Randomized phase II selection trial of FLASH and conventional radiotherapy for patients with localized cutaneous squamous cell carcinoma or basal cell carcinoma: A study protocol.

Background: Cutaneous basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most prevalent skin cancers in western countries. Surgery is the standard of care for these cancers and conventional external radiotherapy (CONV-RT) with conventional dose rate (0.03-0.06 Gy/sec) represents a good alternative when the patients or tumors are not amenable to surgery but routinely generates skin side effects. Low energy electron FLASH radiotherapy (FLASH-RT) is a new form of radiotherapy exploiting the biological advantage of the FLASH effect, which consists in delivering radiation dose in milliseconds instead of minutes in CONV-RT. In pre-clinical studies, when compared to CONV-RT, FLASH-RT induced a robust, reproducible and remarkable sparing of the normal healthy tissues, while the efficacy on tumors was preserved. In this context, we aim to prospectively evaluate FLASH-RT versus CONV-RT with regards to toxicity and oncological outcome in localized cutaneous BCC and SCC. Methods: This is a randomized selection, non-comparative, phase II study of curative FLASH-RT versus CONV-RT in patients with T1-T2 N0 M0 cutaneous BCC and SCC. Patients will be randomly allocated to low energy electron FLASH-RT (dose rate: 220-270 Gy/s) or to CONV-RT arm. Small lesions (T1) will receive a single dose of 22 Gy and large lesions (T2) will receive 30 Gy in 5 fractions of 6 Gy over two weeks.The primary endpoint evaluates safety at 6 weeks after RT through grade ≥ 3 toxicity and efficacy through local control rate at 12 months. Approximately 60 patients in total will be randomized, considering on average 1-2 lesions and a maximum of 3 lesions per patients corresponding to the total of 96 lesions required. FLASH-RT will be performed using the Mobetron® (IntraOp, USA) with high dose rate functionality.LANCE (NCT05724875) is the first randomized trial evaluating FLASH-RT and CONV-RT in a curative setting.

Impact of gender on patients hospitalized for SARS-COV-2 infection: A prospective observational study.

Biological sex could affect the natural history of severe acute respiratory syndrome coronavirus 2 infection. We enrolled all COVID-19 patients admitted to two COVID-19 hospitals in Milan in a prospective observational study. The primary outcome was death during the study period and the secondary outcome was critical disease at hospital admission. The association(s) between clinically relevant, noncollinear variables, and the primary outcome was assessed with uni- and multivariable Logistic regression models. A total of 520 patients were hospitalized of whom 349 (67%) were males with a median age 61 (interquartile range: 50-72). A higher proportion of males presented critically ill when compared to females (30.1% vs. 18.7%, p < .046). Death occurred in 86 (24.6%) males and 27 (15.8%) females (p = .024). In multivariable analysis age (per 10 years more) (adjusted odds ratio [AOR]: 1.83 [95% confidence interval {CI}: 1.42-2.35], p < .0001), obesity (AOR: 2.17 [95% CI: 1.10-4.31], p = .026), critical disease at hospital admission (AOR 6.34 [95% CI: 3.50-11.48], p < .0001) were independently associated to higher odds of death whereas gender was not. In conclusion, a higher proportion of males presented critically ill at hospital admission. Age, critical disease at hospital admission, obesity, anemia, D-dimer, estimated glomerular filtration rate, lactate dehydrogenase, and creatine kinase predicted death in hospitalized COVID-19 patients.

Oligorecurrent Nodal Prostate Cancer: Long-term Results of an Elective Nodal Irradiation Approach.

