177Lu-PSMA radioligand therapy of predominant lymph node metastatic prostate cancer

¹⁷⁷Lu-PSMA radioligand therapy (LuPRLT) is mainly used for patients with metastatic castration-resistant prostate cancer who are resistant to established drugs. This study describes LuPRLT, either LuPSMA I&T or LuPSMA RLT-617, for 45 patients with predominant lymph node metastatic prostate cancer (LNM PC). Thirty-five patients had LNM and ten patients had LNM and one or two bone metastases. Before LuPRLT, the patients had prostate specific antigen (PSA) of median 18 µg/l (interquartile range (IQR): 3.3–39). LuPRLT was given with a cumulative injected ¹⁷⁷Lu activity of median 14.5 GBq (IQR: 12.2–20.4). Maximum percentage decline of PSA was median 92% (IQR: 70–99). Thirty-five patients with only LNM had a better overall survival (OS) than ten patients with LNM and one or two bone metastases. Thirty-three docetaxel-naïve patients had a longer PSMA PET/CT progression-free survival than twelve patients who were resistant to docetaxel. Twenty-two patients who received LuPRLT with a cumulative injected ¹⁷⁷Lu activity ≥ 14.8 GBq had a better PSMA PET/CT progression-free survival than 23 patients who received LuPRLT with a lower cumulative injected ¹⁷⁷Lu activity. Seventeen patients with relapse after LuPRLT who received rechallenge LuPRLT or ActPRLT had a better OS than five patients who received other forms for relapse treatment. LuPRLT gave mild and transitory adverse effects. The findings of the present study suggest that LuPRLT of patients with LNM may be effective and safe. The promising results motivate randomized phase II trials to further quantify the impact of LuPRLT as treatment of patients with LNM.

Selective intraarterial radionuclide therapy with Yttrium-90 (Y-90) microspheres for unresectable primary and metastatic liver tumors

Background

The aim of this study was to evaluate the success of selective intraarterial radionuclide therapy (SIRT) with Yttrium-90 (Y-90) microspheres in liver metastases of different tumors. We also interpreted the contribution of SIRT to survival times according to responder- non responder and hepatic- extra hepatic disease.

Methods

The clinical and follow-up data of 124 patients who were referred to our department for SIRT between June 2006 and October 2010 were evaluated retrospectively. SIRT has been applied to 78 patients who were suitable for treatment. All the patients had primary liver tumor or unresectable liver metastasis of different malignancies. The treatment was repeated at least one more time in 5 patients to the same or other lobes. Metabolic treatment response evaluated by fluorine-18 fluorodeoxyglucose (F18-FDG) positron emission tomography/computed tomography (PET/CT) in the 6^th week after treatment. F18-FDG PET/CT was repeated in per six weeks periods. The response criterion had been described as at least 20% decrease of SUV value. Also in patients with neuroendocrine tumor serial Gallium-68 (Ga-68) PET/CT was used for evaluation of response. Patients were divided into 2 groups according to their treatment response.

Results

68 patients received treatment for the right lobe, seven patients received treatment for the left lobe and 3 patients for both lobes. The mean treatment dose was estimated at 1.62 GBq. In the evaluation of treatment response; 43(55%) patients were responder (R) and 35 (45%) patients were non-responder (NR) in the sixth week F18-FDG PET/CT. Mean pretreatment SUVmax value of R group was 11.6 and NR group was 10.7. While only 11 (31%) out of 35 NR patients had H disease, 30 (69%) out of 43 R patients had H disease (p < 0.05). The mean overall survival time of R group was calculated as 25.63 ± 1.52 months and NR group's 20.45 ± 2.11 (p = 0.04). The mean overall survival time of H group was computed as 25.66 ± 1.52 months and EH group's 20.76 ± 1.97 (p = 0.09).

Conclusions

SIRT is a useful treatment method which can contribute to the lengthening of survival times in patients with primary or metastatic unresectable liver malignancies. Also F18-FDG PET/CT is seen to be a successful imaging method in evaluating treatment response for predicting survival times in this patient group.

TACE versus TARE for patients with hepatocellular carcinoma: Overall and individual patient level meta analysis

BACKGROUND

Transarterial radioembolization (TARE) is increasingly used as an alternative to transarterial chemoembolization (TACE) for the treatment of hepatocellular carcinoma (HCC). We aimed to perform an overall and individual patient data (IPD) meta-analysis of studies comparing TACE and TARE.

