Indium-111-DTPA-octreotide Scintigraphy Modulation by Treatment with Unlabelled Somatostatin Analogue in Smali-Cell Lung Cancer

Aims and background

Small-cell lung cancer (SCLC) tissue expresses somatostatin receptors and can be visualized by means of the indium-111-labelled somatostatin analogue DTPA-D-Pheoctreotide. The aim of the study was to investigate whether treatment with a cold somatostatin analogue can affect the imaging of somatostatin receptor scintigraphy.

Methods

Three patients with SCLC were treated with 200 μg of cold octreotide three times a day subcutaneously for 7 days. Whole body and planar scintigraphy was performed before and after the treatment.

Results

111In-DTPA-octreotide uptake was increased in cancer lesions, whereas fixation in normal tissues (liver, spleen, kidneys) decreased.

Conclusions

This is the first demonstration of an enhancement of SCLC imaging following unlabelled somatostatin analogue administration. Similar results have been described by other authors in a limited number of carcinoid tumors.

Association of Cea Test and Liver Scan in Detection of Hepatic Metastases of Gastrointestinal Carcinoma

The authors evaluate the combined use of liver scan and the CEA test in the diagnosis of hepatic metastases of carcinoma of the gastrointestinal tract. Association of the two tests is justified by the fact that the liver scan is very specific but not very sensitive, whereas the CEA test is more sensitive and not very specific. The sensitivity of the CEA test, on the other hand, can be increased by increasing the threshold of normality. However, the associated diagnostic use of the liver scan and the CEA test gives a loss of specificity with respect to the use of the liver scan alone. The present study, carried out on a series of 376 patients affected by gastrointestinal tumors of which 79 were of the stomach (9 with hepatic metastases), 133 of the colon and higher sigmoid (25 with hepatic metastases), and 164 of the lower sigmoid and rectum (29 with hepatic metastases), proposed to establish by use of a statistical method the optimal threshold of the CEA test that would give the best diagnostic specificity of the combined CEA test and liver scan without any relevant loss of sensitivity. A threshold of 26 ng/ml of the CEA test gave a specificity of 92 %, a sensitivity of 80 %, and an accuracy of 90 %. The authors think that in the detection of liver metastases of gastrointestinal tumors, the combined test can be more helpful the less the probability, for a given patient, for other metastatic localizations.

Mitoxantrone as First-Salvage Chemotherapy in Relapsed Breast Cancer

Mitoxantrone was administered at the dose of 14 mg/m2 i.v. every 3 weeks to 25 consecutive women with measurable progressive disease who relapsed after adjuvant CMF and endocrine therapy. The treatment plan consisted in the delivery of 6 cycles, unless disease progression or severe toxicity occurred. All patients were evaluable for drug response and toxicity. One patient achieved complete remission and 6 partial remission, for a total response rate of 28%. Objective tumor response was observed in all major sites of disease. The median time to achieve remission was 3 months. The median duration of response was 7 months (range, 5–39+), and the median survival for the entire group was 10 months (range, 3–39). Results were influenced only by the duration of diseasefree status from the end of adjuvant CMF chemotherapy. In fact, all tumor responses were documented in woman with free intervals exceeding 1 year (7 of 17 or 41 %). Treatment was generally well tolerated, with 10 patients developing leukopenia at some time during treatment. Only 2 patients received less than 75 % of the projected dose because of granulocytopenia. Complete alopecia occurred in only 2 cases. Three patients developed a fall > 15 % in left ventricular ejection fraction, but no episode of congestive heart failure was observed. We conclude that mitoxantrone is an effective and safe drug which can be utilized in women relapsing after adjuvant CMF.