OBJECTIVES: The objective of this study was to report long-term results of elective nodal radiotherapy (ENRT) in prostate cancer (PCa) patients with oligorecurrent nodal disease after primary treatment. METHODS: Data of 53 oligorecurrent PCa patients (N1 and/or M1a) with ≤5 nodal metastases (n=108) treated with ENRT combined with androgen deprivation therapy (ADT) between 2004 and 2016 were retrospectively reviewed. Median prostate-specific antigen (PSA) and PSA doubling time (DT) were 3.4 ng/mL and 5 months, respectively. At restaging, 45% of the patients presented single nodal metastases, mainly located in the pelvis (n=38). All patients underwent ENRT between 45 and 50.4 Gy with a boost on positive nodes (median 64.4 Gy; 54 to 69 Gy) using mainly VMAT (n=24) or IMRT (n=21) techniques. Concomitant ADT was administered to all patients for a median time of 6 months. RESULTS: After a median follow-up after ENRT of 44 months (range, 2 to 133), the 5-year biochemical disease-free and distant progression-free survival (DPFS) rates were 43% and 58%, respectively, with worse DPFS observed in patients with a PSA-doubling time <3 months (36.8% vs. 63.6%; P=0.029). Seventeen of 19 clinically relapsing patients presented lesions out of the ENRT field, and 10 were again oligometastatic. Only 2 patients presented with a CTCAE v3.0 grade ≥2 genitourinary toxicity. CONCLUSIONS: ENRT combined with short-course ADT is a safe and effective salvage modality for patients with oligorecurrent nodal PCa. Prospective randomized studies comparing focal SBRT versus ENRT are warranted to define the best treatment strategy.

Potential Role of Single Nucleotide Polymorphisms of XRCC1, XRCC3, and RAD51 in Predicting Acute Toxicity in Rectal Cancer Patients Treated With Preoperative Radiochemotherapy.

OBJECTIVES: To investigate the association between polymorphisms of DNA repair genes and xenobiotic with acute adverse effects in locally advanced rectal cancer patients treated with neoadjuvant radiochemotherapy. METHODS: Sixty-seven patients were analyzed for the current study. Genotypes in DNA repair genes XRCC1 (G28152A), XRCC3 (A4541G), XRCC3 (C18067T), RAD51 (G315C), and GSTP1 (A313G) were determined by pyrosequencing technology. RESULTS: The observed grade ≥3 acute toxicity rates were 23.8%. Chemotherapy and radiotherapy were interrupted for 46 and 14 days, respectively, due to critical complications. Four patients were hospitalized, 6 patients had been admitted to the ER, and 5 patients received invasive procedures (2 bladder catheters, 2 blood transfusions, and 1 growth factor therapy).RAD51 correlated with acute severe gastrointestinal toxicity in heterozygosity (Aa) and homozygosity (AA) (P=0.036). Grade ≥3 abdominal/pelvis pain toxicity was higher in the Aa group (P=0.017) and in the Aa+AA group (P=0.027) compared with homozygous (aa) patients. Acute skin toxicity of any grade occurred in 55.6% of the mutated patients versus 22.8% in the wild-type group (P=0.04) for RAD51. XRCC1 correlated with skin toxicity of any grade in the Aa+AA group (P=0.03) and in the Aa group alone (P=0.044). Grade ≥3 urinary frequency/urgency was significantly higher in patients with AA (P=0.01), Aa (P=0.022), and Aa+AA (P=0.031) for XRCC3 compared with aa group. CONCLUSIONS: Our study suggested that RAD51, XRCC1, and XRCC3 polymorphisms may be predictive factors for radiation-induced acute toxicity in rectal cancer patients treated with preoperative combined therapy.

Radiation-induced malignant meningioma following proton beam therapy for a choroidal melanoma.

We report a woman with malignant meningioma diagnosed 9 years after the treatment of a choroidal melanoma with proton beam therapy. The risk of secondary cancers is a well-known adverse late effect of radiation therapy, especially with the use of advanced techniques such as intensity-modulated radiation therapy. However, this risk may be less with the use of proton beam therapy. A 79-year-old woman presented with symptoms of enophthalmos, ptosis and paralysis of the left medial rectus muscle. She had previously been successfully treated for a choroidal melanoma of the left eye with proton beam therapy (total dose: 60 cobalt gray equivalents) following local resection. MRI showed a lesion in the left cavernous sinus with extension into the orbit and a subsequent biopsy revealed a papillary meningioma. The cavernous tumor was treated with photon radiotherapy (total dose: 54Gy) which achieved an initial partial response. However, 8 months later the tumor extensively metastasized to the skull and the spine and the patient died 1 year after the treatment. The incidence of secondary malignancies after proton beam therapy is low but not negligible, therefore, it must be taken into account when planning a treatment as secondary tumors may present with a highly aggressive behaviour.

