Metastatic HPV-related head and neck squamous cell carcinoma to the lung and mediastinal lymph nodes in aspirated cytology material: A diagnostic pitfall

Application of the international system for reporting serous fluid cytopathology on pleural effusion cytology with paired pleural biopsy: A new insight and novel approach on risk of malignancy

INTRODUCTION

The risk of malignancy (ROM) remains an area of interest for further evaluation in reporting systems including in International System for reporting serous fluid cytopathology (TIS), which is a standardized system for reporting effusion cytology. Herein, we report our findings in further investigation of ROM in TIS by studying on paired pleural effusion specimens and corresponding pleural biopsies with emphasis on negative for malignancy, and atypia of undetermined significance categories.

MATERIALS AND METHODS

The  Johns Hopkins Hospital pathology database was retrospectively searched for patients with a pleural biopsy (PBX) and a paired pleural effusion (PF) cytology specimens over a 4-year period. We employed the TIS categories. The following statistical parameters were evaluated: sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and ROM.

RESULTS

A total of 223 patient cases were included. Effusions TIS reclassification and ROM were as follows: 1.8% non-diagnostic (ROM 75%), 75.8% negative for malignancy (ROM 23%), 4.9% atypical cells of undetermined significance (ROM 45%), 2.2% suspicious for malignancy (ROM 80%), and 15.2% malignant (ROM 100%). Overall accuracy, sensitivity, specificity, PPV and NPV were calculated and were 79.4%, 45%, 97.7%, 91.2% and 77%, respectively. Among, discordant cases diagnosed negative for malignancy on PF and positive for malignancy on PBX, there were significant number of lymphomas, mesotheliomas, and sarcomas. Lung cancer was the most common carcinoma; however, rare types of carcinomas were noted. Cells blocks and immunohistochemistry (IHC) studies were utilized to confirm either malignant conditions or rule out malignancy in both cell blocks and histology biopsies.

CONCLUSION

This study demonstrates the high specificity and ROM for 'malignant' and 'suspicious for malignancy' categories in the TIS reporting system and highlights the modest negative predictive value for the 'negative for malignancy' category. Although Tissue biopsies are usually considered as 'gold standard', any definitive diagnosis of malignancy of body fluid should be considered positive for malignancy in further clinical decision-making.

A case of metastatic HPV-related cervical small cell neuroendocrine carcinoma with varying cytomorphology found in cytological specimens of a solid organ transplant recipient

Small cell neuroendocrine carcinoma (NEC) of the cervix is a rare gynecological malignancy, constituting 2%-5% of all such cases. As high-risk Human Papilloma Virus (HR-HPV) infections contribute to 85% of these tumors, small cell NEC poses a significant risk for solid organ transplant recipients, increasing their risk of progressive disease. We present a case of an uterine cervix small cell NEC with metastasis to the bladder and pleural cavities in a 53-year-old woman with a past medical history of kidney transplantation, who presented with abnormal uterine bleeding. The initial liquid preparation (ThinPrep) cytology stained with Papanicolaou (Pap) showed an adenocarcinoma not otherwise specified. At the time of diagnosis, the patient had diffusely metastatic disease. A subsequent uterine cervix biopsy was consistent with a small cell NEC. Despite treatment with chemotherapy, the patient's condition deteriorated, evidenced by a worsening right-sided pleural effusion one-month postdiagnosis. A pleural effusion showed a tumor with glandular features, with immunohistochemistry suggestive of metastatic adenocarcinoma. HR HPV E6/E7 RNA in situ hybridization (ISH) was positive. Bladder washing showed cytopathologic findings consistent with bladder involvement by small cell carcinoma. The patient's lesions in both urine and pleural fluids showed distinct cytomorphology. Within a year of diagnosis, the patient was declared deceased. This case highlights the existence of carcinoma admixed with NEC tumor, such as an HPV associated adenocarcinoma admixed with a NEC and underscores the elevated risk of HPV-related genital lesions in renal transplant patients. In patients with a history of solid organ transplant or other immunosuppressive conditions, there is an increased necessity for enhanced surveillance and appropriate cancer screening.

p16 immunostaining in cytology specimens: its application, expression, interpretation, and challenges

INTRODUCTION

p16 immunostaining is considered as a surrogate marker for human papillomavirus (HPV)-related head and neck squamous cell carcinomas (HNSCC). Herein, the utility of p16 is evaluated in cytology specimens.

