive imaging technique in patients with metastatic melanoma, but its role in the follow-up of asymptomatic high-risk patients is unclear. The aim was to study the role of PET/CT as a routine surveillance imaging tool in asymptomatic high-risk patients at the early stage of follow-up combined with a sufficient follow-up over several years.

MATERIAL AND METHODS

A total of 110 asymptomatic patients with clinically local American Joint Committee on Cancer (AJCC) stage IIB-IIIB melanoma underwent routine whole body PET/CT scanning after a mean interval of seven months after initial surgery. Clinical data were retrospectively analyzed after a median follow-up time of 4.6 years.

RESULTS

Recurrent melanoma was detected in 45 patients (41%) and 36 (33%) died of melanoma. In 11 asymptomatic patients (10%) occult disease was detected with a single PET/CT. In seven of these patients (64%), positive PET/CT finding had major influence in treatment decisions. Four patients underwent surgical metastasectomy and two of them remained disease-free. In 34 patients (31%) PET/CT revealed no disease, but recurrence was detected at a median time of 19 months after negative PET/CT scan. In 50 patients (45%) PET/CT finding was true negative. In 15 patients (14%) scan was false positive leading to additional management or repetitive imagings.

CONCLUSION

A single PET/CT could detect 24% of all recurrences in asymptomatic melanoma patients at the early stage of follow-up, but an earlier detection of occult metastases did not improve survival.

18F-FDG-PET/CT in the Staging and Management of Melanoma: A Prospective Multicenter Ontario PET Registry Study

PURPOSE

The Ontario PET Registry was established to provide evidence on the clinical impact of 18-FDG-PET/CT (PET) imaging to inform Ontario Health Insurance Plan funding decisions. The melanoma registry assessed the use of melanoma staging by PET in advanced or high-risk melanoma as a useful adjunct to clinical and standard radiologic investigation.

MATERIALS AND METHODS

Between January 2011 and July 2013, approximately 319 consecutive patients with potentially resectable localized high-risk melanoma or recurrent disease under consideration for metastasectomy underwent PET imaging for staging across 9 institutions in Ontario. Pre-PET stage information was provided by the referring clinician and compared with post-PET stage. The ability of PET to reclassify disease from M0 to M1 status was assessed. The registry data were then linked to provincial administrative databases using deidentified health insurance numbers to determine PET stage-based rates of systemic therapy, radiotherapy, and surgery.

RESULTS

There was a significant increase in stage to M1 status after PET in 56 of 319 patients (17.6%) (P < 0.0001). There was no significant relationship between upstaging with PET and the proportion of patients receiving radiation therapy (P = 0.066) or systemic therapy (P = 0.072). There was a significant relationship between upstaging with PET and the proportion of patients undergoing surgical resection of metastases distant to the primary melanoma site (P = 0.034).

CONCLUSIONS

This prospective, multicenter registry of high-risk or advanced melanoma found that PET significantly upstages patients and impacts surgical management.

The preoperative SUVmax for (18)F-FDG uptake predicts survival in patients with colorectal cancer

Background

The study was to investigate whether ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake, analyzed by positron emission tomography (PET), can be used preoperatively to predict survival in Chinese patients with colorectal carcinoma.

Methods

A prospectively maintained colorectal cancer database was retrospectively reviewed between June 2009 and December 2011. All included patients had been newly diagnosed with colorectal cancer (of various stages) and evaluated by ¹⁸F-FDG-PET/computed tomography (CT) within the 2 weeks preceding surgery. Univariate and multivariate analyses were used to determine whether the maximal standardized uptake value (SUVmax) and various clinicopathological and immunohistochemical factors were correlated with survival. Receiver operating characteristics (ROC) curve and Kaplan-Meier survival curve analyses were used to explore whether SUVmax could predict survival in these patients.

Results

A total of 107 patients were enrolled in the study (mean age, 59.26 ± 12.66 years; 66.35 % males), with 77 surviving to the end of follow-up (average 60 months). Univariate analysis indicated that tumor size, TNM stage, nodal metastasis, the ratio of metastasized nodes to retrieved nodes, cyclin D1 immunostaining and SUVmax correlated with survival (P < 0.05). Multivariate analysis showed that only TNM stage and SUVmax were associated with survival (P < 0.05). ROC curve analysis determined the optimal SUVmax cutoff for predicting survival to be 11.85 (sensitivity, 73.3 %; specificity, 75.3 %). Survival was significantly longer in patients with preoperative SUVmax ≤11.85 (P < 0.001, log-rank test).

Conclusions

SUVmax, measured by ¹⁸F-FDG-PET/CT, provides a useful preoperative prognostic factor for patients with colorectal cancer.

