Genome wide association study of genes controlling resistance to Didymella rabiei Pathotype IV through genotyping by sequencing in chickpeas (Cicer arietinum).

Ascochyta blight (AB) is a major disease in chickpeas (Cicer arietinum L.) that can cause a yield loss of up to 100%. Chickpea germplasm collections at the center of origin offer great potential to discover novel sources of resistance to pests and diseases. Herein, 189 Cicer arietinum samples were genotyped via genotyping by sequencing. This chickpea collection was phenotyped for resistance to an aggressive Turkish Didymella rabiei Pathotype IV isolate. Genome-wide association studies based on different models revealed 19 single nucleotide polymorphism (SNP) associations on chromosomes 1, 2, 3, 4, 7, and 8. Although eight of these SNPs have been previously reported, to the best of our knowledge, the remaining ten were associated with AB resistance for the first time. The regions identified in this study can be addressed in future studies to reveal the genetic mechanism underlying AB resistance and can also be utilized in chickpea breeding programs to improve AB resistance in new chickpea varieties.

First report of Ascochyta rabiei infections on endemic Turkish populations of Cicer bijugum and C. turcicum.

Ascochyta rabiei causes Ascochyta blight disease on C. arietinum as well as on annual C. reticulatum, C. pinnatifidum and C. judaicum and perennial C. montbretii, C. isauricum, C. ervoides species (Can et al. 2007; Frenkel et al. 2007; Ozkilinc et al. 2019; Peever et al. 2007; Tekin et al. 2018). During field survey studies carried out on annual Cicer spp. in June 2022, concentric ring-shaped lesions were observed on the stems and leaves of C. bijugum in Mardin province and C. turcicum in Elazig province. Cicer reticulatum and C. arietinum plants were also found in the location where C. bijugum was found. No disease symptoms were observed in other Cicer species, while C. bijugum had 32% disease incidence. The disease incidence among the C. turcicum population was 37.3 %, and no chickpea cultivation area was found near it. Diseased plant parts were surface sterilized, placed on ½ potato dextrose agar (PDA) and incubated at 24±2 oC in 12 hours light/dark photoperiod. Each symptomatic plant was considered as one isolate. Monosporic isolates were obtained and the same colony morphology developed from all plant parts of C. turcicum and C. bijugum. Spores were oblong and spore sizes were 10.73±0.62 µm (n=15) in length and 3.60±0.25 (n=15) µm in width, 10.64±0.98 (n=15) µm in length and 3.00±0.26 (n=15) µm in width for isolates obtained from C. turcicum and C. bijugum, respectively. Amplicons for all 40 isolates were generated with mating type (MAT) primers, and the ITS region was amplified and sequenced by using the ITS4 and ITS5 primers (Peever et al. 2007). For the MAT primers, a 700 bp amplicon was observed for all the 20 isolates obtained from C. bijugum conferring to MAT1.1 idiomorph. In contrast, for the isolates obtained from C. turcicum 14 isolates had a 700 bp amplicon for MAT1.1 and 6 isolates had a 500 bp amplicon for MAT1.2, thus representing both idiomorphs in a ~2:1 ratio. BLAST analysis of the ITS sequences showed 100% homology with the reference ITS sequences for A. rabiei except for 23 SVRC CT 09/22 and 23 SVRC CT 22/22 isolates showing 99.81 % similarity. All sequences were submitted to GenBank (OP967923, OP967924, OP967925, OP967926 and OP967927 for A. rabiei isolates from C. turcicum; OP981072, OP981073 and OP981074 for A. rabiei isolates from C. bijugum). A phylogenetic tree was constructed using MEGAX software and the Neighbor-Joining method, using the ITS sequences of A. rabiei, other Ascochyta spp. and Colletotrichum gloeosporioides. The A. rabiei isolates from C. turcicum and C. bijugum clustered together with A. rabiei sequences from the NCBI (Kumar et al. 2018). Twelve-day-old C. bijugum and C. turcicum seedlings were inoculated with 5 x 105 spore/mL concentration of spores from 5 C. turcicum and 3 C. bijugum isolates and put in plastic bags for 24 hours (Can et al. 2007). Pathogenicity tests were carried out in triplicate pots with four plants each for each isolate in a controlled climate chamber at 24±2 oC, 70% humidity under 12 hours light/dark conditions. The first symptoms were observed within 7 days after inoculation (dai) and severe Ascochyta blight symptoms developed on all plants by 21 dai. Cicer bijugum and C. turcicum are endemic Cicer species exhibiting narrow distribution in the Southeastern region of Republic of Türkiye. As a major biotic stress source, A. rabiei could be an important threat to Cicer spp (Abbo et al. 2003). To our knowledge, this is the first report of A. rabiei from C. bijugum and C. turcicum species.

