RESUMEN
CONTEXT: The cytologic features of carcinoid tumor of the lung are well described. Nevertheless, some carcinoids may be difficult to distinguish from small cell carcinomas. OBJECTIVE: To correlate the cytologic features of individual cases of carcinoid tumor of the lung in fine-needle aspiration specimens in the College of American Pathologists Non-Gynecologic Cytology Program with the frequency of misclassification as small cell carcinoma. DESIGN: We reviewed 1100 interpretations from 26 different cases of carcinoid tumor in lung fine-needle aspiration specimens in the College of American Pathologists Non-Gynecologic Cytology Program and correlated the cytologic features with the performance in the program. RESULTS: Cases were divided into those that were frequently misclassified as small cell carcinoma (at least 20% of the responses, 19 cases) and those that were infrequently misclassified as small cell carcinoma (<10% of all responses, 7 cases). All cases had areas with classic features of carcinoid tumor. Cases were reviewed independently by 3 cytopathologists specifically looking for cytologic features that might be responsible for misclassification as small cell carcinoma. All 7 cases that were infrequently misclassified consisted of numerous monotonous well-preserved tumor cells that were either entirely round or were a mixture of round and spindle-shaped cells. Six of 7 cases showed a prominent streaming vascular pattern with tumor cells attached to the endothelial cell core. In contrast, cases that were frequently misclassified had 1 of 6 patterns that were not seen in cases that were rarely misclassified. These 6 patterns were: (1) poorly preserved and pale-staining cells with fine chromatin and a suggestion of molding (5 cases); (2) numerous large, well-preserved, spindle-shaped cells (2 cases); (3) numerous cells varying markedly in both size and shape (both round and spindle-shaped cells), with a common finding of degenerated, smudgy, small round and spindle-shaped cells (9 cases); (4) hypocellular specimens (8 cases); (5) obscuration of cells by blood (2 cases); and (6) tumor cells present predominantly in groups, with few isolated cells (8 cases). In none of these cases were mitoses or true necrosis identified. CONCLUSIONS: Frequent misclassification of carcinoid tumor as small cell carcinoma in lung fine-needle aspiration specimens in this program correlates strongly with specific cytologic features, some of which are common in small cell carcinoma (fine chromatin, molding, smudgy chromatin) and others that are not (spindle-shaped cells). In addition, hypocellular specimens or specimens with cellular obscuration performed poorly, along with specimens exhibiting absence of the commonly described carcinoid feature of streaming vascularity. Awareness of these patterns may aid in avoiding misdiagnosis.
Asunto(s)
Tumor Carcinoide/patología , Carcinoma de Células Pequeñas/patología , Competencia Clínica , Neoplasias Pulmonares/patología , Patología Quirúrgica/métodos , Biopsia con Aguja Fina , Tumor Carcinoide/clasificación , Carcinoma de Células Pequeñas/clasificación , Diagnóstico Diferencial , Errores Diagnósticos/prevención & control , Humanos , Neoplasias Pulmonares/clasificación , América del Norte , Patología Quirúrgica/educación , Patología Quirúrgica/normas , Sociedades MédicasRESUMEN
CONTEXT: Conventional Papanicolaou (Pap) test slides of high-grade squamous intraepithelial lesions (HSILs) that are frequently misdiagnosed are known to have relatively few dysplastic cells. Whether this is true of cases of HSIL in ThinPrep Pap Test specimens is not known. OBJECTIVE: To determine if cases of HSIL in ThinPrep specimens that are frequently missed have relatively few dysplastic cells. DESIGN: The cytologic features of 16 ThinPrep cases of HSIL that performed poorly in the College of American Pathologists Interlaboratory Comparison Program were compared with 22 ThinPrep Pap Test cases that performed extremely well. RESULTS: Significantly more cases that performed poorly had fewer than 250 dysplastic cells (13/16) than cases that performed well (3/22) (P <.001). CONCLUSION: ThinPrep Pap Test cases with a diagnosis of HSIL that performed poorly in this program had significantly fewer dysplastic cells than those that performed well.
Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias del Cuello Uterino/patología , Errores Diagnósticos , Femenino , Humanos , Prueba de Papanicolaou , Garantía de la Calidad de Atención de Salud , Estados Unidos , Displasia del Cuello del Útero/patología , Frotis Vaginal/métodos , Frotis Vaginal/normasRESUMEN
CONTEXT: Although the cytologic features of squamous cell carcinoma in ThinPrep specimens are well known, whether these features are different in cases that are easily identified than in cases that are more difficult to identify is not known. OBJECTIVE: To determine the cytologic features of squamous cell carcinoma in ThinPrep specimens that are easy to identify versus those that are difficult. DESIGN: The cytologic features of 6 cases of squamous cell carcinoma that performed poorly in the College of American Pathologists Interlaboratory Comparison Program were compared with 14 cases that performed extremely well. RESULTS: After evaluation of multiple criteria, 7 different cytologic features were analyzed based on review by a consensus panel blinded to the performance of the cases. The feature that was most strongly associated with cases that performed poorly was the presence of Trichomonas vaginalis (5/6 [83%] vs 0/14; P <.001). The presence of marked nuclear pleomorphism was more common in cases that performed well (4/14 [28%] vs 0/6; P =.27), but was not significant. The number of tumor cells, the number of normal cells, and the presence of keratinization, pleomorphism, nucleoli, and diathesis were not significant. The most common misdiagnosis after Trichomonas vaginalis was reparative change. CONCLUSIONS: The presence of Trichomonas is characteristic of cases of squamous cell carcinoma in ThinPrep slides that are often misdiagnosed in this program. While Trichomonas is identified by participants in some of these cases, a significant percentage of participants interpreted the findings as reparative, without identifying the organism. These results emphasize the importance of distracting factors, whether identified or not, in evaluating gynecologic cytology.
Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias del Cuello Uterino/patología , Frotis Vaginal , Carcinoma de Células Escamosas/complicaciones , Carcinoma de Células Escamosas/diagnóstico , Núcleo Celular/ultraestructura , Errores Diagnósticos , Femenino , Humanos , Garantía de la Calidad de Atención de Salud , Vaginitis por Trichomonas/complicaciones , Vaginitis por Trichomonas/patología , Neoplasias del Cuello Uterino/complicaciones , Neoplasias del Cuello Uterino/diagnóstico , Frotis Vaginal/estadística & datos numéricosRESUMEN
CONTEXT: Adenocarcinoma in situ of the cervix is a recently recognized interpretation in the Bethesda 2001 system. Although specific morphologic criteria have been published, recognizing this entity is still difficult. OBJECTIVE: To compare pathologists' ability to correctly identify and categorize adenocarcinoma in situ with their ability to identify and categorize adenocarcinoma, high-grade squamous intraepithelial lesion, and squamous cell carcinoma. DESIGN: Pathologists' reviews in the 2001 and 2002 College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology Program, an interlaboratory comparison program for gynecologic cytology, were examined. Cases were usually reviewed by multiple pathologists. False-negative rates, the percentage of reviews with exact agreement with reference interpretations, and the percentage of cases in which all reviews were in exact agreement with the reference interpretation for adenocarcinoma in situ, adenocarcinoma, high-grade squamous intraepithelial lesion, and squamous cell carcinoma were compared. RESULTS: A total of 213 reviews of cases categorized as adenocarcinoma in situ were compared with 2821 reviews of adenocarcinoma, 7535 reviews of high-grade squamous intraepithelial lesion, and 1886 reviews of squamous cell carcinoma. The false-negative rate for adenocarcinoma in situ (11.7%) was significantly higher than that for high-grade squamous intraepithelial lesion (4.6%, P <.001) and squamous cell carcinoma (3.3%, P <.001) but not for adenocarcinoma (8.9%, P =.16). Of all the reviews of adenocarcinoma in situ cases, 46.5% were interpreted specifically as adenocarcinoma in situ, compared to 72.2% of reviews of adenocarcinoma, 73.2% of high-grade squamous intraepithelial lesion, and 75.1% of squamous cell carcinoma. No individual case of adenocarcinoma in situ was always specifically recognized as adenocarcinoma in situ; 26.5% of cases of adenocarcinoma were specifically recognized as such in all reviews. Findings were similar with and without the inclusion of high-grade squamous intraepithelial lesion/carcinoma, not otherwise specified, as an acceptable review interpretation for cases of adenocarcinoma, squamous cell carcinoma, and high-grade squamous intraepithelial lesion. CONCLUSION: These data from expert-referenced and biopsy-proven cases suggest that adenocarcinoma in situ is not as easily recognized or categorized as other serious diagnoses.