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Oncology 2023Therapy-related leukemia is a term that describes the occurrence of leukemia following exposure to hematotoxins and radiation to emphasize the difference from leukemia... (Review)
Review
BACKGROUND
Therapy-related leukemia is a term that describes the occurrence of leukemia following exposure to hematotoxins and radiation to emphasize the difference from leukemia that arises de novo. Many agents and host factors contribute to this entity of leukemias. Therapy-related acute myeloid leukemia has an extensive literature review in contrast to therapy-related chronic myeloid leukemia (t-CML). Radioactive iodine (RAI), an established agent in the management of differentiated thyroid carcinomas, has raised concern due to its possible carcinogenic effects.
SUMMARY
In this article, we reviewed all the reports from the 1960s to date related to t-CML following RAI on Google Scholar and PubMed. We have identified 14 reports and found that most reports were for men under the age of 60 years with primary papillary thyroid carcinoma and mixed follicular-papillary thyroid carcinoma who developed t-CML mainly between 4 and 7 years after exposure to varying doses of I131. However, the mean dose was 287.78 millicuries (mCi). It was reported that a statistically significant increase in leukemia following RAI therapy (relative risk of 2.5 for I131 vs. no I131). Also, there was a linear relationship between the cumulative dose of I131 and the risk of leukemia. Doses higher than 100 mCi were associated with a greater risk of developing secondary leukemia, and most of the leukemias developed within the initial 10 years of exposure. The precise mechanism through which RAI provokes leukemia is largely unclear. A few mechanisms have been proposed.
KEY MESSAGES
Although the risk for t-CML appears to be low based on current reports and does not represent a contraindication to RAI therapy, it should not be disregarded. We suggest including it in the risk-benefit discussion before initiating this therapy. Long-term follow-up for patients is advisable for those who received doses over 100 mCi with a complete blood count, possibly yearly, for the first 10 years. The new onset of significant leukocytosis post RAI exposure should raise the suspicion for t-CML. Further studies are needed to establish or refute a causal relationship.
Topics: Male; Humans; Middle Aged; Thyroid Neoplasms; Iodine Radioisotopes; Thyroid Cancer, Papillary; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Risk Assessment
PubMed: 37231874
DOI: 10.1159/000530463 -
Journal of Nuclear Medicine : Official... Jan 2005Tositumomab and (131)I-tositumomab constitute a relatively new radioimmunotherapeutic regimen for patients with CD20+ follicular non-Hodgkin's lymphoma (NHL). Currently,... (Review)
Review
UNLABELLED
Tositumomab and (131)I-tositumomab constitute a relatively new radioimmunotherapeutic regimen for patients with CD20+ follicular non-Hodgkin's lymphoma (NHL). Currently, it is approved for use in patients whose disease has relapsed after chemotherapy and is refactory to rituximab, including patients whose tumors have transformed to a higher histologic grade. This review outlines the current and evolving status of this therapeutic regimen at nonmyeloablative doses.
METHODS
Clinical data from multiple published studies and preliminary communications encompassing more than 1,000 patients were reviewed to describe the current status of tositumomab and (131)I-tositumomab therapy. The therapy is delivered in 2 parts, a dosimetric dose and a therapeutic dose. The therapeutic radioactivity millicurie dose is calculated on a patient-individualized ("tailored") basis. A series of 3 total-body gamma-camera scans are used to determine the patient-specific pharmacokinetics (total-body residence time) of the radiolabeled antibody conjugate required to deliver the desired total-body radiation dose, typically 75 cGy.
RESULTS
In clinical trials, objective response rates in patients who had been extensively pretreated with chemotherapy ranged from 47% to 68%. Tositumomab and (131)I-tositumomab therapy also was effective in patients who had failed to respond to or who had relapsed after rituximab therapy, with a 68% overall response rate. Thirty percent of such patients achieved complete responses that were generally of several years duration. Single-center trials using tositumomab and (131)I-tositumomab therapy alone or after chemotherapy in previously untreated patients have shown response rates in excess of 90%, with most responses complete. Retreatment with tositumomab and (131)I-tositumomab and use of lower total-body radiation doses of tositumomab and (131)I-tositumomab to treat patients who have relapsed after stem cell transplantation have been shown feasible in limited clinical studies. Toxicity is predominately hematologic; however, human antimouse antibodies, hypothyroidism, and myelodysplastic syndrome have been reported in a small fraction of patients.
