Thyroid cancer necrosis not evident on imaging: A cautionary case series on poorly differentiated thyroid carcinoma diagnosed only on final pathology.

OBJECTIVE: Poorly-differentiated thyroid cancer (PDTC) is a highly aggressive malignancy which is recently defined and understudied in the radiologic literature. Necrosis is a key histopathologic criterion for the diagnosis of PDTC. We illustrate the current difficulty in accurate identification of histopathologic necrosis on preoperative imaging. METHODS: A series of seven patients with the final diagnosis of PDTC from our institution were identified. Multimodality preoperative imaging was analyzed by two head and neck radiologists. Final pathology reports were queried confirming histopathologic evidence of necrosis. RESULTS: Patients presented with a wide range of preoperative imaging features. A consistent imaging appearance confirming necrosis was not identified. All patients were subsequently upstaged to PDTC following final pathological analysis. CONCLUSION: A lack of definitive evidence of necrosis on preoperative imaging does not exclude the possibility of PDTC. We demonstrate the need for further research to establish a clear methodology for the preoperative diagnosis of PDTC.

Functional loss of tumor suppressor genes detected by loss of heterozygosity, but not driver mutations, predicts aggressive lymph node status in papillary thyroid carcinoma.

BACKGROUND: Recognizing aggressive tumor biology is essential to optimizing patient management for papillary thyroid carcinomas (PTC). Aggressive lymph node (ALN) status is one feature that influences decision-making. We evaluated genomic deletions in regions of tumor suppressor genes, detected by loss of heterozygosity (LOH) analysis, to understand causal alterations linked to thyroid cancer aggressiveness and to serve as a molecular diagnostic biomarker for ALN status. METHODS: We analyzed 105 primary PTC enriched for patients with ALN (64% with, 36% without). We also analyzed 39 positive lymph nodes (79% with, 21% without ALN). LOH was determined using a panel of 25 polymorphic microsatellite alleles targeting 10 genomic loci harboring common tumor suppressor genes. Additionally, ThyGeNEXT® and ThyraMIR® assays were performed. RESULTS: LOH was detected in 43/67 primary PTC from patients with ALN status, compared with only 5/38 primary PTC without ALN (minimal metastatic burden) (P=0.0000003). This is further supported by post hoc analyses of paired primary and metastatic samples. Paired samples from patients with ALN are more likely to harbor LOH, compared to the ALN negative group (P=0.0125). Additionally, 12/31 paired samples from patients with ALN demonstrated additional or different LOH loci in metastatic samples compared to the primary tumor samples. No association was seen between ALN and mutational, translocation, or microRNA data. CONCLUSIONS: LOH detected in primary PTC significantly predicts ALN status. Analysis of paired primary and metastatic samples from patients with / without ALN status further supports this relationship. The acquisition of LOH at additional loci is common in lymph nodes from patients with ALN status. SIMPLE SUMMARY: A subset of patients with papillary thyroid carcinoma (PTC) will develop recurrent disease. One known predictor of recurrence is the American Thyroid Association category "Aggressive Lymph Node" (ALN) disease, considering metastatic burden. Loss of heterozygosity (LOH) - chromosomal loss in regions of tumor suppressor genes - has yet to be investigated as a possible mechanism driving ALN status in PTC. The ability to predict ALN status prior to surgery can guide the extent of surgery and postoperative treatment options. We found that paired samples from patients with ALN are more likely to harbor LOH, compared to patients without ALN disease. 38% of patients with ALN demonstrated additional or different LOH loci in metastatic samples compared to the primary tumor samples. LOH complements current molecular analysis of thyroid cancer when searching for evidence of aggressive biology.

Synchronous thyroid cancer and malignant struma ovarii: concordant mutations and microRNA profile, discordant loss of heterozygosity loci.

BACKGROUND: Struma ovarii is an unusual ovarian teratoma containing predominantly thyroid tissue. Less than 10% of cases undergo malignant transformation in the thyroid tissue and are considered malignant struma ovarii (MSO). MSO have been reported with concurrent thyroid lesions, but molecular data is lacking. CASE PRESENTATION: A 42-year-old female developed MSO and synchronous multifocal subcentimeter papillary thyroid carcinoma (PTC). The patient underwent a salpingo-oophrectomy, thyroidectomy, and low-dose radioactive iodine ablation. Both the thyroid subcentimeter PTC and MSO were positive for BRAF V600E mutation, and microRNA expression profiles were similar across all tumor deposits. However, only the malignant component demonstrated extensive loss of heterozygosity (LOH) involving multiple tumor suppressor gene (TSG) chromosomal loci. CONCLUSIONS: We present the first reported case of MSO with synchronous multifocal subcentimeter PTC in the thyroid containing concordant BRAF V600E mutations and resulting with discordant LOH findings. This data suggests that loss of expression in tumor suppressor gene(s) may be an important contributor to phenotypic expression of malignancy.

