Rare Case of Primary Leiomyosarcoma of Bone - Findings on 18F-fluorodeoxyglucose Positron Emission Tomography/Computed Tomography.

Primary leiomyosarcoma of bone (PLB) is a rare tumor, constituting <0.7% of all primary bone malignancies. It is clinically aggressive with heterogeneous presentation and a dismal prognosis. The most common presentation is pain with swelling and pathological fracture at times. Limited literature is available on PLB and only about 150 cases have been reported to date with only a few case reports defining the utility of 18F-fluorodeoxyglucose (18-F FDG) positron emission tomography/computed tomography (PET-CT) in its management. We hereby present a case of primary leiomyosarcoma of the right distal femur and the role of FDG-PET-CT in its management.

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.

Recurrent Renal Cell Carcinoma Presenting as Port-Site Metastases, Detected on 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography.

The incidence of port-site metastases (PSMs) varies with the tumor type with adenocarcinoma having a high incidence. However, it is rarely seen in urological malignancies and more so in renal cell carcinoma (RCC). We hereby describe one such case of PSM after laparoscopic radical nephrectomy for RCC, which was detected on 18F-fluorodeoxyglucose positron emission tomography-computed tomography.

Small Chyle Leak Localized on Lymphoscintigraphy with Single-Photon Emission Computed Tomography-Computed Tomography.

Chylothorax refers to the accumulation of triglyceride-rich fluid (chyle) within the pleural space. We described a case of spontaneous chylothorax in an infant. Lymphoscintigraphy was performed with 99 m-Tc sulfur colloid which showed tracer accumulation into thoracic cavity, and single-photon emission computed tomography/CT (SPECT/CT) revealed leak in the thoracic duct at D8 vertebral level as the cause. We, thus, emphasize the role of lymphoscintigraphy with SPECT/CT in identification of cause and guiding the management of chylothorax, especially when surgical treatment is planned.

Rare Case of Phyllodes Tumor of Breast with Cardiac and Pancreatic Metastases: Findings on 18F-FDG PET/CT.

Phyllodes tumor (PT) represents a rare type of breast tumor arising from the stromal component rather than the epithelium. Metastatic spread occurs hematogenously, with lung, bone, brain, and liver being the most common sites. We present the 18F-FDG PET/CT scan of one such case of phyllodes tumor showing cardiac and pancreatic metastases, which are an extremely rare occurrence.

False-Positive Radioiodine Uptake in the Cervix in a Patient with Thyroid Cancer.

Radioactive iodine (RAI) accumulation is commonly used for the detection of metastatic disease posttotal thyroidectomy. However, false-positive results have been reported due to abnormal RAI accumulation in some benign pathologies apart from metastatic sites. Here, we present one such case where false-positive I-131 uptake in the pelvis which localized to the cervix and was attributed to menstruation.

Delayed Recurrence of Gall Bladder Cancer as Port-site Metastases with Occult Primary Detected on Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography: A Tale of Two Cases.

Laparoscopic cholecystectomy is a fairly common procedure and is currently considered the gold standard for cholecystectomy. However, the laparoscopic procedure in the presence of gall bladder cancer (GBC) is associated with the risk of port-site metastasis (PSM). Furthermore, in few cases, GBC remains occult even on postoperative histopathology and presents with PSM remotely. Here, we describe two such cases of GBC with occult primary who presented with PSM and also defined the role of fluorine-18 fluorodeoxyglucose positron emission tomography-computed tomography in the management of such cases.

Steroid-Induced Activated White Adipose Tissue Detected on 18F-FDG PET/CT.

White adipose tissue (WAT) usually shows negligible 18F-FDG uptake due to negligible glucose utilization. However, corticosteroids alter the biodistribution of 18F-FDG and increase uptake in WAT. Here, we present a case of diffusely increased 18F-FDG uptake in WAT secondary to high-dose corticosteroid therapy for nephrotic syndrome.

Aberrant Radioactive Iodine Uptake in Simple Ovarian Cyst: A Rare Finding.

I-131 whole body scan and therapy play an important role in the follow-up of differentiated thyroid carcinoma patients for the detection of residual thyroid tissue and metastatic disease. However, various false-positive findings have been reported in the literature which can appear as metastases. Here, we present one such case, in which an I-131 posttherapy scan revealed false-positive radioactive iodine uptake which localized to a simple ovarian cyst.

