Intraoperative scrape cytology: comparison with frozen sections, using receiver operating characteristic (ROC) curve

Role of scrape cytology smear preparation in the diagnosis of ovarian masses-utility and pitfalls

BACKGROUND

Scrape cytology technique is useful for rapid intraoperative diagnosis of ovarian mass lesions that acts as an adjunct to frozen section examination. Though ovaries can be accessed by laparoscopy and USG guided FNAC, there are controversial reports regarding the safety of these procedures. The present study has been designed to evaluate the role of scrape cytology in a variety of ovarian mass lesions.

OBJECTIVES

To study the cyto-morphology of ovarian mass lesions and to evaluate the role of scrape cytology technique in correctly diagnosing the ovarian lesions taking histopathological diagnosis as gold standard.

MATERIAL AND METHODS

This is a prospective observational study done on 61 ovarian mass lesions as received from the Obstetrics and Gynecology department of our Institution.

RESULT

Out of 61 cases, 58 (95.08%) cases were correctly diagnosed with respect to categorization and typing. The age ranged from 14 to 65 years with the mean age being 38.1 years. On histopathology, out of 61 cases, 39 (63.93%) were epithelial along with sub categorization of benign, borderline, and malignant, 13 (22.9%) were germ cell tumors, 5(8.19%) were sex cord stromal tumors, 3 (4.91%) were hemorrhagic cysts and the remaining 1 (1.63%) was massive ovarian edema. Thus, on comparing with histopathology, the sensitivity and specificity of scrape cytology technique were 93.55% and 96.67%, and the diagnostic accuracy was 95.08%.

CONCLUSION

Scrape cytology of ovarian lesions can give quick and reliable results. Also, proper training of cytopathologists chiefly regarding the sampling technique, gross presentation of ovarian lesions and interpretation of scrape cytology smears is needed. Further studies to provide standard guidelines and reporting criteria will prove to be helpful.

SARS-CoV-2 RNAemia and Disease Severity in COVID-19 Patients

OBJECTIVE

The clinical implications of SARS-CoV-2 RNA viremia in blood (RNAemia) remain uncertain despite gaining more prognostic implications for coronavirus disease 2019 (COVID-19). However, the clinical relevance of SARS-CoV-2 RNAemia has not been well documented.

METHODS

We conducted a cohort study on 95 confirmed COVID-19 patients and explored the prospects with evidence of SARS-CoV-2 RNAemia in association with various clinical characteristics. We performed reverse transcription-polymerase chain reaction and studied the risk factors of SARS-CoV-2 RNAemia using logistic regression analysis.

RESULTS

The presence of SARS-CoV-2 RNAemia in critical or fatal cases was the highest (66.7%), followed by severe (12.5%) and mild to moderate (1.7%) in admission samples. SARS-CoV-2 viral RNAemia was detected on admission and 1st week samples; however, RNAemia was not detected on the samples collected on the second week post-symptom onset. Multiple regression analysis showed that the severity of the disease was an independent predictor of RNAemia (p < 0.021), and the Kaplan-Meier survival curve estimated an increased mortality rate in SARS-CoV-2 RNAemia cases (p < 0.001).

CONCLUSIONS

Our study demonstrated that SARS-CoV-2 RNAemia is a predictive risk factor for clinical severity in COVID-19 patients. Hence, we showed that blood RNAemia might be a critical marker for disease severity and mortality.

