Clinical Utility of Prostatic Specific Antigen and Prostatic Acid Phosphatase Serum Levels in Monitoring Prostate Cancer

We analysed 696 prostatic specific antigen (PSA) and prostatic acid phosphatase (PAP) serum samples by double antibody radioimmunoassay (RIA) I125 in the follow-up of 122 patients with prostate cancer under treatment. PSA levels were significantly correlated to response to treatment, whereas PAP results did not differentiate patients with partial or complete remission. Progression of the disease was detected in 95.2 and 85.4% of PSA and PAP samples, and increased to 99.9% using both simultaneously. On the whole, PSA was better than PAP in monitoring prostate cancer, and the efficacy was greater using both markers together.

Clinical Significance of Preoperative Serum Levels of CA 125 and TAG-72 in Ovarian Carcinoma

In a prospective study we evaluated in 48 patients with primary ovarian carcinoma the prognostic value of the preoperative circulating serum levels of CA 125 and TAG-72. Serum levels of CA 125 were above the cutoff level of 35 U/ml in 68% of patients, TAG-72 levels were higher than 6 U/ml in 50% of patients, while the simultaneous use of the two markers increased the sensitivity to 75%. Pretreatment CA 125 and TAG-72 levels were significantly lower (p < 0.05, for both) in patients with well differentiated tumors than in those with moderate or poor differentiation. Similarly, both marker levels were significantly higher (p < 0.001) in patients with residual disease after cytoreductive surgery than in those with no residual tumor. In addition, the CA 125 levels were also higher in initial stages (I-II) than in more advanced stages (III-IV) (p < 0.05), whereas TAG-72 levels were higher (p < 0.05) in patients with mucinous or endometrioid tumors than in those with serous carcinomas. The results further indicated that high preoperative serum levels of CA 125 and TAG-72 were associated with a shorter overall survival (p < 0.001 and p < 0.01, respectively). Finally, separate Cox multivariate analysis showed that preoperative CA 125 and TAG-72 serum levels were, after stage, the strongest factors to predict overall survival (p < 0.0001, p < 0.05 and p < 0.005, respectively) in patients with ovarian carcinoma.

Circulating Ca 15.3 Levels in Breast Cancer. Our Present Experience

CA 15.3 is an antigen expressed by human breast carcinoma cells, and defined by two monoclonal antibodies, 115D8 and DF3. We used IRMA to determine the circulating serum levels of CA 15.3 in 1178 subjects with breast cancer, non-breast malignancies, benign diseases and controls. A threshold level of 40 U/ml was established with 140 healthy controls and 650 patients with benign diseases (respectively 0% subjects and 1.5% patients had abnormal antigen levels). Elevated CA 15.3 was found in 12 of 184 patients with malignancies different from breast cancer (6.5%), either epithelial carcinomas with distant metastases, mainly in the liver, or primary liver tumors. Breast cancer patients (n=204) were analysed by prior therapy, UICC stage and WHO response to therapy. Eight of 134 (5.9%) patients with stage II or III breast cancer at presentation and no evidence of disease (NED) had elevated CA 15.3. All of 22 patients with stage IV breast cancer not responding to therapy (SD and PD) had antigen levels > 40 U/ml, as did 10 of 34 (29.4%) stage IV patients in objective response (CR+PR). Three of 14 pretreatment patients had abnormal marker levels, and they later proved to have distant metastases. Serum CA 15.3 values were statistically different (p < 0.01) in NED (20.6 ± 11.2 U/ml), CR+PR (33.5 ± 24.0 U/ml), stable disease (98.8 ± 50.4 U/ml) and progressive disease (> 200 U/ml) breast cancer patients. Our results suggest that circulating CA 15.3 antigen levels agree with the stage of breast cancer and with the response to therapy.