Comparison of [68 Ga]Ga-DOTA-FAPI-04 PET/CT and [18F]FDG PET/CT in colorectal cancer.

AIM: In this study, we aimed to evaluate the diagnostic sensitivity of [68 Ga]Ga-DOTA-FAPI-04 PET/CT in the evaluation of primary or recurrent tumor, and nodal, peritoneal, and distant organ metastases in patients with newly diagnosed or relapsed colorectal cancer (CRC) in comparison with [18F]FDG PET/CT. MATERIALS AND METHOD: Thirty-nine patients with histopathologically confirmed primary or relapsed CRC were included in our study. All patients underwent both [18F]FDG and [68 Ga]Ga-DOTA-FAPI-04 PET/CT imaging in the same week. Primary lesions, lymph nodes, and metastatic lesions were recorded on both scans. SUVmax and background values were measured from the primary and metastatic lesions; tumor-to-background ratio (TBR) was calculated and compared. The results of the operation were compared with PET findings in patients who underwent surgical treatment without neoadjuvant chemotherapy (NAC). RESULTS: The sensitivity and specificity of [68 Ga]Ga-DOTA-FAPI-04 PET/CT in the evaluation of primary tumors were 100%, while the sensitivity of [18F]FDG PET/CT was 100% and its specificity was 85.3%. When evaluated with surgical results in the detection of lymph nodes, [68 Ga]Ga-DOTA-FAPI-04 PET/CT had a sensitivity of 90% and a specificity of 100%, whereas [18F]FDG PET/CT had a sensitivity of 80% and a specificity of 81.8%. The sensitivity and specificity of [68 Ga]Ga-DOTA-FAPI PET/CT for peritoneal implants were 100%, and the sensitivity of [18F]FDG PET/CT was 55%. The SUVmax of primary lesions was higher with [18F]FDG (p < 0.001), while TBR was higher in [68 Ga]Ga-DOTA-FAPI PET/CT than [18F]FDG PET/CT (p: 0.008). SUVmax and TBR of the lymph nodes were significantly higher in [68 Ga]Ga-DOTA-FAPI PET/CT than [18F]FDG PET/CT (p < 0.001 for both). CONCLUSION: [68 Ga]Ga-DOTA-FAPI-04 PET/CT achieved much higher sensitivity and specificity in the detection of primary lesions, and especially the lymph nodes and peritoneal metastases, suggesting that it can be employed in the assessment of primary tumor and metastases in patients with CRC in routine clinical practice.

The role of basal metabolic and volumetric 18F-FDG PET/CT parameters and their changes in predicting pathological complete response in breast cancer patients receiving neoadjuvant chemotherapy.

OBJECTIVE: The aim of this study is to investigate the roles of pre- and post- treatment quantitative fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) parameters including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) and their rate of change in predicting pathological complete response (pCR) in patients with local and locally advanced invasive breast cancer receiving neoadjuvant chemotherapy (NAC). SUBJECTS AND METHODS: Ninety-eight patients who received NAC after being diagnosed with local and locally advanced invasive breast cancer between January 2017 and September 2021 were retrospectively included in our study. Molecular subtypes of all patients were determined. Maximum SUV, MTV, TLG, percent change in SUVmax (ΔSUVmax), ΔMTV, and ΔTLG obtained from PET/CT scans performed before and after NAC were calculated. The cut-off, AUC, sensitivity, and specificity values of these parameters in predicting pCR were calculated using receiver operating characteristic (ROC) curves. RESULTS: ΔTMTV (cut-off 94.01%, AUC: 0.846), ΔTTLG (cut-off 97.36%, AUC: 0.870), B2MTV (cut-off<1.75, AUC: 0.764), B2TLG (cut-off<2.11, AUC: 0.764), B2SUVmax (cut-off<1.58, AUC: 0.767), ΔBMTV (cut-off 93.67%, AUC: 0.851), ΔBTLG (cut-off 97.22%, AUC: 0.870), ΔBSUVmax (cut-off 84.99%, AUC: 0.846) calculated using ROC curves were found to significantly predict pCR with high sensitivity and specificity. CONCLUSION: We concluded that metabolic and volumetric PET/CT parameters, the rates of their change, and metabolic response during NAC may be important variables in predicting pCR in patients with breast cancer.