Patients undergoing lymphadenectomy for stage III melanomas of known or unknown primary site do not differ in outcome

The outcome of patients with palpable melanoma metastases in lymph nodes in the presence (metastatic melanoma of known primary site, MKP) or absence (metastatic melanoma of unknown primary site, MUP) of an identifiable primary tumour remains controversial. Some of the previous studies contained large case series that included historical patients. We aimed to compare outcomes of those with MUPs versus MKPs with palpable lymph node invasion, after staging with modern imaging technology. Aprospective study of patients from a single tertiary institution who were undergoing lymph node dissection for palpable metastatic melanoma between 2000 and 2011 was conducted. All patients were ascertained by computerised tomography scanning and most diagnosed after 2004 had positron emission tomography scanning also. Clinicopathological details about the primary melanoma and lymph node dissections were gathered. Factors associated with recurrence and melanoma-specific mortality in those with MKP and with MUP were assessed using univariate and multivariate analyses. Out of 485 patients studied, 82 had MUP and 403 had MKP. Patients were followed up for a median of 17.4 and 19.0 months, for MKP and MUP, respectively. Five-year adjusted melanoma-specific survival was 58% for MUPs versus 49% for MKPs and was not significantly different between the two groups (adjusted Cox proportional Hazard ratio = 0.88 95% confidence interval [0.58, 1.33] p = 0.54). Previously established prognostic factors such as number of positive nodes and extracapsular extension were confirmed in both sets of patients. We conclude that among melanoma patients presenting with clinically detectable nodes, when accurately staged, those without an identifiable primary lesion have similar outcomes to patients with MKP.

Outcome of clinical stage III melanoma patients with FDG-PET and whole-body CT added to the diagnostic workup

BACKGROUND

Combined whole-body FDG-PET and CT provide the most comprehensive staging of melanoma patients with palpable lymph node metastases (LNM). The aim of this study is to analyze survival of FDG-PET and CT negative or positive melanoma patients and to assess which factors have independent prognostic impact on survival of these patients.

METHODS

Patients with palpable and histologically or cytologically proven LNM of melanoma, referred to participating hospitals for examination with FDG-PET and CT, were selected from a previous study. Melanoma-specific survival (MSS) and disease-free period (DFP) were analyzed for FDG-PET and CT positive and negative patients using the Kaplan-Meier method. Cox-regression analysis was performed to analyze which patient or melanoma characteristics had significant impact on MSS or DFP.

RESULTS

For all 252 patients 5-year MSS was 38.2%. For FDG-PET and CT negative and positive patients 5-year MSS was 47.6 and 16.9%, respectively. Disease-free period for FDG-PET and CT negative patients was 46.0% after 5 years. Gender, a positive FDG-PET and CT, LNM in axilla compared to head or neck, and presence of extranodal growth were independent factors for worse MSS in all patients. Positive FDG-PET and CT was the most important prognostic factor for MSS with a hazard ratio of 2.54 (95% CI, 1.55-4.17, P<0.001).

CONCLUSIONS

Staging melanoma patients with palpable LNM is more accurate when whole-body FDG-PET and CT is added to the diagnostic workup. Hence, FDG-PET and CT, preferably combined, are indicated in the staging of clinical stage III melanoma patients.

F-18 fluorodeoxyglucose PET/CT and post hoc PET/MRI in a case of primary meningeal melanomatosis

Primary meningeal melanomatosis is a rare, aggressive variant of primary malignant melanoma of the central nervous system, which arises from melanocytes within the leptomeninges and carries a poor prognosis. We report a case of primary meningeal melanomatosis in a 17-year-old man, which was diagnosed with (18)F-fluorodeoxyglucose (F-18 FDG) PET/CT, and post hoc F-18 FDG PET/MRI fusion images. Whole-body F-18 FDG PET/CT was helpful in ruling out the extracranial origin of melanoma lesions, and in assessing the therapeutic response. Post hoc PET/MRI fusion images facilitated the correlation between PET and MRI images and demonstrated the hypermetabolic lesions more accurately than the unenhanced PET/CT images. Whole body F-18 FDG PET/CT and post hoc PET/MRI images might help clinicians determine the best therapeutic strategy for patients with primary meningeal melanomatosis.

Role of imaging methods in metastatic melanoma

Melanoma is a malignant neoplasm of the skin deriving from melanocytes. Accounting for less than 5% of all skin cancers, melanoma is associated with approximately 75% of skin cancer-related mortality. Early detection of melanoma with surgical resection remains one of the critical factors determining favorable clinical outcomes for melanoma. Up to now, many imaging methods, such as ultrasound, computed tomography (CT), magnetic resonance imaging, and positron emission tomography/CT, have been used in the diagnosis of melanoma and metastases. This article reviews the application of imaging methods in metastatic melanoma.

Melanoma of unknown primary as a cause of intestinal obstruction - a case description

Melanoma of unknown primary applies to 1-8% of all diagnosed melanomas, whereas primary melanoma of the small intestine is a extremely rare case. One of the melanoma characteristics is its capability of forming metastases in the small intestine which very often are diagnosed during autopsy.We present a case report of diagnosed melanoma of unknown primary, whose first symptom was intestinal obstruction. Before admission to the hospital cause of intestinal obstruction, the patient didn't present any signs and symptoms. All typical localizations of primary melanoma were excluded during diagnostic procedure. Palliative right hemicolectomy and segmental small intestine resection were performed. There were no complications in the postoperative course. On the ninth day the patient was discharged from hospital.Quick identification and radical resection of melanoma metastases in the alimentary tract may improve the survival rate in this group of patients. Resection, even if it is palliative by assumption, is not only the best method of elimination of persistent symptoms but it also gives hope for longer survival.