METHODS

We performed a systematic literature search using pre-specified keywords with the aid of an informationist for articles from inception to 3/2020. The primary endpoint was overall survival (OS), and the secondary endpoint was time to progression (TTP).

RESULTS

Seventeen studies met inclusion criteria with 2465 unique patients, with one randomized trial, 4 prospective studies and 12 retrospective studies. Barcelona Clinic Liver Cancer (BCLC) stage B (42.8%) was the most common stage followed by BCLC A (30.3%) and BCLC C (29.0%). There was no difference in OS between the two modalities (-0.55 months, 95% CI -1.95 to 3.05). In three studies with available TTP data, TARE resulted in a longer TTP than TACE (mean TTP 17.5 vs. 9.8 months; mean TTP difference 4.8 months, 95% CI 1.3-8.3 months). IPD-level meta-analysis of 311 patients from three studies showed no difference in overall OS between the two modalities including among subgroups stratified by tumor stage and liver function. Limitations of the current literature include inconsistent length of follow-up, inconsistency in response criteria, and safety reporting.

CONCLUSIONS

Current data suggest TARE provides significantly longer TTP than TACE, although the two treatments do not significantly differ in terms of OS. Given limitations of the current data, there is rationale for prospective studies comparing these modalities.

The role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in the primary staging of rectal cancer

Background

In this study we aimed to determine the need for ¹⁸F-flourodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the preoperative staging of rectal carcinoma in our large patient group according to level and location of tumor.

Method

Totally, 97 patients diagnosed with primary rectal adenocarcinoma between May 2009 and July 2011 were included in the study. Preoperative staging was performed by evaluating contrast-enhanced thoracic, abdominal, and pelvic computed tomographies. After staging by conventional methods, all patients underwent an ¹⁸F-FDG PET/CT. In all cases, the relationship between ¹⁸F-FDG uptake and gender, tumor height at the anal canal, localization in the rectal wall, plasma carcinoembryonic antigen levels, histopathological tumor type, and tumor stage were examined.

Results

While the ceCT was normal in 4 (4%) patients, it was positive for the rectum in 93 (95%), pelvic lymph nodes in 22 (22%), and distant metastases in 14 (14%) (liver (8), lung (8), bone (2), distant lymph nodes (6), and uterus (1)). Using computed tomography, disease stages were determined as stage 0, 1, 2, 3, and 4 in 4, 8, 48, 23, and 14 patients, respectively; ¹⁸F-FDG PET/CT was normal in two (2%) patients. The mean SUVmax of FDG-positive rectal tumors was calculated as 17.31 ± 9.37. Additionally, 18F-FDG uptake was seen in pelvic lymph nodes in 15 (15%) patients and in distant organs in 24 (24%) patients (liver (9), lung (12), bone (5), distant lymph nodes (11), uterus (1), and sigmoid colon (1)). According to an ¹⁸F-FDG PET/CT, 2, 7, 47, 20, and 21 patients were staged as stage 0, 1, 2, 3, and 4, respectively. In 14 patients (14.4%), the stage of the disease was either changed, and there was a need to make adjustments to the patient’s treatment strategy (n = 10), or the type of operation was changed (n = 4). In seven patients (0.7%), findings from ¹⁸F-FDG PET/CT images did not require any changes of the treatment plan.

Conclusion

F-FDG PET/CT provides new findings in addition to conventional techniques in the staging of primary rectal cancer. These findings could change the patients’ treatment strategies.

Optimizing PSMA Radioligand Therapy for Patients with Metastatic Castration-Resistant Prostate Cancer. A Systematic Review and Meta-Analysis

The aim of the review was to evaluate patient and treatment characteristics for patients with metastatic castration-resistant prostate cancer (mCRPC) treated with PSMA radioligand therapy (PRLT) associated with above-average outcome. The systematic review and meta-analysis followed recommendations by the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA). We searched for publications in PubMed, Embase, and ClinicalTrials.gov up to 31 September 2020. Thirty-six publications and four duplicates reported 2346 patients. Nearly two-thirds of the patients had bone metastases. Median overall survival (OS) was 16 months. Asymptomatic patients and patients with only lymph node metastases lived longer than symptomatic patients and patients with more extensive metastases. Patients treated with an intensified schedule of ¹⁷⁷Lu PRLT lived longer than those treated with a conventional schedule. Half of the patients obtained a PSA decline ≥ 50% and these patients lived longer than those with less PSA decline. Approximately 10% of the patients developed hematologic toxicity with anemia grade 3 as the most severe adverse effect. Characteristics for patients, cancer, restaging, and PRLT predict above average overall survival following treatment with PRLT.