Accuracy of Real-Time Polymerase Chain Reaction in COVID-19 Patients

Coronavirus disease 2019 (COVID-19) is a mild to severe respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The diagnostic accuracy of the Centers for Disease Control and Prevention (CDC)- or World Health Organization (WHO)-recommended real-time PCR (RT-qPCR) primers in clinical practice remains unproven. We conducted a prospective study on the accuracy of RT-qPCR using an in-house-designed primer set (iNP) targeting the nucleocapsid protein as well as various recommended and commercial primers. The accuracy was assessed by culturing or seroconversion. We enrolled 12 confirmed COVID-19 patients with a total of 590 clinical samples. When a cutoff value of the cycle threshold (C_t) was set to 35, RT-qPCRs with WHO RdRp primers and CDC N1, N2, and N3 primers showed sensitivity of 42.1% to 63.2% and specificity of 90.5% to 100% in sputum, and sensitivity of 65.2% to 69.6% and specificity of 65.2% to 69.6% in nasopharyngeal samples. The sensitivity and specificity of iNP RT-qPCR in sputum and nasopharyngeal samples were 94.8%/100% and 69.6%/100%, respectively. Sputum testing had the highest sensitivity, followed by nasopharyngeal testing (P = 0.0193); self-collected saliva samples yielded better characteristics than oropharyngeal samples (P = 0.0032). Our results suggest that iNP RT-qPCR has better sensitivity and specificity than RT-PCR with WHO (P < 0.0001) or CDC (N1: P = 0.0012, N2: P = 0.0013, N3: P = 0.0012) primers. Sputum RT-qPCR analysis has the highest sensitivity, followed by nasopharyngeal, saliva, and oropharyngeal assays. Our study suggests that considerable improvement is needed for the RT-qPCR WHO and CDC primer sets for detecting SARS-CoV-2. IMPORTANCE Numerous research campaigns have addressed the vast majority of clinical and diagnostic specificity and sensitivity of various primer sets of SARS-CoV2 viral detection. Despite the impressive progress made to resolve the pandemic, there is still a need for continuous and active improvement of primers used for diagnosis in clinical practice. Our study significantly exceeds the scale of previously published research on the specificity and sensitivity of different primers comparing with different specimens and is the most comprehensive to date in terms of constant monitoring of primer sets of current usage. Henceforth, our results suggest that sputum samples sensitivity is the highest, followed by nasopharyngeal, saliva, and oropharyngeal samples. The CDC recommends the use of oropharyngeal specimens, leading to certain discrepancy between the guidelines set forth by the CDC and IDSA. We proved that the oropharyngeal samples demonstrated the lowest sensitivity for the detection of SARS-CoV-2.

Diagnostic Utility and Accuracy of Scrape Cytology in Evaluation of Neoplastic Lesions

Background

Frozen section, intraoperative fine needle aspiration cytology (FNAC) and imprint cytology have been used traditionally by the surgical pathology laboratories for rapid intraoperative diagnosis of tumors. Scrape cytology is a modification of imprint cytology that involves lightly scraping or brushing cells from freshly cut surface of the surgically removed tumor specimens. The present study was carried out to evaluate the utility of scrape cytology in diagnostic evaluation of tumors.

Material and Methods

A prospective study was carried out at a tertiary care teaching hospital in Central India. A total of 50 consecutively received specimens in the Department of Pathology and Laboratory Medicine with clinical or radiological suspicion of neoplasia were included in the study. Scrape smears were prepared from freshly cut surface of tumor specimens received unfixed or in 10% formalin.

Results

Overall, the scrape cytology diagnosis was concordant with final histopathological diagnosis in 48 out of 50 cases with a diagnostic accuracy of 96%. The sensitivity was 90.9% (CI-58.72% to 99.77%) and specificity was 97.4%(CI-86.52% to 99.94%). Positive predictive value and negative predictive value were 90.91% and 97.44%, respectively.

Conclusion

Scrape cytology is a cost-effective and reasonably accurate cytodiagnostic technique for rapid tumor diagnosis. Scrape cytology can be a useful supplementary tool to frozen section, and may be applied for rapid diagnosis where frozen section technique is not available. The material and knowledge obtained from scrape cytology of routinely received histopathological specimens can be utilized as a teaching material and may help unveil diagnostic cytopathological features of infrequent cytologically encountered lesions.

