Indian Journal of Nuclear Medicine最新文献

Gastric cancer is the fifth most common cancer and the third most common cause of cancer death globally. Advanced disease is often metastatic to the peritoneum, liver, and lung. Bone involvement is rare, and bone marrow dissemination is even rarer. Hematological abnormalities may arise as complications of metastatic gastric cancer. Therefore, knowledge about the possibility of gastric cancer spreading to bone marrow and causing hematological complications is necessary.

Intraosseous cavernous hemangiomas (OCHs) are benign vascular tumors most frequently located in the axial skeleton, including the skull, vertebrae, and pelvis. However, when they occur in the long bones, their clinical presentation may resemble malignancy, posing a diagnostic challenge. This case highlights a female patient with multiple OCHs in the femur, sternum, and humerus, mimicking malignant bone lesions. The report discusses the clinical features, radiological and pathological findings, the role of positron emission tomography-computed tomography in diagnosis, and management.

Introduction: The purpose of this study was to compare ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) and CT performance in guiding percutaneous biopsies with histologic confirmation of lung lesions.

Materials and methods: We prospectively evaluated 50 patients, of whom 25 underwent ¹⁸F-FDG PET/CT-guided biopsy and 25 underwent CT-guided biopsy. The pathology results, diagnostic performance, procedure duration, and complications in the two groups were evaluated.

Results: Of the 25 biopsies with PET/CT guidance, histology demonstrated a mean diagnostic accuracy of 97.62%. In the CT-guided group, the mean diagnostic accuracy was 85%. The t-test revealed a statistically significant difference (P < 0.00001).

Conclusion: PET/CT-guided biopsy of lung lesions led to fewer inconclusive biopsies than CT-guided biopsy, with similar complication rates. This study highlights that PET-CT-guided lung biopsies, especially when robot-assisted, provide superior diagnostic accuracy. Moreover, PET-CT-guided biopsies exhibit a high sensitivity and low complication rates, making them a reliable and safe option for biopsy procedures. However, limitations related to study design, procedural learning curves, and radiation exposure should be carefully considered.

Ischemia with nonobstructive coronary artery disease (INOCA) refers to patients who present with signs and symptoms of myocardial ischemia despite the absence of obstructive coronary artery disease. Coronary microvascular dysfunction (CMD) is one of the underlying causes of INOCA and is associated with an increased risk of major adverse cardiac events. CMD is often detected as impaired coronary flow reserve (CFR) during invasive coronary angiography. We hereby report a patient with microvascular angina (MVA), having impaired myocardial flow reserve and perfusion defects at cardiac positron emission tomography (PET) imaging. The patient demonstrated improved myocardial perfusion and dynamic PET parameters following medical management.

Glioblastoma multiforme (GBM) is a high-grade brain tumor with a high recurrence rate. We present the case of a 57-year-old man with left frontal lobe GBM who was operated on and received radiation therapy in June 2023 and was referred for ⁶⁸Ga-PSMA 11 PET/CT with a clinical suspicion of recurrence. The scan showed intense tracer uptake in the left frontal lobe lesion with severe edema, which was consistent with recurrence. Our case underscores the role of ⁶⁸Ga PSMA 11 PET/CT imaging of suspected glioblastoma recurrence which is the initial step in GBM theranostics with PSMA.

Background: The proliferation index (Ki-67 index) is a known independent prognostic marker in carcinoma breast, and its expression is directly proportional to higher recurrence and worse prognosis. However, there is no standard cutoff of the Ki-67 index to determine its low or high expression. In this study, we aim to find the association of various metabolic parameters on ¹⁸F FDG positron emission tomography/computed tomography (PET/CT) with Ki-67 index in carcinoma breast patients and further evaluate its correlation with low and high Ki-67 index groups.

Materials and methods: This is a retrospective study conducted in a tertiary hospital in North India between February 2021 and 2024. All histopathologically proven female cases of carcinoma breast with reported Ki-67 index and baseline ¹⁸F FDG PET/CT before any treatment or surgery were included. The metabolic parameters, namely, standardized uptake value (SUVmax), the metabolic ratio of the primary tumor to the liver (SUR), total lesion glycolysis (TLG), and metabolic tumor volume (MTV) were recorded for each case. The correlation between the metabolic parameters and the Ki-67 index was analyzed, and subgroup analysis was done.

