Modeling aging and retinal degeneration with mitochondrial DNA mutation burden.

Somatic mitochondrial DNA (mtDNA) mutation accumulation has been observed in individuals with retinal degenerative disorders. To study the effects of aging and mtDNA mutation accumulation in the retina, a polymerase gamma (POLG) exonuclease-deficient model, the PolgD257A mutator mice (D257A), was used. POLG is an enzyme responsible for regulating mtDNA replication and repair. Retinas of young and older mice with this mutation were analyzed in vivo and ex vivo to provide new insights into the contribution of age-related mitochondrial (mt) dysfunction due to mtDNA damage. Optical coherence tomography (OCT) image analysis revealed a decrease in retinal and photoreceptor thickness starting at 6 months of age in mice with the D257A mutation compared to wild-type (WT) mice. Electroretinography (ERG) testing showed a significant decrease in all recorded responses at 6 months of age. Sections labeled with markers of different types of retinal cells, including cones, rods, and bipolar cells, exhibited decreased labeling starting at 6 months. However, electron microscopy analysis revealed differences in retinal pigment epithelium (RPE) mt morphology beginning at 3 months. Interestingly, there was no increase in oxidative stress and parkin-mediated mitophagy in the ages analyzed in the retina or RPE of D257A mice. Additionally, D257A RPE exhibited an accelerated rate of autofluorescence cytoplasmic granule formation and accumulation. Mt markers displayed different abundance in protein lysates obtained from retina and RPE samples. These findings suggest that the accumulation of mtDNA mutations leads to impaired mt function and accelerated aging, resulting in retinal degeneration.

Two cases of imatinib induced oral pigmentation affecting the palate.

BACKGROUND: Medication-related oral pigmentation is a unique yet benign finding in the dental setting. As new antineoplastic agents emerge, it is likely that this documented manifestation will continue to grow. CASE DESCRIPTION: Here, we describe two case presentations of imatinib-related hyperpigmentation of the palate. Both patients had been on imatinib, an antineoplastic agent for 10-14 years and presented with asymptomatic diffuse blue-black discoloration of the hard palate. Both cases demonstrated biopsy-proven pigment changes localized to the superficial connective tissue with evidence of melanin and hemosiderin deposits. Of note, this is a benign finding that does not require intervention. CONCLUSION: These two cases illustrate intraoral findings associated with imatinib. Increased awareness of this side effect will enable clinicians to appropriately council patients regarding the benign nature of this process.

The Novel Cytokine Interleukin-41/Meteorin-like Is Reduced in Diffuse Systemic Sclerosis.

Systemic sclerosis (SSc) is an autoimmune connective tissue disease with a triad of features that include vascular abnormalities, inflammation and skin and lung fibrosis. At the core of the disease is the activation of myofibroblasts from quiescent fibroblasts and this can be modified by various cytokines. IL-41 is a recently described cytokine that was initially characterised as an adipokine as it was highly expressed in adipocytes and adipose tissue. However, it has recently been identified as being widely expressed and has immunomodulatory functions. This study examined the circulating levels of IL-41 and its expression in skin biopsies. We demonstrated significantly reduced levels of IL-41 in diffuse SSc that was also mirrored in the skin of SSc patients. AMPK has been proposed as a downstream target of IL-41, so we also measure mammalian target of rapamycin in skin and found that this is elevated in SSc patients. We speculate that IL-41 maybe an antifibrotic cytokine and its reduction may facilitate the activation of fibroblasts.

Malakoplakia Involving the Maxilla: A Case Report and a Review of the Literature.

