Postoperative Positron Emission Tomography Research Articles

Clinical significance of the maximum standardized uptake value on positron emission tomography to predict treatment response and outcomes in patients with rectal cancer undergoing neoadjuvant chemoradiotherapy.

The association between the reduction rate of the maximum standardized uptake value (SUVmax) on positron emission tomography (PET) during neoadjuvant chemoradiotherapy (NACRT) and the prognosis in patients with locally advanced rectal cancer is unknown. We retrospectively analyzed 62 patients with locally advanced rectal cancer who underwent curative surgery after NACRT at Kobe University between 2008 and 2021. The SUVmax reduction rate was calculated from preoperative and postoperative PET scans, and its association with the prognosis was investigated. The cutoff value for SUVmax reduction rate was 61.5%. Twenty patients had an SUVmax reduction rate > 61.5% (SUV responder group) and 38 patients had an SUVmax reduction rate ≤ 61.5% (SUV nonresponder group). Regarding pathological outcomes, the rate of a good histological response was significantly higher in the SUV responder group than in the SUV nonresponder group (80.0% vs. 21.1%, p < 0.001). Both the overall (OS) and relapse-free survival (RFS) rates were significantly better in the SUV responder group than in the SUV nonresponder group (OS, p = 0.035; RFS, p = 0.019). In the SUV responder group, only 1 case of recurrence was observed, with a median follow-up period of 56months. The rate of SUVmax reduction during NACRT might predict the long-term prognosis of patients with locally advanced rectal cancer.

Postoperative positron emission tomography–computed tomography (PET-CT) in patients (Pts) with pathological stage III colon cancer (CC): Results from the first prospective validation study.

3621 Background: A significant proportion of pts with pathological stage III CC recur despite the absence of metastatic disease on pre-operative imaging. In a previous large retrospective study from our group on 348 pts, we reported that early postoperative PET-CT modified the staging and management of 13.4% of pathological stage III CC pts. The aim of the current study was to prospectively validate these findings. Methods: A prospective, single-center study of pts with pathological stage III CC who underwent early postoperative PET-CT (&lt; 3 months from surgery) between the years 2013-2023. All pts had no evidence of overt or equivocal metastatic disease at pre-operative CT-based imaging. Results: 144 pts were accrued and 134, 50% males, median age 67 years (range, 21-92) were evaluable for the primary endpoint i.e. early postoperative PET-CT results. Pathological stage was IIIA, IIIB and IIIC in 9 (6.7%), 81 (60.4%) and 44 (32.8%) pts, respectively. The median number of lymph nodes examined and of positive nodes were 19 (range, 6-134) and 2 (range, 0-26), respectively. The median time from surgery to PET-CT was 1.7 months (range, 0.9-3.2). Post-operative PET-CT findings were significant in 18 pts (13.4%): 12 pts (9.0%) were upstaged to stage IV, 4 (3.0%) were diagnosed with a second primary malignancy, 1 (0.7%) was both upstaged and diagnosed with another cancer and one pt (0.7%) had local recurrence. Metastatic sites identified by the PET-CT were liver (9 pts), peritoneum (4), lymph nodes (2) and lung (1), and the second malignancies detected by the test were breast in 2 pts and thyroid, palatine tonsil and rectum in one pt each. Of the 13 pts found to have metastatic disease, 5 (38.4%) underwent potentially curative surgery. At a median follow-up of 39.0 months (range, 4.7–123.3), 20 of the 116 pts (17.2%) with true stage III CC recurred; the estimated 3-year disease-free survival rate was 83.9%. The estimated 5-year overall survival rate for the entire cohort was 85.2%; the rates for true stage III pts and for pts found to have metastatic disease were 89.8% and 56.2%, respectively ( P&lt;0.0001). Conclusions: Results from the first prospective study to evaluate the role of early postoperative PET-CT in pts with pathological stage III CC have validated earlier retrospective data: the use of PET-CT in this setting changed the staging and management of 13.4% of pts, allowing early detection of potentially curable metastatic disease or other malignancies. Moreover, the stage migration phenomenon observed in our study, seems to have an impact on the pts overall outcome, compared to the literature. In light of the accumulating data from our center, suggesting a favorable cost-benefit of early postoperative PET-CT in pathological stage III CC, incorporation of the test into the routine management of these pts should be considered.

