Luca Guerra

Crizotinib in Advanced, Chemoresistant Anaplastic Lymphoma Kinase–Positive Lymphoma Patients

Anaplastic lymphoma kinase (ALK)-positive lymphomas respond to chemotherapy, but relapses, which bear a poor prognosis, occur. Crizotinib inhibits ALK in vitro and in vivo and was administered as monotherapy to 11 ALK+ lymphoma patients who were resistant/refractory to cytotoxic therapy. The overall response rate was 10 of 11 (90.9%; 95% confidence interval [CI] = 58.7% to 99.8%). Disease status at the latest follow-up is as follows: four patients are in complete response (CR) (months >21, >30, >35, >40) under continuous crizotinib administration; 4 patients had progression of disease (months 1, 2, 2, 2); 1 patient obtained CR on crizotinib, received an allogeneic bone marrow transplant, and is in CR; 2 patients (treated before and/or after allogeneic bone marrow transplant) obtained and are still in CR but they have stopped crizotinib. Overall and progression-free survival rates at 2 years are 72.7% (95% CI = 39.1% to 94.0%) and 63.7% (95% CI = 30.8% to 89.1%), respectively. ALK mutations conferring resistance to crizotinib in vitro could be identified in relapsed patients. Crizotinib exerted a potent antitumor activity with durable responses in advanced, heavily pretreated ALK+ lymphoma patients, with a benign safety profile.

Lung Regional Metabolic Activity and Gas Volume Changes Induced by Tidal Ventilation in Patients with Acute Lung Injury

RATIONALE During acute lung injury (ALI), mechanical ventilation can aggravate inflammation by promoting alveolar distension and cyclic recruitment-derecruitment. As an estimate of the intensity of inflammation, metabolic activity can be measured by positron emission tomography imaging of [(18)F]fluoro-2-deoxy-D-glucose. OBJECTIVES To assess the relationship between gas volume changes induced by tidal ventilation and pulmonary metabolic activity in patients with ALI. METHODS In 13 mechanically ventilated patients with ALI and relatively high positive end-expiratory pressure, we performed a positron emission tomography scan of the chest and three computed tomography scans: at mean airway pressure, end-expiration, and end-inspiration. Metabolic activity was measured from the [(18)F]fluoro-2-deoxy-D-glucose uptake rate. The computed tomography scans were used to classify lung regions as derecruited throughout the respiratory cycle, undergoing recruitment-derecruitment, and normally aerated. MEASUREMENTS AND MAIN RESULTS Metabolic activity of normally aerated lung was positively correlated both with plateau pressure, showing a pronounced increase above 26 to 27 cm H(2)O, and with regional Vt normalized by end-expiratory lung gas volume. This relationship did not appear to be caused by a higher underlying parenchymal metabolic activity in patients with higher plateau pressure. Regions undergoing cyclic recruitment-derecruitment did not have higher metabolic activity than those collapsed throughout the respiratory cycle. CONCLUSIONS In patients with ALI managed with relatively high end-expiratory pressure, metabolic activity of aerated regions was associated with both plateau pressure and regional Vt normalized by end-expiratory lung gas volume, whereas no association was found between cyclic recruitment-derecruitment and increased metabolic activity.

Lungs of patients with acute respiratory distress syndrome show diffuse inflammation in normally aerated regions: A [18F]-fluoro-2-deoxy-D-glucose PET/CT study