Laboratory management curriculum for cytopathology subspecialty training

Laboratory management should be an integral part of training in pathology residency and fellowships. Herein, we have outlined some basic laboratory management topics a graduating cytopathology fellow should be familiar with. An overview of regulatory agencies that have oversight over laboratory testing, cytopathology laboratory accreditation, pre-analytic, analytic and post-analytic quality assurance, billing/coding, basic statistics, verification/validation of testing, physician credentialing, board certification/maintenance of certification, and malpractice in cytopathology are addressed. This review is by no means all inclusive, but rather a guide to the basic management related topics to be covered during cytopathology subspecialty training.

Role of fine needle aspiration, imprint and scrape cytology in the evaluation of intraoral lesions

Aim:

The primary goal of our study was to evaluate the value and accuracy of fine needle aspiration cytology (FNAC) in the diagnosis of various intraoral lesions and to correlate the cytological diagnosis with final histopathological findings.

Materials and Methods:

Fine needle aspiration was performed in 229 patients presented with different lesions of the oral cavity at our institution. Cytological findings were then compared with final histopathological diagnosis.

Results:

With a male to female ratio of 1.79:1, 229 patients presented with different lesions of the oral cavity were aspirated. Histopathological correlation was available in 86.9% of cases while inadequate material was obtained in 13.1% cases. The diagnostic accuracy of fine needle aspiration in diagnosing benign, pre-malignant and malignant lesions were 95.8%, 84.6% and 97% respectively. Overall the diagnostic accuracy of FNAC in diagnosing intraoral lesions was 94.9% with sensitivity and specificity of 93.2% and 96.8% respectively.

Conclusion:

FNAC of intraoral lesion is recommended as a valuable procedure for the initial evaluation of all intraoral lesions as it is simple, inexpensive, convenient and comfortable to the patient. Moreover, it can offer a rapid and accurate diagnosis for further management of the patient.

Rapid immunocytochemistry with simple heat-induced antigen retrieval technique for improvement in the quality of cytological diagnosis

Rapid immunocytochemistry (ICC) can improve the accuracy of intraoperative cytological diagnoses; however, it is usually applied without heat-induced antigen retrieval (HIAR). We established a HIAR method for rapid ICC and evaluated its efficacy and reliability. Rapidly fixed smear samples were immunostained using 35 antibodies. We compared the results of HIAR by boiling in a pot or heating in an electric kettle. The smears were incubated for 3 min with each primary antibody and immuno-enzyme polymer reagent, and for 1 min with diaminobenzidine solution. HIAR for 1 min using the kettle method yielded the best cellular integrity. For 32 out of the 35 antibodies, results achieved using rapid ICC within 11 min were comparable to that achieved using standard ICC. HIAR was essential for 13 antibodies. For two of the antibodies, HIAR was not required when standard ICC was applied, but consistent staining with rapid ICC was obtained only with HIAR. In conclusion, we established a rapid ICC procedure using a simple HIAR method, which allowed efficient immunostaining of a panel of antigens, including nuclear antigens, within only 11 min. The combined use of this rapid ICC technique with other staining techniques could be useful for improving intraoperative cytological diagnoses.

The diagnostic utility of intraoperative cytology in the management of ovarian tumours

BACKGROUND

The present study was done to evaluate the status of intraoperative cytology as a diagnostic and supportive investigation for ovarian tumours.

MATERIAL AND METHODS

The present study was conducted in the Department of Pathology, Sree Balaji Medical College and Hospital, Chennai, Tamil Nadu, India during a time span of 13 months (June 2011 to June 2012). A prospective investigation was performed on 50 cases of suspected ovarian neoplasms. Imprint smears were made intraoperatively from fresh samples from various representative areas, and they were immediately fixed in 95% ethyl alcohol and stained with the haematoxylin and eosin stain. The results were compared with the final histopathological diagnoses in each case.

RESULTS

There were 20 benign lesions, 4 borderline epithelial neoplasms and 26 malignant tumours according to the final histopathological diagnosis. The overall diagnostic accuracy of imprint cytology has been satisfactory, with those of 90% of the cases correlating with the final diagnoses. Characteristic cytological patterns were noted in various surface epithelial, sex cord stromal and germ cell tumours.