Nivolumab-Related Dry Mouth and Dry Eye: Cross-Sectional Study.

To evaluate ICIs related dry eye and dry mouth in nivolumab therapy, 24 patients receiving nivolumab (group 1), 30 patients in remission without treatment for 6 months (group 2), 30 healthy participants (group 3) were cross-sectionally examined. Schirmer's 1, 2, TSH blood tests, serological analysis, salivary flow scintigraphy and minor-salivary gland biopsy were performed. Schirmer's tests were performed with anesthetic (1) and without anesthetic (2). Schirmer's scores were lower in group 1 with more frequent reduced tear production (p < 0.001). TSH levels negatively correlated with Schirmer's scores. Functional insufficiency was detected by salivary flow scintigraphy in 7 out of 10 patients with Schirmer's test positivity. In Schirmer's positive patients, lymphocytic sialadenitis was confirmed in 4 patients (focus score > 1) and CD4 T lymphocyte precipitation was observed in 6 patients. Nivolumab therapy may be associated with ICIs related immune sicca.

Diversity of rhizobial and non-rhizobial bacteria nodulating wild ancestors of grain legume crop plants.

Chickpeas, lentils, and peas are the oldest grain legume species that spread to other regions after their first domestication in Fertile Crescent, and they could reveal the rhizobial evolution in relation to the microsymbionts of wild species in this region. This study investigated the phenotypic and genotypic diversity of the nodule-forming rhizobial bacteria recovered from Pisum sativum subsp., Cicer pinnatifidum, and Lens culinaris subsp. orientalis exhibiting natural distribution in the Gaziantep province of Turkey. PCA analyses of rhizobial isolates, which were tested to be highly resistant to stress conditions, showed that especially pH and salt concentrations had an important effect on these bacteria. Phylogenetic analysis based on 16S rRNA determined that these wild species were nodulated by at least 7 groups including Rhizobium and non-Rhizobium. The largest group comprised of Rhizobium leguminosarum and Rhizobium sp. while R. pusense, which was previously determined as non-symbiotic species, was found to nodulate C. pinnatifidum and L. culinaris subsp. orientalis. In recent studies, Klebsiella sp., which is stated to be able to nodulate different species, strong evidences have been obtained in present study exhibiting that Klebsiella sp. can nodulate C. pinnatifidum and Pseudomonas sp. was able to nodulate C. pinnatifidum and P. sativum subsp. Additionally, L. culinaris subsp. orientalis unlike other plant species, was nodulated by Burkholderia sp. and Serratia sp. associated isolates. Some isolates could not be characterized at the species level since the 16S rRNA sequence similarity rate was low and the fact that they were in a separate group supported with high bootstrap values in the phylogenetic tree may indicate that these isolates could be new species. The REP-PCR fingerprinting provided results supporting the existence of new species nodulating wild ancestors.

Role of 68Ga-PSMA PET/CT parameters in treatment evaluation and survival prediction in prostate cancer patients compared with biochemical response assessment.