Clinical Value of Radioimmunoscintigraphy in the follow-up of Ovarian Carcinoma: A Prospective Study

Twenty-five patients treated with debulking surgery and chemotherapy for ovarian cancer were prospectively studied to evaluate the efficacy of radioimmunoscintigraphy (RIS) in detecting residual tumor before second-look surgery. RIS was performed with the monoclonal antibody OC125 F(ab')2 labelled with 1-131 without knowledge of clinical data and compared with subsequent surgical results. Second look showed tumor persistence in 12 patients, mostly characterized by small lesions. The overall diagnostic sensitivity of RIS was 50% and the specificity was 85%. In particular, RIS showed better sensitivity for pelvic tumor localizations than for abdominal sites (73% vs 33%); this was due to the inability of RIS to detect upper abdominal lesions. Therefore, our conclusion is that, at present, RIS cannot substitute surgical second-look in the management of ovarian cancer, however, considering that also ultrasonography, computer tomography and magnetic resonance are not always able to give definite diagnostic evidence in the follow-up of ovarian carcinoma, RIS could be added to these procedures to balance the limitations of each method. In this regard, the best application of RIS could be in the follow-up of patients with marker elevation without clinical evidence of disease, especially in the case of pelvic fibrosis or adhesions due to previous therapy, where the other non-invasive tools can give doubtful diagnostic results.

Radioimmunotherapy of Ovarian Cancer

Radioimmunotherapy (RIT) is a new therapeutical approach where radiolabeled monoclonal antibodies (MAb) against tumor-associated antigens are administered to treat tumor lesions. Ovarian cancer is one of the most promising fields for RIT. This paper gives an overview of some biodistribution studies in animal models and in patients with radiolabeled anti-ovarian cancer MAbs, and defines the main criteria which should be considered to plan a clinical trial of RIT in ovarian cancer. As regards the clinical results, the published outcome of various trials and the experience of the National Cancer Institute of Milan are summarized. Even if the number of patients involved in these clinical studies of RIT is too small to provide conclusive indications about its role in the management of ovarian cancer, the preliminary results from qualified groups show its potential in this disease despite the current problems that limit clinical application (above all, the instability of the radiolabeled linkage, the immunogenicity of murine antibodies, the poor absolute tumor radiolabel uptake and the bone marrow toxicity).

The Influence of Blood Glucose Levels on [18F]Fluorodeoxyglucose (Fdg) Uptake in Cancer: A Pet Study in Liver Metastases from Colorectal Carcinomas

Aims and background

To study the influence of blood glucose levels on the clinical reliability of positron emission tomography (PET) with [18F]-2-fluoro-2-deoxy-D-glucose (FDG) in the detection of liver metastases from colorectal carcinomas and in the analysis of tumor uptake of FDG.

Methods

After having given their informed consent, 8 patients with 20 liver metastases (mean size, 31.5 mm; range, 10–75 mm) detected by means of CT were submitted to a first FDG-PET examination under fasting conditions and, 2 days later, to a second FDG-PET examination performed after iv infusion of a glucose solution (4 mg/kg/min for 2 hrs). The results of the two studies were compared in each patient, considering both the localization of the metastases and the FDG uptake in the lesions. A non-kinetic method was used, calculating the Standardized Uptake Value (SUV).

Results

All 20 metastases were clearly visible on FDG-PET under fasting conditions. Moreover, in 2 patients FDG-PET detected a number of unknown liver metastases. The blood glucose levels after glucose infusion were significantly higher than the levels under fasting conditions, 158 ± 13.8 mg/100 ml (mean ± sd) and 92.4 ± 10.2, respectively (P « 0.001), and the quality of the FDG-PET images showed a marked deterioration. FDG-PET was unable to detect 6 of the 20 lesions and another 10 lesions were localized less clearly. Moreover, 80% of the unknown liver metastases were not detected after glucose loading. The SUVs of metastases decreased from 9.4 ± 5.7 (mean ± sd) under fasting conditions to 4.3 ± 8.3 after glucose loading (P « 0.001).

Conclusions

FDG-PET studies may be particularly unreliable under conditions of high levels of blood glucose. Therefore, patients entering FDG-PET studies should fast, and blood glucose concentration needs to be taken into account when evaluating FDG uptakes in follow-up studies.

