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Frozen section in a cytological diagnosis of thyroid follicular neoplasm.

OBJECTIVE/HYPOTHESIS: Fine-needle aspiration biopsy is the most accurate diagnostic test for thyroid nodules, its only limitation being the diagnosis of follicular neoplasm that does not distinguish between benign and malignant follicular lesions. STUDY DESIGN: To determine the utility of intraoperative frozen-section analysis in cases of a cytological diagnosis of follicular neoplasm, a retrospective review of 66 patients with a solitary thyroid nodule and follicular neoplasm who underwent thyroid surgery was carried out. METHODS: Fine-needle aspiration was classified following the Papanicolaou Society of Cytopathology Classification, and frozen section was defined as malignant or "deferred." If a malignant diagnosis was made by frozen-section analysis, a total thyroidectomy was carried out. The extension of thyroid surgery in the deferred cases was based on the definitive histological diagnosis. RESULTS: Sixty-four cases were classified as deferred, and two as suspect for malignancy. Among the 64 deferred cases, 15 were malignant in the final pathological findings, and 49 were benign. The two suspect cases were papillary carcinoma. Frozen-section analysis classified 2 of 17 (11.7%) cases as follicular variant of papillary carcinoma that could not be diagnosed by cytological study. However, these two cases had a strong clinical evidence of malignancy. CONCLUSION: The routine use of frozen-section analysis is useless in cases of cytological diagnosis of follicular neoplasm on fine-needle aspiration biopsy, because of the low probability of achieving the diagnosis of follicular carcinoma and the inability to provide additional information apart from the clinical and the cytological data.

Adenocarcinoma, Follicular↗

Nonspecific interstitial pneumonia: a provisional category of idiopathic interstitial pneumonia.

PURPOSE OF REVIEW: Idiopathic interstitial pneumonias (IIP) represent a complex group of relatively rare entities with similar clinical, vaguely similar radiographic and differing histologic features. The recent international multidisciplinary consensus statement produced by the American Thoracic Society/European Respiratory Society aiming to standardize the classification of IIP recognizes nonspecific interstitial pneumonia (NSIP) as a provisional category. While not representing a single disease, but rather a collection of pathologic processes with similar histomorphology, NSIP has been a great source of confusion for pulmonologists, radiologists, and pathologists. RECENT FINDINGS: Lacking diagnostic clinical or radiographic features, NSIP is an IIP with recognizable and reproducible morphologic patterns different from usual interstitial pneumonia (UIP)-pattern as well as other disease patterns. And while overlap with UIP-pattern can be seen in individuals with multiple biopsy samples, those with either cellular or fibrosing variants of NSIP have a better prognosis than UIP-pattern patients. SUMMARY: A morphologic diagnosis of NSIP-pattern alerts the clinician to a wide spectrum of potential clinical possibilities and enables researchers to study both this fibrosing interstitial pneumonia pattern and the more common and deadly UIP-pattern separately. Thus, this provisional category is useful to both clinicians and researchers.

Humans↗

Classification and approach to bronchiolar diseases.

PURPOSE OF REVIEW: Bronchiolar abnormalities are relatively common and occur in a variety of clinical contexts. There have been an increasing number of terms, some of which are redundant, used in referring to various forms of bronchiolar disorders. The purpose of this review is to provide an updated classification scheme to facilitate the clinical approach to patients with suspected bronchiolar disease. RECENT FINDINGS: The spectrum of bronchiolar disorders is broader and more heterogeneous than previously recognized. In deciphering the potential significance of bronchiolar abnormalities, it is useful to distinguish those disorders in which the bronchiolar involvement is the dominant pathologic process, that is, primary bronchiolar disorders, from parenchymal or large airway diseases in which the bronchioles may become secondarily involved. Primary bronchiolar disorders include respiratory bronchiolitis, acute bronchiolitis, constrictive bronchiolitis, follicular bronchiolitis, diffuse panbronchiolitis, mineral dust airway disease, and a few other variants. Interstitial lung diseases with a prominent bronchiolar involvement include smoking-related interstitial lung diseases, cryptogenic organizing pneumonia, and hypersensitivity pneumonitis. Bronchiolitis can also be seen in large airway diseases such as chronic bronchitis, bronchiectasis, and asthma. SUMMARY: In the clinical approach to a patient with bronchiolar disease, primary bronchiolar disorders should be distinguished from predominantly parenchymal or large airway processes with bronchiolar involvement. The number of patterns of bronchiolar response to injury is limited and these patterns are generally non-specific in regard to cause. Appropriate diagnosis and management of patients with bronchiolar disorders depend on judicious correlation of clinical, physiologic, and morphologic manifestations.