Malakoplakia is a rare inflammatory disorder which typically occurs in immunocompromised patients secondary to impaired bactericidal activity of macrophages. While this entity commonly arises in the genitourinary and gastrointestinal tracts, lesions of the head and neck have been reported only rarely, with oral cavity involvement reported in 3 cases. The most common presentation of head and neck malakoplakia is that of a cutaneous flesh-colored papule or nodule. This case report, however, illustrates the first time malakoplakia is identified affecting the maxilla and maxillary alveolar ridge mucosa. Histochemical and immunohistochemical stains are presented and include positivity for PAS, von Kossa stain, iron stain, and CD68 and negativity for GMS and Gram stains, indicating an inability to demonstrate microbial infection. Thus, clinicians and pathologists alike should be aware of malakoplakia as a pathologic entity when forming differential diagnoses, particularly in immunosuppressed individuals.

Dysgenetic Polycystic Disease of the Salivary Glands: A Case Report of This Rare Entity Occurring for the First Time in the Minor Salivary Glands of the Tongue, and a Review of the Literature.

Dysgenetic polycystic disease, also known just as polycystic disease, is a very rare developmental abnormality affecting the salivary gland duct system. This entity has been reported in only 21 patients previously, although a careful review suggests only 16 patients have histological evidence of the disease. In previously reported cases, this lesion most commonly presents as either an incidental finding or as a swelling affecting the parotid glands bilaterally, or rarely the submandibular glands bilaterally. This case report details the first time dysgenetic polycystic disease is found affecting the minor salivary glands of the tongue in a 55-year-old male. Histochemical and immunohistochemical stains are presented and include positivity for AE1/AE3 and p63, and negativity for progesterone receptor, androgen receptor, mammaglobin, S100 and BRAF V600E. PAS-D and Congo Red highlight special microamyloid spheroliths structures intraluminally.

CD1a is not effective in distinguishing calcifying epithelial odontogenic tumors from amyloid-rich central odontogenic fibroma.

OBJECTIVE: Differential diagnosis between the non-calcifying variant of calcifying epithelial odontogenic tumor (NCLC-CEOT) and amyloid-rich central odontogenic fibroma (AR-COdF) has become a debate, particularly regarding the frequency of CD1a positivity in both entities. This has led to the growing consensus that CD1a-positive staining in AR-NC lesions confirms the diagnosis of AR-COdF. Here, we assess the validity of this consensus. STUDY DESIGN: We collected the data of a case series of histopathologically distinct CEOTs, NCLC-CEOTs, and COdFs and stained them for CD1a and amyloid. Of the 9 CEOTs and NCLC-CEOTs, we diagnosed 4 as classic, 3 as associated with a dentigerous cyst, and 2 as combined CEOT/adenomatoid odontogenic tumors. Of the 9 COdFs, we diagnosed 3 as epithelial poor, 3 as epithelial rich (lacking amyloid), 2 as hyalinized with amyloid, and 1 as hyalinized without amyloid and assessed the staining results. RESULTS: Of the 9 CEOTs and NCLC-CEOTs, 7 stained positively for CD1a, 5 diffusely and 2 focally. Notably, 2 classic NCLC-CEOTs stained strongly CD1a positive. All 3 of the epithelial-poor COdFs were predictably CD1a negative. Of the 6 remaining COdFs, 2 were CD1a positive, 1 hyalinized-with-amyloid COdF diffusely and 1 epithelial-rich-without amyloid focally. CONCLUSIONS: CD1a positivity, which occurs in classic CEOT and NCLC-CEOT, does not help distinguish between NCLC-CEOT and AR-COdF and is inconsistent in all AR-COdFs. The diagnosis of CEOT and AR-COdF should be guided by appropriate histopathologic criteria irrespective of CD1a staining or the presence of amyloid or calcifications.

Modeling aging and retinal degeneration with mitochondrial DNA mutation burden.