VEGF-SPECT with ¹¹¹In-bevacizumab in stage III/IV melanoma patients

PURPOSE

A feasibility study was performed to investigate the presence of VEGF in melanoma lesions by VEGF-SPECT with (111)In-bevacizumab. In addition the effect of a single therapeutic bevacizumab dose on (111)In-bevacizumab uptake was compared with VEGF levels in resected melanoma lesions.

PATIENTS AND METHODS

Eligible were patients with stage III/IV melanoma who presented with nodal recurrent disease. VEGF-SPECT was performed after administration of 100 Mbq (111)In-bevacizumab (8 mg) at days 0, 2, 4 and 7 post injection. Tumour visualisation and quantification were compared with CT and FDG-PET. On day 7 a single dose of 7.5mg/kg bevacizumab was administered intravenously. On day 21, a second tracer dose (111)In-bevacizumab was administered and scans were obtained on days 21, 25 and 28. Metastases were surgically resected within 2 weeks after the last VEGF-SPECT scan and immunohistological (IHC) VEGF tumour expression was compared with (111)In-bevacizumab tumour uptake.

RESULTS

Nine patients were included. FDG-PET and CT detected both in total 12 nodal lesions which were all visualised by VEGF-SPECT. At baseline, (111)In-bevacizumab tumour uptake varied 3-fold between and 1.6 ± 0.1-fold within patients. After a therapeutic dose of bevacizumab there was a 21 ± 4% reduction in (111)In-bevacizumab uptake. The (111)In-bevacizumab tumour uptake in the second series positively correlated with the VEGF-A expression in the resected tumour lesions.

CONCLUSION

VEGF-SPECT could visualise all known melanoma lesions. A single dose of bevacizumab slightly lowered (111)In-bevacizumab uptake. Future studies should elucidate the role of VEGF-SPECT in the selection of patients and the individual dosing of bevacizumab treatment.

Clinical and therapeutic impact of 18F-FDG PET/CT whole-body acquisition including lower limbs in patients with malignant melanoma

OBJECTIVES

To assess the added benefit of scanning lower limbs in addition to the usual whole-body positron emission tomography/computed tomography (PET/CT) scan in patients with no known or suspected primary or metastatic melanoma involving the lower limbs.

MATERIALS AND METHODS

This is a retrospective study of 122 consecutive patients [174 2-[¹⁸F]-fluoro-2-deoxy-D-glucose (FDG) PET/CT] who underwent FDG PET/CT for staging of melanoma at different time points in the course of the disease from October 2005 to February 2009 at the Brest University Hospital. Reports of whole-body PET/CT scans including lower limbs were reviewed. PET/CT abnormalities on the lower extremities were tabulated by location and correlated with pathology, other imaging studies and at least a 6-month clinical follow-up. The usefulness of lower limbs acquisition in clinical management was evaluated according to imagery findings.

RESULTS

Among the 174 consecutive PET/CT scans performed in 122 patients, 33 scans in 28 patients highlighted abnormal FDG uptakes considered as equivocal or suggestive of malignancy in the lower limbs. In 28 cases, uptakes were located at once in the lower limbs and in the rest of the body (lung, liver, mediastinal and sub-diaphragmatic lymph nodes, adrenal glands, bone) corresponding to disseminated disease. In five cases, PET/CT uptakes were located only in lower limbs; each pathological uptake corresponded to benign lesions. Lower limbs findings never impacted clinical and therapeutic decision.

CONCLUSION

Lower limbs additional PET/CT acquisition seems to offer poor additional benefit with none unexpected lesion detected and routine skull base to upper thigh images might be sufficient for this subset of patients.

Melanoma

This chapter discusses the value of FDG-PET and combined FDG-PET/CT in staging and follow-up of melanoma patients. For melanoma patients, the presence or absence of regional lymph node metastases is one of the most important prognostic factors; the recent development of sentinel lymph node biopsy offers a highly sensitive staging method. FDG-PET has shown a limited sensitivity to detect microscopic lymph node metastases in this selected group of patients with stages I and II melanoma. However, for the detection of distant metastases, FDG-PET is frequently used. Although there is no consensus, some surgeons pursue surgical excision of metastatic disease if only one or a few sites of disease are apparent. Precise identification of the location and number of metastatic lesions could therefore be important for surgical planning. Even though patients with metastatic melanoma generally have a poor prognosis (5-year survival 3-16%), there is still a need for accurate staging. Firstly, to identify those patients who may benefit from a surgical procedure, while avoiding these potentially harmful surgical procedures for patients with multiple distant metastases. Secondly, accurate staging is important to improve the efficiency of clinical trials, and thirdly, to provide patients with detailed information about their prognosis. Taking the published literature together, and reasoning that FDG-PET/CT is the current standard in PET imaging, there may be a case for the combined PET/CT in the setting of metastatic melanoma. However, further research is needed as the benefit of the combined FDG-PET/CT vs. FDG-PET alone seems to be less than reported for other tumor entities, which may be due to the high avidity of melanoma for FDG, so that many of the metastases are detected with FDG-PET and the additional CT does not increase the sensitivity.