Nuclear Medicine Advances in Breast Cancer Imaging

Primary breast cancer imaging can be done by various means. Mammography is the most widely used technique because of its excellent diagnostic performance, patient compliance, and cost-effectiveness ratio. Other radiological techniques (such as ultrasonography) are indicated in particular circumstances, while some (such as digital mammography and magnetic resonance imaging) seem very promising but are still under evaluation. The recent technological progress in nuclear medicine has resulted in the availability of two diagnostic procedures that have been validated by extensive international clinical experience: scintimammography with Ses-ta-MIBI and positron emission tomography (PET) with fluorodeoxyglucose (FDG). The general advantage of nuclear medicine imaging is that tumor-seeking radiopharmaceuticals accumulate in cancer lesions, which makes scintimammography and PET fundamentally different from the radiological techniques that image the tumor mainly on the basis of morphological alterations. Scintimammography is indicated for the study of breast lesions in patients in whom mammography is non-diagnostic or difficult to interpret; it may be useful also to assess and even predict the response to primary chemotherapy. FDG-PET is increasingly used in oncology and is particularly useful in breast cancer as it gives more accurate information than scintimammography in the evaluation of patients with ambiguous mammographies and in discriminating between viable tumor, fibrotic scar or necrosis following surgery, chemo- or radiotherapy. The FDG uptake in the tumor correlates with the histological grade and potential aggressiveness of breast cancer, which may have prognostic implications. In addition to its usefulness in the study of breast lesions, FDG-PET shows great efficacy in detecting lymph node involvement prior to surgery. Whole-body PET provides information on soft tissue and bone metastases in a single scanning session, and has an important clinical role in detecting recurrent metastatic disease. On the basis of the above-mentioned evidence, nuclear medicine techniques, integrated with radiological techniques, offer an interesting opportunity to improve the diagnostic imaging yield in breast cancer, which will eventually lead to better patient management. This paper reports on the latest developments in this field.

Mucin-Like Carcinoma-Associated Antigen (MCA) in Breast Cancer: Clinical Experience at the National Cancer Institute of Milan

Mucin-like Carcinoma-associated Antigen (MCA) is a glycoprotein belonging to the mucin family; it is defined by the monoclonal antibody b-12. Mucins represent an interesting group of tumor markers and are widely utilized in the clinical monitoring of neoplastic patients. These molecules show a certain degree of tissue specificity and MCA is preferentially associated with breast tissue.

Several studies have demonstrated that patients with breast cancer usually have high MCA serum levels. In this paper the experience of the National Cancer Institute of Milan with the clinical use of MCA in breast cancer patients is reported. The observed sensitivity of the MCA test was poor in patients with early-stage disease, while it was acceptable in patients with advanced breast cancer. MCA concentrations appeared to be directly related to disease spread. A clear relationship was seen between MCA levels and lymph-nodal status. The highest MCA plasma levels were observed in patients with metastatic disease. In this group of patients the sensitivity of the test on the basis of a cut-off of 11 U/mL was 52%.

The Role of Serum Carcinoembryonic Antigen (CEA) in the Management of Patients with Colorectal Carcinoma: The Experience of the Istituto Tumori of Milan

CEA determination has attained an important role in the clinical management of patients with tumors of the colorectal tract. In this paper the experience of the Istituto Tumori of Milan is reviewed and the results are discussed. Three hundred and thirty-six patients were followed after curative resection of colorectal carcinoma. The follow-up period was 15 years, from January 1975 to December 1990 (global follow-up 1358 years). In the course of follow-up 136 patients developed recurrent disease. The number of CEA determinations for each patient ranged from 1 to 37 (mean 8, total 3330). CEA levels of presurgical patients were related to the clinical stage. Among patients who developed recurrences 61% showed an increase in CEA serum levels. In 200 patients with a negative follow-up we observed only 15 cases of false-positive results.

Preliminary Study on Serum Levels of Mucinous like Cancer Antigen (MCA) in Patients with Breast Disease: Comparison with CEA

MCA (mucinous-like cancer antigen) can be measured in the biological fluids of patients by means of a solid phase enzyme immunoassay. This study describes the results of MCA determination in sera of 230 patients with benign (99) and malignant (131) breast diseases. MCA levels were significantly higher in breast cancer patients than in non cancer patients and in healthy subjects (p < 0.001). MCA concentrations tended to increase as the stage of the disease advanced. The 95th percentile of MCA value distribution in normal subjects showed a diagnostic sensitivity in breast cancer patients of 16.3% at stage I,26.2% at stages II-III and 52% at stage IV. In a group of 118 cancer patients, MCA and CEA were tested simultaneously. The diagnostic sensitivity and specificity of MCA and CEA assays was very similar; nevertheless the association of the two tests showed 11 cases with high levels of MCA and low levels of CEA and 9 patients with high levels of CEA and low levels of MCA. Seventy-four out of 118 patients were negative for both markers and in 22 out of 118 patients markers were positive. The new marker MCA appeared to correlate with breast cancer and gave different information complementary to CEA.