Somatic mitochondrial DNA (mtDNA) mutation accumulation has been observed in individuals with retinal degenerative disorders. To study the effects of aging and mtDNA mutation accumulation in the retina, a Polymerase gamma (POLG) deficiency model, the POLGD257A mutator mice (PolgD257A), was used. POLG is an enzyme responsible for regulating mtDNA replication and repair. Retinas of young and older mice with this mutation were analyzed in vivo and ex vivo to provide new insights into the contribution of age-related mitochondrial dysfunction due to mtDNA damage. Optical coherence tomography (OCT) image analysis revealed a decrease in retinal and photoreceptor thickness starting at 6 months of age in mice with the POLGD257A mutation compared to wild-type (WT) mice. Electroretinography (ERG) testing showed a significant decrease in all recorded responses at 6 months of age. Sections labeled with markers of different types of retinal cells, including cones, rods, and bipolar cells, exhibited decreased labeling starting at 6 months. However, electron microscopy analysis revealed differences in retinal pigment epithelium (RPE) mitochondria morphology beginning at 3 months. Interestingly, there was no increase in oxidative stress observed in the retina or RPE of POLGD257A mice. Additionally, POLGD257A RPE exhibited an accelerated rate of autofluorescence cytoplasmic granule formation and accumulation. Mitochondrial markers displayed decreased abundance in protein lysates obtained from retina and RPE samples. These findings suggest that the accumulation of mitochondrial DNA mutations leads to impaired mitochondrial function and accelerated aging, resulting in retinal degeneration.

Intraoral salivary lymphoepithelial carcinoma: clinicopathologic and immunophenotypic characterization of 3 cases indicates elevated programmed death-ligand 1 expression.

OBJECTIVE: Intraoral salivary lymphoepithelial carcinoma (ISLEC) is a rare malignancy with programmed death-ligand 1 (PD-L1) expression levels that have been greatly understudied. We examined the clinicopathologic and immunophenotypic characteristics, including PD-L1 levels, of 3 cases of ISLEC. STUDY DESIGN: We searched the archives of 2 oral and maxillofacial pathology laboratories for specimens diagnosed as ISLEC between 1985 and 2022. We collected patient demographic and clinical data. Immunostaining for AE1/AE3, CK7, CD3, CD20, p16, p53, Ki67, and PD-L1 (SP263), as well as Epstein-Barr virus-encoded small RNAs (EBER) in situ hybridization (ISH) were performed. RESULTS: All 3 cases affected males aged 42 to 84 years (median = 61y) and involved the floor of the mouth, soft palate/uvula, and tongue. The lesions showed diffuse infiltration by non-keratinizing sheets and islands of undifferentiated carcinoma cells with associated dense lymphoplasmacytic inflammation. Immunohistochemically, all tumors showed AE1/AE3 positivity, selective p53 staining, and negativity for CK7 and p16. Ki67 highlighted 20%-80% of lesional cells. The inflammatory infiltrate comprised a mixed population of T and B lymphocytes. EBER ISH was positive in one case. All ISLECs displayed membranous, focal-to-diffuse, PD-L1 staining with tumor proportion score > 95% in two and 40-50% in the third case. CONCLUSIONS: The clinicopathologic and immunophenotypic characteristics of the cases we examined highlight the rarity of ISLEC and indicate overall high PD-L1 levels in this type of malignancy, rendering patients with ISLEC potential candidates for targeted α-PD-1/PD-L1 immunotherapy.

Mucoepidermoid carcinoma showing continuity with the surface mucosa of the oral cavity: a report of 14 cases.

OBJECTIVE: We aimed to characterize the histology and the clinicodemographic features of mucoepidermoid carcinoma (MEC), showing continuity with the oral surface mucosa. STUDY DESIGN: We reviewed 138 cases of intraoral MEC to identify cases that showed continuity with the surface mucosa and compared their clinicodemographic findings with those of MECs not showing continuity. We compared the sex ratio using the 2-sample Z-test and compared the age distribution using the 2-sample Kolmogorov-Smirnov test. RESULTS: Of the 138 cases examined, 14 showed continuity with the surface mucosa. Their histology showed surface mucosa with an apparent transition to an infiltrating tumor with mucous, intermediate, and epidermoid tumor cells growing in solid and cystic patterns. Their clinical appearance ranged from firm submucosal nodules to erythematous to ulcerated lesions. They showed a strong female predilection (6:1) and sharply bimodal age distribution, with sharp peaks in the fourth and seventh decades. CONCLUSIONS: Mucoepidermoid carcinomas that show continuity have a demographic pattern distinct from that of conventional MECs, showing a striking female predilection and bimodal age distribution and suggesting a difference in etiology. Pathologists should remain aware that MEC in the oral cavity can have a histologic appearance of surface origin to reach the correct diagnosis.