OBJECTIVE: In this study, we aimed to evaluate the concordance of biochemical treatment response with gallium-68-prostate specific membrane antigen (68Ga-PSMA) positron emission tomography/computed tomography (PET/CT) treatment response in prostate cancer (PCa) and investigate their prognostic effects on survival. MATERIALS AND METHODS: One hundred and fifty-onepatients with PCa, who underwent 68Ga-PSMA PET/CT imaging in our clinic between May 2016 and December 2019, were on treatment, and had pre-treatment and post-treatment imaging studies were included in our study. The treatment patients received and prostate-specific antigen (PSA) levels at the time of PET/CT imaging were recorded. Pre- and post-treatment whole-body metabolic tumor volume (MTVw), whole-body total lesion PSMA (TLPw), percent change in PSA (ΔPSA), ΔMTV, and ΔTLP values were calculated in all patients. Survival time of all patients was measured from the time of initial PET imaging. RESULTS: Median age of patients included in our study was 71 years (range: 51-88). When ΔPSA response and ΔTLP response were evaluated together (r: 0.71, P<0.001 and k: 0.541, P<0.001), statistically significance strong correlation and moderate concordance was observed. ΔPSA response and ΔMTV treatment response had statistically significant moderate correlation and moderate concordance (r: 0.66, P<0.01 and k: 0.454, P<0.001, significantly). Between ΔPSA response and ΔTLP and ΔMTV response had stronger correlation and higher concordance when PSA levels were above 10. Multivariate analyses using multiple Cox regression analysis revealed MTVw1 and ΔMTV parameters to be independent prognostic factors for mortality (P:0.003 and P:0.001, respectively). CONCLUSION: We observed that biochemical response and whole-body volumetric 68Ga-PSMA PET/CT parameter response showed correlation and concordance in all groups with PCa, which was more significant when PSA level was ≥10ng/mL. MTVw1 and ΔMTV parameters obtained via 68Ga-PSMA PET/CT were independent prognostic factors for mortality in PCa. Gallium-68-PSMA PET/CT is a valuable imaging technique for diagnostic purposes as well as follow-up and prognostic evaluation.

Associations of volumetric whole-body 18F-FDG PET/CT parameters with the CA 19-9 level and haemogram parameters in pancreatic adenocarcinoma.

OBJECTIVE: The present study compared metabolic and volumetric fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) parameters [metabolic tumour volume (MTV), total lesion glycolysis (TLG), and maximum standardized uptake value (SUVmax)] with carbohydrate antigen (CA) 19-9 tumour marker levels and haemogram parameters [(neutrophil-lymphocyte ratio, mean platelet volume (MPV), and platelet-lymphocyte ratio] as prognostic and diagnostic markers of pancreatic cancer. MATERIAL AND METHODS: A total of 66 patients who underwent 18F-FDG PET/CT in our nuclear medicine clinic between February 2017 and March 2019, and had a diagnosis of pancreatic adenocarcinoma, were included in this retrospective study. The enrolled patients had not been administered steroids or operated on. Among these patients, whose haemogram parameters and tumour markers could not be assessed by PET/CT within the same week were excluded. The MTV, TLG, and SUVmax values were calculated from primary tumours and metastases in all patients. RESULTS: Spearman's rho correlation, used to examine the relationship between the CA 19-9 level and PET parameters, revealed a statistically significant positive correlation of CA 19-9 with the whole-body MTV (MTVWB) (P<0.001) and whole-body TLG (TLGWB) (P<0.001). Although no significant relationship was found between the neutrophil count and TLGWB according to Spearman's rho correlation, in an artificial neural network using the hidden layer activation function, the neutrophil count showed the strongest association with MTVWB among all included variables. The primary pancreatic tumour MTV and TLG values showed statistically significant positive correlations with the metastases MTV, metastases TLG, MTVWB, and TLGWB values. CONCLUSION: The CA 19-9 level is considered an important marker of tumour load; it shows a statistically significant positive correlation with parameters such as MTVWB and TLGWB, which provide a measure of the whole-body tumour load. It appears that the MTV and TLG values of the primary pancreatic tumour could also be used as markers of the whole-body tumour load, given their associations with MTVWB and TLGWB.

Phenotypic and genotypic diversity of root nodule bacteria from wild Lathyrus and Vicia species in Gaziantep, Turkey.