CONCLUSION
Tositumomab and (131)I-tositumomab therapy at patient-specific, nonmyeloablative doses is safe and effective in treatment of relapsed and refractory follicular NHL. Toxicity is mainly hematologic and reversible. Tositumomab and (131)I-tositumomab therapy is assuming a growing role in this common malignancy.
Topics: Animals; Antibodies, Monoclonal; Clinical Trials as Topic; Humans; Immunotherapy; Lymphoma, Non-Hodgkin; Practice Guidelines as Topic; Practice Patterns, Physicians'; Radioimmunotherapy; Treatment Outcome
PubMed: 15653661
DOI: No ID Found -
The Journal of General Physiology Mar 1922It has been estimated that 92 per cent of the total radiation emitted by radium in equilibrium with its subsequent products is given off in the form of alpha-rays. This,...
It has been estimated that 92 per cent of the total radiation emitted by radium in equilibrium with its subsequent products is given off in the form of alpha-rays. This, however, cannot be utilized when the source is enclosed in an ordinary container, because the alpha-rays are absorbed completely by even a small thickness of glass. About 3.2 per cent of the total radiation is emitted in the form of beta-rays, and 4.8 per cent as gamma radiation. The effects produced on the radiated mice of these experiments were due mainly to the beta-rays, which are easily absorbed by tissue. The gamma-rays, being only slightly absorbed by organic matter, probably contributed very little to the observed effects. It is interesting to correlate the different effects produced by the same dose of radiation. The mice which received a dose of 1.9 millicurie hours showed no local effects on the skin or hair. Neither females nor males were sterilized, and the time at which they opened their eyes or reached sexual maturity was not affected, as far as we could tell. The only difference noted between the radiated animals and the controls was in the body weight. This dose accelerated the growth of the young mice, that is, while initially of the same weight, soon after irradiation they became distinctly bigger than the controls, but finally the animals of each group had substantially the same average weight. That this variation in body weight should be accidental is unlikely, since it was observed also in the animals treated by a slightly larger dose (2.4 millicurie hours). The number of animals (seven) which showed this effect is too small to prove conclusively the accelerating effect of small doses of radiation on the body growth of mice. But considering that similar results have been. obtained by radiating plants and beetles, it is reasonable that the observed increase in weight might be attributed, at least in part, to the effects of radiation. Since this paper was first written Russ, Chambers, and Scott have shown that small doses of x-rays accelerate the body growth of rats. In view of this additional evidence there can be little doubt that the increase in weight observed in our experiments was due to the radiation. A dose of 2.4 millicurie hours applied over the backs of the animals produced no local skin effects, but it accelerated the growth of the mice as in the previous case. In addition it caused permanent sterilization of all the females. A similar result was obtained with 4.9 millicurie hours, except that the effect on the rate of growth was uncertain. A dose of 6.8 millicurie hours produced a definite but mild skin erythema and retarded the development of lanugo hair. But since in this instance the emanation was applied over the heads of the animals, the dose reaching the ovaries was not sufficient to cause sterilization, as already explained. No other definite effect was noted. In connection with the sterilization of the females it should be noted that a dose of radiation which produced no visible skin changes was sufficient to cause permanent sterility. On account of the greater distance of the ovaries from the source of radiation as compared with that of the skin directly below the tube, and the depth of tissue which the rays had to traverse to reach the ovaries, the amount of radiation acting on the latter was much smaller than the amount falling on the skin. The radiation emitted by the emanation tube is reduced to about 50 per cent of its initial value after traversing 1 mm. of tissue. Still, while the skin was not visibly affected, the mice were sterilized. This shows that the ovaries are influenced very easily by radiation of this type. We can estimate the amount of radiation reaching the ovaries which is sufficient to cause sterility to be less than 25 per cent of the amount necessary to produce visible skin changes in the mice. It should be noted also that whenever sterility of the female mice was induced, it was permanent. Furthermore, those mice which were not rendered sterile by radiation were, as far as the experiments enable us to say, as prolific as the controls. Remembering that a dose of 1.9 millicurie hours had no apparent effect