18F-FDG PET/CT imaging in oncology

Accurate diagnosis and staging are essential for the optimal management of cancer patients. Positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography (18F-FDG PET/CT) has emerged as a powerful imaging tool for the detection of various cancers. The combined acquisition of PET and CT has synergistic advantages over PET or CT alone and minimizes their individual limitations. It is a valuable tool for staging and restaging of some tumors and has an important role in the detection of recurrence in asymptomatic patients with rising tumor marker levels and patients with negative or equivocal findings on conventional imaging techniques. It also allows for monitoring response to therapy and permitting timely modification of therapeutic regimens. In about 27% of the patients, the course of management is changed. This review provides guidance for oncologists/radiotherapists and clinical and surgical specialists on the use of 18F-FDG PET/CT in oncology.

Contemporary diagnostic imaging modalities for the staging and surveillance of melanoma patients: a meta-analysis

BACKGROUND

Meta-analyses were performed to examine the utility of ultrasonography, computed tomography (CT), positron emission tomography (PET), and a combination of both (PET-CT) for the staging and surveillance of melanoma patients.

METHOD

Patient-level data from 74 studies containing 10,528 patients (between January 1, 1990, and June, 30, 2009) were used to derive characteristics of the diagnostic tests used. Meta-analyses were conducted by use of Bayesian bivariate binomial models to estimate sensitivity and specificity. Diagnostic odds ratios [ie, true-positive results/false-negative results)/(false-positive results/true-negative results)] and their 95% credible intervals (CrIs) and positive predictive values were used as indicators of test performance.

RESULTS

Among the four imaging methods examined for the staging of regional lymph nodes, ultrasonography had the highest sensitivity (60%, 95% CrI = 33% to 83%), specificity (97%, 95% CrI = 88% to 99%), and diagnostic odds ratio (42, 95% CrI = 8.08 to 249.8). For staging of distant metastases, PET-CT had the highest sensitivity (80%, 95% CrI = 53% to 93%), specificity (87%, 95% CrI = 54% to 97%), and diagnostic odds ratio (25, 95% CrI = 3.58 to 198.7). Similar trends were observed for melanoma surveillance of lymph node involvement, with ultrasonography having the highest sensitivity (96%, 95% CrI = 85% to 99%), specificity (99%, 95% CrI = 95% to 100%), and diagnostic odds ratio (1675, 95% CrI = 226.6 to 15,920). For distant metastases, PET-CT had the highest sensitivity (86%, 95% CrI = 76% to 93%), specificity (91%, 95% CrI = 79% to 97%), and diagnostic odds ratio (67, 95% CrI = 20.42 to 229.7). Positive predictive values were likewise highest for ultrasonography in lymph node staging and for PET-CT in detecting distant metastases.

CONCLUSION

Among the compared modalities, ultrasonography was superior for detecting lymph node metastases, and PET-CT was superior for the detection of distant metastases in both the staging and surveillance of melanoma patients.

Detection of melanoma nodal metastases; differences in detection between elderly and younger patients do not affect survival

BACKGROUND

Melanoma lymph nodes metastases may be detected by patients or by physicians. Understanding the outcomes of self-detection or physician detection is essential for the design of follow-up studies. We evaluated the role of the method of detection in nodal disease in the prognosis of melanoma patients who underwent therapeutic lymph node dissection (TLND).

MATERIALS AND METHODS

All melanoma patients with palpable lymph nodes were included in a prospective database (n = 98), and the method of detection was recorded. Detection of lymph node metastases compared with pathological findings in the TLND was assessed by multivariate logistic regression. Disease-free survival (DFS) and disease-specific survival (DSS) were assessed by univariate and multivariate Cox proportional hazard analysis.

RESULTS

Nodal metastases were detected by physicians in 45% and by patients in 55% (P < 0.001). Age was significantly associated with method of detection. Patients ≤60 years detected 69% their lymph node metastases as opposed to 32% of patients >60 years (odds ratio [OR] 0.3; P = 0.007). However, this was not associated with prognostic findings in TLND, number of positive nodes, tumor size, or extranodal spread. Method of detection or age at the time of nodal metastases was not significantly associated with 2-year DFS or DSS.

CONCLUSIONS

45% of all lymph node metastases in stage I-II melanoma patients are physician detected. Younger patients detect their own lymph node metastases significantly more often than elderly patients. However, neither the method of detection nor age correlates with DSS. More frequent follow-up would not alter DFS and DSS significantly.

