Fine needle aspiration diagnosis of benign oncocytic lesions of the head and neck associated with false positive 18F-fluorodeoxyglucose uptake on positron emission tomography scan.

INTRODUCTION: 18F-fluorodeoxyglucose (FDG) uptake on positron emission tomography/computed tomography (PET/CT) has become the mainstay for staging and post-therapy surveillance of cancer as malignant neoplasms generally demonstrate higher FDG uptake that benign entities. However, there are certain benign lesions, most notably oncocytic tumors, that can display very high uptake and fine needle aspiration (FNA) is usually done to confirm malignancy. Therefore, it is important to recognize that benign oncocytic lesions of the head and neck may also present as FDG-avid lesions to avoid a diagnostic pitfall. METHODS: Electronic search of institutional surgical and cytopathology archives was conducted to identify cases of benign oncocytic lesions involving the head and neck region diagnosed by FNA from January 2012 to April 2022. Chart review was used to assess whether lesions were initially discovered via PET scanning. RESULTS: One hundred and twenty-five cases of oncocytic lesions were identified; 12 (9%) PET positive lesions were identified in the head and neck region from patients being evaluated for metastasis or for suspicion of malignancy. Cytopathology of all 12 cases demonstrated benign oncocytic lesions; eight (67%) of these cases were consistent with Warthin tumor, one (8.3%) was a benign oncocytic lesion, and one (8.3%) was consistent wit a parathyroid adenoma. Most (58%) of the PET-positive lesions were in parotid region, two from thyroid gland (17%), one from submandibular gland (8%), one from paratracheal area (8%). The PET scan SUVs ranged from 3.3 to 19.5 g mL-1. CONCLUSIONS: Oncocytic lesions including Warthin tumors can result in false-positive FDG uptake on PET scans. Clinicians and cytopathologists should be aware of PET-positive benign oncocytic head and neck lesions.

Digynic monoandric triploidy in the setting of recurrent pregnancy loss: a case report and literature review.

Triploidy is a genetic occurrence in which the chromosome count is 3n = 69 with a double (2n) chromosomal contribution to the conceptus from one parent. Such pregnancies are usually nonviable and are estimated to account for approximately 1% of recognized conceptions and 10% of recognized miscarriages. Majority opinion is that fetal losses due to triploidies are caused by the presence of 2 copies of paternal chromosomes. In this study, we present a digynic monoandric triploid miscarriage from a 32-year-old G7P1051 at approximately 13 weeks gestation, in which 2 copies of the maternal chromosomes are present in the fetus. This unusual phenomenon is supported by nonmolar placental histology, chromosomal microarray, and short tandem repeat assays, with the latter 2 being discussed in detail. Furthermore, this study includes discussion of recurrent miscarriage, recurrent triploidy, and long-term clinical follow-up of the patient.

p16 Immunohistochemical Expression in Nephrogenic Adenoma.

Nephrogenic adenoma (NA) is a rare metaplastic entity commonly associated with a prior urothelial injury. Most are seen in the urinary bladder and a minority involve the urethra. In this study, we evaluated the expression of p16 as a surrogate marker of this entity and correlated it with clinical pathological parameters. A total of 17 cases of NA were retrospectively studied to assess the immunohistochemical expression of p16 and its value for the diagnosis of this entity.

Laryngeal Sarcomatoid Carcinoma With Rhabdomyoblastic Differentiation: A Potential Pitfall for Misdiagnosis As Rhabdomyosarcoma.

Sarcomatoid carcinoma (SC) of the larynx is an uncommon subtype of squamous cell carcinoma which shows both squamous carcinoma and a sarcomatous component, including heterologous elements. The presence of rhabdomyosarcomatous elements in the larynx is extremely rare. Diagnosis of SC can be particularly challenging when the malignant epithelial component is not evident. We present a case of SC in a 72-year-old man with a superficial exophytic mass in the vocal cord initially misdiagnosed as rhabdomyosarcoma due to a predominant spindle cell component with rhabdomyoblastic features by morphology and immunohistochemistry. This case report aims to increase awareness that a rhabdomyoblastic heterologous component can be present in SC of the larynx and to consider this diagnosis in a mucosal exophytic malignant spindle cell neoplasm, even in the absence of epithelial differentiation.