Use of Postoperative PET/CT in Altering Management in Adjuvant Head and Neck Radiation Therapy

Routine clinical practice does not include postoperative positron emission tomography (PET)/CT prior to postoperative radiation therapy (PORT) for head and neck cancer. Besides logistical challenges in obtaining postoperative PET/CT within six weeks after surgery, interpreting PET/CT findings in the postoperative setting can also be difficult. However, given the potential for residual or rapidly recurrent disease, postoperative PET/CT may help identify the need for additional diagnostic evaluation or alter adjuvant therapy. There are limited data evaluating the utility of postoperative PET/CT prior to PORT for head and neck cancer. We sought to evaluate the use and clinical relevance of postoperative PET/CT prior to PORT. In this retrospective, single-institution cohort study, we identified patients with head and neck cancer between 2013 and 2020 who received a postoperative PET/CT prior to PORT. We extracted electronic medical record data supplemented with manual chart review to collect patient and disease-related information. We measured the rates of additional diagnostic workup and treatment alterations as a result of postoperative PET/CT findings. The cohort included 29 patients who received a postoperative PET/CT prior to PORT. The mean age at diagnosis was 60.8 years (standard deviation: 15.0 years) and 20 (69.0%) were male. Regarding primary site, 10 (34.5%) were oropharynx, 7 (24.1%) were salivary gland, and 6 (20.7%) were oral cavity. The mean time from surgery to postoperative PET was 40.9 days (standard deviation: 27.7 days), and the mean time from postoperative PET/CT to start of PORT was 22.4 days (standard deviation: 20.3 days). A total of 9 (31.0%) patients experienced a change in management as a result of the PET/CT findings. Six (66.7%) patients received a biopsy. All 9 patients had a change in their radiation treatment plan, either dose escalation, target change, or in one case, converting to palliative dosing. Six (66.7%) patients were recommended addition of chemotherapy as a result of additional workup, with 4 (44.4%) of those patients ultimately receiving chemotherapy. Three (33.3%) patients underwent re-resection prior to PORT. In patients with head and neck cancer who received postoperative PET/CT prior to PORT, a meaningful proportion underwent additional diagnostic evaluation and/or experienced an alteration in adjuvant therapy as a result of the imaging findings. Interestingly, all patients with abnormal postoperative PET findings had changes in their radiation treatment plan, including at least boosting gross disease for patients in whom re-resection or chemotherapy was not pursued. Future work will seek to expand this cohort through 2022 when postoperative PET/CT became more routine at our institution and include oncologic outcomes. Additional studies are needed to identify appropriate candidates for postoperative PET/CT and determine the clinical impact of postoperative PET/CT.

Effects of Bilateral Subthalamic Nucleus Stimulation on Depressive Symptoms and Cerebral Glucose Metabolism in Parkinson's Disease: A 18F-Fluorodeoxyglucose Positron Emission Tomography/Computerized Tomography Study.

Subthalamic nucleus (STN) deep brain stimulation (DBS) can improve motor symptoms in Parkinson’s disease (PD), as well as potentially improving otherwise intractable comorbid depressive symptoms. To address the latter issue, we evaluated the severity of depressive symptoms along with the severity of motor symptoms in 18 PD patients (mean age, 58.4 ± 5.4 years; 9 males, 9 females; mean PD duration, 9.4 ± 4.4 years) with treatment-resistant depression (TRD) before and after approximately 1 year of STN-DBS treatment. Moreover, to gain more insight into the brain mechanism mediating the therapeutic action of STN-DBS, we utilized 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) to assess cerebral regional glucose metabolism in the patients at baseline and 1-year follow-up. Additionally, the baseline PET data from patients were compared with PET data from an age- and sex-matched control group of 16 healthy volunteers. Among them, 12 PD patients underwent post-operative follow-up PET scans. Results showed that the severity of both motor and depressive symptoms in patients with PD-TRD was reduced significantly at 1-year follow-up. Also, patients used significantly less antiparkinsonian medications and antidepressants at 1-year follow-up, as well as experiencing improved daily functioning and a better quality of life. Moreover, relative to the PET data from healthy controls, PD-TRD patients displayed widespread abnormalities in cerebral regional glucose metabolism before STN-DBS treatment, which were partially recovered at 1-year follow-up. Additionally, significant correlations were observed between the patients’ improvements in depressive symptoms following STN-DBS and post-operative changes in glucose metabolism in brain regions implicated in emotion regulation. These results support the view that STN-DBS provides a promising treatment option for managing both motor and depressive symptoms in patients who suffer from PD with TRD. However, the results should be interpreted with caution due to the observational nature of the study, small sample size, and relatively short follow-up.

