Limited Tissue Biopsies and Hematolymphoid Neoplasms

Uses and limitations of small-volume biopsies for the diagnosis of lymphoma

Although surgical biopsy remains the gold standard for the diagnosis of lymphoma, small-volume biopsies including fine-needle aspiration and core needle biopsy are increasingly being used as a first line diagnostic tool. Small-volume biopsies are safe, rapid and cost effective; however, diagnostic utility varies by lymphoma subtype. It is important for pathologists and clinicians to recognize both the strengths and limitations of such biopsies.

CT-guided percutaneous transthoracic needle biopsy for anterior mediastinal lymphoma: the role of PET/CT

BACKGROUND

Computed tomography (CT)-guided percutaneous transthoracic needle biopsy (PTNB) is not recommended as the diagnostic modality of choice for anterior mediastinal lymphoma, despite its advantages of minimal invasiveness and easy accessibility.

PURPOSE

To identify the modifiable risk factors for non-diagnostic results from CT-guided PTNB for anterior mediastinal lymphoma.

MATERIAL AND METHODS

This retrospective study identified CT-guided PTNB for anterior mediastinal lesions diagnosed as lymphoma between May 2007 and December 2021. The diagnostic sensitivity and complications were investigated. The appropriateness of PTNB targeting was evaluated using positron emission tomography (PET)/CT and images from intra-procedural CT-guided PTNB. Targeting was considered inappropriate when the supposed trajectory of the cutting needle was within a region of abnormally low metabolism. The risk factors for non-diagnostic results were determined using logistic regression analysis.

RESULTS

A total of 67 PTNBs in 60 patients were included. The diagnostic sensitivity for lymphoma was 76.1% (51/67), with an immediate complication rate of 4.5% (3/67). According to the PET/CT images, PTNB targeting was inappropriate in 10/14 (71.4%) of the non-diagnostic PTNBs but appropriate in all diagnostic PTNBs (P <0.001). Inappropriate targeting was the only significant risk factor for non-diagnostic results (odds ratio = 203.69; 95% confidence interval = 8.17-999.99; P = 0.001). The number of specimen acquisitions was not associated with non-diagnostic results (P = 0.40).

CONCLUSIONS

Only inappropriate targeting of the non-viable portion according to PET/CT was an independent risk factor for non-diagnostic results. Acquiring PET/CT scans before biopsy and targeting the viable portion on PET/CT may help improve the diagnostic sensitivity of PTNB.

Immunocytochemistry on frozen-embedded cell block for the diagnosis of hematolymphoid cytology specimen: a straightforward alternative to the conventional cell block

Agarose-based cell block (CB) technique can be modified to be combined with the frozen section technique for the preparation of a high-quality frozen-embedded CB (F-CB) from an effusion or fine-needle aspiration (FNA) cytology sample. This combined technique can be effectively used for the immunocharacterization of the hematolymphoid cells on F-CB. To demonstrate the applicability of performing diagnostic ICC on F-CB, we have analyzed the immunophenotype of the hematolymphoid cells in a series of eight cases of effusions and eight cases of FNA cytology specimens by using CB-ICC on sections cut from frozen-embedded CBs. The SurePathTM residue or cytologic material scraped off from the FNA cytology smear that was diagnostic for or suspicious of hematolymphoid malignancy was pelleted and pre-embedded in agarose. Half of the agarose-embedded pellet was frozen-embedded in OCT compound for the preparation of F-CB, while the other half was processed for the preparation of paraffin-embedded CB. Sections cut from the F-CB and P-CB were used for CB-ICC. Panels of ICC on the F-CBs could enable the immunocytochemical differential diagnosis of large cell hematologic malignancies that encompass anaplastic large cell lymphoma and other forms of large-cell hematolymphoid malignancies such as large B-cell lymphomas, anaplastic plasma cell myeloma, myeloid sarcoma, and T-lymphoblastic lymphoma. It also appeared that the small B-cell lymphomas in the effusions or FNAs could be differentially diagnosed with the aid of CB-ICC on the F-CB. A modified agarose-based CB technique can be combined with the frozen-embedded CB method for the preparation of F-CB that can be directly used for the immunocytochemical differential diagnosis of hematolymphoid cytology samples.