WPOI-5: Accurately Identified at Intraoperative Consultation and Predictive of Occult Cervical Metastases.

BACKGROUND: Frozen section analysis of oral cancer specimens is ideal for assessing margin distances and depth of invasion (DOI); the latter impacts intraoperative decisions regarding elective neck dissection (END). Here, we show that intraoperative determination of worst pattern of invasion (WPOI), specifically WPOI-5, has a high level of accuracy. This relates to our demonstration herein that WPOI-5 predicts occult cervical metastases (OCM) for pT1 oral squamous carcinoma (OSC). METHODS: The presence of OCM was correlated with WPOI in 228 patients with primary T1/T2/cN0 OSC undergoing resection and END. Concordance between intraoperative and final pathology WPOI determination was assessed on 51 cases of OSC. RESULTS: WPOI-5 predicts OCM in pT1 patients, compared with WPOI-4/WPOI-3 (p < 0.0001). Most pT1 WPOI-5 tumors had DOI of 4-5 mm (24/59 or 40.7%). Only two pT1 WPOI-5 tumors had DOI < 4 mm (3.0 and 3.5 mm). If END were performed in this pT1 cohort for all WPOI-5 OSC patients regardless of DOI, OR all OSC patients with DOI ≥ 4 mm regardless of WPOI, then no OCM would be missed (p = 0.017, 100% sensitivity, 29% specificity, 77% positive predictive value, 23% negative predictive value). With respect to intraoperative WPOI-5 determination, the accuracy, sensitivity, and specificity was 92.16, 73.33, and 100.0%, respectively. CONCLUSIONS: DOI ≥ 4 mm is the dominant predictor of OCM. For the rare WPOI-5 OSC with DOI < 4 mm, it is reasonable to suggest that surgeons perform END. WPOI-5 may be accurately determined intraoperatively. As microscopic instruction is needed to accurately assess WPOI-5, a teaching link is included in this manuscript.

Extratumoral invasion: A unique phenomenon of aggressive recurrent oropharyngeal squamous cell carcinoma.

BACKGROUND: Oropharyngeal squamous carcinomas cause significant morbidity and mortality. Poor prognosticators include lymphovascular and perineural invasion. Extratumoral phenotypes of these histologic findings confer worse prognoses. METHODS: We report eight cases of recurrent oropharyngeal cancer with diffuse extratumoral lymphovascular invasion (ELVI) or extratumoral perineural invasion (EPNI) and review the existing literature. RESULTS: On salvage resection for recurrence following primary radiation or chemoradiation, six patients manifested ELVI and two showed EPNI. These patterns conferred difficulty with complete surgical clearance; final pathologic analysis demonstrated positive margins for all eight patients. The six patients with ELVI were p16+ and the two with EPNI were p16-. Currently, two patients are deceased and six patients are alive at an average follow-up of 17.4 months. Of the six living patients, 2 have a new recurrence and are in hospice while 4 have no evidence of disease. CONCLUSIONS: ELVI and EPNI have received little consideration in the literature as unique histopathologic features of oropharyngeal squamous carcinoma. We present the first series on these adverse extratumoral features in recurrent disease. We call attention to these unique histologic features in the setting of recurrent oropharyngeal cancer to encourage others to track the results of therapeutic intervention and to identify successful strategies for treatment.

Tall cell variant papillary thyroid carcinoma impacts disease-free survival at the 10 % cut-point on multivariate analysis.