Survival benefit associated with postoperative PET–CT before adjuvant radiotherapy or chemoradiotherapy in patients with oral squamous cell carcinoma

The aim of this study was to analyse the impact of postoperative positron emission tomography–computed tomography (PET–CT) before adjuvant treatment in oral squamous cell carcinoma (OSCC) patients. Patients with OSCC requiring adjuvant treatment following surgery were divided retrospectively into two groups based on the implementation of PET–CT. The study endpoints were disease-specific survival (DSS) and overall survival (OS). A total of 123 patients underwent PET–CT examination; 28 had abnormal images, but only seven were confirmed to be pathologically positive. A total of 145 patients underwent computed tomography/magnetic resonance imaging (CT/MRI) examination; 20 had abnormal images, but only one was confirmed to be pathologically positive. The median OS time was 5.4 years in the PET–CT group and 4.3 years in the CT/MRI group, demonstrating a significant difference (P = 0.024). Findings were similar for the median DSS time. In patients with positive PET–CT results, the median DSS was 4.3 years and median OS was 3.5 years, and in those with negative PET–CT results, the median survival time could not be calculated as fewer than 50% of patients reached these endpoints; both differences were significant (P = 0.007 and P < 0.001). Although the false-positive rate of postoperative PET–CT is high, it improves the chance of survival through early and more frequent detection of recurrence.

Breast metastasis from medullary thyroid carcinoma: a report of a case

BackgroundMetastasis to the breast is rare. We herein report a patient with metastatic medullary thyroid carcinoma to the breast for whom measuring the calcitonin level was an important clue to the correct diagnosis.Case presentationA 54-year-old woman visited our hospital for the treatment of recurrent metastatic medullary thyroid carcinoma due to multiple endocrine neoplasia 2A and breast cancer. Positron emission tomography performed before the operation for metastatic medullary thyroid carcinoma recurrence in the neck showed the accumulation of 18F-fluorodeoxyglucose in the bilateral breast at sites other than the disease in the neck. Ultrasonography revealed multiple tumors in both breasts. A core needle biopsy of three breast tumors was performed. Microscopically, the tumor cells showed solid growth and did not show a tubular structure. She was diagnosed with triple-negative invasive ductal carcinoma. Post-operative positron emission tomography was performed as the serum calcitonin level increased after the operation. The accumulation of 18F-fluorodeoxyglucose in the bilateral breast tumors and lymph nodes in the neck was noted. The possibility of the breast tumors being metastasis of metastatic medullary thyroid carcinoma was considered. Needle aspiration was performed for three breast tumors. The calcitonin level of the washout fluid was measured and found to be ≥ 17,500 pg/mL. Immunohistochemistry showed that the tumor cells were calcitonin-positive and gross cystic disease fluid protein-15-negative. Vandetanib was started as recurrent metastatic medullary thyroid carcinoma with breast metastasis was finally diagnosed. The serum calcitonin level decreased after 1 month.ConclusionAlthough breast metastasis of medullary thyroid carcinoma is rare, a correct diagnosis is indispensable for appropriate treatment. When a breast tumor shows atypical morphological features for breast cancer according to the histopathology in a patient with a history of cancer, metastasis to the breast should be considered. Calcitonin measurement of the needle washout fluid was useful for confirming metastatic medullary thyroid carcinoma.