Atypical herpetic ulcerations in COVID-19 positive patients: A report of three cases.

Since the global COVID-19 pandemic, numerous reports have been made regarding oral lesions seen in COVID-19 patients. It remains unclear whether or not these are true manifestations of COVID-19. Here we present 3 patients who were hospitalized for COVID-19 and who developed atypical herpetic ulcerations during their treatment with remdesivir (Veklury) and steroids. In healthy patients, recurrent infection by herpes simplex virus (HSV) presents as lesions only on the lips and the attached oral mucosa. Atypical herpetic ulcerations are seen in immunocompromised patients. They present as large, stellate shaped ulcerations with raised borders and may involve movable mucosa. The 3 cases presented in this report resembled the atypical herpetic ulcerations typically seen in patients with immunosuppression. Through our report, we aimed to introduce the possibility of atypical herpetic ulcers in patients being treated for COVID-19, to allow for their timely diagnosis and to raise awareness of the underlying immunocompromised state.

Ectomesenchymal Chondromyxoid Tumor: A Neoplasm Characterized by Recurrent RREB1-MKL2 Fusions.

Ectomesenchymal chondromyxoid tumor is a rare and benign neoplasm with a predilection for the anterior dorsal tongue. Despite morphologic heterogeneity, most cases are characterized by a proliferation of bland spindle cells with a distinctive reticular growth pattern and myxoid stroma. The immunophenotype of these neoplasms is likewise variable; most cases express glial fibrillary acid protein and S100 protein, with inconsistent reports of keratin and myoid marker expression. The molecular pathogenesis is poorly understood; however, a subset of cases has been reported to harbor EWSR1 gene rearrangement. Following identification of an RREB1-MKL2 fusion gene by RNA Sequencing in an index patient, a retrospective review of additional cases of ectomesenchymal chondromyxoid tumors was performed to better characterize the clinical, immunohistochemical, and molecular attributes of this neoplasm. A total of 21 cases were included in this series. A marked predisposition for the dorsal tongue was confirmed. Most cases conformed to prior morphologic descriptions; however, hypercellularity, hyalinized stroma, and necrosis were rare attributes not previously emphasized. The neoplastic cells frequently coexpressed glial fibrillary acid protein, S100 protein, keratin, smooth muscle actin, and/or desmin; a single case was found to contain significant myogenin expression. An RREB1-MKL2 fusion product was identified in 19 tumors (90%), a single tumor (5%) had an EWSR1-CREM fusion product, and the remaining case lacked any known fusion gene by RNA Sequencing. The latter 2 cases subtly differed morphologically from many in the cohort. This series illustrates that recurrent RREB1-MKL2 fusions occur in most, perhaps all, cases of ectomesenchymal chondromyxoid tumor.

Assessment of biologically aggressive, recurrent glandular odontogenic cysts for mastermind-like 2 (MAML2) rearrangements: histopathologic and fluorescent in situ hybridization (FISH) findings in 11 cases.