Preoperative CEA and TAG-72 Serum Levels as Prognostic Indicators in Resectable Gastric Carcinoma

We evaluated in 74 patients with resectable primary gastric carcinoma, the prognostic value of the preoperative circulating serum levels of CEA and TAG-72. Serum levels of CEA were above the cutoff level of 6 ng/ml in 18.9% of patients; TAG-72 levels were higher than 6 U/ml in 31% of patients. Pretreatment mean CEA levels were significantly lower (p<0.01) in patients with stage I tumors (2.9 ± 0.3 ng/ml) than in those with more advanced tumors (stage II: 14.5 ± 6.8 ng/ml; stage HI-TV: 6.8 ± 1.5 ng/ml). Similarly, significant differences in mean TAG-72 serum levels were found between stage I (3.5 ± 1.8 U/ml) and stage II and stage III-IV (30.4 ± 20.7 U/ml and 26.1 ± 9.7 U/ml, respectively) (p<0.05). In addition, TAG-72 levels were also higher in poorly differentiated and moderately differentiated tumors (38.5 ± 20.1 U/ml and 23.1 ± 9.4 U/ml, respectively) than in well differentiated tumors (4.4 ± 0.9 U/ml) (p<0.05). The results further indicated that high preoperative serum levels of CEA predicted shorter relapse-free survival duration (p<0.01), and that high TAG-72 levels were associated with shorter relapse-free and overall survival (p < 0.0001 and p < 0.0005, respectively). In addition, separate Cox multivariate analysis showed that preoperative TAG-72 was, after stage, the strongest factor to predict both relapse-free and overall survival (p < 0.0001 and p < 0.005, respectively) in patients with gastric cancer.

Evaluation of Specific Antigen and Prostatic Acid Phosphatase Specificity. Study of False Values

We assayed prostatic specific antigen (PSA) and prostatic acid phosphatase (PAP) serum levels in 1305 subjects without malignant prostatic pathology by double antibody RIA I125 to evaluate their specifity. When we set a second upper normal limit of 10 ng/ml for PSA and 2.5 ng/ml for PAP there was a significant increase of specificity. There were 2 and 3.7% false positive results in non-prostatic benign pathologies, 1.8 and 7.9% in non-prostatic malignant, 3.5 and 4.7% in non-complicated benign prostatic hypertrophy (BPH) and 3.3% for both in chronic prostatitis. In patients with complicated BPH and acute prostatitis the results were 64.8 and 24% for PSA and 20 and 16% for PAP. In conclusion, PSA is more specific than PAP in patients without acute inflammatory pathology of the prostate; the high rate of false positive values in the latter excludes its usefulness in these patients as diagnostic tumoral markers.

Simultaneous Plasma Determination of CEA, HCG-Beta and Beta-2-Microglobulin in Patients with Nontrophoblastic Tumors

With the object of studying the possible usefulness of the simultaneous plasma determination of CEA, HCG-beta and beta 2-microglobulin in patients with nontrophoblastic tumors, we measured by radioimmonoassay the concentrations of these substances in 77 patients with normal renal function. In the group without metastases (32 cases), the percentages of positivities were low and similar for the 3 tumor markers. In the group with metastases (45 cases), the χ2 test of independence between each of the 2 markers at a level of 95 % showed a relationship between the results obtained in the determination of HCG-beta and beta 2-microglobulin, as well as an independence between CEA and HCG-beta results and CEA and beta 2-microglobulin results. These data suggest the utility of determining CEA with only 1 of the other 2 antigens in disseminated tumors.

Histological Grade in Breast Cancer: Association with Clinical and Biological Features in a Series of 229 Patients

In order to study the association of histological grade (HG) with specific clinical and biological parameters which may influence the clinical behavior of infiltrating ductal carcinomas of the breast (IDC), we analyzed in 229 tissue samples the cytosolic concentrations of estrogen receptor (ER), progesterone receptor (PR), pS2, cathepsin D, hyaluronic acid (HA) and tissue-type plasminogen activator (t-PA), as well as those of the erbB2 oncoprotein, epidermal growth factor receptor (EGFR), HA, CD44v5 and CD44v6 in the cell membrane fraction. Likewise, we considered size, ploidy, S-phase fraction and axillary node involvement as variables of the study. The transition from HG1 to HG2 and from HG2 to HG3 was accompanied by a number of common features: global increase in size, greater number of tumors >2.0 cm, decrease in membrane hyaluronic acid concentrations, increased cell proliferation (S-phase >7%) and greater aneuploidy. Other events observed during the transition from HG2 to HG3 were a decrease in ER, PR, t-PA and cytosolic hyaluronic acid. These results led us to consider that HG is associated with certain clinical-biological changes that may help explain its value as a prognostic factor in breast carcinomas.