Mesolimbic opioid-dopamine interaction is disrupted in obesity but recovered by weight loss following bariatric surgery

Obesity is a growing burden to health and the economy worldwide. Obesity is associated with central µ-opioid receptor (MOR) downregulation and disruption of the interaction between MOR and dopamine D2 receptor (D2R) system in the ventral striatum. Weight loss recovers MOR function, but it remains unknown whether it also recovers aberrant opioid-dopamine interaction. Here we addressed this issue by studying 20 healthy non-obese and 25 morbidly obese women (mean BMI 41) eligible for bariatric surgery. Brain MOR and D2R availability were measured using positron emission tomography (PET) with [11C]carfentanil and [11C]raclopride, respectively. Either Roux-en-Y gastric bypass or sleeve gastrectomy was performed on obese subjects according to standard clinical treatment. 21 obese subjects participated in the postoperative PET scanning six months after bariatric surgery. In the control subjects, MOR and D2R availabilities were associated in the ventral striatum (r = .62) and dorsal caudate (r = .61). Preoperatively, the obese subjects had disrupted association in the ventral striatum (r = .12) but the unaltered association in dorsal caudate (r = .43). The association between MOR and D2R availabilities in the ventral striatum was recovered (r = .62) among obese subjects following the surgery-induced weight loss. Bariatric surgery and concomitant weight loss recover the interaction between MOR and D2R in the ventral striatum in the morbidly obese. Consequently, the dysfunctional opioid-dopamine interaction in the ventral striatum is likely associated with an obese phenotype and may mediate excessive energy uptake. Striatal opioid-dopamine interaction provides a feasible target for pharmacological and behavioral interventions for treating obesity.

A case of simultaneous abdominal wall metastasis of hepatocellular carcinoma with long-term relapse-free survival after laparoscopic resection

We report our experience of an extremely rare case of a simultaneous extrahepatic metastasis of hepatocellular carcinoma (HCC) with long-term relapse-free survival, treated by laparoscopic resection of an abdominal wall tumor and subsequent radiofrequency ablation (RFA) of an intrahepatic lesion. A 76-year-old man visited a local clinic for right lower abdominal pain. He was treated with antibiotics and the symptom resolved. However, a mass was detected in the same region and he was referred to our hospital for further evaluation. Computed tomography (CT) of the abdomen showed a mass 5 cm in diameter, raising suspicions of an intra-abdominal tumor. Laparoscopic surgery was performed, and the tumor was found in the abdominal wall and completely resected. Histopathological examination yielded a diagnosis of extrahepatic HCC. Post-operative positron emission tomography (PET)-CT showed increased uptake of fluorodeoxyglucose in segment 3 (S3) of the liver. On performing a liver biopsy, HCC was diagnosed. Subsequently, the S3 lesion was treated with radiofrequency ablation. The patient has remained relapse-free for 6 years without further treatments.

Immature teratoma in pregnancy

Objective: The most common genital neoplasms in the reproductive period are over tumors. Limitation of radiological examinations done during pregnancy and the concentration of the examination on the fetus in general may lead to missed malignancies. The purpose of the study is to discuss the approach to adnexal masses seen in pregnancy. Case: A 26-year-old woman with a 39-week gestation had a groin pain. CA125 value: 60 U / ml, CA19-9: 385,5 U / ml, AFP: 115,1 U / ml. After birth with C / S, the right ovary was observed to have a mass of approximately 15 cm It was followed. The mass was excised and a frozen section was sent. It was reported to be compatible with the resultant mature teratoma. Upon reporting the final pathologic outcome as immature teratoma grade 1, post-operative positron emission tomography (PET-CT) imaging and tumor marker screening were planned. PET CT imaging and tumor markers were negative. Conclusions: 90% of adnexal masses below 6 cm are functional cysts between the 16-18th gestational weeks. They usually fall back on their own. Malignancy rate after operation is 4-6% in persistent. Except for the presence of acute symptoms or the suspicion of serious malignancy; Surgical intervention should be postponed to the middle of the 2nd trimester (16-18th week). The presence of ovarian cysts with symptomatic ovarian mass presence, overtorsion, overcyst rupture, acute abdomen, diffuse ascites, rapid growth pattern in pregnancy requires urgent surgical intervention. Frozen section should be sent during the operation if surgical intervention is required. The frozen section determines intraoperative behavior. The number of cross sections during frozen process is limited. In frozen conditions, as many as three sections can be taken in the laboratory, large-diameter tumors have a higher rate of false diagnosis in the frozen specimen. As in this case, inadequate sampling leads to false negative results in borderline and malign lesions showing focal development. Although this delay in diagnosis causes adjuvant delay in treatment, ovarian cancer that is detected in pregnancy is usually over-limited (stage 1), so the outcome is not badly affected. Most of them are germ cell tumors and low malignant potential epithelial tumors. It usually shows early stage, low grade, unilaterality. Often, unilateral oophorectomy and surgical staging are sufficient.