[The status of domestic PET/CT attendance in the light of the waiting list data]

The aim of the study is to demonstrate the diagnostic and geographical distribution of the domestic PET/CT examinations financed by the OEP based on the data from the waiting list of the past 4 years. The analysis of the demonstrated data can support the rational usage of PET/CT examination contingents in the domestic oncological attendance, which has growing importance. PET examinations with oncological aims have started in Debrecen more than 10 years ago. In 2005 already 1500 PET examinations have been carried out. According to the governmental regulation accepted in 2006, OEP ensures the financing of the three PET/CT centers until 2012, which means 12,000 examinations in 2012. However, the number of domestic oncological patients requiring PET/CT examinations can reach the number of 20,000-30,000 patients. The study summarizes the number of patients who applied for PET/CT examinations for the first time and later again between 2006 and 2010, based on the data of the waiting list, and the change of the patient assigning diagnosis and the number of examinations carried out with 18F-FDG and with 11C-methionine. The study demonstrates the number of examinations by counties which characterize the population's access to PET/CT. The assigning diagnosis in 2007 was already widespread and focused on problems. After the regulation came in to force in 2008 the possibilities significantly decreased. Clinical cases which were efficiently examined with PET/CT earlier were left out from the indication list. The distribution by county is uneven, although the number of examinations increases year by year. The number of repeated examinations increases as well. As a conclusion, the annual PET/CT examination contingents are constantly exploited. This might seem sufficient, because the method has not become a part of the oncological routine in all counties. Although the current indication list includes the most frequent oncological cases requiring PET/CT, the abandoning of the less frequent ones narrowed the professional latitude, which is disadvantageous for the patients suffering from such diseases. The radiopharmacon supply of PET/CT centers is inadequate thus they cannot provide modern oncological diagnostic attendance in case of frequent types of cancer (such as prostate). In the long run the growing number of repeated PET/CT examinations built in the oncological professional protocol has to be taken into account.

PET Imaging for Traumatic Brain Injury

Traumatic brain injury represents a substantial public health problem for which clinicians have limited treatment avenues. Traditional FDG-positron emission tomography (PET) brain imaging has provided unique insights into this disease including prognostic information. With the advent and implementation of novel tracers as well as improvement in instrumentation, molecular brain imaging using PET can further illustrate traumatic brain injury pathophysiology and point to novel treatment strategies.

S-100B concentrations predict disease-free survival in stage III melanoma patients

BACKGROUND

Elevation of the tumor marker S-100B in melanoma patients is a highly specific indicator of recurrence.

MATERIALS AND METHODS

The role of S-100B in disease-free survival (DFS) was evaluated in stage III melanoma patients (staged with fluorodeoxyglucose positron emission tomography [FDG-PET] and computed tomography [CT]) with palpable lymph node metastases who underwent therapeutic lymph node dissection. S-100B and LDH were measured on the day before surgery (d = -1) and on days 1, 2, and 7 postoperatively. Multivariate logistic regression was used to study factors associated with preoperative elevation of S-100B. Univariate (log-rank test) and multivariate (Cox regression) survival analyses were performed to identify factors associated with DFS.

RESULTS

Between 2004 and 2008, 56 patients (median age 57, range 24-93) years, 27 males (48%) and 29 females (52%) entered the study. Preoperative S-100B elevation was found in 27 patients (48%) and elevated LDH in 20 patients (36%). No association was found between these two markers at any time. Multivariate analysis showed that elevated S-100B preoperatively (hazard ratio [HR] 2.7, P = .03) was associated with DFS. S-100B elevation was associated with increased tumor size (odds ratio [OR] 3.40; P = .03).

CONCLUSION

Elevated S-100B preoperatively in patients with optimally staged clinical stage III melanoma is associated with decreased disease-free survival. S100-B could be used as a prognostic marker in the stratification of new adjuvant trials to select stage III melanoma patients for adjuvant systematic treatment.

Hybrid imaging (SPECT/CT and PET/CT): improving therapeutic decisions

The incremental diagnostic value of integrated positron emission tomography-computed tomography (PET/CT) or single-photon emission computed tomography (SPECT)/CT images compared with PET or SPECT alone, or PET or SPECT correlated with a CT obtained at a different time includes the following: (1) improvement in lesion detection on both CT and PET or SPECT images, (2) improvement in the localization of foci of uptake resulting in better differentiation of physiological from pathologic uptake, (3) precise localization of the malignant foci, for example, in the skeleton vs soft tissue or liver vs adjacent bowel or node (4) characterization of serendipitous lesions, and (5) confirmation of small, subtle, or unusual lesions. The use of these techniques can occur at the time of initial diagnosis, in assessing the early response of disease to treatment, at the conclusion of treatment, and in continuing follow-up of patients. PET/CT and SPECT/CT fusion images affect the clinical management in a significant proportion of patients with a wide range of diseases by (1) guiding further procedures, (2) excluding the need of further procedures, (3) changing both inter- and intramodality therapy, including soon after treatment has been initiated, and (4) by providing prognostic information. PET/CT fusion images have the potential to provide important information to guide the biopsy of a mass to active regions of the tumor and to provide better maps than CT alone to modulate field and dose of radiation therapy. It is expected that the role of PET/CT and SPECT/CT in changing management will continue to evolve in the future and that these tools will be fundamental components of the truly "personalized medicine" we are striving to deliver.