Serum Prolactin Levels in Women with Gross Cystic Breast Disease

Serum prolactin (PRL) concentrations at baseline and after TRH stimulation were determined in 15 healthy women and in 51 premenopausal patients suffering from Gross Cystic Breast Disease. All women were in the luteal phase of the menstrual cycle and patients were divided into three groups according to cyst type at presentation. Basal hormone levels were within the normal range in the control group and in the three cystic breast disease groups. The maximum PRL response to TRH stimulation was significantly higher (p < 0.001) in patients with type I cysts (low Na+/K+ intracystic ratio and apocrine epithelium) than in patients with type II cysts (high Na+/K+ intracystic ratio and flattened epithelium), type III cysts (intermediate Na+/K+ intracystic ratio and mixed epithelium) and in normal women. Serum PRL concentrations corresponding to samples obtained 60 and 90 minutes after stimulation remained higher in the first group of patients. These results led us to consider the existence of an altered central regulation of PRL secretion in patients with type I cysts at presentation.

Evaluation of the Behavior of Carcinoembryonic Antigen in Cirrhotic Patients

Benign liver diseases are a cause of increased serum levels of CEA. We studied the behavior of CEA in 86 patients with liver cirrhosis who underwent extensive clinical and laboratory evaluation. We found abnormal CEA levels in 38.4% of the patients (28.6% Child's grade A, 40.6% Child's B, and 42.4% Child's C) with a mean of 4.75 ng/ml. Significant differences were found between patients and controls. There was a trend towards higher levels of CEA in more severe cirrhosis according to Child's classification, although this was not significant. We found significant correlations between CEA and some liver tests, including glycocholic acid (r = 0.264., p = 0.012), a marker of severity in liver diseases. The increase of CEA in these patients is probably due to alterations in its metabolic processing caused by hepatocellular dysfunction. Moderate elevations of serum CEA can be expected in cirrhotic patients independently of malignancy.

Preoperative Carbohydrate Antigen 195 (CA195) and CEA Serum Levels as Prognostic Factors in Patients with Colorectal Cancer

We evaluated in 214 patients with primary colorectal cancer the prognostic value of the preoperative serum levels of CEA and CA195. For CEA these levels were above the cutoff of 6 ng/ml in 31.3% of patients, whereas for CA195 they were higher than 12 U/ml in 35.9% of patients. The simultaneous use of both antigens increased the sensitivity to 49%, which was significantly higher than that of CEA (p<0.001) and CA195 (p<0.01) taken singly. The mean preoperative CEA levels were significantly (p<0.001) correlated with Dukes’ stage only, while there was a significant correlation between preoperative serum levels of CA195 and Dukes’ stage (p<0.001), grade of differentiation (p<0.01) and tumor location (p<0.05).

The results indicated that high preoperative serum levels of CEA and CA195 were associated with a shorter overall survival (p<0.0001). In addition, separate Cox multivariate analysis showed that preoperative CA195 was, after Dukes’ stage, the strongest factor to predict overall survival (p<0.0001).

Preliminary Study of Alpha-Fetoprotein in Nonmalignant Liver Diseases. A Clinico-Biochemical Evaluation

This preliminary study was carried out to evaluate the behavior of AFP in 155 patients with benign diffuse liver diseases who underwent thorough clinical and laboratory evaluation. We found correlations between AFP and some clinical and biochemical parameters characteristic of liver diseases; serum glutamic oxalacetic transaminase (GOT) proved the most relevant (r = 0.27 p = 0.0004) and most reliable marker to predict AFP levels. 22.6% of the patients as a whole, 25.6% of the 86 cirrhotics and 18.8% of the 69 non-cirrhotics, had increased levels of AFP. Patients with active liver disease as measured by increased GOT, had higher AFP levels than patients with quiescent liver diseases (p = 0.0048), suggesting that cytolysis and/or regeneration plays a role in the increase in AFP. Elevation of the cutoff level was necessary to improve the specificity of AFP as a tumor marker. In our series, the cutoff of 9 ng/ml was exceeded by only 10% of the patients.