INTRODUCTION: The diagnosis of tall cell variant papillary thyroid carcinoma (TCV-PTC) corresponds to the feature of "aggressive histology" within the framework of the American Thyroid Association (ATA) Risk of Recurrence (ROR) guidelines. Using the current World Health Organization (WHO) definition for TCV-PTC (tall cells with height at least twice the width, distribution ≥ 30 %), we examined the impact of this diagnosis on disease-free survival (DFS). METHODS: The study cohort consisted of 347 patients treated for primary papillary thyroid carcinoma (PTC). Current ATA guidelines were followed for the extent of surgery and the administration of adjuvant radioiodine therapy. Clinical surveillance included ultrasound examination and biochemical parameters according to ATA standards. The outcome was measured as time from surgery to first disease recurrence (DR) versus time from surgery until the last documented disease-free encounter (no evidence of disease, NED). Disease-free patients with fewer than 6 months of follow-up were excluded from this cohort. Structural recurrences are documented by histology or cytology whereas biochemical recurrences are documented by rising serum thyroglobulin in the absence of structural disease. All slides on all patients were examined by two pathologists with the substantial interobserver agreement (Kappa = 73 %). The primary tumors are categorically classified either as (1) TCV-PTC (definition above), (2) Papillary thyroid carcinoma with tall cell features (PTC-TCF) (≥ 10 % < 30 % tall cells), or (3) Control (< 10 % tall cells). Tumor size is categorized as either (1) ≤ 10 mm, (2) 11-29 mm, or (3) ≥ 30 mm. Degree of ETE is categorized as either intrathyroidal, microscopic ETE, histologic spread to strap muscles, or pT4 disease. RESULTS: 185 patients are classified as TCV-PTC (≥ 30 % tall cells), 62 as PTC-TCF (≥ 10 % < 30 % tall cells), and 100 as control group (< 10 % tall cells). TCV-PTC is associated with ≥ 30 mm size (p = .0246) and invasion of strap muscles and/or pT4 (p = .0325). There was no relationship between TCV-PTC and aggressive lymph node (ALN) status defined by ATA. Overall follow-up ranged from two months (one patient death) to 203 months (mean 40.8, median 33.0). DR occurred in 61 patients (mean 31.4 months, range 0 -184, 59 structural recurrences, 2 biochemical recurrences). Three models for TCV-PTC were examined: Model 1 - Tall cells ≥ 10% versus control, Model 2 - TCV-PTC versus TCF-PTC versus control, and Model 3 - TCV-PTC versus control. Kaplan Meier curves demonstrated decreased DFS with ALN status (p = .0001), ETE (p = .0295), and TCV-PTC (Model 1, p = .041). On multivariate analysis, TCV-PTC (Model 1) remained significantly predictive when adjusted for ALN (p = .0059). ETE dropped out of the model. CONCLUSION: TCV-PTC is significantly associated with larger tumors and a greater degree of ETE. The diagnosis of TCV-PTC significantly impacts DFS at the 10 % cut-point on multivariate analysis.

Oncocytoid Variant of High-Grade Salivary Duct Carcinoma: A Potential Diagnostic Pitfall. A Report on Two Patients.

Salivary duct carcinoma (SDC) is an uncommon and aggressive salivary malignancy. The oncocytoid variant of salivary duct carcinoma (OSDC) has only been reported in the English literature once before. Here we detail two new patients. A 71-year-old female presented with a painless enlarging left parotid mass. Imaging and fine-needle aspiration were nondiagnostic. The second patient, a 79-year-old male, presented with painless swelling in the right cheek. Imaging was nondiagnostic. Both patients underwent surgical resection. Histopathology revealed bland yet infiltrative OSDC in both cases. These tumors were AR+ (androgen receptor) by immunohistochemistry. Potential difficulty exists in distinguishing the oncocytoid variant of SDC, a rare and relatively bland tumor, from oncocytoma, a more commonly encountered entity. AR expression can aid in the correct diagnosis.

Cuneiform (cuniculatum) variant of oral squamous cell carcinoma revisited: Presentation of two cases and literature review of a rare entity.

BACKGROUND: Oral carcinoma cuniculatum (OCC) is a rare, locally aggressive tumor, which tends to invade underlying bone. We present two cases of OCC, one demonstrating invasion of the mandible and the other limited to the tongue. METHODS: An 87-year-old male presented with a right-sided buccogingival lesion. Biopsy results led to a diagnosis of verrucous hyperplasia, which was later revised to OCC. Additionally, a 94-year-old female presented with a left lateral tongue lesion. A biopsy showed in-situ and invasive keratinizing squamous cell carcinoma that was later defined as a soft tissue OCC. RESULTS: Following surgical resection, the diagnosis of OCC was established in both patients. We provide a comprehensive literature review of OCC in the context of both case presentations. CONCLUSIONS: OCC is a rare entity, which has a tendency to be misdiagnosed. We emphasize the importance of recognizing the common features of OCC in order to aid in accurate diagnosis.

Orbital invasion by Esthesioneuroblastoma: a comparative case series and review of literature.