Functional compared to anatomical imaging in the initial evaluation of patients with suspected coronary artery disease: An international, multi-center, randomized controlled trial (IAEA-SPECT/CTA study)

OBJECTIVE

To test the hypothesis that, in the initial evaluation of patients with suspected coronary artery disease (CAD), stress myocardial perfusion imaging (MPI) would result in less downstream testing than coronary computed tomographic angiography (CCTA).

METHODS

In this international, randomized trial, mildly symptomatic patients with an intermediate likelihood of having CAD, and asymptomatic patients at intermediate risk of cardiac events, underwent either initial stress-rest MPI or CCTA. The primary outcome was downstream noninvasive or invasive testing at 6 months. Secondary outcomes included cumulative effective radiation dose (ERD) and costs at 12 months.

RESULTS

We recruited 303 patients (151 MPI and 152 CTA) from 6 centers in 6 countries. The initial MPI was abnormal in 29% (41/143) and CCTA in 56% (79/141) of patients. Fewer patients undergoing initial stress-rest MPI had further downstream testing at 6 months (adjusted OR 0.51, 95% CI 0.28-0.91, P = 0.023). There was a small increase in the median cumulative ERD with MPI (9.6 vs. 8.8 mSv, P = 0.04), but no difference in costs between the two strategies at 12 months.

CONCLUSION

In the management of patients with suspected CAD, a strategy of initial stress MPI is substantially less likely to require further downstream testing than initial testing with CCTA.

TRIAL REGISTRATION

clinicaltrials.gov identification number NCT01368770.

The role of 18F-FDG-PET/CT in the preoperative staging and posttherapy follow up of gastric cancer: comparison with spiral CT

BACKGROUND

The aim of this study was to investigate the role of F-18 fluoro-deoxy-glucose (FDG) positron emission tomography and computed tomography (PET/CT) in the preoperative and posttherapy restaging of gastric cancer and to compare with spiral computerized tomography (CT).

METHOD

A total of 42 PET/CT scans of 36 gastric cancer patients (28M, 8F; mean age: 56.0±15) were included in the study. A retrospective analysis of the PET/CT results of the patients were compared with concurrent CT results. Confirmation was made by clinical course and serial imaging studies in the follow up. The compatibility ratios were calculated and the accuracy of the PET/CT was assessed. Agreement between PET/CT and concurrent CT was calculated using kappa statistics.

RESULTS

Patients were separated into 3 groups: the patients who were referred to our clinic for preoperative staging (4 patients), for posttherapy evaluation (24 patients) and for the suspicion of local recurrence and/or metastasis exploration after a disease free period (8 patients). Groups 1 and 3 included a small number of patients so they were omitted from the statistical analysis. Focusing on Goup 2, the overall concordance rate was 50% (12 patients). Region based analysis showed the rates of concordance for local recurrence, local lymph node metastasis and distant metastasis were 91% (Kappa: 0.70), 95% (Kappa: 0.86) and 50% (Kappa: 0.26) respectively. Distant metastases were also investigated in detail and the two techniques showed a concordance of 91% (Kappa: 0.75) for liver, 79% (Kappa:0.31) for distant lymph node, 79% (0.42) for lung, 87% (Kappa:0.33) for bone and 95% for intestinal wall metastasis.

CONCLUSION

PET/CT is a complementary imaging method which can be successfully used in both preoperative and posttherapy evaluation of gastric cancer.

Introducing FDG PET/CT-guided chemoradiotherapy for stage III NSCLC in low- and middle-income countries: preliminary results from the IAEA PERTAIN trial

Purpose

Patients with stage III non-small-cell lung cancer (NSCLC) treated with chemoradiotherapy (CRT) in low- and middle-income countries (LMIC) continue to have a poor prognosis. It is known that FDG PET/CT improves staging, treatment selection and target volume delineation (TVD), and although its use has grown rapidly, it is still not widely available in LMIC. CRT is often used as sequential treatment, but is known to be more effective when given concurrently. The aim of the PERTAIN study was to assess the impact of introducing FDG PET/CT-guided concurrent CRT, supported by training and quality control (QC), on the overall survival (OS) and progression-free survival (PFS) of patients with stage III NSCLC.