Objective: Neutrophilic inflammation plays a key role in the pathogenesis of acute respiratory distress syndrome (ARDS) and acute lung injury (ALI). Positron emission tomography (PET) with [18F]-fluoro-2-deoxy-d-glucose (18FDG) can be used to image cellular metabolism that, during lung inflammatory processes, likely reflects neutrophils activity. The aim of this study was to assess the magnitude and regional distribution of inflammatory metabolic activity in the lungs of patients with ALI/ARDS by PET with 18FDG. Design: Prospective clinical investigation. Patients: Ten patients with ALI/ARDS; four spontaneously breathing and two mechanically ventilated subjects, without known lung disease, served as controls. Interventions: In each individual we performed an 18FDG PET/computed tomography of the thorax. Measurements and Main Results: 18FDG cellular influx rate constant (Ki) was computed for the imaged lung field and for regions of interest, grouping voxels with similar density. In all patients with ALI/ARDS, Ki was higher than in controls, also after accounting for the increased lung density. Ki values differed greatly among patients, but in all patients Ki of the normally aerated regions was much higher (2- to 24-fold) than in controls. Whereas in some patients the highest Ki values corresponded to regions with the lowest aeration, in others these regions had lower Ki than normally and mildly hypoaerated regions. Conclusion: In patients with ALI/ARDS, undergoing mechanical ventilation since days, the metabolic activity of the lungs is markedly increased across the entire lung density spectrum. The intensity of this activation and its regional distribution, however, vary widely within and between patients.

Role of the integrated FDG PET/CT in the surgical management of patients with high risk clinical early stage endometrial cancer: Detection of pelvic nodal metastases

BACKGROUND High risk clinical stage I endometrial cancer (grade 2 and deep myometrial invasion, grade 3 and serous and clear-cell carcinoma) had 10-35% of nodal involvement. Surgical staging is considered reasonable in this setting of women, although unnecessary in 70-90%. The purpose of this study was to determine prospectively the diagnostic accuracy of 18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography 18F-FDG PET/CT in the detection of nodal metastases in patients with high risk endometrial cancer. METHODS Eleven women with grade 2 and deep myometrial invasion and 26 with grade 3 endometrial cancer underwent 18F-FDG PET/CT, followed by total hysterectomy, bilateral salpingo-oophorectomy and systematic pelvic lymphadenectomy. Histopathological findings served as the reference standard. Diagnostic performance of 18F-FDG PET/CT in nodal disease detection was reported in terms of accuracy value both in a patient-based and a lesion site-based analysis. RESULTS Pelvic nodes metastases were found at histopathological analysis in 9 of the 37 patients (24.3%). Patient-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 18F-FDG PET/CT for detection of nodal disease were 77.8%, 100.0%, 100.0%, 93.1% and 94.4%, respectively. Nodal lesion site-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 18F-FDG PET/CT were 66.7%, 99.4%, 90.9%, 97.2% and 96.8%, respectively. CONCLUSION This study shows that 18F-FDG PET/CT is an accurate method for the presurgical evaluation of pelvic nodes metastases. The high negative predictive value may be useful in selecting patients who only may benefit from lymphadenectomy, minimizing operative and surgical complications.

18F-FDG PET/CT can predict nodal metastases but not recurrence in early stage uterine cervical cancer

OBJECTIVES To evaluate the role of the metabolic characteristics of cervical tumor uptake as predictors of a) lymph node (LN) metastases, b) recurrence, in the preoperative staging of early-stage cervical cancer. METHODS 89 patients with FIGO stage IB1 and IIA<4 cm cervical cancer were imaged with FDG-PET/CT before radical hysterectomy and pelvic lymphadenectomy. PET/CT images were analyzed and correlated to histological findings. Maximum and mean standardized uptake value (SUVmax, SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG) of cervical lesions were calculated by an iterative adaptive algorithm. These parameters were correlated to the presence of: a) LN metastases, b) relapse after primary treatment. RESULTS Out of the 89 patients who underwent preoperative PET/CT scan for staging purpose, 16 were negative at cervical level: they were all pN0 and without recurrence during follow-up (mean 34.1±14.5 months). In 69 patients MTV and TLG were significantly higher (p=0.0006 and p=0.03) in pN1 patients in comparison to pN0 patients, while SUV values did not show significant differences between the two groups. No significant correlations were found between SUVmax, SUVmean, MTV, TLG and the evidence of relapse (mean follow-up 29.2±15.5 months). CONCLUSIONS In early-stage cervical cancer MTV and TLG correlate with the presence of nodal metastases, but their clinical impact on patients management has to be clarified. The absence of pathological cervical uptake could be a good prognostic factor, while SUVmax, SUVmean, MTV, TLG of the cervical uptake have not been found predictors of recurrence.