Airway Obstruction↗

Distribution of fimA genotypes of Porphyromonas gingivalis in subjects with various periodontal conditions.

Fimbria encoded by the gene fimA is considered one of the main factors in the colonization of the oral cavity by Porphyromonas gingivalis. Allelic variation in fimA led to the classification of strains of P. gingivalis into six genotypes. The occurrence of P. gingivalis was determined by polymerase chain reaction using 16S rRNA primers in 302 subgingival samples obtained from 102 Brazilian subjects exhibiting different periodontal conditions. Distribution of fimA genotypes was assessed in 146 P. gingivalis positive samples by polymerase chain reaction using primers pairs homologous to the different fimA genes. P. gingivalis was detected in 51 of 57 (89.4%) patients with periodontal attachment loss, in six of 20 gingivitis patients (30.0%) and in two of 25 (8.0%) subjects with a healthy periodontium. Variant type II was the only type detected in 53 sites (39.3%), distributed among 19 periodontitis patients (37.3%) and in one patient with no periodontal destruction. Type Ib was the second most prevalent genotype in periodontitis patients (19.6%). Genotype V was not detected in the studied population. Type IV was the most commonly type found among gingivitis patients, either alone or in combination with other genotypes. Multiple genotypes were detected in nine sites (6.1%). A fimA genotype was not identified in 26 sites (17.8%) of 146 sites positive for P. gingivalis, suggesting that other alleles of fimA not yet sequenced may be prevalent in this population. These data demonstrated that P. gingivalis type II strains followed by type Ib are more prevalent in periodontitis patients from a multiracial population in Brazil, suggesting an increased pathogenic potential of these types.

Adolescent↗

Paraffin-immunohistochemical analysis of 226 non-Hodgkin's malignant lymphomas in the endemic area of human T-cell leukemia virus type 1.

A study was conducted to evaluate the usefulness of paraffin-immunohistochemistry for histopathological classification of non-Hodgkin's malignant lymphomas (NHML). the phenotypes of lymphoma cells and other cells were examined using 11 monoclonal and 3 polyclonal antibodies by the ABC method on paraffin-embedded tissue sections of 226 cases of NHML, comprising 94 B-cell lymphomas (B-ML) and 132 T-cell lymphomas (T-ML). In 219 NHML cases (96.8%), lymphoma cells reacted with more than one of these antibodies. A set of MB-1, Mx-pan B, L26, LN-1, LN-2 and anti-immunoglobulin light chain antibodies characterized each subtype of B-MLs, categorized according to the Kiel classification. Mantle-zone lymphoma (MzML) was added as one subtype. L26 stained the largest number of B-MLs (82.8%). B-cell chronic lymphocytic leukemia (B-CLL) was labeled most frequently by MB-1. MzML was characterized by reactivity of lymphoma cells with LN-2 and by the appearance of monoclonal immunoglobulin light chain along the cell membrane. Follicle center cell lymphomas were stained by LN-1 and LN-2, although a small number of proliferating cells were labeled by LN-1 in B-CLL, MzML and the immunocytoma lymphoplasmacytic/cytoid variant. MT-1 and/or UCHL-1 showed various degrees of reactivity with the cell membranes of lymphoma cells in 94.8% of T-MLs. Among the T-cell pleomorphic lymphomas of Suchi and Lennert, the adult T-cell leukemia/lymphoma type, defined by stippled heterochromatin distribution and peculiar huge cells, reacted selectively (p less than 0.05) with anti-phosphokinase C antibody. Anaplastic large cell T-ML reacted with a set of Ber H2, LN-2 and Leu M1. In T-zone lymphomas without hyperplastic follicles, angioimmunoblastic lymphadenopathy with dysproteinemia-type T-ML, lymphoepithelioid cell lymphomas and some pleomorphic lymphomas comprising clear large lymphoma cells, there were many intermingling B cells, and their constitution varied. In some lymphoblastic lymphomas of both the T cell and B-cell type, phenotypes of T cells and B cells were expressed. Consequently, it was shown that paraffin immunohistochemistry was useful for the practical histopathological diagnosis of NHML even in the area where human T-cell leukemia virus type 1 is endemic.