CONCLUSION

Imprint cytology can be used as an adjunct to histopathology for a rapid and an early diagnosis in the operation theatre, particularly in developing countries like ours, where the facility of frozen sections is often not available, since a rapid preliminary diagnosis may help in the surgical management planning.

Melanocytic bronchopulmonary carcinoid tumor in a patient with multiple endocrine neoplasia syndrome type 1: a case report with emphasis on intraoperative cytological findings

We present the cytological features along with histologic and imaging findings of a melanocytic bronchopulmonary carcinoid tumor in a patient with multiple endocrine neoplasia syndrome type 1 (MEN-1). Intraoperative touch preparations of the lung tumor showed single spindle cells and loosely cohesive aggregates of spindle cells with oval to elongated nuclei, "salt and pepper" chromatin pattern and inconspicuous nucleoli. The spindle cells occasionally contained cytoplasmic pigment, which revealed to be melanin by Fontana Masson stain on permanent processed material. Immunohistochemical stains for both synaptophysin and chromogranin were strongly positive in the spindle cells. The findings were consistent with melanocytic bronchopulmonary carcinoid tumor, which is relatively uncommon in MEN-1.

Comparison of conventional, nested, and real-time quantitative PCR for diagnosis of scrub typhus

Orientia tsutsugamushi is the causative agent of scrub typhus. For the diagnosis of scrub typhus, we investigated the performances of conventional PCR (C-PCR), nested PCR (N-PCR), and real-time quantitative PCR (Q-PCR) targeting the O. tsutsugamushi-specific 47-kDa gene. To compare the detection sensitivities of the three techniques, we used two template systems that used plasmid DNA (plasmid detection sensitivity), including a partial region of the 47-kDa gene, and genomic DNA (genomic detection sensitivity) from a buffy coat sample of a single patient. The plasmid detection sensitivities of C-PCR, N-PCR, and Q-PCR were 5 × 10(4) copies/μl, 5 copies/μl, and 50 copies/μl, respectively. The results of C-PCR, N-PCR, and Q-PCR performed with undiluted genomic DNA were negative, positive, and positive, respectively. The genomic detection sensitivities of N-PCR and Q-PCR were 64-fold and 16-fold (crossing point [Cp], 37.7; 426 copies/μl), respectively. For relative quantification of O. tsutsugamushi bacteria per volume of whole blood, we performed real-time DNA PCR analysis of the human GAPDH gene, along with the O. tsutsugamushi 47-kDa gene. At a 16-fold dilution, the copy number and genomic equivalent (GE) of GAPDH were 1.1 × 10(5) copies/μl (Cp, 22.64) and 5.5 × 10(4) GEs/μl, respectively. Therefore, the relative concentration of O. tsutsugamushi at a 16-fold dilution was 0.0078 organism/one white blood cell (WBC) and 117 organisms/μl of whole blood, because the WBC count of the patient was 1.5 × 10(4) cells/μl of whole blood. The sensitivities of C-PCR, N-PCR, and Q-PCR performed with blood samples taken from patients within 4 weeks of onset of fever were 7.3% (95% confidence interval [CI], 1.6 to 19.9), 85.4% (95% CI, 70.8 to 94.4), and 82.9% (95% CI, 67.9 to 92.8), respectively. All evaluated assays were 100% specific for O. tsutsugamushi. In conclusion, given its combined sensitivity, specificity, and speed, Q-PCR is the preferred assay for the diagnosis of scrub typhus.