on the ovaries, while a slightly larger dose, 2.4 millicurie hours, caused permanent sterility, it might be concluded that it is not possible to produce temporary sterility by radiation. We know, however, that temporary sterility can be produced, at least when the animals are radiated at a later stage in their development. The mice in our experiments were radiated for the first time soon after birth, and it is not improbable that under these conditions temporary sterility cannot be obtained. Large sublethal doses produced severe skin burns, retarded the body growth of the animals, but failed to sterilize the males. About one-third of the total skin area of the mice showed marked effects from the radiation. The animals were very sick for a time, and their growth was temporarily stunted. But nevertheless they recovered and finally became apparently normal except for the narrow hairless strip of skin which had been closest to the emanation tube. Only the females were rendered permanently sterile. The males did not show even temporary sterility when the doses of radiation were close to the lethal dose. While the testes of mammals are known to be very easily affected by radiation, still they are more resistant than the ovaries. In addition, in these experiments they were at a greater distance from the source of radiation than the ovaries, and they were better protected by the thicker layer of tissue in the path of the rays. The fact that no sublethal dose in these experiments sterilized the males shows that under the conditions of irradiation adopted the amount of radiation reaching the testes was not sufficient to affect them noticeably. If the source of radiation had been applied closer to the reproductive organs of the males, they would have been sterilized by millicurie hour doses much smaller than the lethal dose. Some of the radiated animals were killed with ether, and macroscopic and microscopic examinations of the reproductive organs were made. The ovaries of the sterile females were generally atrophied and colored yellow. The normal histological structure was altered. The characteristic findings were the destruction of the Graafian follicles, with absence of ovum cells. The testes and the epididymis of the radiated mice of the present experiment appeared macroscopically and histologically normal, with the presence of abundant spermatozoa. Owing to the method adopted for the irradiation of the mice, the testes were too far from the source of radiation, and too well protected by the intervening tissue to be definitely affected by the rays.
PubMed: 19871946
DOI: 10.1085/jgp.4.4.423 -
Journal of Veterinary Internal Medicine Mar 2017Radioiodine ( I) is effective treatment for hyperthyroidism in cats, but optimal dose to restore euthyroidism without inducing hypothyroidism is unclear....
BACKGROUND
Radioiodine ( I) is effective treatment for hyperthyroidism in cats, but optimal dose to restore euthyroidism without inducing hypothyroidism is unclear. Treatment-induced hypothyroidism can lead to azotemia and reduced duration of survival.
OBJECTIVE
To compare efficacy and short-term outcomes of low-dose I versus higher, standard-dose I as treatment for hyperthyroidism.
ANIMALS
A total of 189 client-owned cats undergoing I treatment for mild-to-moderate hyperthyroidism (serum T ≥ 4.0 μg/dL and <13.0 μg/dL).
METHODS
Prospective, nonrandomized, cohort study comparing treatment with either low-dose (2 mCi, n = 150) or standard-dose (4 mCi, n = 39) I. Serum T , thyroid-stimulating hormone (TSH), and creatinine concentrations were measured after 1, 3, and 6 months to determine persistent hyperthyroidism, overt hypothyroidism (low T , high TSH), subclinical hypothyroidism (normal T , high TSH), and azotemia.
RESULTS
There was no significant difference in prevalence of cats with persistent hyperthyroidism between standard- and low-dose treatment groups at 3 (0% versus 5.3%; P = .34) and 6 (0% versus 3.3%; P = .51) months. Overt (18% versus 1%; P = .0005) or subclinical (46% versus 21%; P = .004) hypothyroidism was more common in cats at 6 months after standard-dose I. No difference in incidence of azotemia existed between groups, but cats treated with standard-dose I had higher creatinine concentrations (P < .05) and higher percent rises in creatinine (P < .0001).
CONCLUSIONS AND CLINICAL IMPORTANCE
Low-dose I is safe and effective for cats with mild-to-moderate hyperthyroidism, as evidenced by a cure rate of >95% with reduced frequency of iatrogenic hypothyroidism and azotemia.
Topics: Animals; Azotemia; Cat Diseases; Cats; Creatinine; Female; Hyperthyroidism; Hypothyroidism; Iodine Radioisotopes; Male; Prospective Studies; Thyrotropin; Thyroxine; Treatment Outcome
PubMed: 28158908
DOI: 10.1111/jvim.14646 -
Indian Journal of Surgical Oncology Mar 2022The real-world patterns of TKI use in differentiated thyroid cancer (DTC) are largely governed by the accessibility and financial feasibility of the patient with more...