CA 15.3 in Nonmalignant Liver Diseases

CA 15.3 is a recent tumor marker for a wide range of cancers that is usually used for monitoring breast carcinoma patients. This study was performed to evaluate CA 15.3 behaviour in 161 patients with benign diffuse hepatic diseases who underwent thorough clinical and biochemical evaluation. Abnormal serum levels of this antigen were found in 8.7% of the 161 patients, 11.6% of the 86 cirrhotics, and 5.3% of the 75 noncirrhotic patients. The correlation between CA 15.3 and certain parameters characteristic of liver diseases was checked. IgA showed the most relevant correlation (r = 0.39, p < 0.00001) and in our series a normal level of IgA was practically determinant of normal CA 15.3 levels. Our results also support the role played by hepatocellular dysfunction in increasing levels of this antigen in spite of the low number of false-positive results. CA 15.3 can be used as a tumor marker in these patients at levels used for healthy subjects.

Cytosolic Levels of Neuron-Specific Enolase in Squamous Cell Carcinomas of the Lung

To study the behavior and possible correlations of neuron-specific enolase (NSE) with other clinicobiological parameters, we measured the cytosolic levels of this marker by means of an immunoradiometric assay (IRMA) in 95 squamous cell lung carcinoma samples. We also analyzed the levels of pS2, tissue-type plasminogen activator (t-PA), hyaluronic acid (HA), free beta subunit of human chorionic gonadotropin (β-HCG), CYFRA 21.1 and CA 125 in cytosol. On the cell surface we analyzed the concentrations of epidermal growth factor receptor (EGFR), HA, erbB-2 oncoprotein, CD44s, CD44v5 and CD44v6. Other parameters considered were clinical stage, lymph node involvement, histological grade (HG), ploidy and the cellular S-phase fraction measured by flow cytometry on nuclei obtained from fresh tissues.

In the 95 squamous cell carcinomas the cytosolic levels of NSE varied from 4.5 to 2235 ng/mg protein (median: 267) and were significantly higher (p<0.001) than those observed in 38 samples of normal pulmonary tissue obtained from the same patients (range: 56–657; median: 141.5). When classifying tumors according to the different parameters analyzed, we observed that the levels of NSE were higher in aneuploid than in diploid cases (p=0.046) and in those that were HG3 than in those that were HG2 (p<0.001). Tumors with high NSE levels (>422 ng/mg protein; 75th percentile) were more likely to have high S-phase values (p=0.012) and were more frequently aneuploid (p=0.038) and HG3 (p<0.001) than those with low levels of NSE (<180 ng/mg protein; 25th percentile).

These results lead us to the following conclusions: 1) the cytosolic concentrations of NSE are significantly higher in squamous cell carcinomas than in healthy pulmonary tissue, and 2) the cytosolic concentrations of NSE are not correlated with clinical stage or nodal involvement. However, in our study higher levels of the enzyme were statistically correlated with aneuploidy, histological grade 3 and S-phase. This may explain its association with poorer outcome and progression, but also the more favorable response of tumors with elevated NSE to chemotherapy, as suggested by other groups.

Positron Emission Tomography for the Development and Characterization of Corneal Permanence of Ophthalmic Pharmaceutical Formulations

Purpose

This work is aimed at describing the utility of positron emission tomography/computed tomography (PET/CT) as a noninvasive tool for pharmacokinetic studies of biopermanence of topical ocular formulations.

Methods

The corneal biopermanence of a topical ophthalmic formulation containing gellan gum and kappa carragenan (0.82% wt/vol) labeled with 18Fluorine (18F) radiotracers (18F-FDG and 18F-NaF) was evaluated by using a dedicated small-animal PET/CT, and compared with the biopermanence of an aqueous solution labeled with the same compounds. Regions of interest (ROIs) were manually drawn on the reconstructed PET images for quantifying the radioactivity concentration in the eye. The biopermanence of the formulations was determined by measuring the radioactivity concentration at different times after topical application. Additionally, cellular and ex vivo safety assays were performed to assess the safety of the performed procedures.

Results

Differences were observed in the ocular pharmacokinetics of the two formulations. After 1.5 hours of contact, 90% of the hydrogel remained in the ocular surface, while only 69% of the control solution remained. Furthermore, it was observed that flickering had a very important role in the approach of the trial. The application of 18F-FDG in the eye was neither irritating nor cytotoxic for human corneal epithelial cells.

Conclusions

The use of small-animal PET and 18F radiotracers in ocular pharmacokinetics of ophthalmic formulations is feasible and could be a safe method for future ocular pharmacokinetic studies in humans.