Utility of Axillary Reverse Mapping (ARM) and Incidence of Metastasis in Arm Draining Lymph Nodes in Patients with Breast Cancer.

Objective Lymphedema of the upper limb is the most common complication in patients with breast cancer, who require axillary lymph node (LN) dissection. Proposition of identifying upper limb draining LN and preserving it, during axillary dissection can reduce significant postoperative morbidity, but it has the risk of inadequate oncological resection. This study was planned to find out metastatic rate in axillary reverse mapping (ARM) nodes in our population. Materials and Methods Lymphoscintigraphy (LSG) was performed using intradermal injection of 99m Tc Sulfur Colloid into ipsilateral second and third interdigital web spaces of hand in patients with breast cancer. Planar, single-photon emission computed tomography-computed tomography images were acquired followed by intraoperative localization of arm draining LNs using Gamma Probe. All identified ARM nodes were dissected and sent for histopathological examination to confirm metastatic involvement. Results Twenty eligible patients were prospectively analyzed. The identification rate of arm draining LN with LSG was 90% (18/20). Among 14 eligible patients included in the study, ARM node metastasis was seen in two patients. A total of 64 ARM nodes were dissected from 14 patients, 4/64 nodes (2 patients) were positive for metastases (6.25%). Of the six patients excluded from the study, in 1 patient ARM node could not be identified on Gamma Probe, in two cases, it could not be retrieved surgically, in next two cases ARM could not be identified on LSG and remaining one case was removed because of previous surgical intervention. Conclusion In the current study, LSG showed the identification rate of 90% for ARM nodes in patients with carcinoma breast and metastatic involvement was seen in 6.25% (4/64) of these nodes in 2/14 (14.2%) patients, which is in agreement with previously published data. Oncological safety of preserving ARM nodes needs to be evaluated in the larger population.

Cutaneous Metastases as Initial Presentation of Lung Carcinoma.

Breast cancer, in women, and lung cancer, in men, are the most common origins of cutaneous metastasis. Lung cancer can metastasize to any organ but mostly to the contralateral lung, liver, adrenal gland, bones, and brain. Over 1-12% of patients with lung cancer can develop skin metastasis. Non-small cell lung cancer includes 87% of lung cancer cases. Adenocarcinomas subtype accounts for approximately 40% of all lung cancers and is the most common histology in women. A woman's lifetime risk of developing lung cancer is 1 in 16 women but lower than that of a man (1 in 13 men). The survival rates of women with lung cancer are usually higher than those of men. Herein, we report the case of a 66-year-old female who presented with painless multiple skin nodules over the chest back and axilla for three months. On evaluation, biopsy and immunohistochemistry were done from skin nodules suggestive of adenocarcinoma. CT thorax showed lung mass and was diagnosed as a case of metastatic adenocarcinoma, primary being from the lung. Our case demonstrated that skin metastasis could be the first sign of internal malignancy. Metastasis to the skin is often a preterminal event that heralds a poor prognosis.

Metabolic Adaptations in Cancer Stem Cells.

Cancer stem cells (CSCs) are a small and elusive subpopulation of self-renewing cancer cells with remarkable ability to initiate, propagate, and spread the malignant disease. In addition, they exhibit increased resistance to anticancer therapies, thereby contributing to disease relapse. CSCs are reported to be present in many tumor types such as melanoma, sarcoma, mammary tumors, colon cancer and other solid tumors. These cells from different tumors show unique energetic and metabolic pathways. For example, CSCs from one type of tumor may predominantly use aerobic glycolysis, while from another tumor type may utilize oxidative phosphorylation. Most commonly these cells use fatty acid oxidation and ketone bodies as the main source of energy production. CSCs have a remarkable ability to reprogram their metabolism in order to survive under adverse conditions such as hypoxia, acidosis, and starvation. There is increasing interest to identify molecular targets that can be utilized to kill CSCs and to control their growth. In this review, we discuss how an understanding of the unique metabolism of CSCs from different tumors can offer promising strategies for targeting CSCs and hence to prevent disease relapse and to treat the metastatic disease.