Nephrogenic Adenoma Arising From a Female Urethral Diverticulum: A Case Report and Potential Diagnostic Pitfalls.

Nephrogenic adenoma is a benign lesion of the urothelial tract characterized by tubules surrounded by thick, hyalinized basement membranes. There is a great variety of architectural patterns within nephrogenic adenomas, including patterns that mimic malignancy, such as focal clear or hobnail cells, areas of significant nuclear atypia, mitosis, and isolated cystic changes. This represents a diagnostic pitfall, where a malignant lesion can be mistaken for a nephrogenic adenoma, leading to a delay in diagnosis and treatment that adversely affects the outcome. In this case report, we describe a nephrogenic adenoma arising in a female urethral diverticulum and discuss the differential diagnosis, which includes clear cell carcinomas, microcystic variant urothelial carcinomas, and Skene's gland cysts.

Vacuoles in the Breast: A Histologic Clue for an Unusual Presentation of an Atypical Organism.

Infections with nontuberculous mycobacteria (NTM) are increasing in prevalence worldwide, and this group of organisms is emerging as significant clinical pathogens. We present a case of a 58-year-old female with persistent furuncles of the breast who was found to have an NTM infection. This case is unique for the lack of risk factors for NTM in the patient's history, the location of the infection in the breast, and the close cooperation needed across disciplines to arrive at the diagnosis. This multi-disciplinary discussion considers the classic clinical presentation of NTM, it is a characteristic morphological appearance on histopathology, the differential diagnosis, treatment, and the ultimate outcome of the case. This case report and discussion will assist both clinicians and pathologists in the diagnosis of this important infectious disease.

Synchronous tonsillar tumors with differing histopathology: A case report and review of the literature.

BACKGROUND: Tonsillar squamous cell carcinoma (TSCC) due to human papillomavirus (HPV) infection has seen a dramatic increase in recent years. Bilateral tonsillar squamous cell carcinoma (biTSCC) has a much lower incidence than unilateral TSCC and three main hypotheses of biTSCC pathogenesis prevail: field carcinogenesis, single-clone, and multiple HPV infections. CASE: A 49-year-old Male with a remote history of chewing tobacco presented with symptoms of spitting up tissue and occasional hemoptysis. Physical exam showed a sole left tonsillar mass which was confirmed to be TSCC on biopsy. The patient's computed tomographic (CT) scan was consistent with this finding; however, positron emission tomography (PET) scan indicated a second tumor in the contralateral right tonsil. Surgical resection of both masses and selective neck dissection was performed, and the specimens were sent for further pathological analysis. No complications of surgery were noted and the final diagnosis of synchronous biTSCC was made. The tumors were a T2N0M0 left poorly differentiated TSCC (p16+, EGFR+, bcl2+) with basaloid features, and a T1N0M0 right well to moderately differentiated TSCC (p16+, EGFR+, bcl2-). CONCLUSION: Our present case was notable for differing tumor pathology and karyotype analysis between the right and left masses, directly supporting the multiple HPV infections hypothesis of biTSCC pathogenesis. Further genetic characterization of tonsillar tumors is needed to better characterize TSCC and best guide medical/surgical therapy.

Reliability of combined fine needle aspiration and core needle biopsies in the diagnosis of liver lesions: An 8-year institutional experience.

OBJECTIVE: Fine needle aspiration (FNA), followed by core needle biopsy (CNB) when needed, was adopted as the standard care for liver lesions in our institution. This study explores the diagnostic efficacy of combined image-guided FNA and CNB in liver lesion diagnosis. METHOD: We retrospectively reviewed all liver FNA cases performed in our institution between January 2010 and September 2018. A total of 550 cases from 531 patients (173 females) with a median age of 59 years (range, 13-90) were identified. All FNA cases were initially assessed with rapid on-site evaluation, and cell blocks were prepared. A total of 459 FNA specimens with concurrent CNBs were included in the study. Both FNAs and CNBs in the paired sampling were read by a cytopathologist, with expert consultation as needed. RESULTS: The concordance rate between FNA and CNB was 85.2%. Combined FNA/CNB showed higher sensitivity in detecting malignant tumours when compared to FNA or CNB alone (98%, vs 87% and 92%, p < 0.001), especially for detecting metastatic tumours, hepatocellular carcinoma, and haematopoietic neoplasms (98%, 97%, and 94%, respectively; all p < 0.001). Combined FNA/CNB showed a lower false negative rate in malignant tumours than FNA or CNB alone (2%, vs 13% and 8%, p < 0.001). There was no significant difference among FNA, CNB, and combined FNA/CNB in diagnosing benign liver lesions. CONCLUSIONS: Combined liver FNA/CNB has high diagnostic efficacy for malignancy and a lower false negative rate than either procedure alone, especially in metastatic tumours, hepatocellular carcinoma, and haematopoietic neoplasms.