Clinicopathological characteristics of infiltrating lobular breast carcinoma in elderly women: Preliminary results

This study was conducted to investigate the clinicopathological parameters in elderly women (aged >70 years) with infiltrating lobular carcinoma (ILC) of the breast and compare the results with those obtained from younger patients (aged 55-70 years). The study sample included a total of 46 women with ILCs, 10 aged >70 and 36 aged 55-70 years. The parameters analysed were tumor size, histological grade (HG), axillary lymph node involvement, distant metastasis and immunohistochemical expression of estrogen, progesterone and androgen receptors, Ki67, p53 and B cell lymphoma 2. Compared to women aged 55-70 years, ILCs in women aged >70 years were commonly of larger size (P=0.068) and were more frequently HG3 (P=0.024). There were no statistically significant differences in the other parameters analysed. Furthermore, we were unable to determine differences in cancer recurrence and mortality in the two patient subgroups during our follow-up. In conclusion, our preliminary results, based on the limited number of cases included in this study, indicate that i) ILCs in women aged >70 years tended to be larger compared to those in women aged 55-70 years and were more frequently of grade 3; and ii) there were no significant differences in terms of recurrence and mortality between the two patient subgroups during our follow-up.

Abstract P3-11-11: Dedicated breast PET (dbPET) a unique functional new tool to accurate quantify response to neoadjuvant therapy in breast cancer

Background: Breast cancer is one of the most common cancers in women. Approximately 232,670 new cases of breast cancer (14% of all new cancer cases) and 40,000 breast cancer deaths (6,8% of all cancer deaths) are expected to occur among US women in 2014. Since 1990, breast cancer death rates have dropped by 34%. Continued progress in the control of breast cancer will require sustained and increased efforts to provide high-quality screening, diagnosis, and treatment Recently, the MAMmography with Molecular Imaging (MAMMI) dedicated breast PET (dbPET) has emerged as an additional imaging tool for breast cancer diagnosis, clarification of complex lesions and therapy follow-up. This study is aimed to determine whether correlations exist between physiological images with 18FDG of pre, post-2-cycles and post Neoadjuvant Chemotherapy, with a predictive value of response.

Methods: Twenty-five patients, and three scan points: pre, 2 cycle and post Neoadjuvant Chemotherapy were included in this analysis A prone position high-resolution dedicated breast PET (MAMMI-dbPET) was performed 60 min after administration of 90-120 MBq of 18F-FDG. Maximum standardized uptake value (SUVmax) quantification, volume characterization, positioning in all three space-axes, distances to reference points (proximal breast limit, nipple areola complex) were registered.

Results: When treatment was successful, a significant difference was found between pre and post neoadyuvant chemotherapy status and the SUVmax (p &lt; 0.001) of breast tumors. Pre Neoadjuvant (mean SUVmax, 11.4) demonstrated a significantly higher SUVmax than did post 2 cycles tumors (median SUV, 4.7) (p= 0.025). No statistical significant difference was found for SUVmax of post-2 cycles vs. post lesions with a mean SUVmax of 4.7 and 3.9 (p=0.25) respectively. A statistically significant difference was found for volume measurement of pre vs. post-2 cycles vs post Neoadjuvant therapy lesions. A clear qualitative difference by three different observers has been reported among dbPET and MRI volume characterization. A 21% of volume (measurement) discrepancies was found, always with a volume over-estimation by magnetic resonance (structural vs functional imaging). An exquisite -and unexpected- millimetric correlation with post-surgical pathology at the end of neoadjuvant theraphy has been found in dbPET images.

Conclusions: dbPET MAMMI has proven to be an excellent tool for quantification, 3D spatial localization and monitoring of neoadjuvant therapy, showing, thanks to its functional nature, earlier and better precision and accuracy than conventional techniques (MRI). Post 2-cycle and Post Neodayuvant Chemotherapy breast cancer tumors consistently display lower 18FDG uptake than pre treatment tumors when treatment is successful. This data suggest that SUVmax measurements of 18FDG-dedicated breast PET can provide valuable information about therapy efficiency. Such an association might be of relevant importance to treatment continuity or adjustement.

