Metallosis is a medical condition that shows local and systemic clinical symptoms due to the deposition of heavy metal debris in soft tissues and bones due to metallic prostheses. The estimated incidence of Metallosis is around 5%. Clinical presentation and imaging findings can mimic tumor likely situation, However local reactions of Metallosis shows some peculiar features on cross-sectional imaging, and here we present two such cases of Metallosis with its imaging findings.

Marginal zone lymphoma (MZL) is a group of low-grade, indolent, non-Hodgkin lymphomas rarely manifesting in the lungs. A 46-year-old man presenting with shortness of breath and cough was investigated and treated over 10 months for an atypical pattern of lung disease in keeping with cryptogenic organizing pneumonia (COP). Initial lung biopsies were nondiagnostic - repeat sampling eventually showed MZL. Staging whole-body (18F) fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) demonstrated multisystem stage IV disease with intensely avid widespread pulmonary changes resembling COP. The case elegantly illustrates that pulmonary MZL can present insidiously masquerading as COP and shows the value of (18F) FDG PET/CT to stage extranodal MZL.

A 42-year-old male presented with a dry cough, breathlessness, and fever. He underwent a computed tomography that revealed large consolidation in the right lung. Biopsy revealed Cryptococcus neoformans. He was on antifungal for 4 months with no clinicoradiological improvement. 18F- fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) showed consolidations in the right lung with multiple lung nodules. 18F-FDG PET/CT ascertains the diagnosis of residual fungal infection and rules out extrapulmonary involvement.

The purpose of this study was to evaluate the utility of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FPCT) parameters for detecting recurrent disease and the outcomes of salvage surgery in patients with locally advanced oral tongue squamous cell carcinoma (TSCC) after multimodal treatment. In total, 69 patients with locally advanced TSCC were treated with multimodal therapy. All patients underwent whole-body FPCT scans 4-10 months after the initial surgery. The analysis included FPCT parameters, such as maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG). Histological examination was used as the reference standard. Patients with recurrent TSCC underwent salvage surgery or surgery plus systemic treatment. This study included 69 patients: 36 in the recurrent TSCC group and 33 in the non-recurrent TSCC group. The SUVmax, MTV, and TLG in the recurrent TSCC group were 11.3 ± 3.6, 28.3 ± 15.6 cm3, and 113.2 ± 46.8 g, respectively; these values were 5.9 ± 3.6, 5.1 ± 2.2 cm3, and 13.4 ± 4.8 g, in the non-recurrent TSCC group respectively. The two groups had significant differences in terms of SUVmax, MTV, and TLG. In the recurrent TSCC group, 91.6 % of patients presented with local, locoregional, and regional disease and underwent salvage surgery plus systemic therapy, whereas 8.4 % had locoregional recurrence with distant metastases alone and underwent surgery plus systemic therapy. The patients were followed up for 12-60 months; 19 and 20 patients in the recurrent and non-recurrent TSCC groups showed no evidence of disease, whereas 11 and 8 were alive with the disease. Local recurrence or distant metastases led to the deaths of six patients in the recurrent TSCC group and five in the non-recurrent TSCC group. No significant differences in survival were observed between the two groups. FPCT parameters can detect the recurrence of locally advanced TSCC after multimodal treatment. Early salvage surgery can improve the treatment outcomes for recurrent TSCC.

Askin\'s tumors are rare malignant neoplasms located in the thoracopulmonary region and mainly occur in children and adolescents. In this report, we describe a case of histologically proven Askin\'s tumor in a 24-year-old male. The patient was admitted with a history of 3-month lower back pain and with a rare presentation of paraparesis.

The thyroid cartilage metastatic involvement is an extremely rare entity. It can be asymptomatic at the earlier stage and can become symptomatic later on. Involvement of thyroid cartilage is frequent in melanoma and renal and rarely reported in an advanced stage of carcinoma prostate, breast, and lung. These cases were usually reported on positron emission tomography/computed tomography (PET/CT) as can often easily be missed on computed tomography scan alone. We present a case report of metastatic involvement of thyroid cartilage in squamous cell carcinoma of buccal mucosa detected on the whole-body 18F-fluorodeoxyglucose PET/CT.

Askin tumors are rare malignant neoplasms located in the thoracopulmonary region and mainly occur in children and adolescents. In this report, we describe a case of histologically proven Askin\'s tumor in a 24-year-old male. The patient was admitted with a history of 3-month lower back pain and with a rare presentation of paraparesis.

Epithelioid angiosarcoma is a rare subtype of angiosarcoma, with metastases occurring in more than 50% of cases and the lung is the most organ which is involved. Whole-body fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) has demonstrated its clinical utility in the early detection of metastases in angiosarcoma. It is helpful to differentiate between benign lesions with low FDG uptake as compared to malignancies with high FDG avidity. Here, we present a rare case of a young man with epithelioid angiosarcoma, in which FDG PET/CT has demonstrated metastatic sites (especially lung metastases).

Tertiary hyperparathyroidism (TH) is a rare condition that develops from secondary hyperparathyroidism in cases when the secretion becomes autonomous. Brown tumors (BTs) are rare skeletal lesions of hyperparathyroidism that may mimic cancer metastasis. We report a case of a patient who was diagnosed with TH with multiple BTs which mimics osteolytic/osteoblastic metastases that were evaluated with two fluorodeoxyglucose positron emission tomography scans with an interval of 23 months in the preoperative and postoperative period.

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is an unusual subtype of cutaneous lymphoma and clinically appears as erythematous, subcutaneous infiltrates, and recurrent papulonodules. It is defined as a rare cytotoxic a/b T-cell lymphoma characterized by primary involvement of subcutaneous tissue-mimicking panniculitis and a predominant CD3+/CD4/CD8+ phenotype in (2005) the World Health Organization-European Organization for Research and Treatment of Cancer classification for cutaneous lymphomas. On metabolic imaging, these lesions are invariably fluorodeoxyglucose (FDG) avid. SPTCL which presents as a breast mass is a rare entity. Here, we present a case of SPTCL presents as FDG avid breast mass and subcutaneous nodules.