Methods

The study included patients with stage III NSCLC from nine medical centres in seven countries. A retrospective cohort was managed according to local practices between January 2010 and July 2014, which involved only optional diagnostic FDG PET/CT for staging (not for TVD), followed by sequential or concurrent CRT. A prospective cohort between August 2015 and October 2018 was treated according to the study protocol including FDG PET/CT in treatment position for staging and multimodal TVD followed by concurrent CRT by specialists trained in protocol-specific TVD and with TVD QC. Kaplan–Meier analysis was used to assess OS and PFS in the retrospective and prospective cohorts.

Results

Guidelines for FDG PET/CT image acquisition and TVD were developed and published. All specialists involved in the PERTAIN study received training between June 2014 and May 2016. The PET/CT scanners used received EARL accreditation. In November 2018 a planned interim analysis was performed including 230 patients in the retrospective cohort with a median follow-up of 14 months and 128 patients in the prospective cohort, of whom 69 had a follow-up of at least 1 year. Using the Kaplan–Meier method, OS was significantly longer in the prospective cohort than in the retrospective cohort (23 vs. 14 months, p = 0.012). In addition, median PFS was significantly longer in the prospective cohort than in the retrospective cohort (17 vs. 11 months, p = 0.012).

Conclusion

In the PERTAIN study, the preliminary results indicate that introducing FDG PET/CT-guided concurrent CRT for patients with stage III NSCLC in LMIC resulted in a significant improvement in OS and PFS. The final study results based on complete data are expected in 2020.

Electronic supplementary material

The online version of this article (10.1007/s00259-019-04421-5) contains supplementary material, which is available to authorized users.

Prognostic importance of prostatic specific antigen response in patients who received Lutetium-177 prostate-specific membrane antigen treatment for castration resistant prostate cancer

BACKGROUND

This study aims to analyze the prognostic importance of serum prostate specific antigen (PSA) response in patients who received radioligand therapy (RLT) with Lu-177 Prostate-specific membrane antigen (PSMA) for their castration-resistant prostate cancer.

METHODS

Thirty consecutive patients who received Lu-177 PSMA treatment for their castration-resistant prostate carcinoma were included. All the patients had undergone Ga-68 PSMA PET/CT scanning before Lu-177 PSMA therapy, which revealed multiple metastases. Patients were treated with a fixed dose (180 mCi) of Lu-177 PSMA at six to eight weeks intervals. PSA response was evaluated using Prostate Cancer Working Group 3 (PCWG3) criteria. Serum PSA response was classified as PSA progression (25% increase over the baseline and an increase in the absolute-value PSA level by at least 5 ng per millilitre), any <50% decline or ≥50% decline. PSA response was evaluated six weeks after every cycle. Response evaluation with radiological imaging and Ga-68 PSMA PET/CT were performed before the first cycle and eight weeks after the last cycle.

RESULTS

Thirty patients were treated with a total of 171 cycles (median 4, range 3-7) of Lu-177 PSMA. A decline in serum PSA of ≥50% was detected in ten patients (33%) while a decline in PSA of any amount was observed in fifteen (50%) patients after the first cycle. After the last cycle, a decline in PSA ≥50% and of any amount was seen in thirteen (43%) and fourteen (46%) patients, respectively. Of the fifteen patients who were not responder after the first cycle, three (20%) had a decline in PSA of any amount after the completion of the RLT. Moreover, of the 20 patients who did not have a ≥50% decline in PSA level after the first cycle, four (20%) became responder after the last cycle. Regarding serum PSA response after the first cycle, median OS was significantly higher for patients who had ≥50% decline in PSA level with 21.0±10.0 (95% CI: 1.2-40.7) months compared to patients who had not with 8.0±2.6 (95% CI: 2.7-13.2) months (P=0.012). A decline in PSA of any amount after the first cycle did not have a significant impact on median OS (12.0±1.1 vs. 6.0±2.5 months, P=0.08). The decline in serum PSA level after the last cycle of treatment had a significant impact on OS. Median OS for the decline in PSA of any amount was calculated as 13.0±1.0 (95% CI: 10.9-15.0) months for responders and 6.0±1.9 (95% CI: 2.2-9.7) months for non-responders (P=0.016). Considering ≥50% of decline as a response, median OS was 21.0±5.8 (95% CI: 9.5-32.4) months for responders and 6.0±3.0 (95% CI: 0.1-11.8) months for non-responders (P=0.026).

CONCLUSIONS

Serum PSA level during RLT with Lu-177 PSMA remains a clinically significant factor to predict OS times. About twenty percent of patients who were not responder after the first cycle could become responder after the last cycle. However, patients without PSA response after completion of all cycles should be closely followed-up. Non-responder patients can achieve a response with further treatments.