Antibodies, Monoclonal↗

Pathologic diagnosis of mantle cell lymphoma.

Mantle cell lymphoma (MCL) is a clinicopathologic entity with distinctive morphologic and immunophenotypic features and a characteristic cytogenetic abnormality, the t(11;14)(q13;q32). Although MCL was recognized over 30 years ago, a lack of consensus regarding its morphologic features precluded its inclusion into non-Hodgkin's lymphoma (NHL) classification schemes until relatively recently. An accurate diagnosis of MCL is of great importance, since this tumor generally carries a poor prognosis and requires more aggressive and novel treatment regimens. In this article, we briefly overview the clinical features of MCL and then focus on the pathologic diagnosis of MCL, emphasizing morphologic findings and various ancillary techniques useful in the diagnostic workup. Involvement of lymph nodes and other sites, such as the spleen, liver, gastrointestinal tract, Waldeyer's ring, bone marrow, peripheral blood, and cerebrospinal fluid are reviewed. The diagnosis of high-grade variants of MCL is a particular challenge, as these tumors exhibit a broad spectrum of morphologic findings that can be misinterpreted as other types of NHL. The molecular basis of MCL is also briefly reviewed to highlight the biologic role of the t(11;14) and cyclin D1 overexpression in this tumor and the value of immunophenotypic and molecular methods for their detection as diagnostic aids.

Cytogenetics↗

[Characteristics of the spread pattern in esophageal carcinoma].

The correlation of spread pattern with various clinical and histopathological factors was studied using macroscopic and microscopic findings of 284 patients who had undergone resection for esophageal carcinoma without pre-operative treatment. Macroscopic evaluation were made according to new classification proposed by the Japanese Pathological Research Committee for esophageal carcinoma. The location of primary tumour, length, macroscopic type, the depth of penetration, and extranodal lymphatic and vessel permination of cancer cells (Exn-LV-Pm) had a correlation with the lymph node metastasis and the prognosis. The protruded type, ulcerative and localized type of tumor had a comparatively low lymph nodes metastases. On the other hand, ulcerative and infiltrative type, diffusely type of tumor had high incidence of lymph node metastasis. Histopathological findings for small size and non-penetrating of tumor shows variant histological type: e.g. undifferentiated carcinoma (3), adeno-squamous (3), P/D squamous cell carcinoma (8), M/D sq. cell ca. (12), W/D sq. cell ca. (4). The penetrating small tumour was almost M/D and W/D squamous cell carcinoma. For the purpose to clarify the pattern of lymph stream for esophageal carcinoma, we examined the status of lymph node metastasis of comparatively early carcinoma (sm. or mp.) relating to the site of primary tumor. Tumor in the middle esophagus drained into the mediastinal lymph nodes. Tumor in lower esophagus drained only into the abdominal lymph nodes. Microscopic examination of extranodal lymphatic and vessel permeation (Exn-LV-Pm) for dissected lymph nodes was carried out 71 cases. The positive cases of Exn-LV-Pm was 33%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

An approach to yeast classification by mapping mitochondrial DNA from Dekkera/Brettanomyces and Eeniella genera.

Sequences hybridizing to mitochondrial DNA probes from Saccharomyces cerevisiae have been mapped in six mitochondrial genomes from the Dekkera/Brettanomyces yeasts and in mtDNA from the closely related Eeniella nana. Sequence order for the 34.5 kbp mtDNA of E. nana is identical to that for mtDNAs from B. custersianus (28.5 kbp) and B. naardenensis (41.7 kbp) thereby suggesting that the former yeast is affiliated with the latter two species. A closer relationship is suggested for D. intermedia and D. bruxellensis as mtDNAs from these yeasts, 73.2 and 85.0 kbp respectively, have the same sequence order and mostly common restriction endonuclease sites. Differences between the two molecules are reminiscent of those found in mtDNA polymorphisms of S. cerevisiae strains thereby suggesting that the two Dekkera yeasts are variants of a single species. An unusual feature of the Dekkera species mtDNA is an inversion of the cytochrome b hybridizable region relative to the LrRNA sequence. Likewise mtDNA from B. anomalus (57.7 kbp) has an inversion of the cytochrome oxidase subunit 1 sequence with respect to the LrRNA sequence. By contrast the largest mtDNA (101.1 kbp) from B. custersii has the cytochrome b and LrRNA sequences in the same orientation. In addition hybridizable regions in this mtDNA are found in three clusters that are separated by several thousand base pairs of sequence deficient in restriction endonuclease sites. This observation together with the low guanine and cytosine content of the mtDNA suggests that the regions separating the sequence clusters are mostly adenine and thymine residues.