Role of salvage stereotactic body radiation therapy in post-surgical loco-regional recurrence in a selected population of non-small cell lung cancer patients.

AIM: This is a retrospective analysis of a selected series of high-risk non-small cell lung cancer (NSCLC) patients with post-surgical loco-regional relapse treated with salvage stereotactic body radiotherapy (SBRT). Outcome and toxicity profiles were assessed. PATIENTS AND METHODS: Twenty-eight patients (unfit for surgery or systemic therapy) with 30 lesions underwent salvage SBRT as an alternative therapy because of advanced age, co-morbid conditions or no response obtained from other treatments. RESULTS: Complete and partial responses were 16% and 70%, respectively. Local progression was observed in 3 patients. Regional relapse occurred in 5 patients. Distant progression occurred in 10 patients. The 2-year overall survival (OS) and disease-free survival (DFS) were 57.5% and 36.6%, respectively. Radiation acute pneumonitis occurred as follows: three patients developed grade 1, two patients experienced grade 2 and one patient experienced grade 3 toxicity. CONCLUSION: Stereotactic body radiotherapy could have an alternative role in isolated loco-regional relapse in patients unfit or resistant to other therapies.

Hypofractionated stereotactic radiotherapy in combination with bevacizumab or fotemustine for patients with progressive malignant gliomas.

To evaluate the efficacy of hypofractionated stereotactic radiotherapy performed as reirradiation in combination with fotemustine or bevacizumab as salvage treatment in patients with recurrent malignant glioma. Between May 2006 and December 2013, 54 patients with recurrent malignant glioma received hypofractionated stereotactic radiotherapy (HSRT, 25 Gy in 5-Gy fractions) plus either fotemustine or bevacizumab at University of Rome Sapienza, Sant'Andrea Hospital. All patients had Karnofsky performance score (KPS) ≥ 60 and were previously treated with standard chemoradiotherapy. Forty-two patients had a GBM and 12 patients had an anaplastic astrocytoma (AA). The median overall survival (OS) time and 12-month OS rates after HSRT was 11 months and 30 % for patients treated with HSRT plus bevacizumab and 8.3 months and 5 % for those treated with HSRT plus fotemustine (p = 0.01). Median PFS times were 4 and 6 months for patients treated with HSRT plus fotemustine or bevacizumab, respectively (p = 0.01). KPS > 70 (p = 0.04), AA histology, and the treatment with bevacizumab were independent favourable prognostic factors for OS. In general, both treatments were well tolerated with relatively low treatment-related toxicity. HSRT combined with bevacizumab or fotemustine may represent a feasible treatment option for patients with progressive malignant gliomas, although most of the tumors recur in a few months. Efficacy of bevacizumab or alkylating agents in combination with different radiation schedules needs to be evaluated in prospective studies.

Fractionated stereotactic radiosurgery for patients with skull base metastases from systemic cancer involving the anterior visual pathway.

