ABSTRACT
PURPOSE: The effective half-life of radioiodine is an important parameter for dosimetry in differentiated thyroid cancer patients, particularly in children. We determined the pre-therapy and post-therapy effective half-life in different types of lesions, i.e., remnant, node, or lung metastases.METHODS: Of 84 patients recruited, 27 were < 18 years (group 1) and the remaining 57 were between 18 and 21 years (group 2). A total of 114 studies were conducted and 253 lesions were analyzed. Serial whole-body scans were acquired at 24, 48, and ≥ 72 h after administration of iodine-131. Region of interests was drawn over lesions to determine counts in the lesion. Time versus counts graphs were plotted and mono-exponentially fitted to determine effective half-life.RESULTS: The post-therapy effective half-life was found to be lesser than pre-therapy effective half-life in all types of lesions and in all groups. Median effective half-life was found maximum in intact lobe, minimum in the lung, and intermediate in remnant and nodes. In the assessment of all lesions together, pre- and post-therapy median and interquartile range (IQR) effective half-life were 59.8 (37–112) h and 48.6 (35.2–70.8) h (p < 0.0001) in group 1, 73.9 (46.2–112.7) h and 60 (57.4–85.9) h (p < 0.0001) in group 2, and 68.6 (41.53–112.36) h and 54.7 (36–80.6) h (p < 0.0001) in combined group, respectively. Importantly, the pre- and post-therapy median effective half-life serially dropped after each successive cycles of iodine-131.CONCLUSIONS: There was a significant difference in pre-therapy and post-therapy effective half-life in all types of lesions. These results may have implications in calculating the correct therapeutic dose in children and in young adults.
Subject(s)
Child , Humans , Young Adult , Half-Life , Lung , Neoplasm Metastasis , Thyroid Gland , Thyroid NeoplasmsABSTRACT
PURPOSE@#The effective half-life of radioiodine is an important parameter for dosimetry in differentiated thyroid cancer patients, particularly in children. We determined the pre-therapy and post-therapy effective half-life in different types of lesions, i.e., remnant, node, or lung metastases.@*METHODS@#Of 84 patients recruited, 27 were < 18 years (group 1) and the remaining 57 were between 18 and 21 years (group 2). A total of 114 studies were conducted and 253 lesions were analyzed. Serial whole-body scans were acquired at 24, 48, and ≥ 72 h after administration of iodine-131. Region of interests was drawn over lesions to determine counts in the lesion. Time versus counts graphs were plotted and mono-exponentially fitted to determine effective half-life.@*RESULTS@#The post-therapy effective half-life was found to be lesser than pre-therapy effective half-life in all types of lesions and in all groups. Median effective half-life was found maximum in intact lobe, minimum in the lung, and intermediate in remnant and nodes. In the assessment of all lesions together, pre- and post-therapy median and interquartile range (IQR) effective half-life were 59.8 (37–112) h and 48.6 (35.2–70.8) h (p < 0.0001) in group 1, 73.9 (46.2–112.7) h and 60 (57.4–85.9) h (p < 0.0001) in group 2, and 68.6 (41.53–112.36) h and 54.7 (36–80.6) h (p < 0.0001) in combined group, respectively. Importantly, the pre- and post-therapy median effective half-life serially dropped after each successive cycles of iodine-131.@*CONCLUSIONS@#There was a significant difference in pre-therapy and post-therapy effective half-life in all types of lesions. These results may have implications in calculating the correct therapeutic dose in children and in young adults.
ABSTRACT
The histopathological approach of chronic intestinal pseudo-obstruction (CIP) is critical, and the findings are often missed by the histopathologists for lack of awareness and nonavailability of standard criteria. We aimed to describe a detailed histopathological approach for working-up cases of CIP by citing our experience. Eight suspected cases of CIP were included in the study to determine and describe an approach for reaching the histopathological diagnosis collected over a period of the last 1.5 years. The Hirschsprung's disease was put apart from the scope of this study. A detailed light microscopic analysis was performed along with special and immunohistochemical stains. Transmission electron microscopy was carried out on tissue retrieved from paraffin embedded tissue blocks. Among the eight cases, three were neonates, one in the pediatric age group, two adolescent, and two adults. After following the described critical approach, we achieved the histological diagnoses in all the cases. The causes of CIP noted were primary intestinal neuronal dysplasia (IND) type B (in 4), mesenchymopathy (in 2), lymphocytic myenteric ganglionitis (in 1), and duplication of myenteric plexus with leiomyopathy (in 1). Desmosis was noted in all of them along with other primary pathologies. One of the IND patients also had visceral myopathy, type IV. Histopathologists need to follow a systematic approach comprising of diligent histological examination and use of immunohistochemistry, immunocytochemistry, and electron microscopy in CIP workup. Therapy and prognosis vary depending on lesions identified by pathologists. These lesions can be seen in isolation or in combinations.
