Multifocal Burkholderia cepacia Infection in Postrenal Transplantation Fever : Role of 18 F-FDG PET/CT in Treatment Optimization.

ABSTRACT: Nosocomial Burkholderia cepacia infection in the clinical setting of postrenal transplantation pyrexia of unknown origin and the role of 18 F-FDG PET/CT in treatment optimization in such situation is presented in this report. The consequence of fastidious infection by nosocomial colonizing organisms like B. cepacia can be catastrophic in immunocompromised postrenal transplant individuals causing severe urinary tract infection. In the presented case, following 2 weeks of IV antibiotics, the patient didn't show clinical response, and FDG PET scan recognized multifocal infective sites early, likely representing immune reconstitution inflammatory syndrome and timely appropriate and optimal treatment salvaged the renal graft.

Sellar-Parasellar and Petrous Bone Metastasis from Differentiated Thyroid Carcinoma: Imaging Characteristics and Follow-Up Profile Post Radioiodine Therapy.

Sella turcica and petrous bone metastasis from differentiated thyroid carcinoma are rare clinical entities, with only a few limited cases reported to date. Two cases, one of sella turcica metastasis and the other of petrous bone metastasis from carcinoma of the thyroid gland, are presented. The cases diagnosed to have arisen from poorly differentiated thyroid carcinoma and follicular carcinoma of thyroid, respectively, subsequently underwent total thyroidectomy, radioiodine (RAI) scans and RAI therapies with iodine-131, external radiotherapy, and levothyroxine suppression with follow-up. Their clinical symptoms gradually subsided, with reduction in serum thyroglobulin, and finally resulted in disease stabilization. With the multimodality therapeutic approach, both patients are alive to date, with 48- and 60-month survival post diagnosis, respectively.

"Stocking Pattern Metabolic Captivity" of Legs on 18 F-FDG PET-CT in Necrotizing Fasciitis: Potential Complimentary Role in Differential Diagnosis and Assessment of Disease Extent in a Life-Threatening Condition.

A rare and fatal life-threatening case of necrotizing fasciitis (initially presenting with skin-deep superficial lesions and clinical suspicion of paraneoplastic syndrome) is described, who was finally diagnosed with the help of fluorodeoxyglucose-positron emission tomography (FDG-PET)/computed tomography (CT) as more extensive infectious process. A 36-year-old male presented with bilaterally symmetrical cutaneous lesions involving lower limbs that rapidly progressed to ulcerative lesions and pancytopenia. In view of suspicion of paraneoplastic manifestation, the patient underwent 18 F-FDG-PET/CT to rule out any underlying malignancy. The FDG-PET/CT findings confirmed hypermetabolism circumferentially along the fasciae of bilateral lower extremities while sparing muscles and subcutaneous fat from below the knee till toe with diffused hypermetabolic marrow, and no evidence of focal disease suggesting malignancy. Biopsy turned out to be superficial necrolytic fasciitis. The patient's condition deteriorated and, 20 days following the scan, the patient succumbed secondary to severe pancytopenia and hypotension. The case raises the importance of high degree of suspicion and prompt diagnosis of this condition, where FDG-PET/CT imaging can play a valuable complimentary role. Such awareness could be lifesaving due to early optimal treatment in the disease course.

Role of PET/Computed Tomography in Elderly Thyroid Cancer: Tumor Biology and Clinical Management.

PET/computed tomography (CT) studies can be potentially useful in elderly thyroid carcinoma patients for exploring the disease biology, especially in metastatic setting and thereby directing appropriate therapeutic management on case-to-case basis, adopting nuclear theranostics, and disease prognostication. With the availability of multiple PET radiopharmaceuticals, it would be worthwhile to evolve and optimally use FDG and the other non-fluorodeoxyglucose and investigational PET/CT tracers as per the clinical situation and need and thereby define their utilities in a given case scenario. In this regard, (I) differentiated thyroid carcinoma (DTC) including radioiodine refractory disease, poorly differentiated thyroid cancer (PDTC) and TENIS, (II) medullary thyroid carcinoma (MTC), (III) anaplastic carcinoma and (IV) Primary thyroid lymphoma (PTL) should be viewed and dealt separately.

An Unusual FDG-PET/CT Documentation in Aleukemic Leukemia Cutis: Atypical Penile, Scrotal, and Leg Muscles Involvement.