Citation Format: Michel Herranz, Ines Dominguez, Alvaro Ruibal, Elena Brozos, Sze Yiun Teo, Carmela Rodriguez, Jasper Chaal, Maria Teresa Curiel, Juan Cueva, Beatriz Fernandez, Gabriel G Pavón, Marielle Fortier, Rafael Lopez. Dedicated breast PET (dbPET) a unique functional new tool to accurate quantify response to neoadjuvant therapy in breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-11-11.

Abstract P5-01-09: Improving specificity and refining diagnostic accuracy of MRI in breast cancer with dedicated breast PET (dbPET)

BACKGROUND.

Continued progress in the control of breast cancer will require sustained efforts to provide high-quality screening, diagnosis, and treatment to all segments of the population. MRI has the advantages of providing a 3D view of the breast with high sensitivity, using non-ionizing radiation. However, MRI has significant limitations including its moderate specificity that, in combination with high sensitivity, often leads to unnecessary biopsies. Recently, the MAMmography with Molecular Imaging (MAMMI) dedicated breast PET (dbPET) has emerged as an additional imaging tool for breast cancer diagnosis, clarification of complex lesions and therapy follow-up. It is well known that 18F-FDG-PET has high specificity by assessing metabolic activity, potentially reducing the number of false positive findings. To compare FDG-dbPET with the conventional magnetic resonance imaging (MRI) on breast lesion characterization, we analyzed sensitivity, specificity, Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of 37 cases of patients with BC using both dbPET and MRI.

METHODS.

Thirty-seven women with known or suspected breast carcinoma (41 lesions: 36 invasive carcinomas, 2 noninvasive carcinomas, 1 case of ductal hyperplasia, and 2 benign lesions) were enrolled in this study. Both a prone dbPET Mammi scan, and routine breast MRI scans were performed. A joint reading of MRI and PET scans side-by-side by a nuclear medicine physician and a radiologist was performed. Sensitivity and specificity of MRI and dbPET scans were calculated on the basis of post-surgical pathology reports. Breast MRI examinations were performed in a 1.5-T or 3-T commercial imager (Siemens Medical Solutions) with the use of a dedicated breast coil. The imaging sequence included a sagittal T1-weighted localizing sequence followed by a sagittal T2- weighted sequence. A T1-weighted 3D, fat-suppressed fast spoiled-gradient-echo sequence was then performed with an injection of 0.1 mmol per kilogram body weight of gadolinium dimeglumine (Magnevist; Schering). A prone position high-resolution dedicated breast PET was performed 60 min after administration of 90-120 MBq of 18F-FDG.

RESULTS.

A total of 41 lesions were assessed. Lesion size range was 0.2 to 7.6 cm. In lesion-by-lesion analysis, sensitivity and specificity of MRI alone were 91% and 54%, respectively; while lesion-based sensitivity of dbPET was 93% and breast-based specificity was 100%. The positive predictive value and the negative predictive value for MRI alone were 69% and 85%, respectively; and for dbPET were 100% and 89%, respectively. In a significant number of cases, dbPET helped to clarify or disprove positive findings by MRI, and in four cases helped to define new positives that had gone unnoticed at MRI,

CONCLUSION:

Dedicated breast PET scans increase the specificity of MRI. False positives, one of the most challenging aspects of MRI in breast lesions, are reduced. The results of the current study show that FDG-dbPET is more effective than MRI in detecting true breast cancer positives. Its functional information may improve the likelihood of a successful excision, reduce costs from additional procedures, and minimize discomfort and anxiety for the patient.

Citation Format: Ines Dominguez, Michel Herranz, Sze Yiun Teo, Elena Brozos, Carmela Rodriguez, Jasper Chaal, Juan Cueva, Jose Ramon Antúnez, Gabriel Gonzalez Pavón, Marielle Fortier, Rafael López, Alvaro Ruibal. Improving specificity and refining diagnostic accuracy of MRI in breast cancer with dedicated breast PET (dbPET) [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P5-01-09.

Correction for FDG PET dose extravasations: Monte Carlo validation and quantitative evaluation of patient studies

PURPOSE

Current procedure guidelines for whole body [18F]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) state that studies with visible dose extravasations should be rejected for quantification protocols. Our work is focused on the development and validation of methods for estimating extravasated doses in order to correct standard uptake value (SUV) values for this effect in clinical routine.