Combined large cell neuroendocrine carcinoma and squamous cell carcinoma of the oropharynx: A collision course of tumors.

Combined large cell neuroendocrine carcinoma (LCNEC) and squamous cell carcinoma (SCC) of the H&N are exceptionally rare. We present the case of combined p16 negative SCC and LCNEC of the oropharynx treated with combination chemotherapy. This is the third reported case of combined neuroendocrine carcinoma and SCC of the oropharynx.

Bilateral Cervical Pilomatricoma: A Diagnostic Dilemma for the Pediatric Otolaryngologist.

Pilomatricomas are benign skin tumors often encountered by otolaryngologists but frequently misdiagnosed. Although they can occur at any age, they commonly present in children as a discolored superficial lesion adhered to the overlying skin. Accurate preoperative diagnosis is crucial for appropriate management, which is surgical in most cases. Here, we present bilateral pilomatricomas mimicking features of several other diagnoses in a pediatric patient. The patient was successfully treated with surgical excision. This case presented a unique diagnostic challenge, as the lesions exhibited features of several common diagnoses. In general, surgical management of pilomatricoma is curative, and recurrence is rare.

Outcome of atypia of undetermined significance/follicular lesion of undetermined significance in thyroid fine-needle aspirations: A six-year institutional experience.

BACKGROUND: Atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) is one of six diagnostic categories of The Bethesda System for Reporting Thyroid Cytopathology (BSRTC). The goal of our study is to assess the outcome of cases classified as AUS/FLUS at our institution. METHODS: AUS/FLUS cases were identified by computer searching of the thyroid fine-needle aspiration (FNA) cases performed between 2010 and 2016. Outcomes were categorized as: follow-up surgery, repeat FNA or no follow-up available. Demographics, ultrasound findings and FNA diagnostic criteria were reviewed for AUS/FLUS cases with follow-up surgical pathology diagnosis. RESULTS: Our AUS/FLUS thyroid FNA rate was 6% (117 out of 1984 FNAs). Only 15% of the AUS/FLUS cases had repeat FNA, while 41% underwent surgery. The risk of malignancy (ROM) for cases with follow-up surgery was 17%. When considering all AUS/FLUS cases, the ROM was 7%. Statistically, benign neoplasms were more likely to be single lesions on ultrasound comparing to malignant neoplasms, and to exhibit architectural atypia as opposed to non-neoplastic lesions on FNA. The malignancy rates among patients that directly went to surgical resection (17%) and patients having repeat FNA after the first AUS/FLUS diagnosis followed by surgery (29%) was not significantly different. However, repeat FNA was able to reclassify the majority of cases into more definitive categories. CONCLUSION: The outcome of the thyroid FNAs diagnosed as AUS/FLUS in our institution meets the benchmark statistics for AUS/FLUS rate and ROM. This study constitutes a valuable quality assurance measure and serves as a baseline for subsequent quality improvement.

Role of fine-needle aspiration cytology in early diagnosis of fungal infections.