TANCLICO: Tools for the Analysis of Inter-departmental Clinical Communications

Patient care management provided by healthcare organizations is complex, involving many different care providers. The information exchange between providers concerns a varying and considerable number of actors and a high transmission load. Based on models, used to characterize specific features of work processes, we propose a new method able to analyze and represent clinical communications inside hospitals. Software has been developed, providing tools for storing and retrieving information resulting from clinical communications. The method, together with data collected in actual situations, may constitute useful tools for health information systems developers.

Early reduction of serum TARC levels may predict for success of ABVD as frontline treatment in patients with Hodgkin Lymphoma

BACKGROUND

Many efforts have been made to predict prognosis of newly diagnosed Hodgkin Lymphoma (HL) patients. Objective of this study was to investigate the association between early reduction of Thymus and Activation-Regulated Chemokine after the first ABVD cycle (TARC-1) and prognosis of HL patients.

METHODS

Serum samples of 116 HL patients were collected at baseline, after every ABVD cycle and during follow-up. The 99th centile of TARC distribution in a group of 156 independent healthy subjects (800pg/ml) was considered as cut-off for discriminating between abnormal and normal TARC values.

FINDINGS

101 patients out of 116 had baseline TARC above 800pg/ml (median value 27515pg/ml (IQR, 11001-68139)) and were the object of this analysis. TARC-1 significantly decreased to a median value of 556pg/ml (IQR, 378-977pg/ml). TARC-1 values below 800pg/ml were associated with success of therapy (p=0.0003) and PET-2 negativity (p=0.001). TARC-1≤800pg/ml identified a population with a significantly higher 5-years PFS in the whole cohort (90.1% vs 55.6%; p<0.0001) and in both subgroups of advanced (p=0.003) and early stage patients (p=0.021). At multivariable analysis, TARC-1 was significant independent predictor of PFS (p=0.0035).

INTERPRETATION

Early reduction of TARC serum levels can predict success of treatment, being associated with achievement of interim PET-2 negative and favorable long-term outcome in HL patients receiving ABVD as front-line therapy.

A lock-in-based method to examine the thermal signatures of magnetic nanoparticles in the liquid, solid and aggregated states

We propose a new methodology based on lock-in thermography to study and quantify the heating power of magnetic nanoparticles. Superparamagnetic iron oxide nanoparticles exposed to a modulated alternating magnetic field were used as model materials to demonstrate the potency of the system. Both quantitative and qualitative information on their respective heating power was extracted at high thermal resolutions under increasingly complex conditions, including nanoparticles in the liquid, solid and aggregated states. Compared to conventional techniques, this approach offers a fast, sensitive and non-intrusive alternative to investigate multiple and dilute specimens simultaneously, which is essential for optimizing and accelerating screening procedures and comparative studies.

Radioembolization of hepatocarcinoma with (90)Y glass microspheres: development of an individualized treatment planning strategy based on dosimetry and radiobiology

PURPOSE

The aim of this study was to optimize the dosimetric approach and to review the absorbed doses delivered, taking into account radiobiology, in order to identify the optimal methodology for an individualized treatment planning strategy based on (99m)Tc-macroaggregated albumin (MAA) single photon emission computed tomography (SPECT) images.