METHODS

One thousand three hundred sixty-seven consecutive whole body FDG-PET studies were visually inspected looking for extravasation cases. Two methods for estimating the extravasated dose were proposed and validated in different scenarios using Monte Carlo simulations. All visible extravasations were retrospectively evaluated using a manual ROI based method. In addition, the 50 patients with higher extravasated doses were also evaluated using a threshold-based method.

RESULTS

Simulation studies showed that the proposed methods for estimating extravasated doses allow us to compensate the impact of extravasations on SUV values with an error below 5%. The quantitative evaluation of patient studies revealed that paravenous injection is a relatively frequent effect (18%) with a small fraction of patients presenting considerable extravasations ranging from 1% to a maximum of 22% of the injected dose. A criterion based on the extravasated volume and maximum concentration was established in order to identify this fraction of patients that might be corrected for paravenous injection effect.

CONCLUSIONS

The authors propose the use of a manual ROI based method for estimating the effectively administered FDG dose and then correct SUV quantification in those patients fulfilling the proposed criterion.

Association between tumor size and immunohistochemical expression of Ki-67, p53 and BCL2 in a node-negative breast cancer population selected from a breast cancer screening program

BACKGROUND/AIM

Breast cancer is the most common type of cancer among women. Breast infiltrating ductal carcinoma (IDC) is the most common type of breast cancer, approximately 80% of all breast carcinomas. The aim of this study was to analyze the association of tumor size, evaluated after histopathological analysis, with different clinical and biological parameters in IDC.

MATERIALS AND METHODS

The study group included 251 women with IDC without axillary lymph node involvement, aged between 27 and 81 years. Analyzed parameters were: age, histological grade, menopausal status, menarche, pregnancy, abortion, breastfeeding, contraceptive use, hormone replacement therapy, estrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), Ki-67, p53 and BCL2.

RESULTS

Pathological tumor size was between 0.2 and 5.1 cm (1.43±0.86 cm). Tumors in 45 cases exceeded 2 cm, in eight 3 cm and only in one 5 cm. Pathological size was significantly associated with age >70 vs. <50 years (p=0.054), histological grade III vs. I (p=0.0003), positivity for Ki-67 (p=0.0003) and for p53 (p=0.0032).

CONCLUSION

Tumor size was significantly associated with age >70 years, histological grade 3 and immunohistochemically-augmented expression of Ki-67 and p53.

A novel in silico reverse-transcriptomics-based identification and blood-based validation of a panel of sub-type specific biomarkers in lung cancer

Lung cancer accounts for the highest number of cancer-related deaths worldwide. Early diagnosis significantly increases the disease-free survival rate and a large amount of effort has been expended in screening trials and the development of early molecular diagnostics. However, a gold standard diagnostic strategy is not yet available. Here, based on miRNA expression profile in lung cancer and using a novel in silico reverse-transcriptomics approach, followed by analysis of the interactome; we have identified potential transcription factor (TF) markers that would facilitate diagnosis of subtype specific lung cancer. A subset of seven TF markers has been used in a microarray screen and was then validated by blood-based qPCR using stage-II and IV non-small cell lung carcinomas (NSCLC). Our results suggest that overexpression of HMGA1, E2F6, IRF1, and TFDP1 and downregulation or no expression of SUV39H1, RBL1, and HNRPD in blood is suitable for diagnosis of lung adenocarcinoma and squamous cell carcinoma sub-types of NSCLC. Here, E2F6 was, for the first time, found to be upregulated in NSCLC blood samples. The miRNA-TF-miRNA interaction based molecular mechanisms of these seven markers in NSCLC revealed that HMGA1 and TFDP1 play vital roles in lung cancer tumorigenesis. The strategy developed in this work is applicable to any other cancer or disease and can assist in the identification of potential biomarkers.

A new seipin-associated neurodegenerative syndrome

BACKGROUND

Seipin/BSCL2 mutations can cause type 2 congenital generalised lipodystrophy (BSCL) or dominant motor neurone diseases. Type 2 BSCL is frequently associated with some degree of intellectual impairment, but not to fatal neurodegeneration. In order to unveil the aetiology and pathogenetic mechanisms of a new neurodegenerative syndrome associated with a novel BSCL2 mutation, six children, four of them showing the BSCL features, were studied.

