Detection of internal mammary chain infiltration in breast cancer patients by [18F]FDG PET/MRI. Therapy implications

OBJECTIVE

To evaluate the detection rate and therapeutic implication of the infiltration of the internal mammary chain (IMCI) by [18F]FDG PET/MRI for staging of patients with breast cancer.

METHODS

Prospective study including 41 women with breast cancer (stage ≥ IIB) staged by [18F]FDG PET/MR. Two-phase exam: breast imaging (prone), whole-body (supine). TNM stage assessed by peer consensus with Nuclear Medicine and Radiology specialists. Study of the afferent vessel (AV) to IMC by breast MRI. IMCI was correlated with age, AV-IMC, T stage, breast quadrants, axillary and distant infiltration. Therapeutic re-evaluation by a multidisciplinary committee.

RESULTS

IMCI detection rate of 34% (14/41), with 8/14 patients under 55 years of age. All 14 patients with IMCI showed AV-IMC, 6 of them (43.9%) without VA-axillary. Of 27/41 patients without IMCI, in 13 (48.1%) only AV-axillary was found, in the remaining 14 (51.9%), AV-axillary and AV-IMC was found. In 57% (8/14) tumours were multicentric and 42% (6/14) focal, in inner quadrants in 4/6 (66.7%). In 1/14 patient (7.1%) only IMCI was found, in 9/14 (64.3%) axillary and IMC, in 4/14 patients (28.6%) distant lesions were detected. Committee re-evaluation: no further treatment in 27/41 patients (65.8%), thoracic radiotherapy in 10/41 patients (24.4%), systemic therapy in 4/41 patients (9.7%).

CONCLUSION

Our detection rate of IMCI in breast cancer staging by [18F]FDG PET/MR was 34%. Related factors were age, multicentric tumours, inner quadrants, detection of AV-IMC, NM staging. The evidence of IMCI allowed tailored therapy, with thoracic radiotherapy implementation in 24.4% of patients.

Immunoglobulins in systemic sclerosis management. A large multicenter experience

OBJECTIVE

To analyze the effectiveness and safety of intravenous immunoglobulin (IVIG) given in routine care to patients with systemic sclerosis (SSc).

METHODS

A retrospective multicenter observational study was conducted in SSc patients treated with IVIG. We collected data on epidemiological parameters and clinical outcomes. Firstly, we assessed changes in organ manifestations during IVIG treatment. Secondly, we analyzed the frequency of adverse effects. The following parameters were collected from baseline to the last follow-up: the patient's weight, modified Rodnan Skin Score (mRSS), modified manual muscle strength scale (MRC), laboratory test(creatine kinase(CK), hemoglobin and protein levels), The University of California Los Angeles Scleroderma Clinical Trials Consortium gastrointestinal tract 2.0 (UCLA GIT 2.0) questionnaire, pulmonary function tests, and echocardiography.

RESULTS

Data were collected on 78 patients (82% females; 59% with diffuse SSc). Inflammatory idiopathic myopathy was the most frequent concomitant overlap disease (41%). The time since Raynaud's phenomenon and SSc onset were 8.8 ± 18 and 6.2 ± 6.7 years respectively. The most frequent IVIG indication was myositis (38/78), followed by gastrointestinal (27/78) and cutaneous (17/78) involvement. The median number of cycles given were 5. 54, 53 and 9 patients have been treated previously with glucocorticoids, synthetic disease-modifying antirheumatic drugs and biologic therapies respectively. After IVIG use we found significant improvements in muscular involvement (MRC ≥ 3/5 92% IVIG, p = 0.001 and CK levels from 1149 ± 2026 UI to 217 ± 224 UI, p = 0.02), mRSS (15 ± 12.4 to 13 ± 12.5, p = 0.015) and improvement in total score of UCLA GIT 2.0 (p = 0.05). None Anti-RNA polymerase III patients showed an adequate response in gastrointestinal involvement (0/7) in comparison with other antibodies (0 vs. 25, p = 0,039). Cardiorespiratory involvement remained stable. A total of 12 adverse events were reported with only one withdrawn due to serious adverse effect.

CONCLUSIONS

this study suggest that IVIG may improve myositis, gastrointestinal and skin involvement in SSc patients treated in routine care and seems to have a good safety profile.