Comparison of conventional, nested, and real-time PCR assays for rapid and accurate detection of Vibrio vulnificus

We conducted a prospective study to target toxR in the blood of patients with skin and soft tissue infections who were admitted to four tertiary hospitals to assess the clinical usefulness of real-time quantitative PCR (Q-PCR) as a diagnostic technique. We performed conventional PCR (C-PCR), nested PCR (N-PCR), and Q-PCR assays and compared the results to those obtained using the "gold standard" of microbiological culture. The lower detection limit for the Q-PCR assay was 5 x 10(0) copies/microl. By use of blood samples of patients with skin and soft tissue infections, the sensitivities of the C-PCR and N-PCR assays against the target toxR gene of V. vulnificus as diagnostic tools were determined to be 45% and 86%, respectively. The C-PCR and N-PCR assays had specificities of 100% and 73%, respectively. When we adopted a crossing-point (cp) cutoff value of <38 cp as a positive result, the Q-PCR assay had 100% sensitivity and specificity. Q-PCR to detect V. vulnificus-specific genes is not only the most sensitive and specific of the techniques but also the most rapid diagnostic method. Therefore, the appropriate application of the Q-PCR assay using blood is useful for the rapid diagnosis and subsequent treatment of V. vulnificus sepsis.

Higher diagnostic accuracy with the ThinPrep method in a simulated intraoperative environment

OBJECTIVE

To compare the accuracy of intraoperative fine needle aspiration cytology samples prepared by the ThinPrep method to conventional cytological methods. Specimen adequacy and turn around time (TAT) were also assessed.

METHODS

Fifty consecutive fresh tumours submitted for histological analysis were aspirated and each prepared as follows: (i) direct smear with H&E stain, (ii) direct smear with Pap stain, (iii) ThinPrep slide with H&E stain, and (iv) ThinPrep slide with Pap stain. The slides were randomly distributed to three cytopathologists for interpretation. The quality of the preparation, the diagnosis and the time needed for interpretation were recorded.

RESULTS

Accuracy was measured as the percentage of absolute agreement between the cytological and the histopathological diagnoses of the lesions. Histologically, there were 43 malignant and six benign lesions and one atypical lipoma. The TAT began when the slides/cytolyte specimens arrived at the lab and ended with the pathologist's diagnosis.

CONCLUSIONS

In terms of accuracy and specimen adequacy, ThinPrep slides with Pap stain is the best procedure. This advantage however is offset by the longer testing time.

Intraoperative Imprint Cytology in Assessment of Sentinel Lymph Nodes and Lumpectomy Surgical Margins

Intraoperative imprint cytology (IIC) in the assessment of sentinel lymph nodes (SNs) allows immediate, cost-effective axillary lymph node dissection. IIC diagnosis is accurate in up to 100% of grossly abnormal SNs. Despite overall low sensitivity for grossly negative SNs, the benefits of immediate complete axillary lymph node dissection offset the increased risk of missing micrometastases or loss of isolated tumor cells (ITCs) by performing frozen section. IIC of the lumpectomy margins is rapid, accurate, and cost effective. It allows re-excision during initial surgery if needed with better cosmetic result. It is a useful adjunct to, and frequently a replacement for frozen section in many centers. Cytopathologists must familiarize themselves with both advantages and pitfalls of IIC to avoid errors.

Diagnostic accuracy of frozen section diagnosis of the adnexal mass: a metaanalysis

BACKGROUND

Frozen section diagnosis is a diagnostic procedure for the assessment of the adnexal mass during surgery. The purpose of the present study was to perform a systematic review of the literature on the accuracy of frozen section diagnosis in the assessment of the adnexal mass.

METHODS

We performed a computerized Medline and EMBASE search to identify all registered articles published between January 1966 and June 2003, comparing frozen section diagnosis of ovarian pathology to the final histopathological diagnosis. For each study, we calculated the prevalence of malignant and borderline tumors, and the sensitivity and specificity of the frozen section diagnosis using the final histopathological diagnosis as reference. We performed the calculations in two ways. In the first analysis, tumors that were found to be borderline were considered as malignant in the 2 x 2 table. In the second analysis, tumors that were found to be borderline were considered as benign in the 2 x 2 table.

RESULTS

Eighteen studies were included for analysis. When the diagnosis borderline was classified as malignant, the sensitivity of frozen section diagnosis varied between 65% and 97%, and the specificity between 97% and 100%. When the diagnosis borderline was considered to be benign, the sensitivity varied between 71% and 100%, for a specificity varying between 98.3% and 100%.