Serum carcinoembryonic antigen measurement, abdominal contrast-enhanced computed tomography, and fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in the detection of colorectal cancer recurrence: a correlative study

INTRODUCTION

The aim of this study was to evaluate the correlative role of fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in carcinoembryonic antigen (CEA) measurement and contrast-enhanced abdominal computed tomography (ceCT) in the detection of colorectal cancer (CRC) recurrence.

MATERIALS AND METHODS

A total of 96 patients (40 female, 56 male; mean age, 60.6 ± 12 years) with a previous diagnosis of CRC underwent 18F-FDG PET/CT on suspicion of recurrence and were evaluated retrospectively. Inclusion criteria were accepted as the presence of increased serum CEA levels or positive findings on abdominal ceCT or both. 18F-FDG PET/CT findings were compared with histopathological findings and/or clinical follow-up data as the gold standard. Patients were divided into three groups: group 1, with increased CEA levels and normal abdominal ceCT; group 2, with normal CEA levels and positive ceCT; and group 3, with increased CEA levels and positive ceCT.

RESULTS

Whereas sensitivities of CEA, ceCT, and 18F-FDG PET/CT in the three patient groups were calculated as 91, 67, and 96%, specificities were 13, 51, and 62%, respectively. There were 35, 14, and 46 patients in groups 1, 2, and 3, respectively. In separate analyses conducted on the groups, sensitivity of 18F-FDG PET/CT was computed as 100 and 100% and specificity as 88 and 80% for groups 1 and 2. In group 3, which comprised four patients with secondary malignancies, sensitivity and specificity of 18F-FDG PET/CT were 94 and 16%, respectively.

CONCLUSION

18F-FDG PET/CT has an additional role in the detection of CRC recurrence with a higher sensitivity compared with CEA and ceCT alone, and 18F-FDG PET/CT is especially more successful in patients with isolated elevated CEA levels or positive ceCT findings without accompanying CEA elevation.

Comparison of bone scintigraphy and Ga-68 prostate-specific membrane antigen positron emission tomography/computed tomography in the detection of bone metastases of prostate carcinoma

AIM

This study aims to assess the diagnostic performance of Ga-68 prostate-specific membrane antigen PET/computed tomography in the comparison of planar bone scintigraphy in the detection of bone metastases. Another purpose is to define the additional benefit of bone scintigraphy subsequent to prostate-specific membrane antigen PET/computed tomography and the role of prostate-specific membrane antigen PET/computed tomography in the treatment planning.

MATERIAL AND METHOD

Forty-six patients with a median interval of 19 (range: 3-90) days between prostate-specific membrane antigen PET/computed tomography and bone scintigraphy included in the analysis. Diagnostic performance of both modalities was calculated and compared.

RESULTS

Prostate-specific membrane antigen PET/computed tomography and bone scintigraphy were performed for initial staging in 25 (54%), for evaluation of biochemical recurrence in 11 (24%) and metastatic castration-resistant prostate carcinoma in 10 (22%) patients. In the patient-based analysis sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for bone scintigraphy for detection of bone metastases were calculated as 50%, 19-29%, 32-39%, 32-39%, and 33-39%, respectively, based on whether equivocal findings were classified as positive or negative. For prostate-specific membrane antigen PET/computed tomography, these values were found significantly higher as 100%, 95-100%, 98-100%, 96-100%, and 100%, respectively. The diagnostic performance of bone scintigraphy and PET/computed tomography in clinical subgroups was analyzed, prostate-specific membrane antigen PET/computed tomography was superior to bone scintigraphy in three groups.

CONCLUSION

In this retrospective study, prostate-specific membrane antigen PET/computed tomography was found to be superior to planar bone scintigraphy in the detection of bone metastases. Additional bone scintigraphy seems to be unnecessary in patients who underwent prostate-specific membrane antigen PET/computed tomography within three months period without additional treatment.

