Sudha R. Kini

The diagnosis of malignant follicular neoplasms of the thyroid by needle biopsy

To test the value of needle biopsy for a diagnosis of follicular thyroid malignancy, we compared needle biopsy and surgical diagnoses for 1005 patients. There were 67 follicular carcinomas, 34 Hurthle cell carcinomas, and 39 follicular variants of papillary carcinoma. Malignancy was diagnosed or suspected by biopsy for 114 of the cancers (82%), considered “possible” for 24 (17%), and misdiagnosed as “benign” in 2. Sensitivity of fine‐needle biopsy (FNB) for the diagnosis of 39 cancers approximated that of large‐needle biopsy (LNB) for 101 cancers 2 cm or larger. Diagnostic specificity for cancer varied with the degree of cytologic or histologic abnormality. Specificity of FNB was comparable to LNB on nodules large enough for both procedures. Specificity of FNB on nodules too small for LNB was substantially less. The sensitivity of needle biopsy allows selection of many follicular nodules for observation. Knowledge of the probability of cancer for each cytologic or histologic diagnosis is useful in determination of the need for thyroid surgery.

Biliary tract cytology in specimens obtained by direct cholangiographic procedures: A study of 74 cases

A retrospective review of bile (BL) and biliary tract brushings (Br) obtained by endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC) was undertaken to determine the sensitivity and specificity of cytology in the diagnosis of pancreaticobiliary malignancies. A total of 104 cytologic specimens (PTC‐BL 15, PTC‐Br 13, ERCP‐BL 8, ERCP‐Br 68) received between 1990 and mid‐1994 from 77 patients who had undergone ERCP and/or PTC primarily for biliary stricture were reviewed. Specimens were unsatisfactory/inadequate in 11 (10.6%), benign in 41 (39.4%), suspicious in 25 (24%), and positive for malignant cells in 27 (26%). Follow‐up was available in 74/77 patients; 46 (59.7%) had tissue confirmation while 28 (32.5%) had adequate clinical follow‐up based on chart review. Of those with histologic confirmation, there were 32 malignant and 14 benign cases. The overall sensitivity and specificity of PTC‐ and ERCP‐obtained cytologic specimens were 88.9 and 95.7% respectively. There was only one false positive case (ERCP‐Br). Overall positive predictive value was 96%, negative predictive value 88%, and accuracy 96%. PTC had a significantly lower sensitivity rate (42.8%) and higher rate for unsatisfactory specimens (21%) compared with ERCP‐obtained material (100 and 1.9%). Bile obtained by PTC or ERCP appeared less sensitive in detecting malignancies compared with endoscopic brushing using either technique (BL 50% vs. Br 100%). All three false negative cases were PTC‐BL specimens. Of the 17 suspicious cases, eight were confirmed histologically as malignant, four were clinically consistent with malignancy, and five showed marked inflammatory atypia on biopsy. Positive predictive value and accuracy rate of a “suspicious cytology” diagnosis were 69 and 80.5%, respectively. Inadequate specimen, poor cellular preservation, and cells obscured by bile all interfere with proper cytologic evaluation. Experience is necessary to appreciate subtle malignant changes in well differentiated carcinomas. Communication between the cytopathologist and the clinician is critical in the accurate interpretation and proper management of the patients. Diagn Cytopathol 1996;14:334–348.

Prospective Study To Determine the Volume of Pleural Fluid Required To Diagnose Malignancy

BACKGROUND The optimal volume of pleural fluid to diagnose a malignant effusion is unknown. Our study was designed to demonstrate if a minimum pleural fluid volume (10 mL) is equivalent to a large volume thoracentesis to make a cytopathologic diagnosis of malignancy. METHODS A total of 121 thoracentesis samples were obtained from 102 patients with suspected or known malignant effusions. Pleural fluid was collected in three aliquots for cytologic examination (10 mL, 60 mL, > or = 150 mL). The pathologist was blinded to patient identifiers and aliquot volume. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated for each volume for the diagnosis of malignancy. RESULTS Pleural malignancy was diagnosed in 90 patient encounters (74.4%). For direct smear/cytospin, there was increased sensitivity and NPV for 60 mL (P = .0058 and P = .045, respectively) and for > or = 150 mL (P < .001 and P = .009, respectively) compared with 10 mL. For combined direct smear/cytospin and cell block preparations, statistical significance for sensitivity and NPV existed only between the 10 mL and > or = 150 mL specimens (P = .0099 and P = .033, respectively). No statistical difference existed for specificity or PPV for any aliquot volume. CONCLUSIONS The sensitivity for diagnosis of pleural malignancy is dependent on the pleural fluid volume extracted during thoracentesis. Volumes of 10 mL do not perform as well as larger volumes. When both direct smear/cytospin and cell block preparations are used, we recommend > or = 150 mL, whereas when only direct smear/cytospin is used, 60 mL is adequate for the diagnosis a malignant pleural effusion.

The needle biopsy diagnosis of PAPILLARY THYROID CARCINOMA

One hundred five cases of papillary thyroid carcinoma (PTC) were studied by needle biopsy and surgically confirmed in a 30‐month period. Eight years were required to diagnose the same number of cases without the use of needle biopsies. Identification of clinically unsuspected cancer and confirmation of clinical “possible” cancer diagnoses accounted for 30% of this change. Seventy percent was accounted for by the increase in nodules referred for evaluation. The accuracy of fine‐needle biopsy (FNB) improved with experience. Positive diagnoses of PTC were made in 19 of the first 35 PTCs and in 33 of the last 35. False‐negative and unsatisfactory FNBs decreased from seven in the first third of the study to zero in the last third. Large‐needle biopsy (LNB), initially used to check FNB, became less necessary as experience increased. Both FNB and LNB were more specific when papillary areas were included in the biopsy procedure, and approached the specificity of surgical biopsy. The increase in indentifying PTC may require modification of the therapeutic implications of this diagnosis.