This study identified the phenotypic and genotypic characteristics of the bacteria that nodulate wild Lathyrus and Vicia species natural distribution in the Gaziantep province of Turkey. Principle component analysis of phenotypic features revealed that rhizobial isolates were highly resistant to stress factors such as high salt, pH and temperature. They were found to be highly sensitive to the concentrations (mg/mL) of the antibiotics neomycin 10, kanamycin, and tetracycline 5, as well as the heavy metals Ni 10, and Cu 10, and 5. As a result of REP-PCR analysis, it was determined that the rhizobial isolates were quite diverse, and 5 main groups and many subgroups being found. All of the isolates nodulating wild Vicia species were found to be related to Rhizobium sp., and these isolates were found to be in Clades II, III, IV, and V of the phylogenetic tree based on 16S rRNA. The isolates that nodulated wild Lathyrus species were in Clades I, II, IV, V, VI, VII, and VIII, and they were closely related to Rhizobium leguminasorum, Rhizobium sp., Phyllobacterium sp., Serratia sp., and Pseudomonas sp. According to the genetic analyses, the isolates could not be classified at the species level, the similarity ratio was low, they formed a distinct group that was supported by strong bootstrap values in the phylogenetic tree, and the differences discovered in the network analysis revealed the diversity among the isolates and gave important findings that these isolates may be new species.

68 Ga-PSMA Versus 18 F-FDG PET/CT in the Evaluation of Epithelioid Hemangioendothelioma.

ABSTRACT: A 32-year-old man with epithelioid hemangioendothelioma was imaged with 68 Ga-PSMA PET/CT to evaluate the potential of 177 Lu-PSMA radionuclide therapy after progression findings were observed on follow-up 18 F-FDG PET/CT imaging. Liver lesions showed low FDG SUV max . The lesion-to-background ratio (TBR) was calculated as 5.1/2.9 on 18 F-FDG PET/CT imaging. However, 68 Ga-PSMA PET/CT showed moderate PSMA SUV max . TBR was calculated as 4.5/1.1. In conclusion, in this case report, we demonstrated that 68 Ga-PSMA with moderate TBR in epithelioid hemangioendothelioma may be promising for 177 Lu-PSMA radionuclide therapy.

The prognostic role of whole-body volumetric positron emission tomography/computed tomography parameters in treatment naive colorectal cancer patients with liver metastases.

PURPOSE: The present study aimed to predict the prognostic role of quantitative 18F-fluorodeoxyglucose PET/computed tomography parameters such as maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) obtained from primary tumor, lymph node metastases, and liver metastasis (LM) in patients with colorectal LM (CLM). MATERIAL AND METHOD: The research was designed as a retrospective study and 66 patients with CLM were enrolled between January 2017 and December 2018. Primary tumor SUVmax (PSUVmax), liver SUVmax (LSUVmax), and lymph node SUVmax (LnSUVmax) values obtained from the primary tumor, liver, and lymph nodes were recorded. In addition, total MTV (TMTV) and total TLG (TTLG) values were obtained by summing the values obtained from the primary tumor (PMTV and PTLG), lymph nodes (LnMTV and LnTLG), and liver (LMTV and LTLG). Univariate and multivariate Cox regression analysis was used to measure the effects of prognostic variables on mortality and survival. RESULT: In univariate Cox regression analysis, PMTV (P = 0.001), LnMTV (P = 0.008), LnTLG (P = 0.008), LnSUVmax (P = 0.047), and TTLG (P = 0.038) were identified as prognostic factors for overall survival. No statistically significant relationship was found between MTV and TLG values of LM and overall survival. In multivariate analysis, PMTV (P = 0.022) was identified as an independent prognostic factor. CONCLUSION: In conclusion, our study demonstrated that the PMTV value used in evaluating treatment-naive patients diagnosed with CLM is an independent prognostic factor for survival. Our results need to be confirmed with more studies involving more patients.

Should new organ involvement be included in Response Evaluation Criteria in PSMA Imaging?