The real-world patterns of TKI use in differentiated thyroid cancer (DTC) are largely governed by the accessibility and financial feasibility of the patient with more sorafenib use compared to lenvatinib. There are limited data available on the toxicity profile, safety and tolerance of sorafenib and lenvatinib in DTC. Hence, we audited our practice on DTC. This is a retrospective single-centre analysis of patients with DTC who were referred to the Department of Medical Oncology for systemic therapy. Baseline demographics (age, sex, ECOG PS, comorbidities, substance use), tumour details (site of metastasis), previous treatment details, clinical features at metastasis (symptoms), the pattern of treatment, adverse events and outcomes including progression and death were extracted. There were 67 patients with DTC referred for systemic therapy; the median age was 56 (33-81) with a male preponderance (55.6%). The most common reason to start TKI therapy was radioactive iodine (RAI) cumulative dose > 600 milliCurie, followed by low iodine uptake in the RAI low-dose scan done at progression. The most common TKI used in the first line was sorafenib in 56 (83.6%) patients followed by lenvatinib in 9 (13.4%) patients. Papillary thyroid carcinoma was the most common histology (51, 76.1%), and the rest were follicular carcinoma (16, 23.9%). With a median follow-up of 36 months, the median PFS was 13.2 months (95% CI 10.4-16.0). The median OS was 18.8 months (95% CI 10.0-27.6). Among variables tested, no factors had a significant impact on the PFS or OS. The most common adverse events were hand-foot syndrome (54, 80.5%), diarrhoea (23, 33.3%) and transaminitis (24, 34.4%). The pattern of care of patients with RAI-refractory DTC is TKI therapy, especially sorafenib and lenvatinib in the real-world settings with comparable efficacy and safety profile compared to international literature.
PubMed: 35462674
DOI: 10.1007/s13193-021-01445-y -
Journal of Nuclear Medicine : Official... Aug 2003Radionuclide therapy remains a promising arsenal against cancer. However, low tumor uptake, high radiation dose to normal organs, and subsequent adverse effects are... (Comparative Study)
Comparative Study
UNLABELLED
Radionuclide therapy remains a promising arsenal against cancer. However, low tumor uptake, high radiation dose to normal organs, and subsequent adverse effects are challenging problems. This study assessed the therapeutic significance of lipid-soluble compounds of (111)In, which passively diffuse through the cell membrane, bind to cytoplasmic components, and remain cell bound until decay.
METHODS
Athymic nude mice bearing human colorectal, prostate, or breast cancer received 11.1-14.8 MBq (300-400 micro Ci) (111)In-8-hydroxyquinoline ((111)In-oxine) or (111)In-mercaptopyridine-N-oxide ((111)In-Merc) in 200 micro L solution intratumorally through a multihole needle. Tumors in some mice were dissected, and 20- micro m-thick sections were autoradiographed. In additional mice, tumor diameter was measured daily, mice were imaged and weighed, and blood samples were drawn for determination of neutrophil counts for up to 28 d after injection. Some mice were sacrificed at predetermined times for quantitative tissue distribution of (111)In. Additionally, tumor cells were labeled with (111)In-oxine and homogenized, and (111)In associated with cell components was determined using polyacrylamide gel electrophoresis. Radiation dose that could be delivered to adjacent tissues was estimated. The (111)In absorbed dose as a function of radial position r in a 1-g tumor was theoretically compared with those of beta-emitting radionuclides (90)Y and (177)Lu.
RESULTS
More than 85% of (111)In remained in tumors, bound to cell cytoplasmic components of apparent molecular weights 250 and 6 kDa. (111)In in tumors was uniformly distributed. Only 2% of the injected (111)In was in the liver, kidneys, and carcass. Statistical analysis showed that on day 28, control tumors grew >100%, whereas treated tumors either had growth arrest or grew only slowly (17%). The estimated radiation dose per megabecquerel (millicurie) injected was 90 Gy/g (9,000 rad/g), of which 64% was from conversion electrons, 16% from Auger electrons, 20% from gamma-photons and x-rays, respectively. Radiation dose to adjacent normal organs was 5%-10% of the radiation dose to the tumor and negligible to the liver and kidneys. Neutrophil counts remained unchanged. Mouse body weight was +/-10% of the initial weight. The radiation dosimetry for (111)In and (177)Lu compared favorably, but not that of (90)Y.