PURPOSE: To review the current literature on esthesioneuroblastoma (ENB) as it pertains to clinical features, grading systems, treatment options, and survival. METHODS: A literature search in PubMed was performed to include all articles published in English with orbit involving ENB. Only articles that included each patient's demographics, tumor stage, treatment, or survival were included. A total of 22 articles with 104 patients were considered for this literature review. We also present five cases of ENB, all encountered in our health system, between 2010 and 2020. RESULTS: The median age of diagnosis of orbit involving ENB was 44.5 years. Males were more likely affected than females at 72.9%. Common presenting ocular symptoms were visual change (38.1%), periorbital pain (33.3%), and diplopia (14.3%). Common clinical exam findings were proptosis (47.6%), extraocular movement deficit (23.8%), and periorbital edema (19.0%). Twenty-seven patients (77.1%) received surgery, 22 patients (62.9%) received chemotherapy, and 30 patients (85.7%) received radiation therapy as part of their treatment. Median duration of survival was 124.0 months and 5-year overall survival (OS) was 67.1%. Hyams, Kadish, and Dulguerov T-staging showed inconsistent survival prognosis while orbital invasion and lymph node metastasis had worse outcomes. Our five cases exhibited the spectrum of disease processes evidenced above, with four involving the orbit. CONCLUSIONS: ENB is a rare sinonasal tumor that can invade the orbit. Because of its rarity, no single staging system appears superior. Resection with radiation therapy has superior survival results while the benefits of chemotherapy are currently unknown.

Adenoid Cystic Carcinoma of the Gingiva: A Case Report and Literature Review.

OBJECTIVES: Adenoid cystic carcinoma (ACC) is a commonly encountered salivary gland malignancy. However, it rarely occurs in the gingiva, an area generally thought to be devoid of minor salivary glands. We present a case occurring in this unusual site and review other reported cases. METHODS: A 56 year-old male presented with a right-sided mandibular toothache for 1 year and underwent dental extraction. Due to persistent pain, follow up examination revealed a large gingival lesion. A biopsy was positive for adenoid cystic carcinoma. RESULTS: The patient underwent a complete right segmental mandibulectomy and was reconstructed with a fibular osteocutaneous free flap. Three months postoperatively, during the planning for adjuvant radiation therapy, the patient developed pain in the left mandible. Imaging revealed extensive involvement of the left native mandible. Deep bone biopsies in several areas of the left mandible revealed ACC. He then underwent a complete left hemi-mandibulectomy and reconstruction with a fibular osteocutaneous free flap. Tensor fascia lata suspension slings were placed due to concern for an open mouth deformity attributable to disruption of bilateral masticator slings. He will undergo adjuvant radiation therapy. Our review of the literature revealed 50 cases of gingival ACC published since 1972. Disease recurrence and distant metastases were noted in several patients, occurring at the latest after 30 years follow-up. CONCLUSIONS: Given its indolent behavior, high proclivity for late recurrence and metastasis, and overall infrequency, ACC represents a pathology that requires early diagnosis and comprehensive long-term surveillance. While ACC is well described in oral cavity sites with high densities of minor salivary glands, it is not commonly seen in the gingiva. As such, gingival ACC may display a unique biological and/or clinical character. We offer the first literature review of this rare entity.

Rare case of anaplastic plasmacytoma in the sinonasal tract.

BACKGROUND: Extramedullary plasmacytomas are tumors that develop from plasma cells and rarely express anaplastic features. To our knowledge, there have only been three reported cases of anaplastic plasmacytomas of the sinonasal tract in the English literature. We detail the fourth case. METHODS: A 70-year-old male was seen with a 4-month history of nasal congestion, bloody mucous, and left sided nasal obstruction. On positron emission tomography/computed tomography, the lesion was FDG-avid with an SUVmax of 25.1. A biopsy of the lesion and subsequent immunohistochemical staining confirmed the diagnosis of an anaplastic plasmacytoma. RESULTS: The patient is undergoing a 5-week course of curative-intent radiation therapy. CONCLUSION: Extramedullary plasmacytomas with anaplastic features are very rare. We highlight the value of thorough histopathological review and detailed immunostains to arrive at a diagnosis of anaplastic extramedullary plasmacytoma.

First reported PET positive, FDG avid free flap pedicle ossification and review of the literature.

The fibular free flap (FFF) is commonly used for head and neck bony reconstruction. Ossification of the vascular pedicle has been reported but is an uncommon complication of this procedure. Ossification of the pedicle with FDG avidity has not been identified in the literature. Here we present a case of FDG avid free flap ossification seen on PET/CT imaging in a patient who developed trismus after fibular free flap reconstruction of a maxillary defect for a primary squamous cell carcinoma of the palate. The FDG avidity of the free flap ossification and trismus were both concerning for recurrent squamous cell carcinoma.

