Clinical outcomes for "suspicious" category in thyroid fine-needle aspiration biopsy: patient's sex and nodule size are possible predictors of malignancy.
Abstract: Context.--Fine-needle aspiration (FNA) is recommended as an initial screening tool for the diagnosis of thyroid nodules. Approximately 10% of thyroid FNA diagnoses are "suspicious for neoplasm," warranting surgical resection.

Objectives.--To examine the role of a patient's age, sex, size of nodule, and morphologic features as possible predictors of malignancy in patients with cytologic diagnosis of "suspicious for neoplasm."

Design.--Cytopathology slides and reports of 402 consecutive thyroid FNAs from 2000-2005 interpreted as "suspicious" were reviewed. Of these, 180 cases that had subsequent surgical resection were selected.

Results.--Of the 108 cases suspicious for follicular neoplasm on cytologic evaluation, histologic follow-up showed malignancy in 26 (24%). Of the 37 cases suspicious for Hurthle cell neoplasm, 15 (41%) had malignancy. Of the 35 cases suspicious for malignancy, 29 had malignant his tologic diagnoses. Among cases with cytologic diagnoses of "suspicious for follicular or Hurthle cell neoplasm," the rate of malignancy in female patients was 22% as compared to 43% in male patients (P = .02). The rate of malignancy in nodules less than 2 cm was 19% compared to 47% in nodules measuring 2 cm or larger (P < .001). These differences were statistically significant. No statistically significant difference was noted between the age of the patient and the rate of benign versus malignant diagnosis.

Conclusions.--Malignant tumors were more frequent in male patients with a cytologic diagnosis of "suspicious for follicular or Hurthle cell neoplasm" than in female patients. Risk of malignancy was higher in nodules measuring 2 cm or larger. Age of the patient was not a predictor of malignancy.
Article Type: Clinical report
Subject: Thyroid diseases (Diagnosis)
Thyroid diseases (Care and treatment)
Biopsy, Needle (Usage)
Morphology (Analysis)
Thyroidectomy (Usage)
Authors: Raparia, Kirtee
Min, Soo Kee
Mody, Dina R.
Anton, Rose
Amrikachi, Mojgan
Pub Date: 05/01/2009
Publication: Name: Archives of Pathology & Laboratory Medicine Publisher: College of American Pathologists Audience: Academic; Professional Format: Magazine/Journal Subject: Health Copyright: COPYRIGHT 2009 College of American Pathologists ISSN: 1543-2165
Issue: Date: May, 2009 Source Volume: 133 Source Issue: 5
Accession Number: 230152001
Full Text: Palpable thyroid nodules are relatively common, being reported in 4% to 7% of the adult population. Most of these lesions are benign, with a malignancy rate of less than 5%. (1) Therefore, surgery with its attendant costs, risks, and complications is an unnecessary procedure for many patients.

Fine-needle aspiration (FNA) is widely accepted as the most accurate and cost-effective tool for the initial screening and triage of thyroid nodules. (2-4) According to the "National Cancer Institute (NCI) Thyroid Fine Needle Aspiration State of the Science Consensus Conference," every patient with a palpable thyroid nodule is a candidate for FNA procedure. (5) The introduction of fine-needle aspiration has decreased the percentage of patients undergoing thyroidectomy by 25% and has increased the yield of surgery (ie, finding malignancy in thyroidectomy specimens) from 15% to at least 30%. (1,6)

In the recent NCI Consensus Conference, a 7-tier diagnostic scheme was proposed consisting of the following categories: benign, atypia of undetermined significance, suspicious for follicular, suspicious for Hurthle cell neoplasm, suspicious for malignancy, malignant, and insufficient for diagnosis. The aspirates that are "suspicious for follicular or Hurthle cell neoplasm" are cellular smears consisting of follicular/Hurthle cells in a scant colloid background. Because the criteria for malignancy in both follicular neoplasm (FN) and Hurthle cell neoplasm (HN) requires vascular or capsular invasion, "suspicious" diagnosis on FNA usually warrants surgical resection. In reported series, the rate of malignancy in thyroidectomy specimens of patients with initial cytologic diagnoses of "suspicious for FN" varies from 15% to 47% and from 20% to 45% for "suspicious for HN." Some studies suggest that a Hurthle cell versus follicular cell morphology, patient's age or sex, and/or size of nodule can be predictors of a malignant outcome. (7-15) In contrast, other reports state that clinical factors are not helpful in predicting carcinoma in patients with suspicious FNA findings. (12) These results are contradictory and confusing. In this study, we report our experience with thyroid FNA diagnoses of "suspicious" in a series of patients who underwent subsequent thyroidectomy. Age, sex, and size of the nodule were examined as possible predictors of malignancy. We specifically focused on the FNA diagnosis of "suspicious for FN" and "suspicious for HN" to compare the rate of malignancy in these 2 groups.