MATERIAL AND METHODS

The electronic data of a large academic institution was searched for cytology cases accompanied by p16 (2014-2018). Cases were categorized based on body sites. P16 staining was quantified (negative [0%], focal/patchy, or diffusely positive [>70%]). HPV testing was correlated where available.

RESULTS

A total of 372 cases were included (male:female, 239:133). The largest differences in application of p16 between men and women were in head/neck cases (209 versus 59) and the abdominal cases (1 versus 33), respectively. p16 diffuse staining is seen in most squamous cell carcinomas, small cell carcinomas, and gynecologic serous carcinomas. p16 expression was patchy or negative in most adenocarcinoma, neuroendocrine carcinoma, spindle cell neoplasms, and benign conditions. HPV testing was done on 217 cases including 138 cases with strong p16 (127 HPV+/11 HPV-), 20 cases with focal/patchy P16 staining (6 HPV+/14 HPV-) and 59 cases with negative p16 staining (3 HPV+/56 HPV-).

CONCLUSIONS

Diffuse p16 staining aids in the diagnosis of HPV-related carcinomas, particularly HPV-related HNSCC, across the body and according to sex. In contrast, focal/patchy p16 staining does not correlate with HPV status across various body sites. In conclusion, intensity of p16 matters and should be correlated with cytomorphology, clinical history, and ancillary studies (eg, p40 immunostaining) for an accurate diagnosis and preventing diagnostic pitfalls.

Image-guided lymph node fine-needle aspiration: the Johns Hopkins Hospital experience

INTRODUCTION

Although the diagnostic utility of lymph node fine-needle aspiration (FNA) is well established in the evaluation of metastatic malignancy, its value in the diagnosis of lymphoma is more controversial; yet, there is a growing trend among practitioners towards less-invasive procedures such as FNA and core needle biopsy (CNB). The guidelines recently published by the American Society for Clinical Pathology/College of American Pathology (CAP) regarding the workup of lymphoma include recommendations on the value and limitations of FNA.

MATERIALS AND METHODS

We reviewed 1237 image-guided lymph node aspirates from 695 procedures (410 nodes from 360 ultrasound [US]-guided cases, 799 from 309 endobronchial ultrasound [EBUS], 25 from 23 endoscopic ultrasound [EUS], and 3 from 3 computed tomography [CT]).

RESULTS

The majority (40 of 46, 87%) of lymph nodes suspected of lymphomatous involvement were aspirated under ultrasound. Core needle biopsy [CNB] was obtained for 41 (89%) lymph nodes, including all 40 US specimens. Flow cytometry (FC) was performed on 37 (80%) aspirates; aspirates without FC were from patients who had a history of Hodgkin lymphoma, or showed granulomata or non-hematologic malignancy onsite. Thirty-one (67%) lymph nodes were sent for review by hematopathology. Forty-two (91%) lymph node FNA/CNB yielded actionable diagnoses. Seventeen of 241(7%) cases aspirated for other indications (14 US, 3 EBUS) were involved by a lymphoproliferative process. All were reviewed by hematopathology. All 14 US cases had FC and CNB.

CONCLUSION

Our institutional approach towards lymph node cytopathology for lymphoma workup appears to be in accordance with the new CAP guidelines, and demonstrates a potential triage and workflow model for lymph node FNA specimens that allows for accurate diagnosis in cases where lymphoma is a consideration.

Causes of necrotic features in fine-needle aspirates from cervical lymph nodes

BACKGROUND

Lymph node fine-needle aspiration (LN FNA) cytology indicates necrosis in various diseases. Dominant necrotic features make the diagnosis of underlying conditions very difficult.

METHODS

We retrospectively reviewed 460 patients who underwent cervical LN aspiration cytology that revealed necrotic findings at Keimyung University Dongsan Hospital in Daegu, Korea, from 2003-2017. Each specimen was evaluated and analyzed in association with the clinical findings, biopsy findings, and/or other ancillary tests, including acid-fast bacilli staining and molecular testing for Mycobacterium tuberculosis.