Staging of cutaneous melanoma

The American Joint Committee on Cancer (AJCC) staging of cutaneous melanoma is a continuously evolving system. The identification of increasingly more accurate prognostic factors has led to major changes in melanoma staging over the years, and the current system described in this review will likely be modified in the near future. Likewise, application of new imaging techniques has also changed the staging work-up of patients with cutaneous melanoma. Chest and abdominal computed tomography (CT) scanning is most commonly used for evaluation of potential metastatic sites in the lungs, lymph nodes and liver, and is indicated in patients with new symptoms, anaemia, elevated lactate dehydrogenase or a chest X-ray abnormality. CT scans should be restricted to patients with high-risk melanoma (stage IIC, IIIB, IIIC and stage IIIA with a macroscopic sentinel lymph node). Magnetic resonance imaging (MRI) of the brain is a mandatory test in patients with stage IV, optional in stage III and not used in patients with stage I and II disease. Positron emission tomography (PET)/CT is more accurate than CT or MRI alone in the diagnosis of metastases and should complement conventional CT/MRI imaging in the staging work-up of patients who have solitary or oligometastatic disease where surgical resection is most relevant.

Whole body positron emission tomography in follow-up of high risk melanoma

The aim of this study was to determine the clinical impact of whole body positron emission tomography (FDG PET) to detect clinically silent metastases in the follow-up of patients with high risk melanoma. FDG PET was performed to 30 asymptomatic melanoma patients (AJCC stage IIB-IIIC) 7-24 months after the primary surgery and sentinel node biopsy. FDG PET was able to detect six of seven recurrences, constituting 20% of all study patients. One patient presented with a negative FDG PET finding at the very first scanning, but was positive later in a repeated scan after manifestation of palpable mass in the axilla. The positive PET finding had an impact on treatment decisions in every case: three patients underwent surgical resection and four patients received chemotherapy or interferon. The mean follow-up time was 27 months (range, 12-48 months) and during that time the other 23 patients with true negative FDG PET were disease-free. One of the seven recurrences was in remission after surgical metastasectomy. In conclusion, whole body FDG PET is a valuable follow-up tool in high risk melanoma to diagnose recurrences and to select the patients, who are suitable for surgical metastasectomy.

Imaging in cutaneous melanoma

Cutaneous melanoma (CM) is a common malignancy and imaging, particularly lymphoscintigraphy (LS), positron-emission tomography with 2-fluoro-2-deoxyglucose (FDG-PET), ultrasound, radiography computed tomography (CT) and magnetic resonance imaging have important roles in staging and restaging, surgical guidance, surveillance and assessment of recurrent disease. This review aims to summarize the available data regarding these and other imaging modalities in CM and provide the basis for subsequent formulation of guidelines regarding the use of imaging in CM. PubMed and Medline searches were performed and reference lists from publications were also searched. The published data were reviewed and tabulated. There is level I evidence supporting the use of LS and sentinel lymph node biopsy in nodal staging for CM. There is level III evidence demonstrating the superiority of ultrasound to palpation in the assessment of lymph nodes in CM. There is level IV evidence supporting FDG-PET in American Joint Committee on Cancer stage III/IV and recurrent CM and that FDG-PET/CT may be superior to FDG-PET. Level IV evidence also supports the use of CT in the same group of patients and the role of CT appears to be complementary to FDG-PET. Various imaging modalities, especially LS/sentinel lymph node biopsy and FDG-PET/CT, add incremental information in the management of CM and the various modalities have complementary roles depending on the clinical situation.

The European approach to in-transit melanoma lesions

The biological behavior of melanoma is unpredictable. Three to five per cent of melanoma patients will develop in-transit lesions and the median time to recurrence ranges between 13-16 months. At the time of recurrence the risk of occult nodal metastasis, with clinically negative regional lymph nodes, is as high as 50%. The risk of in-transit lesions depends on the tumor biology and not on the surgical approach to the regional lymph nodes. The high incidence of in-transit lesions at the lower limb may be caused by the gravity and delayed lymphatic drainage. The treatment of limited disease is local excision, laser ablation, cryosurgery, while multiple in-transit lesions or bulky disease located in a limb can be successfully treated with regional chemotherapy, a therapeutic isolated limb perfusion or infusion with melphalan or a combination of melphalan and tumor necrosis factor (TNF) alpha. If local regional treatment or systemic dacarbazine based systemic treatment fails, novel systemic treatment strategies with vaccines, antibodies and gene therapy are currently investigated.

Surgery for melanoma metastases of the gastrointestinal tract: indications and results

AIM

To assess survival, morbidity and mortality following therapeutic or palliative resection of gastrointestinal (GI) tract melanoma metastases.

METHODS

A retrospective case series of 117 patients who underwent surgical resection of GI melanoma metastases between 1981 and 2005 was reviewed.

RESULTS

The 117 patients underwent 142 operations for acute and/or sub-acute symptoms or for imminently symptomatic GI metastases detected radiologically. The intent of the surgery was palliative in 53 (37.3%) and therapeutic in 89 (62.7%) operations. The most common symptoms were due to anaemia (40.8%) or bowel obstruction (32.4%). The most frequently performed operation was small bowel resection (76.8%). Preoperative imaging and/or endoscopy were used in 83 cases, with computerised tomography (CT) being most frequent (85.5%). CT had a sensitivity of 68.8% when used alone to detect the presence of GI metastases in the study population. The mortality rate following GI resection was 1.4%, and 2.5% of patients had post-operative complications. Overall 5-year survival was 27%. On multivariate analysis, the presence of residual intraabdominal disease and the presence of non-GI metastases at the time of surgery or after surgery were the most significant prognostic indicators of survival.