CONCLUSION
Treatment is independent of receptor density, heterogeneity, or the hypoxic status of cells. It is applicable to treat all known and accessible tumor types, and it delivers a negligible radiation dose to vital organs and only 5%-10% of the radiation dose to organs adjacent to the tumor. Intratumoral administration of (111)In-oxine appears to be a feasible, effective, safe, and promising treatment for cancer.
Topics: Animals; Breast Neoplasms; Cell Line; Colorectal Neoplasms; Dose-Response Relationship, Radiation; Drug Delivery Systems; Feasibility Studies; Humans; Injections, Intralesional; Lipids; Male; Mice; Mice, Nude; Neoplasms; Organometallic Compounds; Oxyquinoline; Prostatic Neoplasms; Pyridines; Radionuclide Imaging; Radiopharmaceuticals; Radiotherapy Dosage; Solubility; Thiones; Treatment Outcome; Tumor Cells, Cultured
PubMed: 12902421
DOI: No ID Found -
Blood Feb 2018Pretargeted radioimmunotherapy (PRIT) has demonstrated remarkable efficacy targeting tumor antigens, but immunogenicity and endogenous biotin blocking may limit clinical...
Pretargeted radioimmunotherapy (PRIT) has demonstrated remarkable efficacy targeting tumor antigens, but immunogenicity and endogenous biotin blocking may limit clinical translation. We describe a new PRIT approach for the treatment of multiple myeloma (MM) and other B-cell malignancies, for which we developed an anti-CD38-bispecific fusion protein that eliminates endogenous biotin interference and immunogenic elements. In murine xenograft models of MM and non-Hodgkin lymphoma (NHL), the CD38-bispecific construct demonstrated excellent blood clearance and tumor targeting. Dosimetry calculations showed a tumor-absorbed dose of 43.8 Gy per millicurie injected dose of Y, with tumor-to-normal organ dose ratios of 7:1 for liver and 15:1 for lung and kidney. In therapy studies, CD38-bispecific PRIT resulted in 100% complete remissions by day 12 in MM and NHL xenograft models, ultimately curing 80% of mice at optimal doses. In direct comparisons, efficacy of the CD38 bispecific proved equal or superior to streptavidin (SA)-biotin-based CD38-SA PRIT. Each approach cured at least 75% of mice at the highest radiation dose tested (1200 µCi), whereas at 600- and 1000-µCi doses, the bispecific outperformed the SA approach, curing 35% more mice overall ( < .004). The high efficacy of bispecific PRIT, combined with its reduced risk of immunogenicity and endogenous biotin interference, make the CD38 bispecific an attractive candidate for clinical translation. Critically, CD38 PRIT may benefit patients with unresponsive, high-risk disease because refractory disease typically retains radiation sensitivity. We posit that PRIT might not only prolong survival, but possibly cure MM and treatment-refractory NHL patients.
Topics: ADP-ribosyl Cyclase 1; Animals; Antibodies, Bispecific; CHO Cells; Cell Line, Tumor; Cricetinae; Cricetulus; Female; Humans; Leukemia, B-Cell; Lymphoma, B-Cell; Mice, Nude; Molecular Targeted Therapy; Multiple Myeloma; Radioimmunotherapy; Xenograft Model Antitumor Assays
PubMed: 29158362
DOI: 10.1182/blood-2017-09-807610 -
Journal of Nuclear Medicine : Official... Aug 1990Ten patients with non-Hodgkin's lymphoma have been evaluated as candidates for experimental radioimmunotherapy and five of those patients have been treated with a single...
Ten patients with non-Hodgkin's lymphoma have been evaluated as candidates for experimental radioimmunotherapy and five of those patients have been treated with a single high dose of iodine-131-(131I) labeled anti-pan B-cell antibodies. The evaluation protocol involved collecting biodistribution data by quantitation of gamma camera images and by tumor biopsy from trace labeled doses of antibody, to estimate the relative radiation dose delivered to normal organs and tumor sites. Each patient received up to three escalating mass doses (0.5 mg/kg, 2.5 mg/kg, and 10.0 mg/kg) of radioiodinated antibody for determination of the antibody amount that yielded the most favorable biodistribution for treatment. The millicuries of 131I-labeled to the optimal antibody dose for therapy was selected to deliver 1,000 rads (three patients) or 1,500 rads (two patients) to normal uninvolved organs. Because severe bone marrow toxicity was expected, all patients had their bone marrow cryopreserved prior to entry into the study. This report details the methods and results of quantitative imaging, biodistribution data collection, and absorbed radiation dose estimation in patients with lymphoma receiving high level radioimmunotherapy with 131I-labeled antibodies.