BACKGROUND: To analyze the tumor control, survival outcomes, and toxicity after stereotactic radiosurgery (SRS) for skull base metastases from systemic cancer involving the anterior visual pathway. PATIENTS AND METHODS: We have analyzed 34 patients (23 females and 11 males, median age 59 years) who underwent multi-fraction SRS for a skull base metastasis compressing or in close proximity of optic nerves and chiasm. All metastases were treated with frameless LINAC-based multi-fraction SRS in 5 daily fractions of 5 Gy each. Local control, distant failure, and overall survival were estimated using the Kaplan-Meier method calculated from the time of SRS. Prognostic variables were assessed using log-rank and Cox regression analyses. RESULTS: At a median follow-up of 13 months (range, 2-36.5 months), twenty-five patients had died and 9 were alive. The 1-year and 2-year local control rates were 89% and 72%, and respective actuarial survival rates were 63% and 30%. Four patients recurred with a median time to progression of 12 months (range, 6-27 months), and 17 patients had new brain metastases at distant brain sites. The 1-year and 2-year distant failure rates were 50% and 77%, respectively. On multivariate analysis, a Karnofsky performance status (KPS) >70 and the absence of extracranial metastases were prognostic factors associated with lower distant failure rates and longer survival. After multi-fraction SRS, 15 (51%) out of 29 patients had a clinical improvement of their preexisting cranial deficits. No patients developed radiation-induced optic neuropathy during the follow-up. CONCLUSIONS: Multi-fraction SRS (5 x 5 Gy) is a safe treatment option associated with good local control and improved cranial nerve symptoms for patients with a skull base metastasis involving the anterior visual pathway.

Neoadjuvant chemoradiation with concomitant boost radiotherapy associated to capecitabine in rectal cancer patients.

PURPOSE: The primary end-points were complete pathological response and local control. Secondary end-points were survivals, anal sphincter preservation, and toxicity profile. METHODS: Patients with T3/T4 and or N+ rectal cancer (n = 65) were treated with preoperative concomitant boost radiotherapy (55 Gy/25 fractions) associated to concurrent chemotherapy with oral capecitabine. RESULTS: All patients completed the programmed treatment. The complete pathological response was achieved by 17 % of the patients. Anal sphincter preservation surgery was possible for 86 % of the patients with low rectal cancer (≤ 5 cm from the anal verge). The T-stage and N-stage downstaging were achieved by 40 and 58 % of the patients, respectively. Circumferential radial margin was involved (close/positive) in eight patients. After a median follow-up of 26 months, local and distant recurrence occurred in two and 11 patients, respectively. The 3-year overall survival and disease-free survival were 86.8 and 81 %, respectively. Non-hematological ≥ grade 3 toxicities were observed in 15 % of the patients. On univariate analysis N-downstaging and positive circumferential radial margin were significantly associated with worse overall survival (p = 0.003 and p = 0.023, respectively), disease-free survival (p = 0.001 and p = 0.036, respectively), and metastasis-free survival (MFS) (p = 0.001 and p = 0.038, respectively).On multivariate analysis, the N-downstaging were significantly associated with better overall survival (OS) (p = 0.022). CONCLUSIONS: Our data support the efficacy of preoperative treatment for rectal cancer in terms of local outcomes. Radiation treatment intensification may have a biological rationale; longer follow-up is needed.

Intermediate-risk prostate cancer patients treated with androgen deprivation therapy and a hypofractionated radiation regimen with or without image guided radiotherapy.

BACKGROUND: To evaluate the efficacy of hypofractionated radiotherapy (HyRT) with or without image guided radiotherapy (IGRT) in intermediate risk prostate cancer. METHODS: 105 patients were treated with HyRT, 43,8 Gy and 54,75 Gy were delivered to the seminal vescicles and to the prostate, respectively; 3,65 Gy/fraction three times weekly. All patients underwent 9 months hormonal therapy. Patient position was verified with daily kV cone beam CT in 69 patients (IGRT group). Acute and late toxicities were evaluated according to RTOG scale. Biochemical relapse was defined using PSA nadir + 2 ng/mL. The data were prospectively collected and retrospectively analyzed to evaluate the efficacy of IGRT. RESULTS: After a median follow-up of 31 months the actuarial 3-year bNED was 93,7%. During RT, 10.5% and 7.6% of patients developed ≥Grade 2 rectal and urinary toxicities, respectively. The cumulative incidence of ≥Grade 2 late rectal and urinary toxicities at 3 years were 6,9%, and 10,8%, respectively. The incidence of ≥Grade 2 late rectal toxicities was significant reduced in the IGRT group (1,6% vs. 14,5%, p=0,021). Two patients developed Grade 3 urethral obstruction and one patient developed grade 3 rectal bleeding. CONCLUSIONS: HyRT represents a well-tolerated treatment able to achieve a high bNED. The use of daily IGRT is beneficial for reducing the incidence of late toxicities.