CONCLUSIONS

Resection of GI melanoma metastases is safe, relieves symptoms and can achieve prolonged remission. In patients with limited disease, an aggressive surgical approach to symptomatic or imminently symptomatic GI melanoma metastases is warranted.

Multicentre assessment and monitored use of [18F]FDG-PET in oncology: the Spanish experience

PURPOSE

The aim of this study was to evaluate the diagnostic effectiveness of [(18)F]FDG-PET in oncological diseases and to assess its clinical utility and impact (on the clinical and therapeutic management of these patients). This health technology assessment was performed in Spain, using the monitored use (MU) procedure.

METHODS

A multicentre and prospective follow-up study was performed in a non-consecutive sample of oncological patients who were examined with PET and other conventional diagnostic tests. A protocol for this MU method (PET-MU protocol) was developed, including the three forms used to collect all the information. Enrollment of new patients began in June 2002 and continued until August 2004. A descriptive analysis and an evaluation of the diagnostic effectiveness of FDG-PET were performed.

RESULTS

The study population comprised 2,824 oncological patients (the third form relating to follow-up was completed for only 967 of these patients) from 100 Spanish hospitals and 16 PET centres. Seventy-nine percent of cases met the clinical requirements of the PET-MU protocol. Global diagnostic parameters of PET performance and their 95% CI values were as follows: sensitivity 86% (82-89%), specificity 83% (79-86%), positive and negative predictive values 87% (83-90%) and 82% (77-85%) respectively, diagnostic accuracy 84% (82-87%) and diagnostic odds ratio 28.75 (19.75-41.84). PET detected unsuspected new lesions in 39% of patients and avoided other unnecessary diagnostic techniques and treatments in 69% of cases. In 88% of cases, PET was considered useful by the physicians who asked for the PET tests (it was deemed decisive in 30% and very useful in almost 37%).

CONCLUSION

This PET-MU study has confirmed the high diagnostic effectiveness of FDG-PET for oncological indications and demonstrates that it has a great influence on the clinical and therapeutic management of patients.

Advances in metabolic imaging for surgical oncology

This review focuses on several aspects of molecular imaging. First, current positron emission tomography (PET)/CT scanner technology and several novel imaging techniques that are being developed are briefly discussed. Next, current clinical indications for (18)F FDG PET and PET/CT that are relevant to the surgical oncologist are discussed. Finally, advances in molecular imaging that may herald the next generation of PET radiotracers beyond (18)F FDG are reviewed.

Nuclear imaging of neuroendocrine tumours

The diagnosis of neuroendocrine tumours (NETs) and monitoring of therapy in many patients relies mainly on morphological imaging techniques such as computed tomography (CT), ultrasound (US) and magnetic resonance imaging (MRI). However, functional imaging modalities--such as somatostatin receptor scintigraphy (SRS)--have great impact on patient management by providing tools for better staging of the disease, visualization of occult tumour, and evaluation of eligibility for somatostatin analogue treatment. Positron emission tomography (PET) using (18)F-fluoro-deoxy-glucose (FDG) is a powerful functional modality for oncological imaging. Unfortunately, FDG is not accumulated in NETs except in the case of dedifferentiated tumours and tumours with high proliferative activity. Based on the concept of amine precursor uptake and decarboxylation (APUD), the (18)F- and (11)C-labelled amine precursors L-dihydroxyphenylalanine and 5-hydroxy-L-tryptophan (5-HTP) have been utilized for PET imaging of NETs. In comparative studies of patients with a variety of NETs, (11)C5-HTP-PET proved better than CT and SRS by visualizing additional small lesions. With carbidopa premedication orally before (11)C5-HTP-PET examination the tumour uptake could be increased and the urinary radioactivity concentration considerably reduced. This concept may also be applied to (18)F-L-DOPA-PET, a method which in a limited number of studies has gained additional diagnostic information in NET patients compared to SRS and morphological imaging. (68)Ga is available from an in-house generator and has been utilized for labelling of somatostatin analogues for PET imaging of NETs with promising results in a small number of patients. However, SRS is an established functional imaging method for patients with NETs, whereas the role for PET in the clinical routine needs further evaluation in comparative studies in larger groups of patients.

[Evaluation of efficacy and clinical impact of FDG-PET on patients with suspicion of recurrent cutaneous melanoma]

AIMS

To evaluate the efficacy and clinical impact of positron emission tomography with 18F-FDG (FDG-PET) in patients with suspected recurrent melanoma.

MATERIALS AND METHODS

We studied 105 patients with melanoma and suspicion of recurrent melanoma by clinical symptoms in 38 cases or equivocal/positives morphological tests (TC, MR, US) in 77 cases. In all patients a whole body scan was performed with FDG-PET (ECAT HR +) after an intravenous injection of 444-518 MBq of 18F-FDG, in normoglucemia conditions, and previous administration of muscular relaxant, hydration and diuretic. Images were evaluated by 2 dxpert nuclear physicians and were analysed qualitatively and semiquantitatively. In 48 cases the results were confirmed by histology and clinical evolution (follow-up period >12 months) and imaging tests in 57 cases.