Preoperative staging of cervical cancer: Is 18-FDG-PET/CT really effective in patients with early stage disease?

OBJECTIVE Nodal status is one of the most important findings in patients with early-stage cervical cancer that requires post-surgical adjuvant therapies and influences prognosis of patients. The purpose of this study was to determine the diagnostic accuracy of 18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (18F-FDG-PET/CT) in the detection of nodal metastases. METHODS From 2004 to 2010 women with Ib1-IIa <4cm cervical cancer underwent 18F-FDG-PET/CT followed by radical hysterectomy and pelvic lymphadenectomy in our institution. 18F-FDG-PET/CT images were analyzed and histopathological findings served as the reference standard. Diagnostic performance of 18F-FDG-PET/CT in nodal disease detection was reported in terms of accuracy value. A sub analysis of women with tumor diameter <2cm (group 1) or 2-4cm (group 2) was performed in order to verify the efficacy of 18F-FDG-PET/CT in each group. RESULTS One hundred fifty-nine women were enrolled. 65% had squamous histotype and 51% had grade 3 disease. Median number of nodes dissected was 29 (range 11-61). 28/159 women (18%) showed nodal metastases. Overall patient-based sensitivity, specificity, positive and negative predictive value of 18F-FDG-PET/CT for detection of nodal disease were 32.1%, 96.9%, 69.2%and 87.0% respectively. Among the 97 (61%) women included in group 1, 8 had nodal metastases (8.2%) and 2 was discovered through 18F-FDG-PET/CT (25%), while 20/62 women of the group 2 (32.3%) had nodal involvement, of which 7 (35%) was detected by 18F-FDG-PET/CT. CONCLUSIONS This study showed that 18F-FDG-PET/CT had low sensitivity and had a minimal clinical impact in the pretreatment planning of stage Ib1-IIa <4cm cervical cancer.

Tailoring systematic lymphadenectomy in high-risk clinical early stage endometrial cancer: The role of 18F-FDG PET/CT

OBJECTIVES To evaluate the role of FDG PET/CT in the preoperative N-staging of high-risk clinical stage I endometrial cancer. The correlation between the metabolic characteristics of endometrial tumor uptake as predictors of a) lymph-node (LN) metastases and b) recurrence, was also evaluated. METHODS Seventy-six high-risk (G2 with deep myometrial invasion, G3, serous/clear-cell carcinoma) clinical stage I endometrial cancer patients underwent preoperative PET/CT scan followed by total hysterectomy, bilateral salpingo-oophorectomy and lymphadenectomy. PET/CT images were analyzed and correlated to histological findings. Maximal and mean standardized uptake value (SUVmax, SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG, defined as the product between SUVmean and MTV) of endometrial lesions were calculated and correlated to: a) presence of LN metastases, b) recurrences. RESULTS PET/CT resulted positive at LNs in 12/76 patients: 11/12 truly positive, 1/12 falsely positive. Conversely PET/CT was negative in 64/76 patients: 61/64 truly negative and 3/64 falsely negative. On pt-based analysis, sensitivity, specificity, accuracy, positive and negative predictive value of PET/CT in detecting LN metastases were 78.6%, 98.4%, 94.7%, 91.7%, 95.3%, respectively. A significant association was found between the presence of LN metastases and SUVmax (p=0.038), MTV (p=0.007), TLG (p=0.003) of the primary tumor. No correlations were found between the metabolic parameters and relapse (median follow-up 25.4months). CONCLUSIONS In high-risk clinical stage I endometrial cancer FDG PET/CT demonstrated moderate sensitivity, high specificity and accuracy for the nodal status assessment. SUVmax, MTV and TLG of the primary tumor are significantly correlated to LN metastases, while none of these parameters is predictor of recurrence.

Performance measurements for the PET/CT Discovery-600 using NEMA NU 2-2007 standards.

