Circulating thyrotropin receptor messenger ribonucleic acid is not an effective marker in the follow-up of differentiated thyroid carcinoma.

BACKGROUND: Circulating thyrotropin receptor messenger ribonucleic acid (TSHR mRNA) assay has been validated in the follow-up of differentiated thyroid carcinoma (DTC) because of its high sensitivity during thyroid hormone therapy and no interference with endogenous anti-thyroglobulin antibodies (TgAb) compared to serum thyroglobulin (Tg). We investigated the efficacy of TSHR mRNA assay in 160 DTC patients using quantitative PCR (qPCR). FINDINGS: Only TSHR mRNA level of structural persistent disease with TgAb-positive (3.47 (2.97-9.53) pg equivalents/µg total RNA; p = 0.013) and its subgroup of distant metastasis patients with TgAb-positive (5.55 (3.28-12.52) pg equivalents/µg total RNA; p = 0.009) were significantly different from patients with no evidence of disease (2.32 (1.44-3.94) pg equivalents/µg total RNA). Applying cutoff at 2.00 pg equivalents/µg total RNA enabled us to predict structural persistent disease patients with a sensitivity of 62.3 % and a specificity of 42.9 %. Although, the sensitivity of TSHR mRNA assay in TgAb-postive patients (88.2 %) was superior than serum Tg (47.1 %) (p = 0.00002), the accuracy of the test is only 54.5 %. CONCLUSIONS: This study demonstrated that TSHR mRNA assay has good sensitivity in TgAb-positive patients but it is neither specific enough as a first-line of testing nor a surrogate marker in the follow-up of our DTC patients.

Utility of Adding SPECT/CT Imaging to Post-Therapeutic Radioiodine Whole-Body Scan in Patients with Differentiated Thyroid Cancer.

OBJECTIVE: To determine the usefulness of adding single-photon emission computed tomography/computed tomography (SPECT/CT) imaging to post-therapeutic radioiodine whole-body scan (RxWBS) in patients with differentiated thyroid cancer. MATERIAL AND METHOD: RxWBSs and SPECT/CT images of 93 consecutive patients were reviewed retrospectively by three experienced nuclear medicine physicians without knowledge of clinical data. RxWBSs were reviewed first followed by evaluation of RxWBS plus SPECT/CT imaging. Foci of increased radioiodine uptake were identified and localization was attempted. The findings obtained from RxWBS were compared with WBS plus SPECT/CT imaging to determine impact on lesion characterization, TNM staging, and management plan. RESULTS: Two hundred seventy seven lesions were identified by RxWBS alone. RxWBS plus SPECT/CT imaging detected eight additional pathologic lesions (4 in bones, two in neck, and one in lung and thyroid bed). RxWBS plus SPECT/CT studies reclassified 85 of 277 lesions (30.7%) detected by RxWBS. Most change occurred in neck region (57 lesions) followed by chest region (16 lesions). For impact on TNM staging, RxWBS plus SPECT/CT studies changed N stage of 21 patients (22.6%) and reclassified M stage of 10 patients (10.8%). These resulted in change of TNM stage group of 14 patients (15.1%) and changed management plan of 19 patients (20.4%). CONCLUSION: The addition of SPECT/CT imaging to RxWBS in patients with differentiated thyroid cancer improved disease localization and lesion characterization leading to more accurate N and M staging, which was mainly downstaged. SPECT/CT also had impact on plan of management in about one fifth of the patients. However, caution should be taken when interpreting lesion in lower chest and upper abdomen because misregistration of SPECT and CT images.

The relation of vesicoureteral reflux and renal scarring in childhood urinary tract infection.

OBJECTIVE: Assess the relation of age and sex in vesico ureteral reflux (VUR) and renal scarring and the relation of VUR and renal scarring in childhood urinary tract infection. MATERIAL AND METHOD: A descriptive study of one hundred and twenty-six children who received renal cortical scintigraphy from 1st Jan 2000 to 31st Dec 2004 in the Department of Radiology, Faculty of Medicine Siriraj Hospital, was conducted. Ninety-three (50 males, 43 females) patients were diagnosed with urinary tract infections (UTIs) but only ninety-one of them had renal cortical scintigraphic results available. The male to female ratio was 1.16:1. The mean age of the patients was 4.33 years (SD +/- 4.17, range 7 days-16 years). During the 1st year of life the male to female ratio is 2.6:1. Fever, dysuria, and poor feeding were the most presenting signs and symptoms. Eighty-five (45 males, 40 females) patients received Voiding Cysto Urethro Gram (VCUG). RESULT: The authors did not find the correlation between the age groups and sex with VCUG results on right and left side, respectively (p = 0.856, p = 0.145, p = 0.77, p = 0.75). Ninety-one (49 males, 42 females) patients received DMSA renal scintigraphy. Fifty-two patients (57.1%) had abnormal DMSA renal scan results. However; the authors did not find the correlation between age groups and sex with DMSA renal scan results on the right and left kidneys, respectively. (p = 0.202, p = 0.416, p = 0.511, p = 0.791). The authors compared times of UTIs with and DMSA renal scintigraphy in each side of the kidney. Even though the authors did find the correlation between episodes of UTIs and abnormal DMSA on the left kidneys (p = 0.017), it was not found on the right kidneys (p = 0.081). There were 80 patients who received both VCUG and DMSA renal scintigraphy. The authors found the correlation between severity of VUR and abnormal DMSA results on right and left kidneys (p = 0.001, p = 0.01). CONCLUSION: The authors recommend that all children who have repeated UTI and/or VUR, irrespective of age and sex, should receive DMSA renal scintigraphy to detect renal scarring and follow up future complications.