NIMG-42. EXPERIENCE WITH 18F-FET PET/MRI FOR CNS-TUMORS IN CHILDREN AND ADOLESCENTS

Positron Emission Tomography (PET) with 18F-fluoro-ethyltyrosine (18F-FET) improves diagnostic accuracy in adult patients with gliomas but the literature in pediatric neuro-oncology is still scarce. We aimed 1) to collect a material of various pediatric brain tumors 2) to determine sensitivity and specificity for tumor using 18F-FET PET versus MRI alone 3) to test the clinical impact of the scans. Eighty patients with primary pediatric CNS-tumors was included and a total of 121 hybrid 18F-FET PET/MRI or PET/CT scans have been performed. Clinical impact was assessed as minor (change of diagnosis) or major (change of treatment plan). Minor impact was seen in 28% of all scans and major impact in 9%. In the 27 cases, when a PET scan had beforehand been regarded clinically indicated, 38% showed minor impact and 35% showed major impact. A high uptake was seen in pilocytic astrocytoma and in high grade gliomas, while lower uptake was seen in e.g. AT/RT (atypical teratoid/rhabdoid tumor), ependymoma, germinomas. No increased uptake was seen in e.g. non-contrast enhancing low grade glioma. In 24 early postoperative 18F-FET PET scans conducted primarily within 72 hours after surgery, minor impact was seen in 42% and major impact in 4% of cases. Based on a consensus reading for residual tumor of follow-up scans (up to 24 months), we found the following lesion-based sensitivity/specificity/accuracy for diagnosing residual tumor: MRI alone: 80%/64%/72%. PET/MRI: 73%/100%/86%. The addition of 18F-FET PET to MRI for imaging of pediatric CNS-tumors has a major impact on the clinical management in 9% of all scans and in 35% of the clinically indicated scans. The addition of 18F-FET PET for early postoperative imaging seems to increase the specificity for residual tumor and should be considered when radical surgery is of high priority, especially if MRI is equivocal.

NIMG-34THE PROGNOSTIC VALUE OF POSTOPERATIVE O-(2-18F-FLUOROETHYL)-L-TYROSINE POSITRON EMISSION TOMOGRAPHY IN NEWLY DIAGNOSED GLIOBLASTOMA

BACKGOUND: Patients with glioblastoma (GBM) show a variable disease course ranging from rapid progression to prolonged progression free survival (PFS). Despite aggressive standard therapy consisting of radiotherapy plus concomitant and adjuvant temozolomide (RCX) the prognoses is poor with a median overall survival (OS) less than 15 months and 5-year overall survival less than 10%. To maximize patient survival and optimize quality of life, it is relevant to identify prognostic biomarkers for treatment stratification. Positron emission tomography (PET) scanning using radiolabeled amino acids has been introduced in the radiation therapy planning of GBM. Therefore this study will evaluate whether postoperative FET PET in newly diagnosed GBM can provide additional prognostic information on outcome. MATERIALS AND METHODS: 147 patients from our GBM database treated with RCX and evaluated with FET PET postoperatively (1-2 weeks) in the period November 2011 - February 2014 were included retrospectively. With OS as the primary endpoint, and PFS as a secondary endpoint, the prognostic value of postoperative biological tumor volume (BTV) in FET PET, mean tumor to background ratio (TBRmean) and maximum tumor to background ratio (TBRmax) was estimated using Cox proportional hazards model. The analysis was adjusted for the known prognostic factors, performance status (PS), age and corticosteroid therapy status, by multivariate analysis. RESULTS: Median OS and PFS were 14.0 and 6.54 months respectively. In the univariate analysis, increasing BTV and higher values of TBRmean and TBRmax correlated significantly (<0.0001) with poor OS and PFS. In the multivariate analysis increasing BTV, poor PS and high age was independent prognostic factors for poor OS and PFS with p-values < 0.0001. CONCLUSION: Increasing postoperative FET PET tumor volume is an important independent prognostic factor of poor OS and PFS for GBM patients. Underlining the importance, of maximal tumor resection, on OS.

Early [18F]FET-PET in Gliomas after Surgical Resection: Comparison with MRI and Histopathology.