BACKGROUND: Fine-needle aspiration (FNA) is an important tool for the diagnosis of infectious diseases. In this study, we assessed the efficacy of FNA cytology in early diagnosis of fungal infections. METHODS: This was a retrospective study from January 2016 to August 2018. Electronic archives were searched for FNAs from superficial and deep lesions obtained from various sites with the diagnosis of fungal infection. Each case was evaluated for underlying predisposing conditions, FNA source, radiologic findings, culture, and serology results. RESULTS: A total of 15 cases were identified from the following sites: lung (eight), cervical lymph nodes (four), soft tissue (two), and retroperitoneal lymph node (one). Predisposing conditions were found in 11 patients: HIV (five), malignancy (three), and post-transplant (three). Imaging impression was mostly malignancy vs infection. In all 15 cases, the diagnosis of fungal infection was done by FNA cytology. The presumptive genus specific diagnoses based on yeast morphology was given in 12 cases (five Histoplasma, four Cryptococcus, and three Coccidioides). The diagnosis of fungal infection was provided within 24 h in nine cases, four during onsite evaluation. Microbial cultures were confirmatory in seven cases, and five cases exhibited negative cultures with positive serology. Out of the 15 patients, 14 were discharged in fair condition, and one died with complications of heart graft failure. CONCLUSION: FNA is a rapid and reliable method for early diagnosis of fungal infections, allowing a prompt and appropriate management, especially in immunocompromised patients. When onsite evaluation indicates infectious process, cultures can be timely done.

Salivary gland fine-needle aspiration cytology with the application of the Milan system for risk stratification and histological correlation: A retrospective 6-year study.

BACKGROUND: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is based on risk stratification. We presented our experience with fine-needle aspiration cytology (FNAC) for the diagnosis of salivary glands lesions by applying the MSRSGC categorization to the cytological diagnoses, and determined risk of malignancy (ROM) for each category. METHODS: Fine-needle aspiration cytology of salivary gland lesions performed over a 6-year period was retrieved. FNAC results were retrospectively categorized according to the MSRSGC criteria, and correlated with corresponding histologic follow-up. ROM for each diagnostic category was calculated. RESULTS: A total of 208 FNAC of salivary gland lesions were reviewed and retrospectively categorized as: non-diagnostic (ND) 23 (11%), non-neoplastic (NN) 54 (26%), atypia of undetermined significance (AUS) 10 (4.8%), benign neoplasms (BN) 77 (37%), salivary gland of uncertain malignant potential (SUMP) 13 (6.3%), suspicious for malignancy (SM) 7 (3.4%), and malignant (M) 24 (11.5%). Histopathological follow-up was available for 84 of 208 cases (40.4%). Overall concordance rate between FNAC and histology was 78.8%. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated as 93.3%, 94.6%, 82.4%, and 98.2%, respectively. Diagnostic accuracy to distinguish benign from malignant disease was 94.4%. ROM for each category was ND 0%, NN 0%, AUS 75%, BN 2.2%, SUMP 28.6%, SM 50%, and M 100%. CONCLUSION: Fine-needle aspiration cytology continues to be an accurate diagnostic tool for most salivary gland neoplasms showing classical morphologic features. However, difficult cases with unusual or overlapping features will occur. In these situations, the use of MSRSGC risk-stratification could be helpful to define appropriate management.

Abdominal Wall Clear Cell Carcinoma: Case Report of a Rare Event with Potential Diagnostic Difficulties.

Clear cell carcinoma (CCC) is a well-known aggressive histological type of carcinoma, predominantly seen in ovary and endometrium. However, CCC arising in abdominal wall is a very rare event. We report a case of a 48-year-old woman with an abdominal wall mass at her cesarean section (c-section) scar, which increased in size and became painful in the last months. Radiology revealed a 7 cm mass in the right inferior rectus muscle sheath, suggestive of endometriosis. An irregular, firm mass was resected, densely adherent to the rectus muscle and pubic bone. Frozen section revealed a multicystic lesion with minimal cytologic atypia, and a benign cystic neoplasm was favored. However, permanent sections showed marked nuclear atypia, hobnail morphology, and areas of infiltrative growth within fibrous stroma. No benign endometrial glands were found, although fibrosis and hemorrhage were present. Napsin-A, racemase, and PAX-8 were positive, consistent with CCC, likely arising within a c-section endometriosis focus. Although CCC usually presents with moderate to marked nuclear atypia, it can be mild and, especially in cases with a predominant cystic pattern, create diagnostic difficulties. An endometriosis-associated malignancy should be considered in the differential with any enlarging nodule or increasing pain within an abdominal wall scar.

Plexiform Schwannoma of the Tongue in a Pediatric Patient with Neurofibromatosis Type 2: A Case Report and Review of Literature.