Standardization of acquisition protocols using PET/CT with 18F-Choline in prostate cancer

AIM

To standardize acquisition protocols for ¹⁸F-Choline PET/CT to prevent from urine interference, to determine the best time point for the whole-body study, and to assess whether "dual point" acquisition allows for differentiating malignant vs. benign lesions.

METHODS

One hundred consecutive patients with prostate cancer were prospectively studied. Immediately after ¹⁸F-Choline injection, a pelvis study was acquired, and a whole-body was subsequently obtained 1 and 2 hours p.i. Mean SUVmax was obtained in regions and for every sequential imaging. Mean analysis (χ²) and SUV percentage change (2/1 hours; 1 hours/0 min) were obtained. Metabolic pattern dynamics were assessed: accumulative vs. clearance. Patient follow-up after therapy and directed classification whenever ethically possible were performed.

RESULTS

Fifty-three prostate foci, without disturbing urinary activity was ever found on early images. Accumulative pattern in 42, with percentage increase was: 0 min/1 hour: +16.7% (χ²0.94); 1/2 hours: +10,0% (χ² 0.83). Clearance pattern in 11, with percentage decrease: 0 min/1 hour: -21.4% (χ²0.91): -7.7% (χ²0.85), corresponding in 7 to initial staging and in 4 post-radiotherapy biochemical recurrence. Every infradiaphragmatic uptake (n: 24) showed accumulative pattern, with percentage increase of +9.1% (χ²0.97), all of them depicted on early imaging. As for 12 supradiaphragmantic uptake, 8 of them showed clearance pattern with percentage decrease: -13.0% (χ²0.95). Accumulative pattern showed in 4 of them with percentage increase +13.0% (χ² 0.96), thus being assessed as invasive/malignant. Every bone uptake (n: 18) showed accumulative pattern, with percentage increase: +17.1% (χ²0.95), all of them depicted on 1 hour imaging.

CONCLUSIONS

As for prostate assessment is concerned, dual point at 0 min/1 hour proved to be the best procedure. As for supradiaphragmatic lymph-nodes detection, dual point with 1/2 hours performed best. As for infradiaphragmatic and bone involvement, as well as for inconclusive findings, the 2 hour imaging increased our diagnostic confidence.

Value of 18F-Choline PET/MRI hybrid technique on the therapeutic approach for patients with prostate cancer treated with prostatectomy and rising prostate specific antigen levels below 1 ng/ml

OBJECTIVE

To assess the detection rate of ¹⁸F-Choline PET/MRI and subsequent changes in therapy approach for patients with prostate cancer treated by prostatectomy and with rising levels of PSA <1 ng/ml.

METHODS

Prospective study with our first 36 patients with prostatectomy for prostate cancer and rising levels of PSA, who were referred for an ¹⁸F-Choline PET/MRI study. A dual-phase study was acquired after intravenous administration of 185±10% MBq of ¹⁸F-Choline: 1) early imaging (immediately after tracer administration) of prostate area (emission PET/Multiparametric MRI). 2) whole-body imaging 1 h after tracer injection (emission PET/MRI: T1, T2, STIR, diffusion). The therapy approach for patients was decided upon the Oncology Committee consensus based on ¹⁸F-Choline PET/MRI findings.

RESULTS

Twenty out of 36 patients (55.6%) were positive for the ¹⁸F-Choline PET/MRI study: 8 (22.2%) within the prostatectomy bed, 7 (19.4%) with infradiaphragmatic lymph nodes, 4 (11.1%) with local recurrence and infradiaphragmatic lymph nodes, and 1 (2.8%) with bone metastasis. Sixteen out of the 36 patients (44.4%) were negative for the ¹⁸F-Choline PET/MRI study. ¹⁸F-Choline PET/MRI findings had an impact on the therapy approach to follow: 15 patients (41.6%) showed oligometastatic disease which was treated by imaging-guided radiotherapy, 5 (13.9%) with multiple metastatic disease were treated by androgen deprivation therapy, 16 (44.4%) negative were under active surveillance.