CONCLUSION

The accuracy of frozen section diagnosis for the assessment of the ovarian mass is good, with acceptable sensitivities for almost perfect specificities. Future studies on patient preferences for the different outcomes as well as economic analysis are needed for definite position of this diagnostic technique.

Immunostaining of cytology smears: a comparative study to identify the most suitable method of smear preparation and fixation with reference to commonly used immunomarkers

As an extension of our previous study (Shidham et al., Acta Cytol 2000;44:1015-1022), we evaluated the interference by methods of cytology smear preparation on the immunoreactivity of cytokeratin-7, cytokeratin-20, estrogen receptor, progesterone receptor, chromogranin, synaptophysin, and vimentin. Scrape cytology smears of 34 fresh specimens submitted for intraoperative consultation were studied. They were processed by three different methods--A: wet-fixed in 95% ethanol; B: air-dried saline rehydrated smears fixed in alcoholic formalin; and C: air-dried saline rehydrated smears fixed in 95% ethanol with 5% acetic acid. The intensity scores of immunostaining were estimated semiquantitatively and compared with corresponding formalin-fixed paraffin-embedded tissue sections (FPTS). Except vimentin, all immunomarkers showed higher intensity scores with method A or B than with method C. Vimentin showed the best results with method A. Our results indicate that the immunoreactivity pattern with each immunomarker is affected by the method of cytology smear processing. Most importantly, method C, which is the desired choice for cytomorphological staining, was not suitable for immunostaining.

Improved immunohistochemical evaluation of micrometastases in sentinel lymph nodes of cutaneous melanoma with 'MCW melanoma cocktail'--a mixture of monoclonal antibodies to MART-1, Melan-A, and tyrosinase

BACKGROUND

MART-1, Melan-A, and Tyrosinase have shown encouraging results for evaluation of melanoma micrometastases in sentinel lymph nodes, as compared to conventionally used S-100 protein and HMB-45. To achieve higher sensitivity, some studies recommend evaluation of three sections, each at intervals of 200 micron. This would mean, routine staining of three adjacent sections in each of the three clusters at intervals of 200 micron, requiring nine slides resulting in added expense. If a cocktail of these antibodies could be used, only one section would be required instead of three generating significant cost savings.

METHODS

We prepared a combination of monoclonal antibodies to these three immunomarkers in optimized dilutions (MART-1, clone M2-7C10, dilution 1:500; Melan-A, clone A103, dilution 1:100; and Tyrosinase, clone T311, dilution 1:50) and designated it as 'MCW melanoma cocktail'. Formalin-fixed paraffin-embedded tissue sections of sentinel lymph nodes from patients with cutaneous melanoma, without macro-metastases were evaluated with this cocktail.

RESULTS

Melanoma micrometastases were easily detectable with the cocktail in 41 out of 188 slices (8/24 cases). The diagnostic accuracy amongst five pathologists did not show statistically significant difference. Out of 188 slices, 78 had adjacent sections immunostained individually with MART-1 and Melan-A during our previous study. Of these 78 slices, 21 were positive for melanoma micrometastases with MART-1 and Melan-A individually. However, the adjacent section of these slices immunostained with the cocktail detected metastases in four additional slices. Thus, MART-1 and Melan-A could not detect melanoma micrometastases individually in 16% (4/25) of slices positive with the cocktail. Benign capsular nevi were immunoreactive for the cocktail in 4.8% (9/188) slices. All 81 slices of negative test controls (sentinel lymph nodes of mammary carcinoma) were interpreted correctly as negative for melanoma micrometastases.

CONCLUSIONS

The melanoma cocktail facilitated easy interpretation of melanoma micrometastases in sentinel lymph nodes with high interobserver agreement. There was improvement in detection rate with the cocktail as compared to MART-1 and Melan-A individually. Furthermore, this approach facilitates cost savings.