68Ga-PSMA PET/CT for Patients with PSA Relapse after Radical Prostatectomy or External Beam Radiotherapy

The study aimed to summarize clinical characteristics associated with Gallium-68-prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (⁶⁸Ga-PSMA PET/CT) scans as patients were restaged for prostate-specific antigen (PSA) relapse after radical prostatectomy (RP) or external beam radiotherapy (EBRT). Our analyses included multiple cox regression analyses. The study evaluated 95 patients with rising values of PSAs after RP and after EBRT. Sixty 63% of patients had a positive ⁶⁸Ga-PSMA PET/CT scan. Twelve patients (13%) had a positive site in the prostate bed, 29 patients (30%) had a positive site in the regional lymph nodes, and 19 (20%) had positive sites in distant organs. After four years follow-up, 21 patients (22%) died. Using multiple Cox regression analyses, the number of positive sites on the ⁶⁸Ga-PSMA PET/CT scan significantly predicted overall survival (OS) (p = 0.0001), whereas risk score and regional locations of the positive sites were not significant in the multiple Cox regression analyses. Our study indicates that the specific findings of ⁶⁸Ga-PSMA PET/CT scans are important because detailed findings of the scans predict the outcome after salvage treatment of patients with PSA relapse examined with ⁶⁸Ga-PSMA PET/CT scans.

Intra-pancreatic Accessory Spleen Mimicking Pancreatic Neuroendocrine Tumor on 68-Ga-Dotatate PET/CT

Neuroendocrine tumors (NETs) are rare tumors, but the incidence is increasing with new diagnostics. A 37-year-old man was admitted to our hospital for an incidental 17-mm nodule in the tail of the pancreas. PET/CT shows indeterminate mass in the pancreatic tail with enhanced uptake of 68-Ga-dotatate. NET was suspected and laparoscopic distal pancreatectomy was performed. Pathologic examination revealed an accessory spleen with a heterotopic location. To the best of our knowledge, this is the first intrapancreatic accessory spleen (IPAS) case in which the positive 68-Ga-dotatate uptake reported in the literature. Our case showed that IPAS is one of the reasons of false positive involvement of 68-Ga-dotatate PET/CT. When PET/CT shows an indeterminate mass in the pancreatic tail with enhanced uptake of 68-Ga-dotatate, surgeons should keep IPAS in their mind for differential diagnosis to avoid false treatment.

Prognostic Factors for Effectiveness Outcomes After Transarterial Radioembolization in Metastatic Colorectal Cancer: Results From the Multicentre Observational Study CIRT

BACKGROUND

Transarterial radioembolisation (TARE) with Yttrium-90 resin microspheres is a treatment option for patients with metastatic colorectal cancer in the liver (mCRC). A better understanding of the prognostic factors and treatment application can improve survival outcomes.

METHODS

We analysed the safety and effectiveness of 237 mCRC patients included in the prospective observational study CIRSE Registry for SIR-Spheres Therapy (CIRT) for independent prognostic factors for overall survival (OS), progression-free survival (PFS) and hepatic progression-free survival (hPFS) using the Cox proportional-hazard model.

RESULTS

The median OS was 9.8 months, median PFS was 3.4 months and median hPFS was 4.2 months. Independent prognostic factors for an improved overall survival were the absence of extra-hepatic disease (P= .0391), prior locoregional procedures (P= .0037), an Aspartate transaminase to Platelet Ratio Index (APRI) value of ≤0.40 (P< .0001) and International Normalized Ratio (INR) ≤1 (P= .0078). Partition model dosimetry resulted in improved OS outcomes compared to the body surface area model (P = .0120). Independent predictors for PFS were APRI >0.40 (P = .0416) and prior ablation (P = .0323), and for hPFS these were 2 to 5 tumor nodules (P = .0148), Albumin-bilirubin (ALBI) grade 3 (P = .0075) and APRI >0.40 (P = .0207). During the study, 95 of 237 (40.1%) patients experienced 197 adverse events, with 28 of 237 (11.8%) patients having a grade 3 or higher adverse events.

CONCLUSION

Including easy-to-acquire laboratory markers INR, APRI, ALBI and using partition model dosimetry can identify mCRC patients that may benefit from TARE.

Prognostic Importance of Bone Marrow Uptake on Baseline 18F-FDG Positron Emission Tomography in Diffuse Large B Cell Lymphoma

AIM

To define the role of ¹⁸F-flourodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) in the detection of bone marrow (BM) involvement in patients with diffuse large B cell lymphoma (DLBCL).

MATERIALS AND METHODS

Fifty-four (mean age: 55.5 ± 18.3 years, 20 female and 34 male) DLBCL patients who underwent pretreatment ¹⁸F-FDG PET/CT were included to the study. Focal or diffuse BM ¹⁸F-FDG uptake that is higher than mediastinal blood pool uptake was accepted as positive. After staging of disease by CT and ¹⁸F-FDG PET/CT, all the patients received R-CHOP treatment after diagnostic blinded bone marrow biopsy (BMB). Presence of positive BM uptake in ¹⁸F-FDG PET/CT and histopathological examination results of BMBs were analyzed by Chi-square test. Sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of ¹⁸F-FDG PET/CT in the detection of BM involvement were calculated. Prognostic importance of the presence of BM ¹⁸F-FDG uptake was analyzed by Kaplan-Meier analysis.