BackgroundThe precise definition of the post-operative resection status in high-grade gliomas (HGG) is crucial for further management. We aimed to assess the feasibility of assessment of the resection status with early post-operative positron emission tomography (PET) using [18F]O-(2-[18F]-fluoroethyl)-L-tyrosine ([18F]FET).Methods25 patients with the suspicion of primary HGG were enrolled. All patients underwent pre-operative [18F]FET-PET and magnetic resonance imaging (MRI). Intra-operatively, resection status was assessed using 5-aminolevulinic acid (5-ALA). Imaging was repeated within 72h after neurosurgery. Post-operative [18F]FET-PET was compared with MRI, intra-operative assessment and clinical follow-up.Results[18F]FET-PET, MRI and intra-operative assessment consistently revealed complete resection in 12/25 (48%) patients and incomplete resection in 6/25 cases (24%). In 7 patients, PET revealed discordant findings. One patient was re-resected. 3/7 experienced tumor recurrence, 3/7 died shortly after brain surgery.ConclusionEarly assessment of the resection status in HGG with [18F]FET-PET seems to be feasible.

Variation in positron emission tomography use after colon cancer resection.

Colon cancer surveillance guidelines do not routinely include positron emission tomography (PET) imaging; however, its use after surgical resection has been increasing. We evaluated the secular patterns of PET use after surgical resection of colon cancer among elderly patients and identified factors associated with its increasing use. We used the SEER-linked Medicare database (July 2001 through December 2009) to establish a retrospective cohort of patients age ≥ 66 years who had undergone surgical resection for colon cancer. Postoperative PET use was assessed with the test for trends. Patient, tumor, and treatment characteristics were analyzed using univariable and multivariable logistic regression analyses. Of the 39,221 patients with colon cancer, 6,326 (16.1%) had undergone a PET scan within 2 years after surgery. The use rate steadily increased over time. The majority of PET scans had been performed within 2 months after surgery. Among patients who had undergone a PET scan, 3,644 (57.6%) had also undergone preoperative imaging, and 1,977 (54.3%) of these patients had undergone reimaging with PET within 2 months after surgery. Marriage, year of diagnosis, tumor stage, preoperative imaging, postoperative visit to a medical oncologist, and adjuvant chemotherapy were significantly associated with increased PET use. PET use after colon cancer resection is steadily increasing, and further study is needed to understand the clinical value and effectiveness of PET scans and the reasons for this departure from guideline-concordant care.

Laparoscopic Anterior Exenteration With Intracorporeal Uretero-Sigmoidostomy

To demonstrate the feasibility of laparoscopic anterior exenteration with intracorporeal ureterosigmoidostomy. After Institutional Review Board approval was obtained, patients who had undergone laparoscopic anterior exenteration with intracorporeal ureterosigmoidostomy were analyzed. Fifty-seven patients with advanced cervical carcinoma, stage IV A, since 2005 were analyzed retrospectively. The preoperative workup was done with contrast-enhanced computed tomography abdomen-pelvis and positron emission tomography (PET) scans. Patients were analyzed for operative time, blood loss, and complications. Patient follow-up was done monthly for the first 3 months, every 3 months for 1 year, and then every 6 months for 3 years. Postoperative follow-up was done with PET scans. Galaxy Care Laparoscopic Institute, Pune, India. Operative steps were as follows: The mean operative time was 180 minutes (range, 140-240 minutes), and mean blood loss was 100 mL (range, 50-200 mL), as measured by the amount of blood in the suction machine. The median duration of hospital stay was 4 days (range, 3-7 days). The mean number of lymph nodes retrieved was 12 (range, 9-21). Surgical margins were negative in all patients with a lateral margin >2 cm. Twenty-eight patients had positive lymph nodes. Chemoradiotherapy was given to the patients with positive lymph nodes. Minor leak was present in 11 patients in the immediate postoperative period, for which no active intervention was required. Hyperchloremic metabolic acidosis which was seen on biochemical parameter but clinically patient have no manifestation and was treated with sodium bicarbonate. A postoperative PET scan was done at 6 months after the completion of adjuvant therapy in lymph node-positive patients and 6 months after surgery in node-negative patients. Exenteration has a definitive role in the treatment of advanced cervical cancer. Results have demonstrated the feasibility of this procedure [1-4].