MATERIALS AND METHODS

Cytopathology reports of all thyroid FNAs performed at The Methodist Hospital in Houston, Texas, from 2000-2005 were reviewed. The total number of thyroid FNAs during this period was 3997. Thyroid FNA diagnoses were grouped into 4 major categories: benign, malignant, suspicious, and nondiagnostic. The "suspicious" category was subclassified to "suspicious for follicular neoplasms," "suspicious for Hurthle cell neoplasms," or "suspicious for malignancy." Cellular adenomatous nodules that were worrisome for adenoma or carcinoma were reported under the "suspicious" category and comprised less than 5% of cases in this category. The cases with mild cytologic atypia and abundant colloid were reported as "negative."

Cytopathology slides and reports of all thyroid FNAs interpreted as "suspicious" were reviewed. Four hundred and two cases were suspicious for neoplasm. Surgical follow-up information was available for 180 of these 402 patients.

All FNA biopsies were performed at the Methodist Hospital, Houston. The aspirations were done with or without ultrasound guidance. Thyroid nodules that were easily palpable were aspirated by a board-certified cytopathologist and nonpalpable thyroid nodules were aspirated under ultrasound guidance by a radiologist. Less than 10% of FNA biopsies were performed by endocrinologists. All aspirations were performed with 23- to 25-gauge needles attached to a 10- or 20-mL syringe with or without a syringe holder. Each nodule was aspirated 3 to 5 times. Air-dried smears were immediately stained with the Diff-Quik methodology (Siemens Healthcare Diagnostics, Deerfield, Illinois) for adequacy check, and alcohol-fixed aspirates were stained according to the Papanicolaou methodology. The needles were rinsed in Roswell Park Memorial Institute (RPMI) media or CytoLyt (Cytyc Corporation, a Hologic Company, Boxborough, Massachusetts). These were used for making liquid-based preparations (ThinPrep) (Cytyc). An adequate FNA specimen was defined as containing 8 to 10 clusters of at least 6 to 8 well-preserved and well-visualized follicular cells. (16)

Histologic diagnoses were available in 180 cases. In most cases, lobectomy and isthmectomy were performed with intraoperative frozen-section evaluation.

The reports of all patients who underwent thyroid FNA biopsy and thyroidectomy with histologic evaluation were reviewed in accordance with institutional review board guidelines. The FNA biopsy results were analyzed for a possible association between malignancy rate and preoperative factors such as patient's age, patient's sex, size of nodule, and/or morphology (FN vs HN). Positive predictive values (PPV) were calculated for each group. Student t and Fisher exact tests were used for comparison and evaluation of variables. P values less than .05 were considered statistically significant.

Other morphologic features including increased single cells, nuclear pleomorphism, nuclear enlargement, macronucleoli, and quality of the colloid were also investigated as possible predictors of outcome.

RESULTS

The rate of the "suspicious" diagnosis for thyroid FNAs in our laboratory varied between 7% and 10% during the years these cases were collected. Of the 180 cases initially diagnosed as "suspicious for neoplasm" for which surgical follow-up information was available, cytologic evaluation found 108 cases were suspicious for FN, 37 for HN, 34 for papillary carcinoma, and 1 for medullary carcinoma. The FNA cytology results were correlated with the subsequent histologic diagnoses (Table 1).

Of the 108 cases diagnosed as "suspicious for FN" on cytologic evaluation, the follow-up histologic diagnoses were malignant in 26 (24%) and benign in 82 (76%) cases. There were 77 women and 31 men in this group. The patients in this group ranged in age from 18 to 80 years with a mean age of 48.9 years.

Of the 37 cases diagnosed as "suspicious for HN," 15 (41%) were diagnosed as malignant in the subsequent histologic material and 22 (59%) were benign. There were 31 women and 6 men in this group. The patients ranged in age from 27 to 77 years with a mean age of 51.5 years.