CONCLUSION

Hybrid ¹⁸F-Choline PET/MRI procedure showed a high detection rate for recurrence in prostate cancer patients treated with prostatectomy and rising PSA levels <1 ng/ml, and ¹⁸F-Choline PET/MRI findings resulted in a better tailored therapy approach delivered to our patients.

Acoustic field generated by an innovative airborne power ultrasonic system with reflectors for coherent radiation

In order to obtain the maximum efficiency in industrial processes assisted by airborne power ultrasound, the ultrasonic systems must be capable of generating an acoustic field with a maximum energy concentration in the desired areas. In this paper, the acoustic performance of two different ultrasonic systems is presented. The first system corresponds to an airborne power ultrasonic transducer with a flat rectangular plate radiator, and the second system is composed by the same transducer mounted in a set of reflectors that allow the generation of coherent radiation. The acoustic pressure field for each system has been determined numerically and the spatial pattern has been experimentally measured. In the experiment, the system with reflectors obtained higher pressure amplitude in a wider area, due to the coherent radiation achieved. The directivity pattern obtained in the experiment confirms this coherent radiation field. This is the first time that the acoustical behavior of two different ultrasonic systems with flat rectangular radiator, vibrating in a complex flexural mode, has been numerically and experimentally described and compared in terms of pressure amplitude distribution and directivity pattern.

Modal analysis and nonlinear characterization of an airborne power ultrasonic transducer with rectangular plate radiator

Some industrial processes like particle agglomeration or food dehydration among others can be enhanced by the use of power ultrasonic technologies. These technologies are based on an airborne power ultrasonic transducer (APUT) constituted by a pre-stressed Langevin-type transducer, a mechanical amplifier and an extensive plate radiator. In order to produce the desired effects in industrial processing, the transducer has to vibrate in an extensional mode driving an extensive radiator in the desired flexural mode with high amplitude displacements. Due to the generation of these high amplitude displacements in the radiator surfaces, non-linear effects like frequency shifts, hysteresis or modal interactions, among others, may be produced in the transducer behavior. When any nonlinear effect appears, when applying power, the stability and efficiency of this ultrasonic technology decreases, and the transducer may be damaged depending on the excitation power level and the nature of the nonlinearity. In this paper, an APUT with flat rectangular radiator is presented, as the active part of an innovative system with stepped reflectors. The nonlinear behavior of the APUT has been characterized numerically and experimentally in case of the modal analysis and experimentally in the case of dynamic analysis. According to the results obtained after the experiments, no modal interactions are expected, nor do other nonlinear effects.

Assessment of the extension of pressure ulcers into soft tissue and osteomyelitis diagnosis using 18F-FDG PET/CT

The precise assessment of pressure ulcer extension in patients with neurological diseases has crucial therapeutic implications, especially in the early detection of fistula to interior structures and osteomyelitis. Two case reports are presented on patients with a similar ischial ulcer, in whom an ¹⁸F-FDG PET/CT study enabled a precise assessment of infectious complications in underlying tissues. These cases support the implementation of ¹⁸F-FDG PET/CT as a first-line technique in their management.

18F-FDG PET/CT in follow-up evaluation in pediatric patients with Langerhans histiocytosis

PURPOSE

We evaluated the impact of ¹⁸F-FDG PET/CT in identifying sites of active disease and to assess therapeutic follow up in a group of pediatric patients with Langerhans cell histiocytosis (LCH).

METHOD

During 2007-2013, 13 ¹⁸F-FDG PET/CT studies were performed for follow-up in 7 patients with a diagnosis of LCH (4 female, 3 male; 1-12 years-old). PET findings were analyzed and correlated with the CT and MRI. Findings were also follow-up by these techniques.

RESULTS

PET was negative in 4 patients (all diagnosed with bone lesions and one with pituitary involvement also). CT findings showed residual morphological bone lesions in all patients, and hypophysis MRI study showed no abnormal signal. PET remained negative at 10, 14, 25 and 28 months, and no new lesions on CT and MRI were detected. PET was positive in 3 patients (one with cervical lymphadenopathy and 2 with bone lesions, one also with pituitary involvement not identified by PET). CT findings showed pathological cervical lymphadenopathy (n=1), bone lesions (n=2) and also a pituitary MRI lesion (n=1). In a patient with cervical lymphadenopathy histology demonstrated LCH involvement. In the other 2 patients, PET remained positive with an increase of ¹⁸F-FDG bone uptake at 17 and 19 months.