METHODS

Mutational and splicing analyses of BSCL2 were performed. The brain of two of these children was examined postmortem. Relative expression of BSCL2 transcripts was analysed by real-time reverse transcription-polymerase chain reaction (RT-PCR) in different tissues of the index case and controls. Overexpressed mutated seipin in HeLa cells was analysed by immunofluorescence and western blotting.

RESULTS

Two patients carried a novel homozygous c.985C>T mutation, which appeared in the other four patients in compound heterozygosity. Splicing analysis showed that the c.985C>T mutation causes an aberrant splicing site leading to skipping of exon 7. Expression of exon 7-skipping transcripts was very high with respect to that of the non-skipped transcripts in all the analysed tissues of the index case. Neuropathological studies showed severe neurone loss, astrogliosis and intranuclear ubiquitin(+) aggregates in neurones from multiple cortical regions and in the caudate nucleus.

CONCLUSIONS

Our results suggest that exon 7 skipping in the BSCL2 gene due to the c.985C>T mutation is responsible for a novel early onset, fatal neurodegenerative syndrome involving cerebral cortex and basal ganglia.

Clinical and Biological Significance of Cathepsin D Levels in Breast Cancer Cytosol in Women Over 70 years

Objective

To study cytosolic cathepsin D behavior and possible relationship with other clinical and biological parameters in women affected by breast invasive ductal carcinomas and older than 70 years (range: 71–88).

Material and methods

cytosolic levels of cathepsin D were determined by an Immunoradiometric Assay (IRMA-CIS France). Clinical and biological factors analyzed were: size, axillary lymph node involvement, distant metastasis, histological grade, ploidy, S phase cell, cytosolic estrogen receptor, progesterone receptor and pS2, and concentrations of epidermal growth factor receptor (EGFR) in cell membranes.

Results

Cathepsin D concentrations ranged between 13 and 1228 pmol/mg prot.. Median value of 41 was considered as threshold of positivity. Cathepsin D positive tumors showed higher S-phase values (P = 0.046) and were most often histological grade III (P = 0.047). However, the most important finding was the existence of a positive correlation (r = 0.51786) and statistically significant (P < 0.05) between S-phase values and cathepsin D in the overall group of tumors, and those ER+, but not in ER−. We determined cathepsin D concentrations in 131 women with invasive ductal breast carcinomas, but aged between 50 and 70 years (median 61) and we did not find differences based on those values in women >70 years. In addition, we found no correlation between S-phase values and Cathepsin D, both overall and in relation with hormone dependence (ER).

Conclusions

Those results led us to the following conclusions: (1) cytosolic concentrations of cathepsin D in invasive infiltrating breast carcinomas in women over 70 are similar to those seen in women with the same type of tumor, but aged 50 to 70 years and are associated with increased cell proliferation measured by S phase, and histological grade III; (2) in women older than 70 years, cathepsin D concentrations are statistically significantly correlated with phase synthesis values in hormone-dependent tumors, but not in hormone-independent, fact not observed in infiltrating ductal breast carcinomas of women aged between 50 and 70. This could reflect a different mitogenic role of the aspartyl protease enzyme linked to hormone dependence as age function parameter.

Breast carcinomas with hyperprolactinemia at the time of diagnosis-clinico-biological association

AIM

To analyse association between preoperative hyperprolactinemia serum levels and clinical and biological features of breast tumors.

METHODS

Serum levels of prolactin were measured in 253 women with invasive breast cancer. Clinical and biological parameters analysed were age, size, lymph node involvement, distant metastasis and immunohistochemical expression of estrogen receptor, progesterone receptor, androgen receptor, bcl-2, p53 and Ki67.

RESULTS

In ductal carcinomas hyperprolactinemia were associated with high age (p = 0.017), and with bcl-2 + + + expression (p = 0.017). Furthermore, serum prolactin values were significantly higher in bcl-2 +++ cases vs negative (p = 0.029); the same happened when we considered the positivity threshold of 25 ng/mL (p = 0.015).

CONCLUSION

Is possible to detect in 6% of infiltrating ductal breast carcinomas hyperprolactinemia (>25 ng/mL), being associated only with increasing age, but not with other clinical or biological factors; and 2) the most surprising data was the association between prolactinemia (qualitative (>25 ng/mL) and quantitative) and intense bcl-2 tissue expression, which suggests that, probably, this (prolactinemia) is not a sign of worse prognosis and evolution.