METHODS

We performed retrospective dosimetry of the standard TheraSphere® treatment on 52 intermediate (n = 17) and advanced (i.e. portal vein thrombosis, n = 35) hepatocarcinoma patients with tumour burden < 50% and without obstruction of the main portal vein trunk. Response was monitored with the densitometric radiological criterion (European Association for the Study of the Liver) and treatment-related liver decompensation was defined ad hoc with a time cut-off of 6 months. Adverse events clearly attributable to disease progression or other causes were not attributed to treatment. Voxel dosimetry was performed with the local deposition method on (99m)Tc-MAA SPECT images. The reconstruction protocol was optimized. Concordance of (99m)Tc-MAA and (90)Y bremsstrahlung microsphere biodistributions was studied in 35 sequential patients. Two segmentation methods were used, based on SPECT alone (home-made code) or on coregistered SPECT/CT images (IMALYTICS™ by Philips). STRATOS™ absorbed dose calculation was validated for (90)Y with a single time point. Radiobiology was used introducing other dosimetric variables besides the mean absorbed dose D: equivalent uniform dose (EUD), biologically effective dose averaged over voxel values (BEDave) and equivalent uniform biologically effective dose (EUBED). Two sets of radiobiological parameters, the first derived from microsphere irradiation and the second from external beam radiotherapy (EBRT), were used. A total of 16 possible methodologies were compared. Tumour control probability (TCP) and normal tissue complication probability (NTCP) were derived. The area under the curve (AUC) of the receiver-operating characteristic (ROC) curve was used as a figure of merit to identify the methodology which gave the best separation in terms of dosimetry between responding and non-responding lesions and liver decompensated vs non-decompensated liver treatment.

RESULTS

MAA and (90)Y biodistributions were not different (71% of cases), different in 23% and uncertain in 6%. Response correlated with absorbed dose (Spearman's r from 0.48 to 0.69). Responding vs non-responding lesion absorbed doses were well separated, regardless of the methodology adopted (p = 0.0001, AUC from 0.75 to 0.87). EUBED gave significantly better separation with respect to mean dose (AUC = 0.87 vs 0.80, z = 2.07). Segmentation on SPECT gave better separation than on SPECT/CT. TCP(50%) was at 250 Gy for small lesion volumes (<10 cc) and higher than 1,000 Gy for large lesions (>10 cc). Apparent radiosensitivity values from TCP were around 0.003/Gy, a factor of 3-5 lower than in EBRT, as found by other authors. The dose-rate effect was negligible: a purely linear model can be applied. Toxicity incidence was significantly larger for Child B7 patients (89 vs 14%, p < 0.0001), who were therefore excluded from dose-toxicity analysis. Child A toxic vs non-toxic treatments were significantly separated in terms of dose averaged on whole non-tumoural parenchyma (including non-irradiated regions) with AUC from 0.73 to 0.94. TD50 was ≈ 100 Gy. No methodology was superior to parenchyma mean dose, which therefore can be used for planning, with a limit of TD15 ≈ 75 Gy.

CONCLUSION

A dosimetric treatment planning criterion for Child A patients without complete obstruction of the portal vein was developed.

Activity of sunitinib in extraskeletal myxoid chondrosarcoma

BACKGROUND

Extraskeletal myxoid chondrosarcoma (EMC) is a rare soft tissue sarcoma, marked by NR4A3 rearrangement. Herein we report on the activity of sunitinib in a series of 10 patients, strengthening what initially observed in two cases.

PATIENTS AND METHODS

From July 2011, 10 patients with progressive metastatic translocated EMC have been consecutively treated with sunitinib 37.5mg/day, on a named-use basis. In an attempt to interpret the activity of sunitinib in EMC, genotype/phenotype correlations were carried out by fluorescence in situ hybridization (FISH) analyses. Moreover, transcriptome, immunohistochemical and biochemical analyses of a limited set of samples were performed focusing on some putative targets of sunitinib.

RESULTS

Eight of 10 patients are still on therapy. Six patients had a Response Evaluation Criteria in Solid Tumours (RECIST) partial response (PR), two were stable, two progressed. Positron emission tomography (PET) was consistent in 6/6 evaluable cases. One patient underwent surgery after sunitinib, with evidence of a pathologic response. At a median follow-up of 8.5 months (range 2-28), no secondary resistance was detected. Median progression free survival (PFS) has not been reached. Interestingly, all responsive cases turned out to express the typical EWSR1-NR4A3 fusion, while refractory cases carried the alternative TAF15-NR4A3 fusion. Among putative sunitinib targets, only RET was expressed and activated in analysed samples.

CONCLUSIONS

This report confirms the therapeutic activity of sunitinib in EMC. Genotype/phenotype analyses support a correlation between response and EWSR1-NR4A3 fusion. Involvement of RET deserves further investigation.