CONCLUSION

In our preliminar study, ¹⁸F-FDG PET is a useful imaging procedure, along with other diagnostic tools, for identification of active lesions.

The value of 11C-methionine PET in the early differentiation between tumour recurrence and radionecrosis in patients treated for a high-grade glioma and indeterminate MRI

OBJECTIVE

To evaluate the contribution of ¹¹C-Methionine PET in the early differentiation between tumour recurrence and radionecrosis in patients treated for a high grade glioma.

METHOD

The study included 30 patients with glioma (III/IV grade) treated with surgery/radiotherapy/chemotherapy (5-8 months) and with an indeterminate MRI. All patients underwent a ¹¹C-Methione PET (within 15 days of MRI) and studies were visually analysed (intensity and morphology of uptake), quantified (SUV max/SUV mean background), and coregistered to MRI (3D-Flair). Patient management was decided by the neuro-oncology committee to clinical and imaging follow-up, second-line treatment, or surgery.

RESULTS

There were 23 ¹¹C-Methionine PET studies visually positive. Morphology of uptake was focal in 15, diffuse in 4, and ring-shaped in 4. Three out of the focal uptake cases underwent resection (Histopathology +). Sixteen underwent second-line therapy (11 responded; 5 progressed). The 4 cases with ring-shaped uptake were followed-up, and progression was found in 2 (true-positive), and disease-free in 2 (follow-up of 6 and 7 months, respectively) (false-positive). Seven out of ¹¹C-Methionine studies PET were visually negative, and all of them were disease-free (follow-up of 3-12 months). SUV lesion/background was 2.79±1.35 in tumour recurrence, and 1.53±0.39 in radionecrosis (P<.05). Taking into account a SUV lesion/background threshold of 2.35, the sensitivity and specificity values were 90.5% and 100%, respectively.

CONCLUSION

Visual analysis, quantitative and PET/MRI coregistration of ¹¹C-Methionine PET showed their complementary role in patients with indeterminate MRI results, thus allowing early differentiation between tumour recurrence and radionecrosis, and helping in the individual therapy approach.

Peritoneal Cancer Index by (18)F-FDG PET/TC pre and post-hyperthermic intraperitoneal chemotherapy. Report of a case

Radical cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy increases survival in patients with end-stage peritoneal carcinomatosis, and who are under palliative therapy. The Peritoneal Cancer Index enables the tumor burden to be quantified during surgery, as well as treatment planning and patient prognosis. It is obtained by combining the tumor spread in 13 abdominal and pelvic regions with the largest tumor size. Fluorodeoxyglucose positron emission tomography/computed tomography is the technique of choice for those patients selected to undergo radical cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy, due to its higher detection rate of carcinomatosis, and since it allows extra-peritoneal disease staging. The simplified Peritoneal Cancer Index (9 regions defined by 2 transverse and 2 sagittal planes) obtained by fluorodeoxyglucose positron emission tomography/computed tomography allows correlation with the surgical procedure, therefore its standardization is advisable.

Salvage radiotherapy in prostate cancer patients. Planning, treatment response and prognosis using (11)C-choline PET/CT

OBJECTIVE

To assess the prognostic value of the therapeutic response by (11)C-choline PET/CT in prostate cancer patients with biochemical recurrence in which (11)C-choline PET/CT indicated radio-guided radiotherapy.

METHODS

The study included 37 patients initially treated with prostatectomy, who were treated due to biochemical recurrence. (11)C-choline PE/CT detected infra-diaphragmatic lymph-node involvement. All were selected for intensity modulated radiation therapy, escalating the dose according to the PET findings. One year after treatment patients underwent PSA and (11)C-choline PET/CT categorizing response (complete/partial/progression). Clinical/biochemical/image monitoring was performed until appearance of second relapse or 36 months in disease-free patients.