Management of sarcomatoid salivary duct carcinoma of the submandibular gland duct with coexisting seropositive human immunodeficiency virus

Sarcomatoid salivary duct carcinoma of the submandibular gland is extremely rare. This paper highlights the impact of surgery and adjuvant radiation therapy on the outcome of this disease. A 59-year-old man with human immunodeficiency virus presented with a painless, rapidly growing left neck mass. Biopsy followed by surgical excision of the left submandibular gland revealed sarcomatoid salivary duct carcinoma of the submandibular gland duct with perineural invasion and close margins, for which he underwent adjuvant radiotherapy. Post-operative positron emission tomography and computed tomography revealed no residual or metastatic disease. Pathological analysis of tumour-node-metastasis staging revealed a T2 N0 M0 (stage II) tumour. The patient tolerated his treatment without serious acute or long-term side effects. There was no evidence of disease on comprehensive examination or on positron emission tomography or computed tomography scans at the 4.6-year follow up. Surgery followed by adjuvant radiotherapy provided practical locoregional control with acceptable toxicity. Further detailed case reports are warranted to optimise the management of this rare malignancy.

Intraoperative tissue fluorescence using 5-aminolevolinic acid (5-ALA) is more sensitive than contrast MRI or amino acid positron emission tomography (18F-FET PET) in glioblastoma surgery

Objective: The sensitivity of 5-aminolevolinic acid (5-ALA) in detecting intraoperative glioblastoma (GBM) tissue compared to postoperative 18F-fluoroethyl-L-tyrosine and T1 contrast uptake of tumor cells in positron emission tomography (PET) and magnetic resonance imaging (MRI) scans was investigated in a retrospective image correlative study.Methods: Ten patients with histological verified GBM in eloquent brain regions underwent 11 surgeries with neuronavigation and 5-ALA assisted tumor resection. Residual 5-ALA fluorescence was labeled intraoperatively on the navigation MRI scans and images were fused with postoperative 18F-FET PET and T1 contrast MRI.Results: Intraoperatively, at the end of save resection, in all patients 2–5 faint 5-ALA positive resection planes were detected (mean 3·6), compared to 0–4 18F-FET positive resection planes (mean 1·4) and 0–2 positive T1 contrast MRI resection planes in postoperative scans. The difference between the number of 5-ALA and 18F-FET positive resection planes was statistically significant (P = 0·0002). The histological investigation of 5-ALA positive resection margins demonstrated infiltrative tumor in every case. Residual 5-ALA fluorescence on resection margins and postoperative 18F-FET uptake areas or residual contrast T1 areas were colocalized in all cases, documented by pre-/postoperative image fusion.Conclusion: Residual faint 5ALA uptake is documented in large areas at the end of GBM resection and corresponds to tumor infiltration. These 5-ALA positive resection plans exceeded the 18F-FET uptake areas in postoperative PET scans. Thus, intraoperative 5-ALA residual fluorescence seems to be a more sensitive marker than 18F-FET PET for residual tumor in malignant gliomas.

Post-operative changes of cerebral circulation and metabolism in the acute stage of low-grade aneurysmal subarachnoid hemorrhage

Objective: Pre- and post-operative cerebral circulation and metabolism were evaluated in patients with low-grade acute aneurysmal subarachnoid hemorrhage (SAH) who underwent early surgery to investigate the effects on brain dysfunction.Methods: Positron emission tomography (PET) was performed to measure the regional cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO2), oxygen extraction fraction (OEF) and cerebral blood volume in four patients (one male and three females, mean age: 60.3 years) with low-grade SAH within 30 hours of onset. Post-operative PET was performed on the seventh post-operative day. No patient suffered clinical deterioration during the study. Pre-operative PET scans demonstrated significant global reduction of CBF and CMRO2, compared to 16 normal control subjects, and no significant change in OEF. CBF and CMRO2 reduction post-operatively improved to the normal control values. Post-operative OEF was significantly increased compared to the normal control value.Conclusions: Patients with low-grade SAH have impairment of cerebral circulation and metabolism in the acute period, which improves after surgery. Early surgery for low-grade SAH, necessary to avoid rerupture of the aneurysm, did not worsen the impairment of cerebral circulation and metabolism. However, measures to protect the brain from perioperative damage are necessary to achieve the optimum outcome.