PF-03446962, a fully-human monoclonal antibody against transforming growth-factor β (TGFβ) receptor ALK1, in pre-treated patients with urothelial cancer: an open label, single-group, phase 2 trial

Despite a compelling preclinical rationale for the use of anti-angiogenic drugs in urothelial cancer (UC), short-living responses have been observed in clinical trials. PF-03446962 is a novel monoclonal antibody against Activin Receptor-Like Kinase-1 (ALK1), a type I subclass of the TGFβ receptor, with dose-dependent anti-angiogenic activity. An open label, single-group, phase 2 trial of PF-03446962 was conducted in salvage setting. Patients failing at least one chemotherapy regimen were eligible. Design provided PF-03446962 10 mg/Kg intravenously fortnightly until disease progression (PD) or unacceptable toxicity. Two-month progression-free survival (PFS) was the primary endpoint. The trial was registered with ClinicalTrials.gov, number NCT01620970. Fourteen patients were enrolled from October 2012 to July 2013. Median age was 64 years (interquartile range [IQR]: 58.2-69.5), 9 patients had a Bellmunt score of 1-2, median number of prior drugs was 3. One stable disease and 13 PD were recorded and the study met the futility stopping rule of interim analysis. Median PFS was 1.8 months (95 %CI, 1.4-2.0). After a median follow up of 7.4 months (IQR 4.5-10.9), 8 patients are alive. Median overall survival (OS) was 8 months (95 %CI, 2.9-not estimable). Most common toxicities were thrombocytopenia (G1-2 in 5 cases, persistent G3 in one, with 3 dose delays and 1 dose interruption), fatigue and abdominal pain (G1-2 in 4 cases each). Impairment of quality of life (ESAS score) was observed as well as an increase from baseline to +2 month median levels of vascular endothelial growth factor (VEGF) and interleukin-8. PF-03446962 had no activity as single drug in refractory UC and we do not recommend further investigation outside of the combination with agents targeting the VEGF receptor axis.

Phase II study on lapatinib in advanced EGFR-positive chordoma

BACKGROUND

To report on a prospective, investigator-driven, phase II study on lapatinib in epidermal growth factor receptor (EGFR)-positive advanced chordoma patients.

PATIENTS AND METHODS

From December 2009 to January 2012, 18 advanced progressing chordoma patients entered this study (median age: 61 years; disease extent: metastatic 72% and locally advanced 28%). Epidermal growth factor receptor (EGFR) expression and activation were evaluated by immunohistochemistry and/or phospho-arrays, real-time polimerase chain reaction, fluorescence immunostaining. Fluorescence in situ hybridization analysis was also carried out. Patients received lapatinib 1500 mg/day (mean dose intensity = 1282 mg/day), until progression or toxicity. The primary study end point was response rate (RR) as per Choi criteria. Secondary end points were RR by Response Evaluation Criteria in Solid Tumor (RECIST), overall survival, progression-free survival (PFS) and clinical benefit rate (CBR; RECIST complete response + partial response (PR) + stable disease (SD) ≥ 6 months).

RESULTS

All patients were evaluable for response. Six (33.3%) patients had PR and 7 (38.9%) SD, as their best Choi responses, corresponding to RECIST SD in all cases. Median PFS by Choi was 6 [interquartile (IQ) range 3-8] months. Median PFS by RECIST was 8 (IQ range 4-12) months, with a 22% CBR.

CONCLUSIONS

This phase II study showed a modest antitumor activity of lapatinib in chordoma. The clinical exploitation of EGFR targeting in chordoma needs to be further investigated, both clinically and preclinically. Clinical trial Registration No: EU Clinical Trials Register trial no. 2009-014456-29.