Small volume biopsy diagnostic yield at initial diagnosis versus recurrence/transformation of follicular lymphoma: A retrospective Cyto-Heme Interinstitutional Collaborative study

BACKGROUND

Few studies have evaluated diagnostic yield of small volume biopsies (SVB) for the diagnosis and management of follicular lymphoma (FL).

METHODS

The authors performed a multi-institutional retrospective analysis of SVBs including fine-needle aspiration (FNA) and needle core biopsy (NCB) for initial FL diagnosis and suspected recurrence or transformation of FL. A total of 676 workups beginning with SVB were assessed for the mean number of biopsies per workup, the proportion of workups requiring multiple biopsies, and the proportion with a complete diagnosis including grade, on initial biopsy.

RESULTS

Compared to workups performed for question transformation/recurrence, those done for initial FL diagnosis were significantly more likely to require multiple biopsies (p < .01), had a higher mean number of biopsies per workup (1.7 vs. 1.1, absolute standardized difference = 1.1), and a lower complete diagnosis rate at initial biopsy (39% vs. 56%). At initial FL diagnosis, NCB +/- FNA was associated with fewer biopsies per workup compared to FNA +/- CB (1.2 vs. 1.9), fewer workups requiring multiple biopsies (23% vs. 83%), and a higher complete diagnosis rate (71% vs. 18%). In contrast, during assessment for transformation/recurrence, NCB and FNA showed a similar mean number of biopsies per workup (1.2 vs. 1.2) and few workups required multiple biopsies (6% vs. 19%).

CONCLUSIONS

SVB at initial FL diagnosis often required additional biopsies to establish a complete diagnosis. In contrast, when assessing for transformed/recurrent FL, additional biopsies were generally not obtained regardless of SVB type, suggesting that in these clinical settings SVB may be sufficient for clinical decision-making.

Utility and Limitations of Fine-Needle Aspiration Cytology in the Diagnosis of Lymphadenopathy

BACKGROUND

Fine needle aspiration cytology (FNAC) is a valuable tool for evaluating lymphadenopathy. The purpose of this study was to assess the reliability and effectiveness of FNAC in the diagnosis of lymphadenopathy.

METHODS

Cytological characteristics were evaluated in 432 patients who underwent lymph node FNAC and follow-up biopsy at the Korea Cancer Center Hospital from January 2015 to December 2019.

RESULTS

Fifteen (3.5%) of the four hundred and thirty-two patients were diagnosed as inadequate by FNAC, with five (33.3%) of these diagnosed as metastatic carcinoma on histological examination. Of the 432 patients, 155 (35.9%) were diagnosed as benign by FNAC, with seven (4.5%) of these diagnosed histologically as metastatic carcinoma. A review of the FNAC slides, however, showed no evidence of cancer cells, suggesting that the negative results may have been due to FNAC sampling errors. An additional five samples regarded as benign on FNAC were diagnosed as non-Hodgkin lymphoma (NHL) by histological examination. Of the 432 patients, 223 (51.6%) were cytologically diagnosed as malignant, with 20 (9.0%) of these diagnosed as tissue insufficient for diagnosis (TIFD) or benign on histological examination. A review of the FNAC slides of these 20 patients, however, showed that 17 (85.0%) were positive for malignant cells. The sensitivity, specificity, positive predictive value (PPV), negative predictive values (NPV), and accuracy of FNAC were 97.8%, 97.5%, 98.7%, 96.0%, and 97.7%, respectively.

CONCLUSIONS

Preoperative FNAC was safe, practical, and effective in the early diagnosis of lymphadenopathy. This method, however, had limitations in some diagnoses, suggesting that additional attempts may be required according to the clinical situation.