PURPOSE: The current study is intended to investigate the effect of new organ involvement on overall survival (OS) and modify the Response Evaluation Criteria in PSMA Imaging (RECIP) by including new organ involvement to RECIP 1.0. MATERIALS AND METHODS: This retrospective study includes 114 patients diagnosed with metastatic castration-resistant prostate cancer (mCRPC) between September 2017 and June 2022 who had received docetaxel treatment and had baseline and post-treatment prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) images. The inclusion criteria were patients with pre- and post-treatment [18F]FDG PET/CT images and whose [18F]FDG PET images were negative. Those whose data were unavailable, who had additional malignancy, or who received abiraterone, enzalutamide, or Lutetium (Lu)-177 treatment were excluded. Age, Gleason score (GS), TPSA (total prostate-specific antigen) levels, surgical history, and OS information were recorded for each patient. RESULTS: The 114 patients herein had a median age of 72.5 (51-91) years and a median GS of 8 (7-10). New lesions were observed in 59 patients (51.7%) and new organ PSMA uptake was observed in 14 patients (12.2%). In the multivariate Cox regression analysis, volume-based treatment response (vTR)-total lesion PSMA (TLP), RECIP PSMA-VOL, modified RECIP (mRECIP) PSMA-VOL, and mRECIP TLP were independent prognostic factors for mortality (p < 0.001, p = 0.006, p = 0.003, and p = 0.003, respectively). The median OS of patients with new organ involvement and new lesion with PSMA uptake was 9.3 months (95% CI 2.1-16.5 months) and 11.8 months (95% CI 7.4-16.2 months), respectively. CONCLUSION: The study concluded that new organ involvement had a shorter OS than new lesion involvement. In the mRECIP that we developed, unlike RECIP, we demonstrated that both PSMA-VOL and TLP value were independent prognostic factors for mortality.

Molecular identification of LAB and yeasts from traditional sourdoughs and their impacts on the sourdough bread quality characteristics.

In this research, the LAB and yeast isolations and identifications of homemade traditional sourdoughs were investigated. Both LAB and yeasts were identified by the PCR method and used in the production of sourdough bread (SDB). Twelve types of SDB were produced from combinations of isolated LAB and yeasts. Eleven LAB and yests were identified from 36 sourdoughs. The most frequently isolated LAB species were Lactobacillus brevis (45.0%), Pediococcus acidilactici (20.0%) and Lactobacillus plantarum (18.3%) while other LAB species were isolated by only 1.7-3.5%. On the other hand, 27.5% of the isolates were Saccharomyces cerevisiae, which was followed by Pichia kudriavzevii (25.0%) and Kluyveromyces marxianus (12.5%). The total titratable acidity and pH of the sourdough ranged from 3.10 to 34.45% and from 4.05 to 4.80 respectively. High acceptable loaf height (7.2 cm), moisture (30.05%), dry matter (69.95%), volume (1370 cm3), specific volume (4.35 cm3 g -1 ) and sensory value (62 scores) were determined for SDB12. Isolated LAB is mainly composed of heterofermentative species (75%). Among the bread produced with the combination of LAB and yeasts, the SDB12 was the most preferred SDB in terms of sensory analysis and other quality characteristics. The use of homofermentative and heterofermentative LAB and yeast combinations provided high-quality SDB. This would be due to the symbiotic growth of these microorganisms. The use of L. plantarum by L. brevis and by other species resulted in high-quality SDB.

Superiority of 18 F-FDG PET/CT to 68 GA-FAPI PET/CT in Adrenocortical Tumor Imaging.

ABSTRACT: 18 F-FDG PET/CT was performed to evaluate the response to treatment in a 62-year-old female patient who was operated for adrenocortical carcinoma. High FDG uptake was observed in recurrent lesion in the left adrenal gland site and metastatic lesions. In the 68 Ga-FAPI-04 PET/CT study, low FAPI uptake was observed in both recurrences and metastases. In this case, we demonstrated the superiority of 18 F-FDG PET/CT over 68 Ga-FAPI-04 PET/CT in the evaluation of adrenocortical carcinoma.

Incidental Detection of a Type B3 Thymoma on 68Ga-FAPI-04 PET/CT Imaging.

ABSTRACT: 18F-FDG PET/CT performed for staging of colon cancer in a 60-year-old woman revealed a thymic neoplasm with increased radiopharmaceutical uptake in the anterior mediastinum. 68Ga-FAPI PET/CT showed low FAPI uptake in the anterior mediastinal mass. The patient was diagnosed with type B3 thymoma by histopathologic evaluation. In this case, thymoma demonstrated lower uptake with FAPI than FDG. Larger studies are required for the differentiation of malignant and benign mediastinal masses with FAPI.