Chromosome Mapping↗

Radix entomolaris: identification and morphology.

The Royal Dental College, Copenhagen, houses an extensive collection of human teeth, extracted in Denmark. At present, the collection includes 398 permanent mandibular molars with a root complex containing a lingually-located supernumerary root. This macrostructure is called radix entomolaris (RE). By analyzing the large number of available specimens it was possible to establish uniform and precise criteria for the identification of RE on M1 inf, M2 inf, and M3 inf. The analyses included separate as well as non-separate RE. The representation of the RE variants according to tooth types was mapped. Furthermore, the following relevant clinical variables with respect to RE were registered: degree of separation, divergence, apical bend, apical gracility, and fusion. Because of the nature of the material, the investigation was mostly qualitative and non-metric. The results should be of interest to clinical dentists, dental morphologists, and dental anthropologists.

Classification↗

Combined histopathological and molecular cytogenetic stratification of medulloblastoma patients.

This study examined the utility of stratifying children with medulloblastomas by a combination of refined histopathological classification and molecular cytogenetic evaluation. Detailed histopathological classification of tumors from a cohort of patients (n = 87) composed mainly of children entered into the International Society of Pediatric Oncology (SIOP)/United Kingdom Children's Cancer Study Group PNET3 trial (n = 65), included identification of the large cell/anaplastic phenotype. Fluorescence in situ hybridization was used to detect chromosome 17 abnormalities, losses of 9q22 and 10q24, and amplification of the MYCC and MYCN oncogenes. The large cell/anaplastic phenotype, which was present in 20% of medulloblastomas, emerged as an independent prognostic indicator. Loss of 17p13.3 (38% of medulloblastomas) was found across all of the histopathological variants, whereas MYCC/MYCN amplification (6%/8% of medulloblastomas) was significantly associated with the large cell/anaplastic phenotype. Both of these genetic abnormalities emerged as prognostic indicators. Loss of 9q22 was associated with the nodular/desmoplastic medulloblastoma variant, whereas loss of 10q24 was found in all of the variants. Together with metastatic tumor at presentation, the large cell/anaplastic phenotype, 17p13.3 loss, or high-frequency MYC amplification defined a high-risk group of children whose outcome was significantly (P = 0.0002) poorer than a low-risk group without these tumor characteristics. Combined evaluation of novel histopathological features and molecular cytogenetic abnormalities promises to allow stratification of patients with medulloblastoma, such that those likely to be cured will be spared the side effects of maximal therapy, which can be targeted at those with aggressive disease.

Cerebellar Neoplasms↗

Fibromyxoma of bone: a case report and review of the literature.

In this study, a case of fibromyxoma of the proximal femur in a 59-year old woman is reported. The classification of this rare bone tumour is still a matter of debate and some investigators have suggested that these lesions represent a degenerative form of fibrous dysplasia. Some authors make a further distinction between fibromyxoma and myxoma of bone. In a review of 23 cases of fibromyxoma and five cases of myxoma, no differences in clinical, radiographic and biologic behaviour between fibromyxoma and myxoma were found. Apart from the age at diagnosis, the most important difference between fibromyxoma and myxoma was the degree of myxoid matrix. Therefore, we suggest that extragnathic myxoma is a regressive variant of extragnathic fibromyxoma and should be termed as the same entity. In contrast to monostotic fibrous dysplasia fibromyxoma / myxoma often causes pain and presents as a Lodwick IC lesion with a soft tissue mass. Therefore, fibromyxoma / myxoma should be distinguished from fibrous dysplasia because of its different clinical and radiographic features.

Biopsy, Needle↗

[Computerized tomography studies of normal morphology and volumetry of parenchymatous epigastric organs in humans].