Topics: Antibodies, Monoclonal; B-Lymphocytes; Combined Modality Therapy; Humans; Immunotherapy; Iodine Radioisotopes; Lymphoma, Non-Hodgkin; Radionuclide Imaging; Tissue Distribution
PubMed: 2384792
DOI: No ID Found -
Journal of Veterinary Internal Medicine Nov 2018Radioiodine is the treatment of choice for hyperthyroidism in cats. The ideal method of dose determination of radioiodine remains controversial.
BACKGROUND
Radioiodine is the treatment of choice for hyperthyroidism in cats. The ideal method of dose determination of radioiodine remains controversial.
OBJECTIVE
To compare a method of radioiodine dose determination that utilized thyroid scintigraphy with a standard fixed dose for treatment of hyperthyroidism.
ANIMALS
Fifty-seven and 23 client-owned hyperthyroid cats in the variable and fixed dose groups, respectively.
METHODS
Cats with a percent dose uptake using Tc-pertechnetate uptake on thyroid scintigraphy <5%, 5%-10%, and >10% were to receive 3, 3.5, or 4.5 millicuries (mCi) of radioiodine, respectively, administered SC. Radioiodine dose was adjusted according to thyroid gland size as determined by the thyroid:salivary size ratio and categorized as <5:1, 5-10:1, and >10:1. If the thyroid size fell into a higher dosing category than the percent dose uptake, the dose was increased accordingly. Cats in the fixed dose group received 4.5 mCi. Six months after treatment, cats were determined to be euthyroid, hypothyroid, or hyperthyroid based on serum thyroxine and thyroid stimulating hormone concentrations.
RESULTS
No difference in outcome was found between the variable and fixed dose treatment groups. Euthyroidism, hypothyroidism, and persistent hyperthyroidism developed in 61, 30, and 9% of cats in the fixed dose group compared to 58, 26, and 16%, respectively, in the variable dose group.
CONCLUSIONS
A variable dosing method of radioiodine based on percent dose uptake primarily and thyroid gland size secondarily did not improve outcome compared to a standard fixed dose method.
Topics: Animals; Cat Diseases; Cats; Drug Dosage Calculations; Female; Hyperthyroidism; Iodine Radioisotopes; Male; Treatment Outcome
PubMed: 30328158
DOI: 10.1111/jvim.15296 -
AACE Clinical Case Reports 2019The objective of this report is to present an unusual case of intramedullary spinal cord metastasis (ISCM) as the presenting feature of papillary thyroid carcinoma (PTC).
OBJECTIVE
The objective of this report is to present an unusual case of intramedullary spinal cord metastasis (ISCM) as the presenting feature of papillary thyroid carcinoma (PTC).
METHODS
The presented case includes clinical, biochemical, and imaging findings as well as surgical and pathology reports. Treatment with radioactive iodine (RAI) and the response to this treatment are presented.
RESULTS
A 71-year-old woman was evaluated for debilitating low back pain and walking disability. Magnetic resonance imaging demonstrated an oval, lumbar, intramedullary mass with benign features and surgery was scheduled. On preoperative evaluation for the lumbar mass, a multinodular thyroid goiter (unfortunately overlooked previously) was noticed, causing severe narrowing of the trachea. Total thyroidectomy was performed with a pathology diagnosis of PTC. In a second operation, the lumbar lesion was removed and proved to represent metastatic PTC. External beam radiation was subsequently administered to the thyroid bed, lumbar spine, and other skeletal metastases, followed by 150 milliCurie of RAI. A post-treatment scan showed high uptake over the lumbar spine, and skeletal and lung lesions. Clinically, the patient restored her walking ability and back pain improved.
CONCLUSION
ISCM rarely is the presenting feature of PTC. Our patient presented with back pain which is the typical, though non-specific symptom, of ISCM. She showed good clinical response to multimodal treatment which is in line with the few other differentiated thyroid cancer patients with ISCM reported in the literature. Prompt surgical resection, followed by external beam radiation and RAI, may improve neurological signs, alleviate pain, and improve quality of life.
PubMed: 31967051
DOI: 10.4158/ACCR-2019-0072