RESULTS

BM ¹⁸F-FDG uptake was detected in 8 patients. Histopathological examination of BMB revealed BM involvement in 6 out of 8 patients. BMB was negative in all patients who have no ¹⁸F-FDG uptake in the evaluation of PET/CT images. Sensitivity, specificity, accuracy, PPV, and NPV of ¹⁸F-FDG PET/CT in the detection of BM involvement were calculated as 100%, 96%, 96%, 75%, and 100%, respectively. In the Kaplan-Meier analysis, we found that presence of pretreatment ¹⁸F-FDG uptake in BM has a prognostic importance. Whereas mean time to progression (TTP) in patients with BM uptake was 32.25 ± 10.9 months and mean TTP in those without was 51.69 ± 3.6 months (p = 0.013).

CONCLUSIONS

BM uptake in pretreatment ¹⁸F-FDG PET/CT is an important prognostic factor in DLBCL patients. Moreover, in consideration of high NPV, ¹⁸F-FDG PET/CT could eliminate unnecessary BMB in FDG-negative patients.

Prognostic value of metabolic parameters on baseline 18F-FDG PET/CT in small cell lung cancer

BACKGROUND

Maximum standardized uptake value (SUV<inf>max</inf>) is the primary quantitave parameter given in 18F-FDG PET/CT reports. Calculations derived from three dimensional metabolic volumetric images have been proposed to be more successful than SUV<inf>max</inf> alone in prognostification with a lower interobserver variability in many cancers. We aimed to determine the prognostic value of metabolic parameters derived from 18F-FDG PET/CT studies in small cell lung cancer (SCLC) patient population with a long follow-up time.

METHODS

In this study, 38 consecutive SCLC patients (34M, 4F, age:65.76 ±8.18 years) who were referred to 18F-FDG PET/CT for staging between October 2006-January 2011 were included. SUV<inf>max</inf>, SUV<inf>mean</inf>, SUV<inf>peak</inf>, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were calculated. Overall survival (OS) was calculated from the date of the initial PET/CT to death from any cause. Survival tables were obtained and Kaplan Meier curves were reconstructed. Mantel-Cox regression analysis was performed in order to investigate if any of these parameters have an effect on survival along with other clinical risk factors.

RESULTS

Median SUV<inf>max</inf>, SUV<inf>mean</inf>, SUV<inf>peak</inf>, MTV, TLG and LDH values were calculated as 13.9 g/dL, 6.4 g/dL,10.69 g/dL, 147 cm³, 1898.52 and 375U/L respectively. Median follow-up was 761.23±873.21 days (25.37 months, range:110-3338 days). Since basal 18F-FDG PET/CT scans, all patients were lost in the follow-up except for two patients. MTV was a significant prognostic factor in SCLC patients. Estimated mean survival times were 261.0±45.6 (95% CI: 171.6-350.3) days in patients with MTV value above the calculated median 147, and 577.0±124.0 (95% CI: 333.7-820.2) days in patients with MTV<147. The difference was statistically significant with a P=0.037.

CONCLUSIONS

Baseline whole body MTV reflecting total tumor load is a prognostic index in SCLC. SUV is insufficient to predict prognosis.

Predictor of 68Ga PSMA PET/CT positivity in patients with prostate cancer

BACKGROUND

The aim of this study was to evaluate predictive factors of 68Gallium (68Ga) prostate-specific membrane antigen (PSMA) positron emission tomography (PET)/computed tomography (CT) positivity.

METHODS

Relationships between serum prostate specific antigen (PSA), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) levels, Gleason Score (GS) and positivity of 68Ga PSMA PET in patients who underwent 68Ga PSMA PET/CT for restaging for PCa were evaluated retrospectively.

RESULTS

One hundred and four (median age: 67; range: 51-88) patients were included in this study. Of these patients, PSMA PET was positive in 75 (72%) patients. Mean serum PSA levels for PET negative and positive groups were 0.76±1.00 and 180.85±324.93 ng/mL (P<0.001). The sensitivity and specificity of 68Ga PSMA PET/CT for detection of disease recurrence were calculated as 92% and 80%, respectively, for the 1.4 ng/mL PSA cut-off and 92% and 90%, respectively, for the 2 ng/mL PSA cut-off values. The positivity rates for patients with PSA levels <1.4 ng/mL and ≥1.4 ng/mL were 21% and 90%, respectively (P<0.001).