Aleukemic leukemia cutis (ALC) is a rare condition with a relatively poor prognosis, clinically presenting as skin and subcutaneous nodules commonly involving head and neck region with discrete atypical leukemic cells infiltrating in the skin on histopathology. The lesions on the genital area skin are seldom reported. A 49-year-old male presented with joint pains and multiple subcutaneous nodules clinically with biopsy proving it as leukemia cutis. Bone marrow aspiration and biopsy were suggestive of normocellular myeloid preponderant bone marrow with mild increase in eosinophils. The 18 F-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) revealed metabolically active FDG avid ill-defined soft tissue attenuation involving the entire length of penile shaft with central necrotic area, diffuse scrota skin thickening, and lateral compartment muscles of left leg, in addition to multiple hypermetabolic metastatic lymph nodes, and diffuse hypermetabolic marrow in humerii and femora. Despite prompt investigations and initiation of management, the patient succumbed in 15 days post-FDG PET/CT. The present report depicts an atypical case of ALC, with FDG PET-CT showing extensive and unusual sites of disease involvement, emphasizing its potential role in ALC.

Chest Wall Mass as the Dominant Presentation of Low-Grade B-Cell Non-Hodgkin's Lymphoma: A Case Report.

Low-grade B cell non-Hodgkin's lymphoma with dominant presentation of chest wall mass is presented in this report. The patient, a 65-year-old woman, presented with pain, rising skin temperature and redness, and swelling on the right lower chest wall. The histopathological examination revealed non-Hodgkin's lymphoma; the staging fluorodeoxyglucose-positron emission tomography/computed tomography demonstrated stage IVE disease, with hypermetabolic active disease in the right anterolateral chest wall in the form of large soft tissue mass and subcutaneous tissue with underlying bony erosion with extension into right anterior cardiophrenic space and superiorly up to right second costosternal region along the right internal mammary vessels. This was along with hypermetabolic active right axillary, right supraclavicular and left inguinal lymphadenopathy, and thickened hypermetabolic posterior right pleura with ametabolic right-sided pleural effusion. Bone marrow biopsy revealed uninvolved bone marrow. On follow-up after eight cycles of R-CHOP chemotherapy, the mass had completely resolved on contrast-enhanced computed tomography.

Differential tumor biology between locoregional and distant metastasis in a patient with TENIS with TKI-resistant aggressive recurrent disease: a comparative evaluation with FDG, 68Ga-DOTATATE and 68Ga-PSMA-11 PET-CT.

The molecular PET-CT imaging profile of an interesting case of differentiated thyroid carcinoma, later transformed into with thyroglobulin elevation and negative iodine scintigraphy (TENIS) with tyrosine kinase inhibitor (TKI) resistant recurrent aggressive disease, is presented. The patient was evaluated to assess SSTR-2 or PSMA expression to explore the possibility of any effective targeted nuclear therapy. 18F-FDG, 68Ga-DOTATATE and 68Ga-PSMA-11 PET/CT was performed, which revealed tracer avidity in all 3 scans in the extensive loco-regional disease of large ill-defined retropharyngeal and retro-tracheal soft tissue eroding cricoid cartilage, extending into tracheal lumen and left sided strap muscles. On the contrary, there was no definite uptake in the multiple bilateral lung nodules, the scan findings indicating a differential tumor biology between loco-regional and distant metastasis.

Role of fluorine-18 fluorodeoxyglucose positron emission tomography in a case of renal cell carcinoma to differentiate tumor thrombus from bland thrombus.

Tumor thrombus is a rare complication of many solid tumors. We present a case of renal cell carcinoma whose baseline contrast-enhanced computerized tomography (CT) revealed an heterogeneously enhancing mass in the upper half of right kidney with tumor thrombus in the right renal vein extending to suprarenal inferior vena cava (IVC), crossing the cavoatrial junction and reaching up to the right atrium (Grade IV). Fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT imaging revealed large irregular right renal mass, hypermetabolic tumor thrombus extending from the right renal vein to suprarenal IVC reaching up to the right atrium. There was no FDG uptake noted in the infrarenal IVC and bilateral iliofemoral venous thrombi. Thus, 18F-FDG PET/CT was not only helpful in the staging, but was also helpful in differentiating tumor thrombus from bland thrombus in our patient.