Hypofractionated stereotactic radiotherapy and continuous low-dose temozolomide in patients with recurrent or progressive malignant gliomas.

To evaluate the efficacy of reirradiation and systemic chemotherapy as salvage treatment in patients with recurrent malignant glioma. Between May 2006 and December 2011, 54 patients with recurrent malignant glioma received hypofractionated stereotactic radiotherapy (HSRT) plus systemic therapy at University of Rome Sapienza, Sant' Andrea Hospital. All patients had Karnofsky performance score ≥60 and were previously treated with standard conformal RT (60 Gy) with concomitant and adjuvant temozolomide (TMZ) up to 12 cycles. Thirty-eight patients had a GBM and 16 patients had a grade 3 glioma. The median time interval between primary RT and reirradiation was 15.5 months. At the time of recurrence all patients received HSRT (30 Gy in 6-Gy fractions) plus concomitant TMZ (75 mg/m(2)/day) followed by continuous TMZ at 50 mg/m(2) everyday up to 1 year or until progression. Median overall survival after HSRT was 12.4 months, and the 12- and 24-month survival rates were 53 and 16 %, respectively. The median progression-free survival (PFS) was 6 months, and the 12- and 24-month PFS rates were 24 and 10 %, respectively. KPS >70 (P = 0.04) and grade 3 glioma were independent favourable prognostic factors for survival. In general chemoradiation regimen was well tolerated with relatively low treatment-related toxicity. HSRT plus concomitant TMZ followed by continuous dose-intense TMZ is a feasible treatment option associated with survival benefits and low risk of complications in selected patients with recurrent malignant glioma. The potential advantages of combined chemoradiation schedules in patients with recurrent malignant gliomas need to be explored in future studies.

Image guided hypofractionated 3-dimensional radiation therapy in patients with inoperable advanced stage non-small cell lung cancer.

PURPOSE: Hypofractionated radiation therapy (HypoRT) can potentially improve local control with a higher biological effect and shorter overall treatment time. Response, local control, toxicity rates, and survival rates were evaluated in patients affected by inoperable advanced stage non-small cell lung cancer (NSCLC) who received HypoRT. METHODS AND MATERIALS: Thirty patients with advanced NSCLC were enrolled; 27% had stage IIIA, 50% had stage IIIB, and 23% had stage IV disease. All patients underwent HypoRT with a prescribed total dose of 60 Gy in 20 fractions of 3 Gy each. Radiation treatment was delivered using an image guided radiation therapy technique to verify correct position. Toxicities were graded according to Radiation Therapy Oncology Group morbidity score. Survival rates were estimated using the Kaplan-Meier method. RESULTS: The median follow-up was 13 months (range, 4-56 months). All patients completed radiation therapy and received the total dose of 60 Gy to the primary tumor and positive lymph nodes. The overall response rate after radiation therapy was 83% (3 patients with complete response and 22 patients with partial response). The 2-year overall survival and progression-free survival rates were 38.1% and 36%, respectively. Locoregional recurrence/persistence occurred in 11 (37%) patients. Distant metastasis occurred in 17 (57%) patients. Acute toxicities occurred consisting of grade 1 to 2 hematological toxicity in 5 patients (17%) and grade 3 in 1 patient; grade 1 to 2 esophagitis in 12 patients (40%) and grade 3 in 1 patient; and grade 1 to 2 pneumonitis in 6 patients (20%) and grade 3 in 2 patients (7%). Thirty-three percent of patients developed grade 1 to 2 late toxicities. Only 3 patients developed grade 3 late adverse effects: esophagitis in 1 patient and pneumonitis in 2 patients. CONCLUSIONS: Hypofractionated curative radiation therapy is a feasible and well-tolerated treatment for patients with locally advanced NSCLC. Randomized studies are needed to compare HypoRT to conventional treatment.