68 GA-FAPI-04 PET/CT Versus 18 F-FDG PET/CT in Imaging of Malignant Mixed Germ Cell Testicular Tumor.

ABSTRACT: 18 F-FDG PET/CT imaging was performed for restaging in in a 16-year-old boy who was operated on for right testicular tumor and was diagnosed with malignant mixed germ cell tumor. Mild FDG uptake was observed in 2 nodules in both lungs and retroperitoneal lymph node in the abdomen. 68 Ga-FAPI (fibroblast activation protein inhibitor) 04 PET/CT showed moderate uptake of FAPI in lung nodules and retroperitoneal lymph node. In this case, 68 Ga-FAPI-04 PET/CT was shown to be superior to 18 F-FDG PET/CT in the evaluation of malignant mixed germ cell testicular tumor metastases.

The prognostic role of whole-body volumetric 68 GA-DOTATATE PET/computed tomography parameters in patients with gastroenteropancreatic neuroendocrine tumor treated with 177 LU-DOTATATE.

OBJECTIVE: The aim of this study is to evaluate the prognostic role of Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and quantitative 68 Ga-DOTATATE PET/computed tomography parameters such as maximum standardized uptake value (SUVmax), mean SUV (SUVmean), DOTATATE tumor volume (DTV), total lesion DOTATATE (TLD) in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) treated with 177 Lu-DOTATATE. MATERIAL AND METHOD: Our retrospective study included 21 patients with GEP-NETs treated with 177 Lu-DOTATATE between January 2017 and January 2022. SUVmax, SUVmean, SUVmax/spleenSUVmax (SUVmax/Sx), DTV, TLD, SUVmean/spleenSUVmean (SUVmean/Sm), TLD/Sm values were calculated and recorded for all patients before and after 177 Lu-DOTATATE treatment. RESULTS: A total of 319 metastases were detected in the patients included in the study, and a total of 68 target lesions were selected. In univariant Cox regression analysis, TLD/Sm percent change (∆TLD/Sm) was found to be statistically significant on overall survival (OS) ( P  = 0.044). The 3-year survival in nonresponders was 50% ( P  = 0.034) based on ∆SUVmax/Sx values, 50% ( P  = 0.002) based on RECIST values, 50% based on ∆TDTV + new lesion values ( P  = 0.033), and according to ∆TTLD + new lesion values, it was 66% ( P  = 0.030). CONCLUSION: In our study, we showed that SUVmax/Sx, RECIST, ∆TDTV + new lesion, and ∆TTLD + new lesion parameters can predict OS in the evaluation of response to treatment.

The Role of 68Ga FAPI-04 and 18F-FDG PET/CT in Detecting Liver Metastases in Different Types of Cancer.

OBJECTIVE: We compared the diagnostic accuracies of 68Ga FAPI-04 PET/CT and 18F-FDG PET/CT for detecting liver metastases (LMs) in patients with different cancer types. MATERIALS AND METHODS: This retrospective study included 63 patients with liver lesions who underwent 18F-FDG PET/CT and 68Ga-FAPI-04 PET/CT between May 2020 and May 2022. Patients with histopathologically confirmed primary diagnoses, data that could be accessed retrospectively, liver lesions confirmed by biopsy over at least 3-6 months of follow-up (via ultrasonography, CT, magnetic resonance imaging, PET/CT, or laboratory tests) were included. Patients with secondary malignancies or primary liver malignancies, and/or who could not be followed-up, were excluded. RESULTS: Of the 63 total patients, 34 (54%) were female, and the mean age was 61 (30-92) years. There were 582 LMs in 51 patients and 35 benign liver lesions in 20 (12 patients had only benign and 8 both benign and malignant lesions). Of the 582 LMs, 472 (81.1%) evidenced 18F-FDG uptake and 572 (98.2%) 68Ga-FAPI uptake. The diagnostic accuracies of 68Ga-FAPI PET/CT and 18F-FDG PET/CT were 98% and 82%, respectively (p < 0.001; McNemar test). When the LMs were compared, the maximum standardized uptake (SUVmax) value was significantly higher on 18F-FDG PET/CT than 68Ga-FAPI PET/CT (median: 6.0 vs. 5.4; p = 0.016). However, the LM-to-background ratio (TBR) was significantly higher on 68Ga-FAPI PET/CT than 18F-FDG PET/CT (median: 4.1 vs. 2.1; p < 0.001). CONCLUSION: 68Ga-FAPI PET/CT detected more LMs than did 18F-FDG PET/CT, and TBR was significantly higher on 68Ga-FAPI PET/CT than 18F-FDG PET/CT.