Results: Sixty-five female patients met the inclusion criteria, and the majority of them presented with intraductal carcinoma. The median value (interquartile range [IQR]) of the Ki-67 index was 40% (IQR: 50%). The primary breast tumor showed median (IQR) of SUVmax, SUR, TLG, and MTV of 10.3 g/mL (7.2), 3.7 (2.9), 102.9 g.cub/mL (184.7), and 16.2 cm³ (25.4), respectively. A significant correlation was noted between all the metabolic parameters studied and the Ki-67 index. In subgroup analysis, a significant difference was noted in all the metabolic parameters between the subgroups of the Ki-67 index ≤25% versus >25%.

Conclusion: Metabolic parameters on ¹⁸F FDG PET/CT show a promising role in the determination of the status of proliferation marker Ki-67 index in carcinoma breast.

McCune-Albright syndrome is a rare and challenging disorder characterized by a triad of cutaneous, bone and multiple endocrine abnormalities. We present the case of a 15-year-old female with varied symptoms including precocious puberty, prolactinoma, polyostotic fibrous dysplasia, and hyperthyroidism. On examination, she had a palpable nodule in the right lobe of the thyroid with an atrophic left lobe on ultrasonography. Thyroid scan in this patient posed a diagnostic challenge which was resolved with additional single-photon emission computed tomography/computed tomography (SPECT/CT). On SPECT/CT, she was diagnosed with autonomously functioning thyroid nodule and treated with 15 mCi of ¹³¹I.

Intrathoracic kidney is very rare and has the lowest prevalence among all renal ectopias. We report the case of a 70-year-old male who was referred for diethylenetriaminepentaacetic acid (DTPA) scan as a part of presurgical work-up for a right renal mass. PriorUltrasonography abdomen incorrectly reported left kidney as normal in location. ^99mTc-DTPA renal scan combined with single-photon emission computed tomography - computed tomography revealed impaired global glomerular filtration rate with left kidney in ectopic (intrathoracic) location. 18-fluorodeoxyglucose positron emission tomography-computed tomography images revealed a soft tissue mass completely replacing the right kidney with metastases to bilateral lungs. This case reemphasizes the importance of nuclear medicine imaging in diagnosis and evaluation of the renal function of the intrathoracic kidney.

Among the thyroid malignancies, primary thyroid sarcomas are very rare, comprising < 1% of all thyroid malignancies. Sarcoma, in particular spindle cell sarcomas of the thyroid gland, is very rare and aggressive which carries poor prognosis. Very little has been published regarding imaging findings and metastatic patterns of this rare entity. We report a case of metastatic spindle cell sarcoma of the thyroid presenting with hoarseness of voice and anterior neck swelling. Subsequent fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) imaging demonstrated a fluorine-18-FDG avid mass lesion in the left lobe of the thyroid, along with FDG avid cervical lymph nodes and multiple FDG avid nodules of varying sizes in the bilateral lung fields. ¹⁸F-FDG PET/CT proved invaluable in accurately staging this rare case of metastatic high-grade sarcoma originating from the thyroid.

Background: Cardiac sarcoidosis is a challenging condition to diagnose with potentially severe consequences. Early diagnosis is crucial, but existing criteria help in diagnosis, not without limitations. This study explores the status of cardiac dyssynchrony parameters measured through gated myocardial perfusion single-photon emission computed tomography (SPECT) in diagnosing cardiac sarcoidosis.

Methods: We conducted a retrospective analytical study using data from patients who underwent cardiac inflammation imaging study (which includes myocardial perfusion SPECT and fluorodeoxyglucose positron emission tomography (FDG PET) under cardiac inflammatory protocol) between September 2018 and September 2021. The images were analyzed independently by two experienced nuclear medicine physicians. The patients were categorized as sarcoidosis positive or negative based on the Japanese Circulation Society (JCS) 2016 guidelines. Cardiac dyssynchrony parameters were assessed using phase analysis of the gated SPECT study.

Results: Among the 22 patients (11 males, 11 females), 9 were positive for cardiac sarcoidosis according to JCS 2016 criteria. Data from 9 normal control subjects were analyzed separately. The dyssynchrony parameters assessed on gated SPECT studies were significantly higher in sarcoidosis-positive patients (mean phase standard deviation [PSD] =43.05 and phase histogram bandwidth [PHB] =108.11) compared to normal control subjects (mean PSD = 19.68 and PHB = 56.22, P = 0.01). However, these parameters did not show a significant difference compared to sarcoidosis-negative patients (mean PSD = 51.13, mean PHB = 143.23, P = 0.293).

Conclusion: Cardiac dyssynchrony parameters from gated myocardial perfusion SPECT are higher in sarcoidosis patients when compared to the normal control subjects. The potential role in aiding the diagnosis of early cardiac sarcoidosis should be further investigated. To validate these findings and assess their clinical utility, further research is needed with larger sample sizes, early-stage disease, and elimination of confounding factors.