A case report of metastatic atypical thymic carcinoid with ectopic ACTH production: locoregional control after adaptive radiation treatment.

Thymic carcinoid is an extremely rare malignancy. This tumor is often associated with endocrine disorders such as Cushing's syndrome, multiple endocrine neoplasia type 1 and superior vena cava syndrome. We describe the case of a 44-year-old Italian woman with metastatic atypical thymic carcinoid secreting ectopic adrenocorticotropic hormone who was treated with adaptive radiation therapy with a curative dose schedule for a symptomatic mediastinal tumor. After 22 months, the patient was in good clinical condition, presenting stable disease without any evidence of local or systemic progression. To our knowledge there are no previously reported data regarding radical radiotherapy in the treatment of thymic carcinoids.

Fractal analysis reveals reduced complexity of retinal vessels in CADASIL.

The Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) affects mainly small cerebral arteries and leads to disability and dementia. The relationship between clinical expression of the disease and progression of the microvessel pathology is, however, uncertain as we lack tools for imaging brain vessels in vivo. Ophthalmoscopy is regarded as a window into the cerebral microcirculation. In this study we carried out an ophthalmoscopic examination in subjects with CADASIL. Specifically, we performed fractal analysis of digital retinal photographs. Data are expressed as mean fractal dimension (mean-D), a parameter that reflects complexity of the retinal vessel branching. Ten subjects with genetically confirmed diagnosis of CADASIL and 10 sex and age-matched control subjects were enrolled. Fractal analysis of retinal digital images was performed by means of a computer-based program, and the data expressed as mean-D. Brain MRI lesion volume in FLAIR and T1-weighted images was assessed using MIPAV software. Paired t-test was used to disclose differences in mean-D between CADASIL and control groups. Spearman rank analysis was performed to evaluate potential associations between mean-D values and both disease duration and disease severity, the latter expressed as brain MRI lesion volumes, in the subjects with CADASIL. The results showed that mean-D value of patients (1.42±0.05; mean±SD) was lower than control (1.50±0.04; p = 0.002). Mean-D did not correlate with disease duration nor with MRI lesion volumes of the subjects with CADASIL. The findings suggest that fractal analysis is a sensitive tool to assess changes of retinal vessel branching, likely reflecting early brain microvessel alterations, in CADASIL patients.

Assessment of metabolic response to radioimmunotherapy with 90Y-ibritumomab tiuxetan in patients with relapsed or refractory B-cell non-Hodgkin lymphoma.

PURPOSE: To prospectively compare the assessment of metabolic response to yttrium 90 ((90)Y)-ibritumomab tiuxetan radioimmunotherapy (RIT) by using fluorine 18 ((18)F) fluorodeoxyglucose (FDG) combined positron emission tomographic-computed tomographic (PET/CT) imaging at 2 and 6 months to determine the most appropriate time to detect therapeutic response in refractory non-Hodgkin lymphoma (NHL) patients treated with RIT. MATERIALS AND METHODS: The ethical committee of the university approved the protocol and all patients signed informed consent. Twenty-three consecutive patients (10 women, 13 men; mean age, 51.8 years +/-7.3 [standard deviation]) treated by using RIT for relapsed or refractory follicular NHL were enrolled. For all patients, (18)F FDG PET/CT scanning was performed at baseline and at 2 and 6 months after RIT. Response was assessed by using the International Workshop Criteria (IWC) and revised criteria (IWC + PET) as well as the criteria of the European Organization for Research and Treatment of Cancer. One-way analysis of variance for repeated measures, receiver operator curve analysis, and Kaplan-Meier curves were used for statistical analysis. RESULTS: PET/CT performed at 2 months revealed complete (n = 12) or partial (n = 4) metabolic response in 16 of 23 patients with complete or partial clinical response. These findings were all confirmed at 6-month scanning. PET/CT indicated refractory or persistent disease at 2 and 6 months in the remaining seven patients. Better overall survival was observed for patients with a reduction in the maximum standard uptake value of 49% or higher (both at 2 and 6 months after RIT) when compared with those with a decrease of less than 49% (P < .05). CONCLUSION: Early assessment of response to RIT by using PET/CT might be useful in the identification of patients needing additional therapeutic strategies.