Role of volumetric parameters obtained from 68 Ga-PSMA PET/CT and 18F-FDG PET/CT in predicting overall survival in patients with mCRPC receiving taxane therapy.

OBJECTIVE: The aim of this study was to determine the prognostic role of volumetric parameters and Pro-PET scores obtained from 68 Ga-prostate-specific membrane antigen (PSMA) PET/CT and 18F-FDG PET/CT in patients with metastatic castration-resistant prostate cancer (mCRPC) receiving taxane therapy. MATERIALS AND METHODS: The study included 71 patients who underwent simultaneous PSMA and 18F-FDG PET/CT imaging between January 2019 and January 2022, had a Pro-PET score of 3-5 and had received taxane therapy after imaging. 18F-FDG tumor volume (TV-F) and PSMA tumor volume (TV-P) values of the lesions and total lesion glycolysis (TL-G) and total lesion PSMA (TL-P) values of the lesions were calculated on both imaging studies and the effects of these parameters on overall survival (OS) were investigated. RESULTS: The median age of the patients included herein was 71 years (56-89) and the median prostate-specific antigen (PSA) level was 16.4 (0.01-1852 ng/dL). According to the Kaplan-Meier survival analysis, TTV-P ≥ 78.5, TTL-P ≥ 278.8, TTV-F ≥ 94.98, TTL-G ≥ 458.3, TTV-P + F ≥ 195.45, TTL-G + P ≥ 855.78, lymph node (L)TV-FDG ≥ 3.4, LFDG-SUVmax ≥ 3.2, LFDG-SUVmean ≥ 2.25, LFDG-SUVpeak ≥ 2.55, and bone (B)TV-F ≥ 51.15 values were found to be prognostic factors in predicting short OS. Multivariate Cox regression analysis showed that a Vscore ≥ 3 (95% confidence interval [CI]: 7.069-98.251, p < 0.001) and TTL-G + P ≥ 855.78 (95% CI: 4.878-1037.860, p = 0.006) were found to be independent prognostic factors in predicting short OS. CONCLUSION: Volumetric parameters and Pro-PET scores obtained from 68 Ga-PSMA PET/CT and 18F-FDG PET/CT imaging have been shown to have an impact on OS in patients with mCRPC receiving taxane therapy.

18 F-FDG PET/CT parameters for prediction of response to neoadjuvant therapy and prognosis in rectal cancer.

OBJECTIVE: This study aims to investigate the role of F-18 fluorodeoxyglucose PET/computed tomography (18F-FDG PET/CT) parameters in the prediction of treatment response and the prognosis in locally advanced rectal cancer. METHODS: We investigated the relationship of 18F-FDG PET/CT parameters [rectal metabolic tumor volume (MTV), rectal total lesion glycolysis (TLG), rectal standard uptake value (SUV) max, rectal highest peak SUV, lymph node MTV, lymph node TLG, lymph node highest peak SUV] with the pathological response and disease-free survival (DFS) in 60 patients who received neoadjuvant therapy for a diagnosis of locally advanced rectal cancer. Patients with a total score of 0 were assigned to the low-risk group, patients with a score of 1 were assigned to the intermediate-risk group and patients with a score of 2 were assigned to the high-risk group. RESULTS: The multivariate analysis revealed that, from baseline PET CT parameters, lymph node highest peak SUV strongly predicted the pathological response at a cutoff value of 2.23. DFS was predicted by the lymph node highest peak SUV at a cutoff value of 3.13 and by the MTV value at a cutoff value of 27 cm 3 . The risk scoring performed with regard to rectal MTV and lymph node highest peak SUV values determined a median DFS of 19 months in patients with a risk score of 2, whereas the median DFS was not reached in patients with risk scores of 0 and 1 (P < 0.001). CONCLUSION: This study determined that rectal MTV and lymph node highest peak SUV predicted the response to neoadjuvant therapy and DFS.