Of the 34 cases diagnosed as "suspicious for papillary carcinoma" on cytologic evaluation, the histologic follow up showed malignant tumors in 28 (82%) and benign lesions in 6 (18%) patients. There were 28 women and 6 men in this group, with ages ranging from 26 to 95 years and a mean age of 48.6 years.

The PPV for a malignant neoplasm was 24% (26/108) for patients with a cytologic diagnosis of "suspicious for FN" and 41% (15/37) for a diagnosis of "suspicious for HN." The difference was not statistically significant (P = .06). The PPV for a malignant neoplasm was 82% (28/34) for cases with cytologic diagnoses of "suspicious for papillary carcinoma."

The rate of finding adenomas or carcinomas was 69% (74/108) in cases with a cytologic diagnosis of "suspicious for FN." It was higher (92%, 34/37) in cases with a cytologic diagnosis of "suspicious for HN."

Among cases with a cytologic diagnosis of FN, the rate of malignancy for female patients was 18% (14/77) as compared to 39% (12/31) for male patients. This difference was statistically significant (P = .04). When the cytologic diagnosis of "suspicious for FN or HN" was combined, the rate of malignancy for men was 43% compared to 22% for women. This difference was statistically significant as well (P = .02) (Figure).

The rate of malignancy in nodules less than 2 cm was 19% compared to 47% in nodules measuring 2 cm or larger. This difference was statistically significant (P < .001) (Table 2).

The patients with cytologic diagnoses of "suspicious for FN or HN" were further subclassified on the basis of their age. There were 72 patients less than 50 years old. In this group of patients, the rates of malignancy (PPV) for cases with the diagnosis of "suspicious for FN" or "suspicious for HN" were 30% and 33%, respectively. There were 73 patients aged 50 years or older. The PPVs for diagnoses of FN and HN were 19% and 42%, respectively, in this group. The overall PPV for patients with cytologic diagnoses of "suspicious for FN or HN" was 31% in patients younger than 50 years and 25% in patients 50 years or older. The difference was not statistically significant.

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We also looked at several morphologic features including crowding, increased single cells, nuclear pleomorphism, nuclear enlargement, macronucleoli, and quality of the colloid. None of these factors correlated with surgical outcome.

COMMENT

Fine-needle aspiration biopsy of the thyroid gland is safe, inexpensive, minimally invasive, and highly accurate in the diagnosis of thyroid nodules (1,2,6) Practice guidelines proposed by the American Thyroid Association and the National Comprehensive Cancer Network state that FNA should be used as the initial diagnostic test, before both thyroid scintigraphy and ultrasonography. (4) If FNA is performed by a skilled physician and is evaluated by an experienced pathologist, false-positive or false-negative results are uncommon.

Until recently, there was no standard classification for reporting thyroid FNA findings. Thyroid FNA diagnoses were usually grouped into 4 categories: benign, malignant, suspicious, and nondiagnostic. In some cytology reports, vague and ambiguous terminology, such as "inconclusive" or "indeterminate," was used. This terminology was confusing and interpreted differently by various treating physicians. At our institution, the "suspicious" category was usually followed by a descriptive diagnosis of "suspicious for follicular neoplasms," "suspicious for Hurthle cell neoplasms," or "suspicious for papillary carcinoma." This is essentially in line with the recent 6-tier diagnostic scheme, which was proposed at the recent NCI Thyroid Fine Needle Aspiration State of the Science Consensus Conference. Most committee members and participants at this conference favored the following 7-category diagnostic scheme: benign, atypia of undetermined significance, suspicious for follicular neoplasm, suspicious for Hurthle cell neoplasm, suspicious for malignancy, malignant, and insufficient for diagnosis.5 This scheme is beneficial for triaging patients for either clinical follow-up or surgical management. (17)

Patients with benign results from thyroid cytologic evaluation are usually followed-up with medical management, and malignant nodules are treated surgically.18 The nondiagnostic/unsatisfactory and atypical categories warrant repeated FNAs.