Core Needle Biopsy in Lymphoma Diagnosis: The Diagnostic Performance and the Role of the Multidisciplinary Approach in the Optimization of Results

To compare the diagnostic accuracy of core needle biopsies (CNBs) and surgical excisional biopsies (SEBs), samples of lymphoid proliferation from a single institution from 2013 to 2017 (N=476) were divided into groups of CNB (N=218) and SEB (N=258). The diagnostic accuracy of these samples was evaluated as a percentage of conclusive diagnosis, according to the World Health Organization Classification of Tumours of Haematopoietic and Lymphoid Tissues . The contribution of clinical data, the assessment of sample adequacy by a pathologist during the procedure, the number and size of fragments, the needle gauge, the ancillary tests, and the type of lymphoid proliferation were also examined. The diagnostic accuracy of SEB was 97.3% and CNB 91.3% ( P =0.010). Additional factors considered essential for establishing the final diagnosis in some cases were: clinical information (20.6% CNB, 7.4% SEB; P <0.001); immunohistochemistry (96.3% CNB, 91.5% SEB; P =0.024); flow cytometry (12% CNB, 6.8% SEB; P =0.165); and other complementary tests (8.2% CNB, 17.3% SEB; P =0.058). Factors that did not influence performance were the evaluation of sample adequacy during the procedure, the number and size of fragments, and the needle gauge. Increased percentage of nondiagnostic CNB was observed in T-cell lymphomas (30%), followed by classic Hodgkin lymphoma (10.6%). The main limitation of CNB was the evaluation of morphologically heterogenous diseases. CNB is useful and safe in lymphoma diagnosis provided it is carried out by a team of experienced professionals. Having an interventional radiology team engaged with pathology is an essential component to achieve adequate rates of specific diagnoses in CNB specimens.

Lymph node excisions provide more precise lymphoma diagnoses than core biopsies: a French Lymphopath network survey

According to expert guidelines, lymph node surgical excision is the standard of care for lymphoma diagnosis. However, core needle biopsy (CNB) has become widely accepted as part of the lymphoma diagnostic workup over the past decades. The aim of this study was to present the largest multicenter inventory of lymph nodes sampled either by CNB or surgical excision in patients with suspected lymphoma and to compare their diagnostic performance in routine pathologic practice. We reviewed 32 285 cases registered in the French Lymphopath network, which provides a systematic expert review of all lymphoma diagnoses in France, and evaluated the percentage of CNB and surgical excision cases accurately diagnosed according to the World Health Organization classification. Although CNB provided a definitive diagnosis in 92.3% and seemed to be a reliable method of investigation for most patients with suspected lymphoma, it remained less conclusive than surgical excision, which provided a definitive diagnosis in 98.1%. Discordance rates between referral and expert diagnoses were higher on CNB (23.1%) than on surgical excision (21.2%; P = .004), and referral pathologists provided more cases with unclassified lymphoma or equivocal lesion through CNB. In such cases, expert review improved the diagnostic workup by classifying ∼90% of cases, with higher efficacy on surgical excision (93.3%) than CNB (81.4%; P < 10-6). Moreover, diagnostic concordance for reactive lesions was higher on surgical excision than CNB (P = .009). Overall, although CNB accurately diagnoses lymphoma in most instances, it increases the risk of erroneous or nondefinitive conclusions. This large-scale survey also emphasizes the need for systematic expert review in cases of lymphoma suspicion, especially in those sampled by using CNB.

Global Cytopathology-Hematopathology Practice Trends

OBJECTIVES

Small-volume biopsy-fine-needle aspiration biopsy (FNAB) with or without core biopsy-is in increasing use in diagnosis and management of lymphoma patients. Our objective was to survey the current practice in small-volume biopsy diagnosis of lymphoma, focusing on the interaction among hematopathologists and cytopathologists and the integration of FNAB, core biopsy, and flow cytometry studies at sign-out.

METHODS

This study used a cross-sectional survey design employing the RedCap database distributed via nine pathology professional society email listservs. The survey consisted of 25 multiple-choice questions and several free text fields. In total, 128 pathologists participated.

