A Rare Case of Thyroid Gland Metastasis from Laryngeal Cancer, Findings on [18F]FDG PET/CT.

Thyroid gland metastases from nonthyroidal malignancies are extremely rare. The most common primary malignancies associated with metastasis to thyroid gland include renal cell carcinoma, colorectal carcinoma, lung cancer, and breast cancer. Metastasis to thyroid rarely arises from primary laryngeal cancer. The presence of metastasis to thyroid gland is invariable and associated with poor prognosis and thus, should be differentiated from primary thyroid malignancy. Hereby, we have one such case of metastasis to thyroid gland from laryngeal cancer diagnosed on 18F-fluorodeoxyglucose positron emission tomography/computed tomography scan.

Adrenal Oncocytoma: A Rare Tumor with Conflicting Imaging Features.

Oncocytic adenomas are rare benign tumors that typically originate in organs such as the kidneys, thyroid, parathyroid, salivary glands, or pituitary gland. Oncocytic adenoma of the adrenal gland is extremely rare. It often shows heterogeneous, nonspecific features on anatomic imaging, as well as high 18F-FDG avidity despite its benign nature. The definitive diagnosis relies on histopathologic examination, including immunohistochemistry. We present an incidentally detected benign adrenal oncocytic adenoma with intense 18F-FDG uptake mimicking sinister pathologies.

Radioiodine Uptake at Suture Site Granuloma Mimicking Neck Node Metastasis on 131 I Whole-Body Iodine Scintigraphy.

ABSTRACT: Differentiated thyroid carcinoma constitutes over 90% of all thyroid cancers. The standard treatment approach involves total or near-total thyroidectomy with or without neck dissection followed by 131 I whole-body scintigraphy (WBS) to detect local or distant metastases. Radioiodine offers high sensitivity and specificity for detection of metastatic disease in well differentiated thyroid carcinoma. However, despite its high accuracy, 131 I WBS demonstrates false-positive results, mostly at inflammatory or infective site. These false-positive radioiodine accumulation can lead to misdiagnosis and unwarranted radioiodine treatment. This case presents localization of 131 I to the suture site granuloma leading to false-positive results on 131 I WBS.

Complex Regional Pain Syndrome-like Pattern in a Case of Pancoast Tumor.

We present the case of a 52-year-old male who was recently diagnosed case of a Pancoast tumor and presented to the pulmonary outpatient department with a complaint of pain in the shoulder and chest region which was burning type, associated with shoulder abduction weakness and poor hand grip. Subsequently, he was referred for a 99m-Tc bone scan for metastatic workup, which showed increased uptake in all the joints and long bones of the ipsilateral upper limb. This case highlights the importance of considering nontraumatic cause of pattern similar to complex regional pain syndrome.

Assessment of Treatment Response by Bone SPECT-CT in a Case of Dermatomyositis with Calcinosis Cutis.

Calcinosis of soft tissue is a rare but known complication of dermatomyositis (DM), mostly associated with juvenile DM and rare in adult DM. Bone scan with Tc-99m Methylene diphosphonate is useful in disease mapping and has high sensitivity to know the extent of calcinosis. However, there is scanty literature available on the utility of bone scan in treatment response evaluation in DM. Rituximab has been found useful in adult DM with calcinosis unresponsive to conventional treatment. We describe an interesting case showing partial response to rituximab on bone scan with single-photon emission tomography-computed tomography.

An Unusual Case of Glioblastoma Multiforme, Presenting as Skeletal Superscan.

Extracranial metastases of glioblastoma multiforme (GBM) are very rare. The estimated incidence is <2%. We report a case of a 49-year-old woman, who was a known case of GBM in the left temporo-occipital lobe. She was operated and had received radiotherapy and adjuvant chemotherapy for the same. Subsequently, the patient underwent bone scan. On 99 m-Tc methylene diphosphonate (MDP) bone scan, homogenously increased tracer uptake was noted in the axial and appendicular skeletal system, suggesting metastatic skeletal superscan.

Management of Ectopic Thyroid in Head and Neck: Study of 8 Cases.

INTRODUCTION: To analyze the clinical features, diagnosis, management and clinical outcomes in the patients with ectopic thyroid in a tertiary care hospital. MATERIALS AND METHODS: This was a retrospective study which included eight cases of ectopic thyroid presented in the outpatient clinic. Their medical records were reviewed for clinical presentation, imaging modalities used, biochemical tests and outcomes of the management was analyzed. RESULTS: Total eight patients were included in the study, of which five were females and three were males, within the age range of 6 - 44 years. Painless neck swelling was the predominant complaint, which was observed in the seven (87.50%) patients. Total 6 (75%) patients had normal thyroid function test and 2 (25%) patients had features of hypothyroidism. Three patients underwent surgery and three patients needed hormonal replacement. Follow-up was advised for three patients. Post-treatment follow-up of all the patients was conducted for 24 months and no significant progression/recurrence/malignant transformation of the disease was seen in any of the patients. CONCLUSION: Being a rare disorder, timely diagnosis and management is important to avoid complications and for better clinical outcomes.

Comparison of bone SPECT/CT and MRI in detection of pain generator in ankle and foot pain: a retrospective diagnostic study.