In our series, the patients with cytologic diagnoses of "suspicious for papillary carcinoma" had a high likelihood of having papillary carcinoma (82%) on subsequent histologic evaluation. This finding is consistent with other recent reports that cited a PPV ranging from 72% to 90%.6-9 The high prevalence of malignancy in this group of patients justifies surgical treatment. In most centers in the United States, these patients undergo lobectomy with intraoperative evaluation. If papillary carcinoma is confirmed, the surgeon proceeds with a concurrent completion thyroidectomy. More challenging and controversial is the management of patients with follicular or Hurthle cell neoplasms. Thyroid lobectomy with frozen-section analysis is a common approach in this group of patients as well. However, frozen-section evaluation may miss vascular or capsular invasion because of the limited number of sections and frozen-section artifacts. In these cases, final diagnosis is deferred to examination of the entire capsule on permanent sections, and a second operation may be required if the initial procedure was unilateral thyroid lobectomy.

Some investigators have tried to find out which preoperative patient or tumor characteristics can predict a malignant outcome for follicular or Hurthle cell neoplasms. The results are controversial and contradictory. Some studies have suggested that the findings more closely associated with a malignant nodule were patient's age, size of the tumor, or sex of the patient. Other studies have concluded that in patients with suspicious FNA biopsy findings, these clinical factors or morphologic features were not helpful in predicting carcinoma and thus cannot be used to reliably select patients for more extensive thyroidectomy. (10-15)

Tyler et al reported that patients who were 50 years or older and had a cytologic diagnosis of "suspicious for FN or HN" on FNA were more likely to harbor an invasive carcinoma.9 On the basis of their data, for patients 50 years or older, if the frozen section showed follicular neoplasm on unilateral lobectomy, they suggested performing a completion thyroidectomy during the initial surgery. In this age group, for total thyroidectomy, they did not require a confirmation of malignancy on frozen-section evaluation. On the other hand, according to their algorithm, for patients younger than 50 years who had frozen-section confirmation of the FN or HN with no evidence of vascular or capsular invasion, no further surgery was required. In our series of 145 cases with cytology diagnoses of "suspicious for FN or HN," there was no association between risk of malignancy and the patient's age. Indeed, rate of malignancy (PPV) in 72 patients younger than 50 years was 31% (22/73), which was slightly higher than the PPV value of 25% in the 73 patients 50 years and older. Another, more recent study by the same group, performed on a larger sample size, did not confirm the previous finding of increased risk of malignancy in patients 50 years or older.8 In their more recent study, this group reported PPVs of 15% for cytologic diagnoses of follicular neoplasms, 20% for Hurthle cell neoplasms, and 82% for papillary carcinomas. They indicated that a nodule diameter greater than 2 cm was the only factor associated with an increased risk of malignancy (P < .03). This finding is in accordance with our PPV finding for malignancy of 19% for nodules less than 2 cm as compared to 47% for nodules measuring 2 cm or larger.

Pu et al (15) observed that FNA diagnoses for men and older patients with Hurthle cell neoplasm carry a higher risk of carcinoma upon subsequent thyroidectomy. In our study, we found statistically significant difference between the rate of malignancy in men with a prior cytologic diagnosis of "suspicious for neoplasm" as compared to women with similar diagnosis. Among cases with a cytologic diagnosis of "suspicious for FN," the rate of malignancy in female patients was 18% as compared to 39% in male patients. The overall rate of malignancy in men with cytologic diagnosis of "suspicious for FN or HN" was 43% compared to 22% in women with similar diagnosis.

Some authors have reported a higher rate of malignancy for the FNA diagnosis of "suspicious for HN" compared to the diagnosis of "suspicious for FN"14 (Table 3). In our series, the risks of having a malignant neoplasm for patients with cytologic diagnoses of "suspicious for HN" was 41%, which was higher than the 26% risk of malignancy for patients with diagnoses of "suspicious for FN." This difference, however, was not statistically significant (P = .06).

Our data show that malignant tumors were more frequent in men with a cytologic diagnosis of "suspicious for follicular or Hurthle cell neoplasm" than for women with similar cytologic diagnoses. There was also a statistically significant difference between the size of the nodule (>2 cm) and rate of benign versus malignant diagnoses. The positive predictive value for malignancy in cases diagnosed as "suspicious for Hurthle cell neoplasm" was higher than in cases diagnosed as "suspicious for follicular neoplasm." The difference, however, was not statistically significant. None of the morphologic factors, such as increased single cells, nuclear pleomorphism, nuclear enlargement, macronucleoli, or quality of the colloid, correlated with surgical outcome.