Variations in the area and dimensions of the liver and spleen in the craniocaudal direction show a similar behaviour despite individual differences in the size and shape of the organs. The liver has its largest areal extent in the upper half of the organ. In the case of the spleen, it is not possible for the largest areal extent to be assigned to a particular region of the organ. The 5-type liver classification of FROMMHOLD and KOISCHWITZ (1982) provided the basis for a study of the frequency distribution of those types among a total of 116 organs. Type 2 (location of the greater part of the liver to the right of the vertebral column) was found to be the most frequent type, whereas type 5 (left lobe of the liver larger than the right one) could not be found. Of the 183 splenic organs included in these studies, 21% showed lobulation and 6%, an accessory spleen. The morphological studies of 334 adrenal glands enabled the most frequent variants of form to be represented summarily. The determination of liver dimensions, which was done on 37 organs, yielded a mean value of 16.6 cm for the craniocaudal extent, 15.5 cm for the dorsoventral extent, and 16.6 cm for the lateromedial extent. From the examinations performed on 38 individuals it was possible to determine a mean value of 11.1 cm for the craniocaudal extent of the spleen, 11.8 cm for the anatomical length of the spleen, 10.4 cm for the width of the spleen, and 4.2 cm for the thickness of the spleen. The mean value of the width of pancreas was 20.5 mm at the head, 19.6 mm at the corpus, and 18 mm at the tail. The mean length of pancreas was of the order of 129 mm. These results were obtained from examinations made on 96 pancreatic organs. Evaluation of a total of 200 computer tomograms yielded mean values of 22 mm for the length. 14 mm for the width, and 5 mm for the leg thickness of the left adrenal gland. The respective mean values obtained for the right adrenal gland were 28 mm, 9 mm, and 4 mm respectively. Determination of the volume of liver on 37 organs yielded a mean value of 1,331 cm3. For the spleen, examinations performed on 38 organs showed the mean volume to be in the order of 169 cm3. For the volume of pancreas, a mean value of 40.4 cm3 was determined.

Adrenal Glands↗

[Diagnosis of swine dysentery and spirochaetal diarrhea. 2. Effort of macrorestriction analysis for differentiation of intestinal Serpulina relative to determination by culture-biochemical markers following species classification].

Genotypic differentiation by means of macrorestriction fragment profile analysis using Mlul restriction enzyme was carried out differentiating 41 Serpulina field strains from swine (38), dog (2) and a rat as well as ten type and reference strains into 40 electrophoretic types. A dendrogram was created using the average linkage between groups method. At a level of 50% similarity the patterns could be divided into six groups that roughly corresponded to the results yielded by cultural and biochemical methods formerly (FELTRUP et al. 1999). Five of these clusters corresponded to the five known porcine Serpulina species, one cluster contained the S. pilosicoli isolates from dog and rat included in this study. Interestingly all nine investigated indole negative, strongly haemolytic isolates were clustered together in one group with the S. hyodysenteriae strains, so that incidence of indole negative variants of S. hyodysenteriae was confirmed. Because of being grouped together with two S. intermedia isolates, the suitability of B 256 as S. innocens type strain is--in accord to investigations carried out by PETTERSSON et al (1996)--called in question.

Animals↗

Chromophobe renal cell carcinoma: analysis of 61 cases.

BACKGROUND: Chromophobe renal cell carcinoma (CRCC) is often associated with a favorable prognosis. However, to the authors' knowledge, only few clinical data are available regarding this variant of tumor. In the current study, the authors report their experience with CRCC over the last 14 years. METHODS: Since 1989, 61 patients have been treated at the study institution for CRCC. Tumor characteristics and patient outcome were analyzed retrospectively. Data were obtained from the patients' medical records. RESULTS: The mean age of the patients was 58 years. Of the 61 tumors, 68.8% were discovered incidentally. The mean tumor size was 6.9 cm. Fifty-seven patients (93.4%) were treated with radical nephrectomy and 4 patients (6.6%) underwent partial nephrectomy. According to the 1997 TNM classification, the pathologic tumor stage was T1 in 65.6% of cases, T2 in 31.1% of cases, and T3a in 3.3% of cases. All tumors were staged as N0M0. Nuclear grade was low (1 or 2) in 88.5% of cases. In no case of CRCC was a sarcomatoid component observed. At a mean follow-up of 49.5 months (range, 5-135 months), no patient had experienced tumor recurrence or disease progression, and none had died of renal carcinoma. CONCLUSIONS: In the authors' experience, CRCC carries an excellent prognosis, possibly due to the high rate of low-stage and low-grade tumors.

Adult↗

Multiplex RT-PCR assay for the detection of major fusion transcripts in Taiwanese children with B-lineage acute lymphoblastic leukemia.