RESULTS

When necrotic features were noted upon cervical LN FNA cytology, the most common pathologic LN FNA category was necrosis alone (31.5%). The second most common category was granulomatous inflammation (31.3%), followed by Kikuchi disease (20.0%) and malignant neoplasm (8.7%). In cases where the cervical LN FNA revealed necrosis alone, the most common final diagnosis was tuberculosis. In young patients, Kikuchi disease should be considered as one cervical LN FNA category, while metastatic carcinoma should be suspected in older patients.

CONCLUSIONS

Even when necrosis alone is observed in LN FNA cytology, it is important to determine the cause through further evaluation.

Diagnostic utility of high-risk human papillomavirus mRNA in situ hybridisation in squamous cell carcinoma of unknown primary in the head and neck and implementing American Society of Clinical Oncology guideline recommendations

INTRODUCTION

The American Society of Clinical Oncology (ASCO)-endorsed College of American Pathologists guideline recommends high-risk human papillomavirus (HPV) testing for metastatic squamous cell carcinoma (SCC) of lymph nodes level II/III of unknown primary. Herein, the performance of HPV-RNA in situ hybridisation (ISH) in detection of HPV-related SCC is evaluated implementing the ASCO guideline recommendations.

METHODS

Eighty head and neck (HN) SCC fine needle aspirations, which utilized HPV-RNA ISH/P16, were evaluated at Johns Hopkins Hospital (2015-2018) to investigate their performance and concordance with histology. The results were compared to a prior study of 59 HNSCCs, which HPV-DNA ISH.

RESULTS

Of the 80 reviewed fine needle aspirations, 65 (50 male, 15 female) were included. The mean age was 63.2 ± 14.0 years. The most common site was neck lymph nodes (47, 72.3%). Fifty-five cases (84.6%) were accompanied by concurrent core biopsy, and 48 cases (59.4%) had surgical follow-ups. HPV-RNA ISH was positive in 44 (67.7%), and P16 was strongly positive in 46 (70.8%). The HPV-RNA ISH/ P16 concordance rate was 92.3% on cytology material. The cytology/surgical concordance rate for HPV-RNA ISH was 88.9% (16/18). There was a discordance between the results in five cases (7.7%; HPV-RNA ISH-/P16+).

CONCLUSION

HPV-RNA ISH is a robust and reliable method for detecting HPV-related HNSCC on cytology material showing concordance rate of 92.3% between HPV-RNA ISH and P16, which is a sensitive but non-specific marker. Compared to HPV-DNA ISH, HPV-RNA ISH reproducibly identifies HPV-related HNSCC with fewer discrepancies between cytology and histology. The findings of this study are in agreement with the ASCO recommendations.

Interpretation of HPV DNA in situ hybridization in HPV-related head and neck squamous cell carcinoma: an achievable task in cell block and small biopsy material

INTRODUCTION

Human papilloma virus (HPV)-related head and neck squamous cell carcinoma (HNSCC) is a distinct entity with a better prognosis than conventional disease. Therefore, an accurate and reproducible HPV test is needed. Herein, the analytical factors and interpretation of the HPV DNA in-situ hybridization (ISH) test are investigated.

MATERIALS AND METHODS

We evaluated 63 ultrasound-guided fine-needle aspiration (FNA) HNSCC cases for a semi-quantitative assessment of the ease of interpretation, staining pattern, and highest magnification needed for HPV DNA ISH on cell block and core biopsy.

RESULTS

A total of 72 HPV DNA ISH tests were performed in 59 (93.6%) cases. Of these, 17 had more than one HPV DNA ISH assays and 4 (6.4%) had no HPV tests. At least one HPV stain was positive in 38 (62.2%) cases. Eleven (28.95%) ISH tests were rated as difficult or moderately difficult to interpret, and 27 (78.05%) were rated as easy or moderately easy. Twenty-four (63.2%) ISH tests demonstrated strong staining and 14 (36.8%) demonstrated weak staining. Twenty-seven (71.1%) stained diffusely, and 11 (29.0%) focally. Twenty-seven ISH tests required 400× or higher magnification for interpretation. Background debris and nonspecific staining were present in 25 (35.7%) and 15 (21.4%) HPV DNA ISH cases, respectively. p16/HPV ISH was discrepant in 4 (7.3%) cases (3 P16+/HPV-, and 1 p16-/HPV+).

CONCLUSIONS

HPV DNA ISH interpretation can be challenging because of focal or weak staining, which requires careful examination at high magnification. An alternate method is needed for DNA ISH-/p16+ cases.