RESULTS

Most respondents indicated that FNAB specimens in which lymphoma is a diagnostic consideration (FNAB-L) are seen daily or weekly (68/116; 58.6%). However, most institutions have separate hematopathology and cytopathology services (72/116; 62.1%) with inconsistent communication. When communication occurred, respondents were frequently inclined to reconsider their original diagnoses. Barriers identified included lack of communication, inadequate access to diagnostic studies, no formal subspecialty training, and various opinions regarding FNAB in diagnosing lymphoma.

CONCLUSIONS

This survey showed that FNAB-L specimens are common, with a lack of uniformity in how complementary fine-needle aspiration and core biopsy specimens or flow immunophenotyping results are shared across hematopathology and cytopathology services.

Fine-Needle Aspiration Diagnosis of Lymphoma Based on Cytomorphology Alone: How Accurate is it? - A Cyto-Histopathology Correlative Study

Context:

Fine-needle aspiration cytology (FNAC) is a rapid and accurate first-line diagnostic modality in lymphadenopathy.

Aims:

To determine the utility of FNAC for the diagnosis of lymphoma and highlight the various pitfalls in morphological interpretation.

Settings and Design:

This was a retrospective study of 3 years duration in which cytology diagnosis was compared with the follow-up histopathology diagnosis wherever available.

Results:

A cytodiagnosis of lymphoma was made in a total of 868 cases (2.8%) out of nearly 33,000 FNAC performed during the study period; 556 (64.1%) cases were diagnosed as non-Hodgkin lymphoma (NHL), 198 (22.8%) as Hodgkin lymphoma (HL), and in 114 (13.1%) cases, a cytological diagnosis of lymphoma without further categorization was given. Histopathological reports were available in 348 cases, with an overall concordance rate of 93.1% (324), which was slightly higher in the HL cases (95.8%) as compared to NHL (91.7%). Twenty-four cases (6.9%) showed discordant cytological diagnosis with subsequent histopathology. The main reasons for the erroneous diagnosis were the over-interpretation of the germinal center cells as atypical lymphoid cells, over-interpretation of immunoblasts with prominent nucleoli as Hodgkin cells, and sheets of monomorphic lymphoid cells interpreted as low-grade lymphoma.

Conclusion:

Cytomorphology alone can make a correct basic diagnosis of lymphoma with a high degree of accuracy. The errors in interpretation can be further reduced by careful attention to the diagnostic pitfalls and common differential diagnoses.

Lymph node FNA cytology: Diagnostic performance and clinical implications of proposed diagnostic categories

BACKGROUND

Despite widespread clinical use, lymph node fine-needle aspiration cytology (LN-FNAC) lacks universal acceptance for definitively diagnosing lymphomas. This is likely due to reports of lower diagnostic performance, inconsistent terminology use in cytopathology diagnostic reports, and only limited data on the clinical implications of LN-FNAC diagnoses. Recently, a uniform LN-FNAC cytopathological diagnostic reporting system was proposed (the Sydney System). This study evaluated LN-FNAC diagnostic performance and risks of malignancy associated with the proposed diagnostic categories.

METHODS

LN-FNAC specimens obtained in 2018-2019, with and without concurrent core biopsy, to evaluate for suspected lymphoma were analyzed (n = 349). LN-FNAC diagnoses were compared with final diagnoses obtained via subsequent tissue biopsy and/or clinical assessment.

RESULTS

The mean patient age was 57.6 years, and 41% were female. LN-FNAC was the initial diagnostic test in 223 (63.9%), and it was used to evaluate for recurrence in 126 (36.1%). LN-FNAC diagnosed 202 hematological malignancies (57.9%), 23 nonhematological malignancies (6.6%), and 124 reactive processes (35.5%). Subsequent tissue biopsy was performed in 42 (12%). The risks of malignancy per diagnostic category were as follows: inadequate, 58.3%; benign, 6.4%; atypical, 69.2%; suspicious, 96.7%; and malignant, 99.3%. LN-FNAC demonstrated up to 96.3% sensitivity, 91.91% specificity, and 87.35% accuracy. Optimal specimen quality and the use of intradepartmental consultation reduced diagnostic error rates in FNA cases without concurrent core biopsy (P = .029 and P = .0002 respectively).