CONCLUSIONS

68Ga PSMA PET/CT seems to be a highly sensitive in patients with early PSA recurrence. Patients with higher GS and early PSA recurrence could benefit from 68Ga PSMA PET/CT.

Volumetric analysis of the cranial and nasal cavity from micro-computed tomography scans in the rabbit

BACKGROUND

The aim of the study was to estimate the volume values of the cranial cavity and nasal cavity structures and to compare the efficiency of manual segmentation of three-dimensional reconstruction and Cavalieri's principle (CP) methodologies.

MATERIALS AND METHODS

Volume values of the cranial cavity, maxillary sinus (MS), dorsal conchal sinus (DCS), dorsal nasal meatus (DNM), middle nasal meatus (MNM), ventral nasal meatus (VNM), ventral nasal concha (VNC), middle nasal concha (MNC) and nasal vestibule (NV) were estimated with manual segmentation and CP from micro-computed tomography images in 5 male New Zealand white rabbits. Volume measurements and elapsed time were compared with each other. Three-dimensional reconstruction models of nasal and cranial cavity structures were created.

RESULTS

There was a statistically significant difference between methods of the MS, DCS, DNM, MNM, VNM, VNC, and MNC volume measurements. Additionally, there was a statistically significant difference between the volumetric analysis time period of the methods and CP was found much shorter than manual segmentation.

CONCLUSIONS

Realistic results were achieved in a short time with the CP among the stereology methods. It is thought that these image and quantitative data results can be used for modelling, toxicology and pathology studies such as acute and chronić rhinitis or rhino sinusitis as well as a good understanding of the relationship of the anatomical structures in the nasal cavity.

Prognostic Importance of the Presence of Early Metabolic Response and Absence of Extrahepatic Metastasis After Selective Internal Radiation Therapy in Colorectal Cancer Liver Metastasis

AIMS

In this study, the authors aimed to identify prognostic factors after selective internal radiation therapy (SIRT) for colorectal cancer (CRC) liver metastasis.

METHODS

Forty-nine (28 male, 21 female; mean age: 64.6 ± 10.8) patients who received SIRT for CRC liver metastasis were studied. Effects of number (<5 vs. ≥5), maximum dimension, and standardized uptake value (SUV) of liver metastases, liver tumor load (<25% vs. 26%-50% vs. 51%-75%), presence of extrahepatic disease, and metabolic early response on overall survival were analyzed.

RESULTS

Mean follow-up time was 44.1 ± 27.5 months. Overall survival time was calculated as 10.03 ± 1.61 (95% CI; 6.86-13.20) months. SUV (0.004) of liver metastases, early metabolic response (p = 0.015), and presence of extrahepatic metastasis (p = 0.001) were identified as significant factors influencing overall survival. The hazard ratio was 1:2.3 for the presence of extrahepatic metastasis and 1:2.7 for the absence of early metabolic response.

CONCLUSION

These findings suggest that patients with CRC liver metastasis who have lower SUV at presentation and early metabolic response have better outcomes after SIRT.

A Risk Model for Patients with PSA-Only Recurrence (Biochemical Recurrence) Based on PSA and PSMA PET/CT: An Individual Patient Data Meta-Analysis

An individual patient meta-analysis followed 1216 patients with PSA-only recurrence (biochemical recurrence, BCR) restaged with [68Ga]Ga-PSMA-11 PET/CT before the salvage treatment for median 3.5 years and analyzed the overall survival (OS). A new risk model included a good risk group with a prescan PSA < 0.5 ng/mL (26%), an intermediate risk group with a prescan PSA > 0.5 ng/mL and a PSMA PET/CT with 1 to 5 positive sites (65%), and a poor risk group with a prescan PSA > 0.5 ng/mL and a PSA PET/CT with > 5 positive sites (9%) (p < 0.0001, log rank test). The poor risk group had a five-year OS > 60%. Adding a BCR risk score by the European Association of Urology did not significantly improve the prediction of OS (p = 0.64). In conclusion, the restaging PSMA PET/CT markedly predicted the 5-year OS. The new risk model for patients with PSA-only relapse requires a restaging PSMA PET/CT for patients with a prescan PSA > 0.5 ng/mL and has a potential use in new trials aiming to improve the outcome for patients with PSA-only recurrence who have polysites prostate cancer detected on PSMA PET/CT.