Signet ring cell lymphoma of the thyroid: a case report.

The first case of extranodal signet ring cell lymphoma involving the thyroid gland is reported in a 53-year-old woman with Hashimotos thyroiditis. Since 1978, 24 cases of signet ring cell lymphoma, all involving primarily nodal tissue, have been documented in the literature. This rare neoplasm is believed to be a variant of non-Hodgkins follicular lymphoma, which may be mistaken for metastatic poorly differentiated adenocarcinoma.

“Arias-Stella reaction”-like changes in endocervical glandular epithelium in cervical smears during pregnancy and postpartum states—a potential diagnostic pitfall

A wide spectrum of histologic changes has been described throughout the female genital tract during pregnancy and in the postpartum period. Of these, the endometrial glandular changes referred to as the Arias‐Stella reaction have classically been a diagnostic pitfall in histologic sections. Pregnancy‐related changes are also reflected in cytologic material obtained from the cervix and vagina. Both glandular and stromal alterations may be seen. The changes involving endocervical glandular epithelium are often alarming enough to cause diagnostic difficulties, especially when the history of pregnancy is not provided. We report 13 cases where marked glandular changes led to diagnostic misinterpretations. These were characterized by cyto‐ and karyomegaly, a high nuclear to cytoplasmic ratio, round to oval nuclei with smudgy chromatin imparting a ground glass appearance, frequent intranuclear inclusions, and vacuolated to dense variable cytoplasm. The cytologic diagnoses ranged from “glandular atypia” to “suspicious for adenocarcinoma.” Follow‐up was available in 11/13 cases. In 9/11 cases, subsequent cervical smears on multiple occasions were negative. Cervical biopsies and/or dilatation and curettage in 4/11 cases did not show significant glandular abnormalities. The glandular changes encountered in cytologic material were similar to those described histologically in the Arias‐Stella reaction involving the cervix. This similarity and the fact that these changes disappeared upon termination of the pregnancy favors the presumption that they represent the Arias‐Stella reaction. Awareness of these changes during pregnancy and postpartum may prevent interpretive errors and unnecessary surgical procedures. Diagn Cytopathol 1996;14:349–355.

Is Lymphoma of the Thyroid a Disease Which Is Increasing in Frequency

It has been said that primary lymphoma of the thyroid gland is rare.1–9 The number of cases reported in the world literature has been cited at approximately 250.9 Although this is probably an underestimate, it is a general indication of the frequency of this disease. Most of the tumors are histiocytic or lymphocytic lymphomas. Primary involvement of the thyroid gland by Hodgkin’s disease is truly exceedingly rare.10 The diagnoses have almost always been made retrospectively after operations for different presumptive diagnoses.

The impact of needle biopsy on the diagnosis of the thyroid nodule

Management of the patient with a thyroid nodule has been the subject of debate for many years. The essential question for any given nodule is whether the risk of cancer is great enough to justify the risk of surgical treatment. Granted the risks are very small when operations are performed by expert thyroid surgeons in first rate hospitals. Nevertheless, even these small risks must be justified when one is dealing with a problem which is as common as thryoid nodules, especially since most thyroid nodules are benign, most of those which are malignant are not very agressive, and the few highly lethal are almost always incurable by surgical methods.

Respiratory Specimen Types for Cytologic Diagnoses Specimen Procurement, Collection Methods, Specimen Submission, Cytopreparation, and Staining

The uniqueness and versatility of a broad range of specimens available from the lower respiratory tract for cytopathologic evaluation have both increased the diagnostic yield of pulmonary malignancies and been very effective in the diagnosis of several nonneoplastic and infectious disease processes. Cytologic evaluation of one or more of the various specimen types (Table 2-1) is indispensable in clinical practice in the management of patients with pulmonary disorders.

Pulmonary Neuroendocrine Tumors: Carcinoid Tumors, Atypical Carcinoids, Large Cell Neuroendocrine Carcinoma, and Small Cell (Undifferentiated) Carcinoma

The spectrum of pulmonary neuroendocrine tumors is very wide, encompassing several diagnostic entities. Their classification is quite complex, as is the terminology. Some neoplasms are encountered more frequently than are others. Not all are identified in cytologic specimens, especially the preneoplastic neuroendocrine lesions that are included in the most recent World Health Organization (WHO) and International Association for the Study of Lung Cancer (IASLC) classification of the lung tumors. This chapter will focus only on neoplasms that are more frequently encountered, including: (1) typical carcinoid tumor; (2) atypical carcinoid tumor; (3) large cell neuroendocrine carcinoma; and (4) small cell (undifferentiated) carcinoma. These four neoplasms present a spectrum of morphologic features ranging from benign-appearing uniform cellular patterns to highly anaplastic ones. Their biologic behavior likewise ranges from that of a benign protracted course in typical carcinoid to an aggressive one with a fatal outcome, as seen in large cell neuroendocrine and small cell carcinomas. Despite the differences, pulmonary neuroendocrine tumors share several features: namely, their origin (Kulchitsky cells), certain morphologic features (e.g., neuroendocrine growth patterns), and positive reactivity to most neuroendocrine markers. They all ultrastructurally exhibit dense core neurosecretory granules, and some are associated with ectopic hormone production.