Absence of microfollicular basement membrane: A new indicator in the diagnosis of follicular carcinoma thyroid

The thyroid follicles represent a biological continuum. Each follicle is closely related to the follicle that is next to it. The important feature of a follicular carcinoma is a microfollicular pattern. We report a case of follicular carcinoma in a 48-year-old female that demonstrates microfollicles which are larger in size and contain more number of follicular cells in cytologic smears (20-29 cells) in contrary to the literature definition of microfollicles containing approximately 6-12 cells. We also demonstrate absence of basement membranes in these microfollicles in histologic sections by Silver Methanamine Stain, which may be an indicator to search for vascular and capsular invasion. This case report also describes postoperative positron emission tomography scan findings.

Integrated positron emission tomography and magnetic resonance imaging–guided resection of brain tumors: a report of 103 consecutive procedures

The aim of this study was to evaluate the integration of positron emission tomography (PET) scanning data into the image-guided resection of brain tumors. Positron emission tomography scans obtained using fluorine-18 fluorodeoxyglucose (FDG) and L-[methyl-11C]methionine (MET) were combined with magnetic resonance (MR) images in the navigational planning of 103 resections of brain tumors (63 low-grade gliomas [LGGs] and 40 high-grade gliomas [HGGs]). These procedures were performed in 91 patients (57 males and 34 females) in whom tumor boundaries could not be accurately identified on MR images for navigation-based resection. The level and distribution of PET tracer uptake in the tumor were analyzed to define the lesion contours, which in turn yielded a PET volume. The PET scanning-demonstrated lesion volume was subsequently projected onto MR images and compared with MR imaging data (MR volume) to define a final target volume for navigation-based resection-the tumor contours were displayed in the microscope's eyepiece. Maximal tumor resection was accomplished in each case, with the intention of removing the entire area of abnormal metabolic activity visualized during surgical planning. Early postoperative MR imaging and PET scanning studies were performed to assess the quality of tumor resection. Both pre- and postoperative analyses of MR and PET images revealed whether integrating PET data into the navigational planning contributed to improved tumor volume definition and tumor resection. Metabolic information on tumor heterogeneity or extent was useful in planning the surgery. In 83 (80%) of 103 procedures, PET studies contributed to defining a final target volume different from that obtained with MR imaging alone. Furthermore, FDG-PET scanning, which was performed in a majority of HGG cases, showed that PET volume was less extended than the MR volume in 16 of 21 cases and contributed to targeting the resection to the hypermetabolic (anaplastic) area in 11 (69%) of 16 cases. Performed in 59 LGG cases and 23 HGG cases, MET-PET demonstrated that the PET volume did not match the MR volume and improved the tumor volume definition in 52 (88%) of 59 and 18 (78%) of 23, respectively. Total resection of the area of increased PET tracer uptake was achieved in 54 (52%) of 103 procedures. Imaging guidance with PET scanning provided independent and complementary information that helped to assess tumor extent and plan tumor resection better than with MR imaging guidance alone. The PET scanning guidance could help increase the amount of tumor removed and target image-guided resection to tumor portions that represent the highest evolving potential.

Functional evaluation of microvascular free flaps with positron emission tomography

The aim of this study was to assess blood flow (BF) of microvascular free flaps studied with positron emission tomography (PET) in patients with head and neck squamous cell cancer (HNSCC) undergoing major radical surgery 3-4 weeks after high-dose radiotherapy. Five patients underwent resection of the HNSCC of the oral cavity followed by microvascular reconstruction with a radial forearm flap. Regional BF in oral and neck tissues was measured with PET using radiolabelled water ([15O]H2O) twice (1-2 and 12-14 days, respectively) following radical surgery. In the first postoperative PET study, the median BF in the cutaneous flap area was 5.1 mL/100 g/min, and in the muscle contra-lateral to the recipient site 19.9 mL/100 g/min. A low flap-to-muscle BF ratio appeared to correlate with circulatory incongruity, and thus with poorer flap success. The follow-up study on the second postoperative week supported the results of the primary PET scan. This pilot study suggests that PET using [15O]H2O is a feasible method to quantitatively evaluate BF of the whole free flap in patients operated on for oral