Hematologic toxicity is the most common adverse effect leading to treatment delay or early discontinuation of [¹⁷⁷Lu]Lu-DOTA-TATE peptide receptor radionuclide therapy (PRRT). We evaluated baseline clinical, laboratory, and quantitative somatostatin receptor (SSTR)-PET parameters as predictors of hematologic toxicity in gastroenteropancreatic neuroendocrine tumors (GEP-NETs), focusing on whether imaging adds value beyond routinely available clinical and laboratory data. In this two-center retrospective study, 96 patients treated with 1–4 cycles of [¹⁷⁷Lu]Lu-DOTA-TATE PRRT were analyzed. Hematologic toxicity was defined as CTCAE grade aggravation from baseline using nadir complete blood count (CBC) values. Baseline clinical, hematologic, and [⁶⁸Ga]Ga-DOTA-TOC PET parameters were evaluated using univariable analyses, followed by multivariable logistic regression for grade ≥ 3 hematologic toxicity. Grade ≥ 3 hematologic toxicity affecting at least one hematologic parameter occurred in 20 patients (20.8
F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) is an established imaging modality for thoracic imaging, including characterisation of solitary pulmonary nodules, staging of lung carcinoma, radiotherapy planning, and guiding biopsy site selection in thoracic lesions. In routine practice, many benign and malignant thoracic neoplasms may be detected on PET/CT imaging performed for other indications. Accurate characterisation and reporting of such lesions require knowledge of their expected PET and CT findings. This review highlights the PET/CT findings of various benign and malignant tumours of the thorax.
Low-dose photon irradiation has been reported to modulate inflammatory responses. Technetium-99m (99mTc), a widely used diagnostic radionuclide emitting low-energy gamma photons, provides a model for exploring potential anti-inflammatory responses associated with localized radionuclide exposure. Dermatitis was induced in BALB/c mice using 2,4-dinitrochlorobenzene. Mice were treated with localized [99mTc]pertechnetate patches at activities of 37, 111, or 222 MBq, topical hydrocortisone, or no treatment. Clinical severity, histopathological changes, and immunohistochemical IL-6 and TNF-α expression were evaluated. Local absorbed photon doses were estimated using a simplified point-kernel photon-fluence model. Overall between-group differences were statistically significant for all four endpoints, but no pairwise comparison remained significant after exact testing with Holm adjustment. Descriptively, 37 MBq had the lowest median histopathological and IL-6 scores, 111 MBq the lowest median clinical severity score, and hydrocortisone the lowest median TNF-α score, followed by 37 MBq. The 222 MBq group showed no consistent descriptive advantage. Estimated absorbed doses were 0.21, 0.64, and 1.28 Gy for 37, 111, and 222 MBq, respectively. Localized [99mTc]pertechnetate exposure showed endpoint-dependent immunomodulatory trends in a murine dermatitis model, although statistically significant treatment effects were not established by adjusted pairwise comparisons. This study explored the biological effects of localized radionuclide exposure rather than its use as a therapeutic strategy for dermatitis. Given the small sample size and simplified dosimetry, these exploratory findings are compatible with radiation-associated immunomodulation but do not establish therapeutic efficacy. Further studies are warranted to confirm these observations and evaluate their translational relevance.