Scrape cytology of the ovaries: potential role in intraoperative consultation of ovarian lesions

Intraoperative diagnosis of ovarian lesions can be achieved by gross examination with the help of frozen sections and/or cytologic examination. Various cytologic techniques, including imprint, fine-needle aspiration, and scrape, may be used. In this study, we evaluated the application of scrape cytology in the diagnosis of ovarian lesions occurring during a 16-mo period at one institution. The cytologic diagnosis was primarily based on findings in air-dried, Diff-Quik-stained smears in correlation with clinical and intraoperative findings. In total, 131 histologically proven ovarian lesions, including 13 nonneoplastic lesions, 47 benign tumors, 17 epithelial tumors of low malignant potential (LMP), and 54 malignant tumors (35 primary, 1 leukemia, and 18 metastases), were cytologically examined. The accuracy of scrape cytology was 95% in the benign, 47% in the LMP, and 98% in the malignant group. In the LMP group, the false-negative rate was 12%, while the deferred rate and false-positive rate were 24% and 18%, respectively. There was no misdiagnosis between the benign and malignant categories. The histologic subtypes were correctly predicted in 78% of cases. There were limitations of scrape cytology in the diagnosis of LMP and mucinous tumors, which require histologic architectural evaluation and adequate histologic sampling. Scrape cytology is a simple, rapid, and inexpensive adjunctive technique that should be used in intraoperative consultation for ovarian lesions.

Intraoperative cytology increases the diagnostic accuracy of frozen sections for the confirmation of various tissues in the parathyroid region

The identification of parathyroid gland tissue and its distinction from adjacent structures such as thyroid gland, lymphoid, fibroadipose, and, rarely, thymic tissues on frozen section (FS) may be challenging owing to freezing artifact. Intraoperative cytology (IC) provides valuable complementary morphologic details. We evaluated 72 specimens with IC alone (group 1), followed by interpretation with FS to reach a final interpretation using IC and FS together (group 2). An additional 105 specimens were evaluated by FS alone (group 3). Permanent section diagnosis was used as the "gold standard." Sensitivity and specificity were 100% for group 2, compared with lower values for group 1 (98% and 100%, respectively) and group 3 (94% and 94%, respectively). IC is a valuable adjunct to FS during intraoperative consultation for evaluation of tissue in a parathyroid location.

Evaluation of micrometastases in sentinel lymph nodes of cutaneous melanoma: higher diagnostic accuracy with Melan-A and MART-1 compared with S-100 protein and HMB-45

Accurate diagnosis of micrometastases in sentinel lymph nodes of cutaneous melanoma is critical for proper clinical management. S-100 protein and HMB-45 are the traditional immunomarkers widely used for this purpose. However, the interpretation of micrometastases by these markers is difficult with significant reduction in the diagnostic accuracy. S-100 protein demonstrates immunoreactivity for other nonmelanoma cells and obscures nuclear details, which are crucial for the interpretation of single cell metastases. We compared the new melanoma markers, Melan-A (clone A103) and MART-1 (clone M2-7C10), with S-100 protein and HMB-45, by examining 77 formalin-fixed paraffin-embedded sections of sentinel lymph nodes from 13 cases of primary cutaneous melanoma. CD68 (PG-M1) and hematoxylin-eosin-stained sections were also studied. Four pathologists interpreted the staining pattern after concealing the identity of each immunomarker. Az values (area under receiver operating characteristic curve) with receiver operating characteristic curve were higher with Melan-A (0.9742) and MART-1 (0.9779) compared with S-100 protein (0.8034) and HMB-45 (0.8651), demonstrating a higher diagnostic accuracy with Melan-A and MART-1 with superior detection of melanoma micrometastases. Melan-A and MART-1 showed sharp cytoplasmic immunoreactivity, almost exclusively restricted to the melanoma cells. Therefore, Melan-A and MART-1 are recommended for the evaluation of micrometastases in sentinel lymph nodes of cutaneous melanoma as a routine alternative to S-100 protein and HMB-45.