References

(1.) Thyroid test for the clinical biochemist and physician--H: thyroid fine needle aspiration (FNA) and cytology. Thyroid. 2003;13:80-86.

(2.) Gharib H, GoellnerJR. Fine-needle aspiration biopsy of the thyroid: an appraisal. Ann Intern Med. 1993;1 18:282-289.

(3.) Hadi M, Gharib H, Goellner JR, Heerden JA. Has fine-needle aspiration biopsy changed thyroid practice? Endocr Pract. 1997;3:9-13.

(4.) The American Thyroid Association Guidelines Task Force: management guidelines for patients with thyroid nodules and differentiated thyroid cancer. Thyroid. 2006;16:1-33.

(5.) National Cancer Institute. Third draft of the review and conclusions document. NCI Thyroid Fine Needle Aspiration (FNA) State of the Science Conference and Web site. http://thyroidfna.cancer.gov. Accessed June 4, 2008.

(6.) Amrikachi M, Ramzy I, Rubenfeld S, Wheeler TM. Accuracy of fine-needle aspiration of thyroid. Arch Pathol Lab Med. 2001;12 5:484-488.

(7.) Deveci MS, Deveci G, Livolsi VA, Gupta PK, Baloch ZW. Fine-needle aspiration of follicular lesions of the thyroid: diagnosis and follow-up. Diagn Cy topathol. 2007;35(9):579-583.

(8.) Sclabas GM, Staerkel GA, Shapiro SE, et al. Fine-needle aspiration of the thyroid and correlation with histopathology in a contemporary series of 240 patients [discussion in: Am J Surg. 2003;186:709-710]. Am J Surg. 2003;186:702-709.

(9.) Tyler DS, Winchester DJ, Caraway NP, Hickey RC, Evans DB. Indeterminate fine-needle aspiration biopsy of the thyroid: identification of subgroups at high risk for invasive carcinoma. Surgery. 1994;116:1054-1060.

(10.) Schlinkert RT, van Heerden JA, GoellnerJR, et al. Factors that predict malignant thyroid lesions when fine-needle aspiration is "suspicious for follicular neoplasm". Mayo Clin Proc. 1997;72:913-916.

(11.) McHenry CR, Thomas SR, Slusarczyk SJ, Khiyami A. Follicular or Hurthle cell neoplasm of the thyroid: can clinical factors be used to predict carcinoma and determine extent of thyroidectomy? [discussion in: Surgery. 1999;126:802804] Surgery. 1999;126:798-802.

(12.) Kim ES, Nam-Goong IS, Gong G, Hong SJ, Kim WB, Shong YK. Postoperative findings and risk for malignancy in thyroid nodules with cytological diagnosis of the so-called "follicular neoplasm". Korean J Intern Med. 2003;18:94-97.

(13.) Baloch ZW, Fleisher S, LiVolsi VA, Gupta PK. Diagnosis of "follicular neoplasm": a gray zone in thyroid fine-needle aspiration cytology. Diagn Cytopathol. 2002;26:41-44.

(14.) Giorgadze T, Rossi ED, Fadda G, Gupta PK, Livolsi VA, Baloch Z. Does the fine-needle aspiration diagnosis of "Hurthle-cell neoplasm/follicular neoplasm with oncocytic features" denote increased risk of malignancy? Diagn Cytopathol. 2004;31:307-312.

(15.) Pu RT, Yang J, Wasserman PG, Bhuiya T, Griffith KA, Michael CW. Does Hurthle cell lesion/neoplasm predict malignancy more than follicular lesion/neoplasm on thyroid fine-needle aspiration? Diagn Cytopathol. 2006;34:330-334.

(16.) Kini S. Guides to Clinical Aspirarion Biopsy of the Thyroid. New York, New York: Igaku-Shoin; 1987.

(17.) Yang J, Schnadig V, Logrono R, Wasserman PG. Fine-needle aspiration of thyroid nodules: a study of 4703 patients with histologic and clinical correlations. Cancer. 2007;1 1 1(5):306-315.

(18.) AACE/AME Task Force on Thyroid Nodules. Thyroid nodule guidelines. Endocr Pract. 2006;12(1):63-101.