OBJECTIVE: To study the sensitivity and specificity of MRI and bone SPECT-CT in detecting the pain generator in ankle and foot pain with diagnostic dilemma. METHODS: Retrospectively data of patients with ankle or foot pain who underwent both MRI and Bone SPECT-CT were analyzed. The lesions and probable pain generator sites were reported as per MRI and bone SPECT-CT findings. These lesions were correlated clinically, managed accordingly and followed up. The patients who had significant improvement in response to the treatment provided were considered to have been diagnosed accurately. The foot and ankle disability index (FADI) was used to evaluate the patient's pre- and postintervention condition. RESULTS: The study included 37 patients retrospectively (18 women and 19 men). The lesions were classified into soft tissue lesions (ligaments/tendons), joint lesions (arthritis) and bony lesions (fractures/osteomyelitis/osteochondral lesions). Overall, MRI had sensitivity, specificity, positive predictive value and negative predictive value of 82, 31, 74 and 42%, respectively, and SPECT-CT had sensitivity, specificity, positive predictive value and negative predictive value of 84, 60, 84 and 60%, respectively. The mean FADI score pretreatment for all patients was 61.5 (SD = 13.8) and posttreatment 88.4 (SD = 13.01) showing significant improvement in the score (P < 0.05), suggesting that the final diagnosis of these patients was accurate. Overall, management change due to bone SPECT-CT over MRI was seen in 26% of patients. CONCLUSION: Bone SPECT-CT has incremental value over MRI in the diagnosis of pain generator in foot and ankle pain. The overall specificity of bone SPECT-CT is higher than MRI in detection of pain generators. Bone SPECT-CT performed better than MRI in detection of culprit pathology in the bone, whereas MRI is better in soft tissue lesions. ADVANCES IN KNOWLEDGE: There are only a few published literature with direct comparison of bone SPECT-CT scintigraphy and MRI in detection of foot and ankle pain generator. This study directly compares diagnostic utility of bone SPECT-CT scintigraphy and MRI in foot and ankle pain. In the present study, the bone SPECT-CT performed better than MRI in detection of culprit pathology in the bone, whereas MRI is better in soft tissue lesions.

Prevalence of Marine-Lenhart syndrome on 99mTc-thyroid scintigraphy and response to radioiodine: A single institutional retrospective study.

Marine-Lenhart Syndrome is a rare entity, described as Graves' disease with coexisting functioning thyroid nodules. It is often diagnosed on thyroid scintigraphy as a cold nodule with surrounding extranodular hyperactivity initially and postradioiodine ablation, they regain function on the follow-up thyroid scintigraphy due to endogenous thyroid-stimulating hormone (TSH) stimulation. We retrospectively reviewed all thyroid scintigraphy database performed between January 2018 and March 2020 in our institute. We searched patients with Graves' disease with the following criteria to suggest Marine-Lenhart Syndrome: (a) initial thyroid scintigraphy showing features of Graves' disease with coexistent poorly functioning nodules (b) There is normalization of uptake within the nodule on thyroid scan after radioiodine ablation suggestive of endogenous TSH stimulation (this also indirectly proves nodules are TSH dependent), (c) nodule(s) is/are benign on fine-needle aspiration cytology. Four patients (1.46%) were confirmed as Marine-Lenhart Syndrome as per the criteria. Three patients were female, and one was male. The eye signs were present in two of four patients. Two patients had two hypofunctioning nodules, whereas the remaining two had a single nodule and required re-ablation with radioiodine. Marine-Lenhart Syndrome requires special attention as these patients are relatively radioiodine resistant, require higher activity for iodine-131; however, it is curable with radioiodine treatment.

Tc-99m HYNIC-TOC scintigraphy in dedifferentiated thyroid cancer.

There is literature evidence showing utility of somatostatin receptor (SSTR) positron emission tomography-CT (PET-CT) imaging in differentiated thyroid cancer with Thyroglobulin Elevated and Negative Iodine Scan (TENIS). These patients are less benefited with I-131 therapy and surgery remains only curable option if disease could be localised. If surgery is not feasible, other therapeutic options are not promising. However, if these patients show strongly positive SSTR imaging, then possibility of peptide receptor radionuclide therapy may be explored. As SSTR PET-CT imaging is expensive and not widely available, Technetium-99m (Tc-99m) hydrazinonicotinyl-Tyr3-octreotide (HYNIC-TOC), which is a Single photon emission computed tomography (SPECT) tracer, can be used. We are documenting a case of raised serum thyroglobulin antibody and negative I-131 whole body scan with disease recurrence localised on Tc-99m HYNIC-TOC scan.

Triple Ectopic Thyroid Detected on SPECT/CT: A Rare Case Report.

Ectopic thyroid tissue is a rare entity of embryological aberration along the tract of descend of thyroid gland. Accurate localization and characterization are required for deciding management based on clinical features and symptoms. Ectopic thyroid in the absence of normal thyroid gland is uncommon. However, triple ectopic thyroid with absence of normal thyroid gland is very rare, with only a few cases reported previously. We present a case of triple ectopic thyroid, which appeared as single on planar Tc-sodium pertechnetate image, but was evident on SPECT/CT images.