CONCLUSIONS

LN-FNAC is accurate and reliable for the diagnosis of lymphoma. Inadequate LN-FNAC samples should be resampled due to a significant associated risk of lymphoma. The diagnostic performance of LN-FNAC may be improved with good specimen quality and reviews by multiple pathologists. Understanding the risks of malignancy associated with LN-FNAC diagnostic categories will help to guide optimal patient management.

An approach to small lymph node biopsies: pearls and pitfalls of reporting in the real world

Recent advances in interventional radiology have resulted in the utilization of small lymph node biopsies, including fine-needle aspiration (FNA) and core needle biopsy (CNB) as an initial diagnostic tool in hematopathology. A major challenge to the utilization of FNA and CNB is the limited-to-scant tissue often available. We propose delegation of the task of handling biopsy specimens to the laboratory staff by the biopsy operators, in order to optimize the utilization of the specimen. Furthermore, in order to effectively diagnose hematolymphoid neoplasms a variety of ancillary tests including immunohistochemistry, flow cytometry, molecular analysis, florescence in situ hybridization (FISH) are necessary. We propose morphological evaluation coupled with careful utilization of ancillary studies along with clinical correlation to approach the correct diagnosis. Our morphological assessment considers the types of proliferating cell population: mainly small cells, sheets of large cells, or scattered large cells among small cells. This is followed by employment of the corresponding immunopanel to assess the differential diagnosis in each of the three categories. We also elaborate on the importance for pathologists to become proficient in understanding the limitations of small tissue biopsies as well as the differences in interpretation, and wording their reports to help clinicians and direct them to further investigate and/or to re-biopsy when necessary.

Role of FNA with core biopsy or cell block in patients with nodular lymphocyte-predominant Hodgkin lymphoma

BACKGROUND

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) represents a diagnostic challenge on surgical excisional or incisional biopsy. Classification is further challenging on fine needle aspiration (FNA) material accompanied by needle core and/or cell block biopsy (FNA+core/CB).

METHODS

The authors studied all FNA+core/CB and surgical excisional or incisional biopsies to evaluate for lymphoma in patients who had a prior history of NLPHL or subsequent diagnosis of NLPHL over a 5-year period from 2012 through 2016.

RESULTS

Patients who ultimately were diagnosed with NLPHL represented <0.5% of those who underwent FNA+core/CB for an initial suspicion of lymphoma. FNA+core/CB resulted in a definitive diagnosis in 7 of 13 cases, and surgical excisional or incisional biopsy specimens resulted in a definitive diagnosis in 13 of 13 cases (chi-square statistic, 9.6; P = .002). At initial diagnosis, FNA+core/CB was negative in 2 cases and atypical or suspicious in 3 cases; all 5 of those patients required surgical excisional or incisional biopsy for a definitive lymphoma diagnosis. By contrast, patients who underwent FNA+core/CB for recurrent lymphoma required surgical excisional or incisional biopsy in only 1 of 8 cases (chi-square statistic, 9.5; P = .002). Flow cytometry was positive for a light-chain-restricted B-cell population in only 1 of 11 biopsies that were involved by lymphoma.

CONCLUSIONS

Surgical excisional or incisional biopsy remains the gold standard for NLPHL diagnosis and for distinguishing progression to a T-cell/histiocyte-rich large B-cell lymphoma pattern. At a tertiary cancer center with routine collaborative diagnosis of lymphoma on FNA+core/CB by cytopathologists and hematopathologists, FNA+core/CB performs well to assess for recurrent or transformed NLPHL, rarely requiring subsequent surgical excisional or incisional biopsy. FNA+core/CB has limited sensitivity in the initial diagnosis setting.