Axillary lymph node metastases detection with nuclear medicine approaches in patients with newly diagnosed breast cancer

Three different tracers, Tc-99m-Sesta MIBI, In-111-Pentetreotide and F-18-FDG, were evaluated in a preliminary study in three different groups of 10 breast cancer patients programmed for breast cancer resection and axillary dissection. Planar scintigraphy and single photon emission tomography (SPET) technique were used for imaging with Tc-99m-Sesta-MIBI and In-111-Pentetreotide, positron emission tomography (PET) was used for imaging with F-18-FDG. We studied 30 breast cancer patients; their clinical stage according to the TNM classification was 30 T1-T2, 1 T4 and 1 Tx (one patient had bilateral cancer and one had bifocal cancer). The lymph nodal status ranged from NO to N2 (14 NO, 16 N1, 1 N2). Tc-99m-Sesta MIBI, In-111 Pentetreotide SPET and F-18-FDG PET were randomly performed before surgery to visualize the primary tumors and to detect axillary lymph node invasion. Tc-99m-Sesta MIBI correctly visualized 10 out of 11 primary cancers in 10 patients. In-111-Pentetreotide detected 9 out of 10 primary cancers. F-18-FDG imaged all the tumors (10). As regards the axillary nodes, Tc-99m-MIBI excluded axilla involvement in 7 out of 7 negative axillae (N-), while it was positive in 2 out of 3 positive cases (N+); In-111-Pentetreotide correctly identified 7 out of 8 negative axillae (N-), while it detected 2 of 3 positive sites. F-18-FDG visualized all positive axillary lymph nodes (4 out of 4 N+ patients) and correctly excluded involvement in all negative patients (6 out of 6 N- cases). This study demonstrated that all three tracers are adequate to be proposed as tumor seeking agents with the aim of developing non-invasive diagnostic methods for pre-operative detection of axillary metastases, so that surgical dissection can be limited to selected patients. The authors discuss the advantages and disadvantages of the different radiopharmaceuticals and conclude that in centers with PET facilities F-18-FDG is the best tumor seeking agent for the evaluation of axillary status. Between Tc-99m-Sesta MIBI and In-111-Pentetreotide the former seems to present more advantages in this kind of application, considering also its lower cost and easier availability. These results encourage further study, including the simultaneous comparison of these tracers in breast cancer staging.

PET with radiolabeled aminoacid

Since the clinical introduction of FDG, neuroimaging has been the first area of PET application in oncology. Later, while FDG-PET became progressively a key imaging modality in the management of the majority of malignancies outside the brain, its neuro-oncologic indications faced some limitations because of the unfavourable characteristics of FDG as brain tumor-seeking agent. PET applications in neuro-oncology have received new effectiveness by the advent of positron-emission labelled amino acids, so that it has been coined the term "Amino acid PET" to differentiate this imaging tool from FDG-PET. Radiolabeled amino acids are a very interesting class of PET tracers with great diagnostic potential in neuro-oncology because of their low uptake in normal brain and, conversely, high uptake in most brain tumors including low-grade gliomas. The present article surveys the results obtained using L-[methyl-11C]Methionine (MET), that has been the ancestor of PET amino acid tracers and is still the most popular amino acid imaging modality in oncology, and stresses the important role that this diagnostic modality can play in the evaluation of brain tumors. However, the use of MET is restricted to PET centers with an in-house cyclotron and radiochemistry facility, because of the short half-life (20 min) of 11C. The promising results of MET have stimulated the development of 18F-labelled aminoacid tracers, particularly O-(2-18F-fluoeoethyl1)-L-tyrosine (FET), that has the same properties of MET and, thanks to the longer half-life of 18F (about 110 min), allows a distribution strategy from a production tracer site to user satellite PET centers. Considering a more widespread use of Amino acid PET, together with the recent development of integrated PET-MRI imaging systems, and the oncoming clinical validation of other interesting PET tracers, i.e. FMISO or 18F-FAZA for hypoxia imaging and FLT for tumor proliferation imaging, it can be reasonably expected that metabolic imaging with PET is close to becoming a key diagnostic modality in the management of brain tumors, as has already been for Total Body FDG-PET/CT in extra-brain oncology.

Response to imatinib plus sirolimus in advanced chordoma

BACKGROUND

Imatinib (IM) is active in advanced chordoma. The evidence of upstream and/or downstream mammalian target of rapamycin (mTOR) pathway activation prompted us to combine an mTOR inhibitor, sirolimus, to IM in IM-resistant advanced chordoma.

PATIENTS AND METHODS

Since July 2007, 10 progressive advanced chordoma patients with secondary resistance to IM, and biochemical and/or immunohistochemical evidence of upstream and/or downstream mTOR effector activation, started IM (400 mg/day) plus sirolimus (2 mg/day) on a named basis.