BACKGROUND: The classification of B-lineage acute lymphoblastic leukemia (ALL) by specific chromosomal translocations may have prognostic implications. Reverse transcriptase-polymerase chain reaction (RT-PCR) assay is a useful tool for the detection of fusion transcript resulting from specific chromosomal translocation of the leukemic cells. In general, fusion transcripts are determined individually, a process which is labor intensive in order to detect all major fusion transcripts. PROCEDURE: We use a multiplex RT-PCR assay to detect both the CML- and ALL-type BCR-ABL transcripts of the t(9;22), all described variants of the E2A-PBX1 transcripts of t(1;19), the MLL-AF4 transcripts of t(4;11), and all described variants of TEL-AML1 (also termed ETV6-CBFA2) of the cryptic t(12;21) in 165 leukemic samples at diagnosis. RESULTS: The study yielded a completely concordant result with those obtained by the individual RT-PCR assay. In this cohort of Taiwan children, the relative frequencies of the four translocations of B-lineage ALL were as following: 6% with ALL-type t(9;22)/BCR-ABL, 7% t(1;19)/E2A-PBX1, 3% t(4;11)/MLL-AF4, and 18% t(12;21)/TEL-AML1, comparable to those in the Western countries. CONCLUSION: Multiplex RT-PCR assay is an efficient, sensitive, accurate, and cost-effective diagnostic tool, which will likely improve our ability in accurately and rapidly risk-stratifying children with ALL.

Adolescent↗

Mastocytosis: current concepts in diagnosis and treatment.

Mastocytosis consists of a group of disorders characterized by a pathologic increase in mast cells in tissues including skin, bone marrow, liver, spleen, and lymph nodes. Mastocytosis is a rare disease. Because of this, general practitioners have limited exposure to its clinical manifestations, diagnosis, classification, and management. Diagnosis of mastocytosis is suspected on clinical grounds and is established by histopathologic examination of involved tissues such as skin and bone marrow. The most common clinical sign of mastocytosis is the presence of typical skin lesions of urticaria pigmentosa. Most patients experience symptoms related to mast cell mediator release, and prevention of the effects of these mediators on tissues constitutes the major therapeutic goal in the management of mastocytosis. Despite recent advances in knowledge about the pathophysiology, diagnosis, and classification of mastocytosis, a curative treatment for mastocytosis does not now exist. Management of patients within all categories of mastocytosis includes: (1) a careful counseling of patients (parents in pediatric cases) and care providers, (2) avoidance of factors triggering acute mediator release, (3) treatment of acute mast cell mediator release, (4) treatment of chronic mast cell mediator release, and if indicated (5) an attempt to treat organ infiltration by mast cells. The goal of this manuscript is to provide an overview of the mediators produced and released by mast cells, the diagnostic criteria for the different variants of mastocytosis, and the treatment options currently available.

Humans↗

Duplication of male urethra.

Male urethral duplication is an unusal anomaly with many variants including complete duplication from the bladder to the glans penis as well as incomplete and abortive forms. Two cases are presented of duplication of the male urethra of the epispadiac incomplete type. A chart has been constructed to facilitate categorization of the various forms of urethral duplication in the male.

Adult↗

Prevalence and prognostic significance of tall cell variant of papillary thyroid carcinoma.

The aim of this study was to assess the prevalence, prognostic factors, and long-term outcome of tall cell variant (TCV) in comparison with the conventional forms of papillary thyroid carcinoma (PTC). A total of 945 patients with thyroid cancer were treated and followed up from 1960 to 1998. Pathologic review was performed in 778 patients (84%) of the cohort. Of these, 674 had PTC: 503 (74%) had conventional form (CF); 56 (8%), TCV; and 155 (17%), other variants of PTC. Tall cell variant was associated with tumors of larger size (P < .001), bilaterality (P < .02), multifocality (P < .04), and extrathyroidal invasion (P < .001). Treatment was similar in both groups, but neck dissection was performed more frequently in patients with TCV (P < .04). The 10-year overall and event-free survival rates were, respectively, 90% and 85% in the CF versus 79% and 67% in the TCV group (P < .001). Histologic subtype did not have an effect on clinical outcome after multivariate analysis, the most relevant factors being age, involved nodes, or the "Metastasis, Age, Completeness, Invasion, Size" classification after multivariate analysis. In this large cohort of patients, TCV represents 8.3% of PTC, and it is a more aggressive form of PTC than CF because of the higher stage and increased grade.

Adolescent↗