RESULTS

(11)C-choline PET/CT could detect lymph nodes in all 37 patients. They were 18 (48.6%) of more than a centimetre in size and 19 (51.3%) with no pathological CT morphology: 9 (24.3%) with positive lymph nodes of around one centimetre and 10 (27.0%) only less than a centimetre in size. The response by (11)C-choline PET/CT was categorised one year after radiotherapy: 16 patients (43.2%) complete response; 15 (40.5%) partial response, and 6 (16.2%) progression. The response was concordant between the PSA result and (11)C-choline PET/CT in 32 patients (86.5%), and discordant in five (13.5%). New recurrence was detected in 12 patients (80%) with partial response, and 5 (31.2%) with complete response. The mean time to recurrence was 9 months after partial response, and 18 months after complete response (significant difference, p<.0001).

CONCLUSION

(11)C-choline PET/CT allows the selection of patients with recurrent prostate cancer candidates for radiotherapy and to plan the technique. The evaluation of therapeutic response by (11)C-choline PET/CT has prognostic significance.

Diagnosis by (18)F-FDG PET/CT of infective endocarditis, staging and monitoring of antibiotic treatment after transposition of surgically corrected great arteries

Infective endocarditis is one of the leading causes of fever of unknown origin in those patients with intravascular catheters, prosthetic valves or cardiovascular implantable electronic devices. The diagnosis of infective endocarditis is made according to modified Duke criteria, which are based on blood culture and echocardiographic findings. Demonstration of vegetation with the transoesophageal echocardiography may be difficult in these cases with previous anatomical changes, especially in early phases. Positron emission tomography with (18)F-fluorodeoxyglucose ((18)F-FDG PET/CT) is well known to show an increased glucidic metabolism in malignant, inflammatory, and infectious processes. Thus, it provides useful functional imaging that enables the disease causing the fever of unknown origin to be detected well before structural changes are evident. Moreover, (18)F-FDG PET/CT helps to detect infectious extra-cardiac involvement, since the whole body is imaged with this technique. (18)F-FDG PET/CT may have an additional promising role for the monitoring of response to antimicrobial therapy in patients with established infective endocarditis, thus evaluating standard treatment outcome, as well as evaluating the need for alternative/intensified treatment options.

11C-Choline PET/CT in the primary diagnosis of prostate cancer: impact on treatment planning

AIM

Aim of the present study was to evaluate the usefulness of 11C-choline PET/CT for detecting lymphatic or haematogenous spread and for planning radiotherapy in patients with medium-to-high risk prostate cancer.

METHODS

We have included 61 consecutive patients recently diagnosed with cancer prostate by biopsy. All patients were classified as medium-to-high risk: Gleason: 7-9; PSA: 6.3-30.4 ng/mL; stage T2c (N.=20) or stage T3 (N.=41). Image acquisition began 5 min after intravenous injection of 11C-choline (656+119 MBq), starting at the pelvis and continuing craniocaudally. Images were interpreted visually to evaluate uptake by the prostate gland. Lymph nodes with 11C-choline uptake were considered invaded, regardless of their size. Bone lesions were considered positive when they showed greater focal uptake than the surrounding bone. In patients with evidence of lymph-node invasion or bone metastases (15 patients), disease was classified as locoregional, oligometastatic, or multimetastatic.

RESULTS

All patients had prostate gland uptake (20 focal, 8 bifocal, and 33 multifocal). Extraprostatic disease was present in 15 patients (24.6%), as follows: 9 (60%) in a single location: in an infradiaphragmatic lymph node (N.=6), in a supradiaphragmatic lymph node (N.=1), and in bone (M1) (N.=2). Six (40%) as multifocal invasion: with both infra- and supradiaphragmatic lymph node involvement (N.=2); with infradiaphragmatic lymph node involvement and M1 bone metastases (N.=3); and infra- and supradiaphragmatic lymph node involvement plus M1 bone metastases (N.=1). Disease was classified as locoregional (N.=6), oligometastatic (N.=5), and multimetastatic (N.=4). The 11 (73.3%) patients with locoregional and oligometastatic disease were selected to undergo intensity-modulated radiation therapy with dose escalation based on the PET findings.

CONCLUSION

Our results suggest that 11C-choline PET/CT is a useful one-stop diagnostic procedure for evaluating patients with medium/high risk prostate cancer scheduled for radical treatment. 11C-choline PET/CT can reliably rule out lymph node involvement and remote metastases, allowing to select candidates for radiotherapy and to plan their treatment.