INTRODUCTION: Plexiform schwannoma is a rare variant of schwannoma that accounts for only 5% of all schwannomas. Herein, we present a rare case of plexiform schwannoma of the tongue in a pediatric patient with neurofibromatosis type 2 (NF2). CASE PRESENTATION: A 13-year-old female presented with a growing left-sided tongue mass. The patient has a past medical history of NF2. The tongue mass was excised and histopathological examination revealed a spindle cell tumor with multinodular growth pattern, with Verocay bodies' formation. Tumor cells were strongly positive for S-100 protein and negative for smooth muscle actin (SMA), and EMA highlighted perineural fibroblasts surrounding tumor nodules. These findings were diagnostic of plexiform schwannoma. CONCLUSION: Plexiform schwannoma of the tongue is an extremely rare tumor seen in patients with NF2. Clinical examination and histopathological evaluation are important for diagnosis of plexiform schwannoma.

Vaginal Bleeding as Initial Presentation of an Aggressive Renal Cell Carcinoma: A Case Report and Review of the Literature.

INTRODUCTION: Renal cell carcinoma is the third most common urogenital cancer. In some patients, it can metastasize to distant organs. Metastasis to the vagina is extremely rare. CASE PRESENTATION: A 54-year-old female with unremarkable history presented to the clinic with a chief complaint of vaginal bleeding. Further examination identified a pedunculated mass on the vaginal wall. Histologic examination revealed a metastatic clear cell renal cell carcinoma. Radiological studies then revealed a left renal mass and bilateral adrenal masses. The patient underwent a nephrectomy, adrenalectomy, and resection of the vaginal mass. The mass in the vagina has since recurred. CONCLUSION: We report the first known case of vaginal metastasis as initial presentation of a renal cell carcinoma with rhabdoid features. Postmenopausal women with renal cell carcinoma who present with vaginal bleeding should undergo a thorough inspection of the vaginal wall for the potential of metastatic neoplasms.

Myopericytoma of the Lip: A Case Report of This Rare Lesion.

Myopericytomas are rare benign tumors that show a distinctive, concentric perivascular proliferation of oval to spindle-shaped myoid-appearing cells that are predominantly arranged concentrically around thin-walled vascular channels. These lesions are similar in histologic appearance to hemangiopericytomas, myofibromas, and glomus tumors. The myopericytoma is usually found in the distal extremities, but a handful of reports have shown the lesion to be present in the oral cavity. A review of the literature to date shows only 4 other reported cases of myopericytomas occurring in the lips. We describe a case of myopericytoma in the lower lip of a 42-year-old woman.

Correlation of microbiologic culture and fine-needle aspiration cytology: A 14-year experience at a single institution.

BACKGROUND: Fine-needle aspiration (FNA) is an important tool for the diagnosis of infectious disease. FNA material should be appropriately submitted for cultures when indicated by preliminary findings. Correlation of cytologic diagnoses with culture results are important quality assurance tools. The current study reviewed 14 years of FNA-culture correlation. METHODS: FNA cytology-culture correlation records from the years 1996 through 2007 and 2010 through 2011 were retrieved from electronic databases compiled for histology and culture correlation. Correlation was limited to those cases for which material was submitted for culture from the FNA sample. Culture results were retrieved from the laboratory or hospital information system. RESULTS: Correlative data included 770 cases. Cytology, culture, or both were positive for microbes in 416 of 770 samples (54%), excluding cultured bacterial skin contaminants. Among the 204 bacteria cases, 93 (46%) were identified by cytology and culture, 92 (45%) were identified by culture only, and 19 (9%) were identified by cytology only. Among the 16 cases of Actinomycetales, 8 (50%) were identified by cytology and culture, 5 (31%) were identified by culture only, and 3 (19%) were identified by cytology only. Of the 129 cases of mycobacteria, 63 (49%) were identified by cytology and culture, 44 (34%) were identified by culture only, and 22 (17%) were identified by cytology only. Among the 67 cases of fungi, 34 (51%) were identified by cytology only, with 15 of these 34 cases being fungal hyphae; 25 cases (37%) were identified by cytology and culture, with a 100% concordance between the cytology diagnosis and culture result; and 8 cases (12%) were identified by culture only. CONCLUSIONS: FNA cytology-culture correlation is a valuable tool with which to assess the efficacy and limitations of the direct diagnosis of infectious agents, and to identify types of infections that may be negative on culture but positive on cytology diagnosis.