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Narendra Nair

Publications and source records attributed to Narendra Nair.

15 recordsLinked to original sources
PubMed2006

Potential clinical role of FDG-PET in detecting sarcomatous transformation in von Recklinghausen's disease: a case study and review of the literature.

BACKGROUND: The diagnosis of sarcomatous transformation of plexiform neurofibromas in Neurofibromatosis-1 (NF 1) is a clinical and radiological challenge. Considerable overlap exists in the clinical and the radiological characteristics between the benign enlarging neurofibromas and their counterparts undergoing malignant changes. Surgical biopsy to rule out suspicious malignant transformation is often a problem in deep seated lesions. METHODS: We, in this paper, explore the clinical utility of FDG-PET in detecting and assessing this life threatening complication of neurofibromas. A case is described with FDG-PET and MRI documentation of such transformation and subsequent histopathological correlation. The case upholds the potential advantages of a FDG-PET over the conventional imaging modalities. A review of the existing literature is also carried out; a total of four published reports on this issue were identified in English literature by searches of Pubmed. RESULTS AND CONCLUSION: FDG-PET appeared a reliable as well as sensitive noninvasive technique that might minimize unnecessary deep surgical biopsy to rule out malignant transformation in cases of NF-1 with features of enlargement of a preexisting peripheral nerve sheath tumour, pain or neurodeficit.

Adult↗
PubMed2006

"Cold" vertebrae on F-18 FDG PET: Causes and characteristics.

BACKGROUND: Photon deficiency in the vertebrae on FDG PET can arise as a result of varying etiologies, and a proper interpretation of this incidental observation is essential for an accurate diagnosis. MATERIALS AND METHODS: Cases with "cold" vertebrae on FDG PET resulting from different causes were selected and analyzed from a population of patients with cancer who underwent conventional whole-body FDG PET for staging, disease viability assessment, or treatment monitoring purposes. The patterns were studied and correlated with the appropriate clinical setting. RESULTS: Three distinct causes were observed. Postexternal radiotherapy photopenia involving multiple vertebrae corresponding to the radiotherapy portals represented the most common setting for such findings followed by the destruction of the vertebral marrow cavity in the center by metastatic tumor cells. The third situation was vertebral hemangioma, in which relative photon deficiency in the concerned vertebra was incidentally observed amid generalized marrow uptake after colony-stimulating factor therapy. The characteristics and features of "cold" vertebrae in prototype cases selected from each etiology are described with illustrations. CONCLUSION: Pattern recognition coupled with further correlation of this observation is the key to the correct diagnosis of the underlying etiology, which can at times have a bearing on subsequent management. With the growing use of FDG PET, this observation is likely to be encountered with increasing frequencies and possibly newer etiopathologies.

Adenocarcinoma↗
PubMed2006

F-18 FDG PET scan findings in a case of carcinoma of the breast with a rare site of metastases to the gingival region.

Malignant tumors of the breast have an inherent potential to metastasize more often to the regional lymph nodes. It is rare to find a metastasis to the oral region from a primary in the breast, but when this does occur, it usually involves the jawbones rather than the soft tissues. A 33-year-old premenopausal woman, a diagnosed case of locally advanced right breast carcinoma, underwent right modified radical mastectomy followed by chemotherapy as per the institutional protocol. She presented after 2 years with an exophytic growth in the upper alveolar region of the oral cavity. Biopsy indicated gingival metastasis from a poorly differentiated adenocarcinoma of the breast. She was referred for F-18 FDG PET scan to evaluate the disease status before planning radiotherapy to the gingival metastasis. F-18 FDG PET scan was done after intravenous injection of 370 MBq (10 mCi) of tracer. Whole-body PET images were reconstructed in iterative algorithm (OSEM). Whole-body F-18 FDG PET scan showed hypermetabolic foci in the midmaxillary region (SUV max: 6.5), upper end of the right humerus, a large hypermetabolic area in the upper zone of the right lung with contiguous hilar node involvement on the right side of the lung, and an area of intense hypermetabolic activity in the left acetabular and ischial region. The present case demonstrates a rare site of metastasis in the oral region from carcinoma of the breast.

Adenocarcinoma↗
PubMed2005

Pediatric thyroid cancer.

BACKGROUND AND OBJECTIVE: The treatment of pediatric thyroid cancer evokes considerable controversy. The extent of surgery and role of postoperative radioactive iodine are not clearly defined. We analyzed the behavior of pediatric thyroid cancers and its management. METHODS: Eighty-three patients, from 1964-2000, were identified by a search of our database. The clinical course of 26 patients was not evaluated because of inadequate follow-up and the remaining 57 patients were included in the final survival analysis. These 26 patients were included for analyses of epidemiological data. RESULTS: There were 27 males and 56 females. Cervical lymphadenopathy was a common presentation (57.8%). The predominant histology was papillary carcinoma (57%). Sixteen patients (19.2%) had pulmonary metastases at presentation. Patients with cervical nodes had a significantly higher incidence of pulmonary metastasis compared to those who presented with thyroid nodule (P = 0.037). Five patients (31.2%) with pulmonary metastases had a negative chest X-ray and were detected only on the radioiodine scan. At median follow-up of 64 months, all 57 patients were alive, 10 with disease and 47 disease free. CONCLUSION: Despite its advanced stage at presentation, pediatric thyroid cancer is associated with an excellent prognosis. We advocate total thyroidectomy and radioactive iodine as the best management option as the incidence of pulmonary metastases is high.