Kirtee Raparia, Soo Kee Min, Dina R. Mody, Rose Anton, Mojgan Amrikachi,

Accepted for publication October 31, 2008.

From the Department of Pathology, The Methodist Hospital, Houston, Texas (Drs Raparia, Mody, Anton, and Amrikachi); and Hallym University Sacred Heart Hospital, Anyang, Gyeonggi, South Korea (Dr Min).

The authors have no relevant financial interest in the products or companies described in this article.

Reprints: Mojgan Amrikachi, MD, Department of Pathology, The Methodist Hospital, Weill Medical College of Cornell University, 6565 Fannin Street, Houston, TX 77030 (e-mail: mamrikachi@tmhs.org).
Table 1. Cytology-Histology Correlates for the "Suspicious"
Cytology Category in Thyroid Fine-Needle Aspiration
(n = 180)

                                    Cytologic Diagnosis
                           Suspicious for FN    Suspicious for HN
                               (n = 108)            (n = 37)
Histologic Diagnosis        Cases, No. (%)       Cases, No. (%)

  Benign lesions                82 (76)              22 (59)
  Hyperplastic nodules          34 (31)               3 (8)
  Follicular adenoma            42 (39)               3 (8)
  Hurthle cell adenoma           6 (6)               16 (43)
Malignant lesions               26 (24)              15 (41)
  Follicular carcinoma          15 (14)               2 (5)
  Hurthle cell carcinoma         2 (2)               8 (22)
  Papillary carcinoma            9 (8)               4 (10)
  Other carcinoma                  0                  1 (3)

                                  Cytologic Diagnosis
                           Suspicious for PC   Suspicious for MC
                               (n = 34)            (n = 1)
Histologic Diagnosis        Cases, No. (%)     Cases, No. (%)

Benign lesions                  6 (18)                 0
  Hyperplastic nodules          5 (15)                 0
  Follicular adenoma             1 (3)                 0
  Hurthle cell adenoma             0                   0
Malignant lesions               28 (82)                0
  Follicular carcinoma           1 (3)                 0
  Hurthle cell carcinoma         1 (3)                 0
  Papillary carcinoma           26 (76)                0
  Other carcinoma                  0                1 (100)

Abbreviations: FN, follicular neoplasm; HN, Hurthle cell neoplasm; MC,
medullary carcinoma; PC, papillary carcinoma.

Table 2. Correlation Between Benign and Malignant
Diagnoses and Nodule Size in Cytologic Diagnosis of
Follicular or Hurthle Cell Neoplasm (n = 145) (a)

Nodule                             Surgical Diagnosis
Size               Benign, No. (%)   Malignant, No. (%)   Total, No.

<2 cm                  73 (81)            17 (19)             90
[greater than or       29 (53)            26 (47)             55
equal to] 2 cm

(a) Fisher exact [chi square] test between the size of nodules less
than 2 cm versus nodules 2 cm or larger and benign versus malignant
process; P < .001.

Table 3. Data From Other Studies: Positive Predictive Value (PPV) of
Cytologic Diagnosis of "Suspicious for" Follicular Neoplasm (FN) Versus
Hurthle Cell Neoplasm (HN)

                                     Suspicious for FN
                             No. of   Malignant
Source, y                     Cases     Cases     PPV, % (a)

Tyler et al, (9) 1994          43           8        19
McHenry et al, (11) 1999       66          14        21
Baloch et al, (13) 2002       122          37        31
Kim et al, (12) 2003          215         102        47
Sclabas et al,(8) 2003         73          11        15
Giorgadze et al, (14) 2004     NA          NA        NA
Pu et al, (150 2006           216          60        28
Present study                 108          26        24
Total                         843         258        30

                                    Suspicious for HN
                             No. of   Malignant
Source, y                    Cases      Cases     PPV, % (a)

Tyler et al, (9) 1994          18         5          28
McHenry et al, (11) 1999        9         3          33
Baloch et al, (13) 2002        NA        NA          NA
Kim et al, (12) 2003           42        15          36
Sclabas et al,(8) 2003         10         2          20
Giorgadze et al, (14) 2004    169        76          45
Pu et al, (15) 2006            87        27          31
Present study                  37        15          41
Total                         372       143          38

Abbreviation: NA, not available

(a) Proportion of patients with positive malignant outcomes on
histologic analysis.
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