RESULTS

The mean treatment duration was 9 months. Of nine patients assessable for response, at 3 months, we had one RECIST partial response (PR), seven stable disease (SD) and one progressive disease (PD). According to Choi criteria applied even to magnetic resonance imaging, we had seven PR (> or =10% decrease in size in four cases), one SD and one PD. Seven patients had a positron emission tomography response. The clinical benefit [RECIST complete response + PR + SD > or =6 months] was 89%. Pretreatment mTOR effectors analysis carried out in nine cases was positive in all patients (AKT activation in six patients, S6Sp6 expression/activation in seven). Post-treatment biopsy in one responsive patient confirmed S6 switch off.

CONCLUSION

In addition to PDGFRB, mTOR pathway can be activated in chordomas and the combination of IM plus rapalogs may be effective in IM-resistant chordomas.

Point mutations and a large intragenic deletion in SPG11 in complicated spastic paraplegia without thin corpus callosum

BACKGROUND

Hereditary spastic paraplegia (HSP) with thin corpus callosum (HSP-TCC) is a frequent subtype of complicated HSP clinically characterised by slowly progressive spastic paraparesis with cognitive impairment and thin corpus callosum (TCC). SPG11, the gene associated with the major locus involved, encodes spatacsin, a protein of unknown function.

METHODS

Different types of mutations were identified in patients with the complex form of HSP (cHSP) including TCC. We screened a series of 45 index patients with different types of cHSP with (n = 10) and without (n = 35) TCC.

RESULTS

Ten mutations, of which five are novel, were detected in seven patients. Of importance, three out of seven mutated patients present with cHSP without TCC. Among the novel mutations identified, we characterised a large intragenic rearrangement deleting 2.6 kb of the SPG11 gene. The rearrangement is due to non-allelic homologous recombination between Alu sequences flanking the breakpoints.

CONCLUSIONS

These findings expand the mutation spectrum of SPG11 and suggest that SPG11 mutations may occur more frequently in familial than sporadic forms of cHSP without TCC. This helps to define further clinical and molecular criteria for a correct diagnosis of the SPG11 related form of cHSP. In addition, the intragenic deletion detected here, and the mechanism involved, both provide clues to address the issue of SPG11 missing mutant alleles previously reported.

Imatinib mesylate in advanced chordoma: A multicenter phase II study

10003

Background: The antitumor activity of Imatinib in chordoma was preliminarily shown in a compassionate series of 18 pts. This prospective Phase II collaborative study was planned thereafter. Methods: From November 2004 to April 2006, 55 pts with progressing advanced chordoma were enrolled in this Phase II study. Cases were provided by 13 Italian centers and one Swiss. Imatinib was given at the planned dose of 800 mg/day (for a received dose intensity in excess of 600 mg/day), until evidence of progression. Mean age was 59 yrs, (range 24–86); PS 0–3 (=2 in 22%); site of origin was the sacrum in 60%, spine in 25%, skull base in 15%; the disease was metastatic in 43% and localized advanced in 57%. All tumors were positive for PDGFRB/PDGFB. Results: In 44 pts evaluable for antitumor response, 37 (84%) had stable disease as their best RECIST response, which was maintained for more than 6 months in 32, for a clinical benefit rate (CR+PR+SD=6mos) of 73%. In 7 of these SD pts (16%), a degree of objective tumor shrinkage was reported. Centralized radiological review is underway, focusing on non-dimensional, “tissue” response, and results thereof will be presented. In 39 pts who were symptomatic at baseline, subjective improvement of symptoms was claimed by 25 (64%). On ITT analysis, median PFS was 32 wks, with 38% of pts free from progression at one year, and 16% on treatment at 18 months. Most frequent drug-related adverse events were nausea (35%) and vomiting (30%), edema (30%), skin rash (28%), G1–3 anemia (24%), asthenia (17%), G1–3 leucopenia (13%). Conclusions: Preliminary evidence of Imatinib efficacy in chordoma was provided in a single-institution, compassionate setting, and is now confirmed by this multicenter Phase II study. On the basis of these data, an international effort on molecular-targeted therapy with Imatinib in advanced chordoma is warranted.

No significant financial relationships to disclose.