Dual-time-point 18F-FDG PET/CT versus dynamic breast MRI of suspicious breast lesions.

OBJECTIVE: The purpose of our study was to compare dual-time-point (18)F-FDG PET/CT, performed with the patient in the prone position, and contrast-enhanced MRI in patients with suspected breast malignancy. SUBJECTS AND METHODS: Forty-four patients with 55 breast lesions underwent two PET/CT scans (dual-time-point imaging) in the prone position and breast MRI. Sensitivity, specificity, and overall accuracy were calculated. In addition, the average percentage of change in standard uptake values (Delta%SUV(max)) between time point 1 and time point 2 was calculated for PET/CT. A final histopathologic diagnosis was available for all patients. RESULTS: MRI showed an overall accuracy of 95%, with sensitivity and specificity of 98% and 80%. Conversely, dual-time-point PET/CT showed an accuracy of 84% for lesions with an SUV(max) > or = 2.5 or with a positive Delta%SUV(max), with sensitivity and specificity of 80% and 100% versus 69% accuracy, 62% sensitivity (both, p < 0.001), and 100% specificity (p not significant) for single-time-point PET/CT. On PET/CT, malignant lesions showed an increase in FDG between time points 1 and 2, with a Delta%SUV(max) of 11 +/- 24. Benign lesions showed either no change or a decrease in SUV(max) between time points 1 and 2, with a Delta%SUV(max) of -21 +/- 7. CONCLUSION: A dual time point improves PET/CT accuracy in patients with a suspected breast malignancy over single-time-point PET/CT. On PET/CT, FDG is increasingly taken up over time in breast tumors; conversely, benign lesions show a decrease in FDG uptake over time. These changes in SUV might represent a reliable parameter that can be used to differentiate benign from malignant lesions of the breast on PET/CT examination.

PET/CT colonography in patients with colorectal polyps: a feasibility study.

PURPOSE: To examine: (1) the feasibility of PET/CT colonography (PET/CTc) in patients with colorectal polyps; (2) the impact of metabolic information on CTc interpretation and, conversely, the impact of morphological information on PET characterisation of focal colorectal uptake. METHODS: Ten patients with colorectal polyps underwent PET/CTc, followed within 3 h by therapeutic conventional colonoscopy (CC). A radiologist and a nuclear medicine physician analysed the PET/CTc images. The agreement of morphological and metabolic information in the colon and rectum was evaluated. The sensitivity and specificity of PET, CT and PET/CT were calculated for colorectal polyps. RESULTS: Seventeen polypoid lesions were identified at CC: six< or =5 mm, six between 6 and 9 mm, and five > or =10 mm (four hyperplastic polyps, 11 tubular adenomas, one adenocarcinoma and one submucosal lipoma). A total of 20 scans (supine and prone) were performed in the ten patients: the agreement of morphological and metabolic information was excellent in 17 scans, good in two and moderate in one. PET/CTc showed a sensitivity of 91% for lesions > or =6 mm and a specificity of 100%. The metabolic information did not disclose any further polyps missed on CTc. The morphological information permitted correct classification of all eight instances of focal radiotracer uptake. CONCLUSION: PET/CTc is a feasible study. Adding a colonographic protocol to PET/CT images seems to allow correct characterisation of all cases of colorectal focal radiotracer uptake. The metabolic information does not seem to increase the accuracy of CTc.