RESULTS

Prevalence of recurrent melanoma was 63.8 %. Sensitivity, specificity, PPV, NPV and accuracy of FDG-PET was 97 %, 97.2 %, 98.5 %, 82 % y 94.7 % respectively. FDG-PET had led to a management change in 48 cases (38 %).

CONCLUSIONS

FDG-PET has high clinical impact in patients with suspicion of recurrent melanoma, and should be incorporated in the diagnosis protocols, before making therapeutic decision.

2-Deoxy-2-[F-18]fluoro-d-glucose Positron Emission Tomography/Computed Tomography in the Management of Melanoma

OBJECTIVES

2-Deoxy-2-[F-18]fluoro-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) is widely available as a powerful imaging modality, combining the ability to detect active metabolic processes and their morphologic features in a single exam. The role of FDG-PET is proven in a variety of cancers, including melanoma, but the estimates of sensitivity and specificity are based in the majority of the published studies on dedicated PET, not PET/CT. Therefore, we were prompted to review our experience with FDG-PET/CT in the management of melanoma.

METHODS

This is a retrospective study on 106 patients with melanoma (20-87 years old; average: 56.8 +/- 15.9), who had whole-body FDG-PET/CT at our institution from January 2003 to June 2005. Thirty-eight patients (35.9%) were women and 68 patients (64.1%) were men. Reinterpretation of the imaging studies for accuracy and data analysis from medical records were performed.

RESULTS

All patients had the study for disease restaging. The primary tumor depth (Breslow's thickness) at initial diagnosis was available for 76 patients (71.7%) and ranged from 0.4 to 25 mm (average: 3.56 mm). The anatomic level of invasion in the skin (Clark's level) was determined for 70 patients (66%): 3, level II; 13, level III; 43, level IV; 11, level V. The administered dose of (18)F FDG ranged from 9.8 to 21.6 mCi (average: 15.4 +/- 1.8 mCi). FDG-PET/CT had a sensitivity of 89.3% [95% confidence interval (CI): 78.5-95] and a specificity of 88% (95% CI: 76.2-94.4) for melanoma detection.

CONCLUSION

This study confirms the good results of FDG-PET/CT for residual/recurrent melanoma detection, as well as for distant metastases localization. PET/CT should be an integral part in evaluation of patients with high-risk melanoma, prior to selection of the most appropriate therapy.

Commonly used imaging techniques for diagnosis and staging

Imaging plays a vital role in the management of patients with cancer. Not only is it important for diagnosis, indicating sites of abnormality, and guiding biopsies, but it is also crucial in assessing disease extent and thereby determining treatment. In this review, conventional imaging techniques such as ultrasound, computed tomography, magnetic resonance imaging, and [18F]fluorodeoxyglucose-positron emission tomography are described, with attention to their mechanisms of action, and their strengths and weaknesses in diagnosis and staging of tumors. New developments are addressed and radiation safety issues are highlighted. In addition, we describe current and expected future uses of imaging techniques in oncology. Given that each technique has its inherent strengths and weaknesses, the combination of the methods will result in improved diagnosis, staging, and treatment prediction and monitoring.

Level of Fluorodeoxyglucose Uptake Predicts Risk for Recurrence in Melanoma Patients Presenting With Lymph Node Metastases

BACKGROUND

The incidence of malignant melanoma has increased. Identification of additional prognostic factors may allow the development of individualized strategies. This multivariate analysis was undertaken to evaluate the potential role of the standard uptake value (SUV) in predicting disease-free and overall survival in melanoma patients with lymph node metastases.

METHODS

All melanoma patients with palpable lymph node metastases who where referred for a fluorodeoxyglucose positron emission tomography scan were eligible. The SUV in the lymph node metastasis was calculated. Data were analyzed (Kaplan-Meier), and differences in cumulative survival and the disease-free rate were assessed (log-rank test). Univariate and multivariate analyses (Cox proportional hazard model) were performed to determine independent prognostic factors.

RESULTS

There was no statistical difference in survival for the 38 patients with a high or low SUVmean (P = .11). However, a significant difference was found in disease-free survival (P = .03). Ulceration of the primary melanoma (P = .023) was an independent predictor of survival. For the disease-free survival, multivariate Cox regression showed adjuvant radiation (P = .001), localization of the primary melanoma (P = .017), and a high SUVmean (P = .009) as independent prognostic factors.

CONCLUSIONS

Disease-free survival of melanoma patients was prolonged in those with a low SUVmean value (P = .03) in their lymph node metastasis, as compared with those with a high SUVmean. However, this difference was not found for overall survival. In multivariate analysis, high SUVmean was an independent prognostic factor (P = .009) for disease-free survival. Prospective research should determine whether patients with a high FDG uptake in melanoma lymph node metastases could benefit from adjuvant radiation treatment or chemotherapy.