Adolescent↗
PubMed2005

Unsuspected metastatic male breast nodule from synovial sarcoma detected by FDG PET.

The literature of serendipitous findings on whole-body FDG PET continues to grow. Whole-body FDG PET imaging of a 24-year-old man with treated synovial sarcoma of the right upper extremity showed an abnormal focus of activity over the right chest in addition to abnormal uptake in the lungs. On reexamination, he was found to have a hitherto unknown 2.5-cm mobile nodule in the right breast. Histopathology confirmed it to be metastasis from the synovial sarcoma. Extramammary malignancies metastasizing to the breast constitute approximately 2% of all breast tumors.

Adult↗
PubMed2005

Detection of thyroid carcinoma in wall of a cystic lesion by FDG PET.

PURPOSE: Three cases are described, in which positron emission tomography (PET) led to the diagnosis of carcinoma in solitary thyroid nodules (STN), which were considered benign by clinical assessment, ultrasonography, and fine needle aspiration cytology (FNAC). MATERIALS AND METHODS: These 3 cases were from a group of 51 patients with solitary thyroid nodules that were nonfunctioning or "cold" on pertechnetate scans that were later studied with FDG PET scanning. RESULTS: Of the entire group, 28 patients showed the nodule to be nonfunctioning on FDG scans. Of these, 3 showed one or more small foci of intense FDG uptake in the periphery. On histopathology, these sites were found to harbor carcinoma, papillary carcinoma in 2 patients and a follicular variant of papillary carcinoma in one. CONCLUSIONS: These cases demonstrate the usefulness of FDG PET in detection of cancer that may lurk in the wall of a cystic thyroid nodule, often misinterpreted as benign by conventional methods.

Adult↗
PubMed2005

Selected cases demonstrating the value of furosemide-primed 18F-FDG PET in identifying adrenal involvement.

The adrenals are often a site of metastatic spread of cancer, and evaluation of the adrenals is important in assessing the extent of disease involvement in several malignancies. PET with 18F-FDG has been found extremely effective in detecting adrenal involvement not identified on CT or not meeting the CT size criteria for malignancy. However, evaluation of the adrenals and of retroperitoneal adenopathy or other pathologic conditions with 18F-FDG PET can be complicated at times by normal accumulation of the tracer in the uppermost renal calyx because of its somewhat posterior orientation, particularly when it is dilated. It is not infrequent for physicians to report doubt about adrenal involvement and to suggest that the PET findings be correlated with CT findings. This problem can often be circumvented clinically by administering intravenous furosemide (dosage adjusted according to body weight) to remove 18F-FDG activity from the renal pelvicalyceal system and by rescanning approximately 15-20 min later using 1-2 bed positions that include the renal area. We present 5 case vignettes, with representative illustrations, providing convincing evidence of the usefulness of this simple, noninvasive interventional procedure in ruling out suspected adrenal involvement that is otherwise difficult to assess, thereby obviating any further confirmation.

Adenocarcinoma↗
PubMed2004

Unusually elevated liver radioactivity on F-18 FDG PET in Hodgkin's disease: hepatic 'superscan'.

Increased focal concentration of FDG in the background of relatively lower normal hepatocyte uptake is usually regarded as the hallmark of metastatic involvement of the liver from a known primary. The authors present the clinical, radiologic, and laboratory profile of a very unusual hepatic uptake pattern in a case of Hodgkin disease, in which the FDG PET showed intensely diffuse hepatic tracer uptake and was the earliest indicator of extensive hepatic involvement by the disease process. The diagnosis of hepatic involvement with lymphoma was inferred. As experience with FDG PET is growing, it is important to become familiar with the various physiological and pathologic FDG uptake patterns. The term "hepatic superscan", demonstrating intense diffuse hepatic tracer uptake coupled with surprisingly low brain and cardiac FDG uptake, owes its origin from its apparent similarity with the superscan seen in conventional skeletal scintigraphy and represents an entity hitherto undescribed.

Adult↗
PubMedDate not supplied

(18)FDG PET in primary oat cell carcinoma of the esophagus.

The role of FDG-PET in oat cell carcinoma of the esophagus is hitherto unexplored. A MEDLINE search using the terms "small cell carcinoma" or "oat cell carcinoma" combined with "FDG-PET" yielded no report on this issue till date. We report, in this article, two cases depicting the usefulness of this modality in the management of this uncommon neoplasm. While reevaluation of unsuspected metastatic sites missed by other modalities suggest its role in M staging, whole body FDG PET (both baseline as well as post treatment) may find important role in treatment monitoring and evaluation in residual viable disease, taking into account the systemic nature of the disease.

Aged↗