PURPOSE The aim of this study was to assess the performance measurements of the new PET/CT system Discovery-600 (D-600, GEMS, Milwaukee, WI). METHODS Performance measures were obtained with the National Electrical Manufacturers Association (NEMA) NU 2-2007 procedures. RESULTS The transverse (axial) spatial resolution FWHMs were 4.9 (5.6) mm and 5.6 (6.4) mm at 1 and 10 cm off axis, respectively. The sensitivity (average at 0 and 10 cm) was 9.6 cps/kBq. The scatter fraction was 36.6% (low energy threshold: 425 keV). The NEC peak rate (k=1) was 75.2 kcps at 12.9 kBq/cc. The hot contrasts for 10, 13, 17, and 22 mm spheres were 41%, 51%, 62%, and 73% and the cold contrasts for 28 and 37 mm spheres were 68% and 72%. CONCLUSIONS The Discovery-600 has good performance for the NEMA NU 2-2007 parameters, particularly in improved sensitivity compared to the scanners of the same Discovery family, D-ST and D-STE.

Preoperative 18F-FDG PET/CT in the management of advanced epithelial ovarian cancer

OBJECTIVE The introduction of 18-FDG-PET/CT during preoperative evaluation of patients with epithelial ovarian cancer (EOC) has led to an increase of the detection of extra-abdominal metastases. However, the clinical impact of this upstage remains unclear. METHODS Patients with suspected advanced EOC underwent 18-FDG-PET/CT within two weeks prior to debulking surgery. RESULTS Between 2006 and 2011 95 patients met the inclusion criteria. Based on the concordance or the discrepancy of clinical and PET/CT stage, patients were divided into 3 groups (A: clinical and PET III; B: clinical III and PET IV; C: clinical and PET IV). Twenty-five patients were upstaged from FIGO stage III to stage IV by PET/CT. The proportion of patients who achieved a residual tumor <1cm in group B and C was similar, whereas it was significantly lower compared to group A. Similarly, complete response to adjuvant chemotherapy was achieved more frequently in patients in group A. PFS was similar in the three groups (17, 17 and 12 months in group A, B and C), as well as OS (51, 41 and 35 months). CONCLUSIONS PET/CT is able to detect distant metastases in EOC patients. The presence of extra-abdominal disease probably indicates a more aggressive disease which also shows a lower response to standard chemotherapy. However, upstaged patients have a similar prognosis compared to stage III patients, probably because intra-abdominal disease is more likely to lead patients to death. This might also explain why residual tumor is the most important prognostic factor for advanced EOC patients.

Staging of High-Risk Endometrial Cancer With PET/CT and Sentinel Lymph Node Mapping

Purpose The aim of this study was to evaluate the role of PET/CT and sentinel lymph node (SLN) biopsy in staging high-risk endometrial cancer patients (G2 and deep myometrial invasion, G3, serous clear cell carcinoma or carcinosarcoma) in early clinical stage. Patients and Methods From January 2006 to December 2012, high-risk early-stage endometrial cancer patients performing PET/CT scan followed by surgery (systematic pelvic ± aortic lymphadenectomy) were included. From December 2010, SLN mapping with 99mTc-albumin nanocolloid and blue dye cervical injection was included in our clinical practice and additionally performed. Histological findings were used as the reference standard. Results Ninety-three patients were included, of which 22 of 93 had both PET/CT and SLN biopsy. The median number of dissected lymph nodes (LNs) was 28. Nineteen women (20.4%) had pelvic LN metastases; 14 were correctly identified by PET/CT. Among 5 false-negative cases, 3 occurred after the introduction of SLN mapping due to detection of micrometastases by ultrastaging. On overall patient-based analysis, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of PET/CT for pelvic LN metastases were 73.7%, 98.7%, 93.6%, 93.3%, 93.6%, respectively. Conclusions PET/CT demonstrated moderate sensitivity and high specificity in detecting pelvic LN metastases; its high positive predictive value (93.3%) is useful to refer patients to appropriate debulking surgery. Sentinel LN mapping and histological ultrastaging increased the identification of metastases (incidence, 18.3%-27.3%) not detectable by PET/CT because of its spatial resolution. The combination of both modalities is promising for nodal staging purpose.