Rare case of metastatic liposarcoma to the thyroid gland and a review of the literature of metastatic sarcomas to the thyroid.

BACKGROUND: Liposarcomas are the second most common type of soft tissue sarcomas. Typically, myxoid liposarcomas have a metastatic rate of 10%, usually involving the retroperitoneal space, abdomen, and spine. Metastasis to the thyroid is extremely rare. DESIGN/METHOD: A 62-year-old male with a history of metastatic myxoid liposarcoma in his right thigh presented to our clinic for evaluation of a thyroid nodule incidentally identified on a CT scan. A subsequent FNA biopsy was suggestive of a metastatic liposarcoma. RESULTS: The patient underwent a left thyroid lobectomy and final pathology confirmed a grade II/III metastatic myxoid liposarcoma that measured 3.3 cm. The patient tolerated the procedure well. CONCLUSIONS: Our case highlights the role of a patient's medical history when evaluating thyroid nodules to optimize accurate diagnosis, as liposarcomas do not typically metastasize to the thyroid. We also provide an updated review of the literature on all cases of metastatic sarcomas to the thyroid.

Extraskeletal Ewing sarcoma of the buccal space.

Extraskeletal Ewing sarcoma (EES) is a rare soft tissue tumor, and EES of the head and neck is particularly rare. Radiographic imaging of these lesions is crucial given their anatomical complexity and infrequent incidence. Conventional EES imaging features include a large, hyperintense, heterogeneously enhancing lesion, with frequent invasion of local structures. In this case report, a 19-year old male presented with left facial swelling and pain. He underwent sclerotherapy and bleomycin treatment for a presumed lymphatic malformation. Initial imaging demonstrated a rim-enhancing lesion within the left buccal space with no muscle invasion or bony erosion present. Two years later, imaging identified an enlarging buccal mass with destruction of the zygomatic arch and inferolateral orbital wall. The patient underwent surgical resection of the mass. Pathology confirmed the mass to be a small round blue cell tumor and FISH testing confirmed the presence of the EWSR1 gene arrangement that is consistent with EES. The patient tolerated the procedure well and underwent chemoradiation therapy. At three years postoperatively, the patient remains disease free. The presented case demonstrates an unusual presentation of a buccal space EES as a rim-enhancing, centrally hypointense mass with no bony erosion or muscular invasion. The location and atypical imaging appearance of this case offer insight for future diagnosis of EES.

Educational Case: Testicular Germ Cell Tumor: Clinical Presentation, Pathogenesis, and Diagnostic and Therapeutic Modalities.

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040.1.

Educational Case: Urothelial Carcinoma: An Overview of Pathologic Diagnosis.

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040.1.

When accurate cytomorphology directs clinical decision: Colonic adenocarcinoma presents initially with an isolated vertebral bone metastasis.

Liver is the most common site for metastasis of colonic adenocarcinoma. Other relatively common metastatic locations include: peritoneum, lungs and ovaries. Rare metastatic sites include: central nervous system, testis, uterus, oral cavity and bones. Though it is rare to have an isolated bone metastasis without liver or visceral involvement in colonic adenocarcinoma, it can occur. Our case illustrates the vital role of an accurate cytopathologic diagnosis in directing the proper clinical decision and management in our young patient. Our patient's first presentation was acute on chronic back pain radiating to his lower extremities with clinical suspicion of tuberculosis spondylitis. The correct cytopathologic diagnosis of the fine needle aspiration from the destructive vertebral lesion led to the establishment of an isolated metastatic colonic adenocarcinoma diagnosis initially and directed the clinical management of our patient.

Safety during crisis: Rapid on-site evaluation at the time of COVID-19 pandemic.

The COVID-19 pandemic is posing a worldwide challenge to control and contain. SARS-CoV-2 is a highly infectious virus. Health care providers at the front lines are at high risk of getting the infection and the risk applies also to laboratory personnel as they deal with specimens that might be contaminated with infectious materiel. Cytopathology teams specifically are at high risk of dealing with contaminated material because of patients encounter during fine-needle aspiration biopsies or Rapid On-Site Evaluation (ROSE) for adequacy. In our article, we discuss alternative safer staining methods to the widely used Diff-Quick stain that can be utilized for ROSE to decrease the risk of viral exposure during the current COVID-19 pandemic.