BACKGROUND: Glandular odontogenic cyst (GOC) demonstrates a significant predilection toward localized biologic aggressiveness and recurrence. GOC shares certain histopathologic features with intraosseous mucoepidermoid carcinoma (IMEC). The current investigation evaluates a group of recurrent, biologically aggressive GOCs to determine whether any cases demonstrated unique histologic features or mastermind-like2 (MAML2) rearrangements common to IMEC. METHODS: Microscopic slides from 11 previously diagnosed GOCs were stained with hematoxylin and eosin and assessed by 2 study participants for 10 classic histopathologic features required to establish a diagnosis of GOC. Cases were evaluated utilizing break-apart fluorescent in situ hybridization (FISH) analysis for the presence of MAML2 gene rearrangements. Clinical and demographic data on all patients were recorded. RESULTS: The mean age for patients included in the study was 55.27 years with a range of 36 to 72 years. The most common presenting symptom was a jaw expansion, and all cysts presented initially as a unilocular or multilocular radiolucency. Cysts displayed a minimum of 6 of 10 histologic parameters necessary for a diagnosis of GOC. One case demonstrated MAML2 rearrangements by FISH. That case also showed marked ciliation of cyst-lining epithelial cells and extensive mucous-secreting goblet cell proliferation. CONCLUSION: Findings in the current study are in concert with previous investigations, and although this study finds only limited molecular evidence to support the premise that recurrent biologically aggressive GOCs are a precursor to IMEC, detection of MAML2 rearrangements in 1 case suggests that such a theoretic transition, while rare, is possible.

Oral Lymphomatoid papulosis type C: A diagnostic pitfall, often confused with T-cell lymphoma.

Eosinophilic ulcer of the oral mucosa (EUOM) is a rare, benign, self-resolving lymphoproliferative disorder, which typically presents with asymptomatic to mildly tender ulcers. Histological findings of EUOM are characterized by a polymorphic infiltrate with many eosinophils often extending into the underlying muscle. Although this entity is well documented within the dental literature, it is not well known to physicians. The pathogenesis of the condition is unclear, although reports dating back to 1997 suggest that at least a subset of EUOM represents CD30 positive lymphoproliferative disorder (CD30+ LPD). More specifically the original report and subsequent authors suggest that the patients fall on the spectrum of CD30+ LPD most reminiscent of Lymphomatoid papulosis (LyP) seen in the skin. This oral variant of LyP would be expected to have the same diverse morphologic spectrum as that seen in cutaneous LyP. We present five EUOM patients whose biopsies showed an atypical lymphocytic infiltrate most compatible with Type C LyP, a histologically unique subset of LyP, reminiscent of the biopsy findings encountered in the reported case by Ficarra and co-workers. (Ficarra, et al., 1997) In four of the five cases, the biopsies were interpreted by expert hematopathologists as an aggressive form of peripheral T cell lymphoma resulting in recommendations to administer systemic chemotherapy to four of the patients, the scheduling of one patient for induction therapy and transplantation before revision of the diagnosis, and administration of chemotherapy to one of the patients. The natural clinical course of spontaneous regression refuted the original diagnoses as a form of aggressive peripheral T cell lymphoma. Recognition of oral LyP is critical to avoid inadvertent exposure to potentially toxic chemotherapeutic regimens intended for the treatment of high grade lymphoma.

Histologic and immunohistochemical identification of cribriform adenocarcinoma.

OBJECTIVE: To assess whether tumors originally classified as adenocarcinoma not otherwise specified (Adca-NOS), adenoid cystic carcinoma (ACC), and polymorphous low-grade adenocarcinoma (PLGA) could be reclassified as cribriform adenocarcinoma of the tongue and minor salivary gland (CATMSG). STUDY DESIGN: Tumors diagnosed between 1992 and 2014 at Oral Pathology Laboratory, Inc. (New York Presbyterian Hospital) were selected. Each tumor was reviewed by 3 oral pathologists to confirm the diagnosis of CATMSG. After review, 11 of 70 Adca-NOS, 5 of 38 ACCs, and 5 of 23 PLGAs met the histologic criteria for CATMSG. One case diagnosed as CATMSG in 2014 was used as a control, and the following stains were completed: epithelial membrane antigen, Hector battifora mesothelial-1, p16, and CAM 5.2. Eleven Adca-NOS, 2 ACCs (tissue was available for only 2 of the 5 adenoid cystic carcinoma cases), and 5 PLGAs underwent immunohistochemical (IHC) staining. Positive HMBE-1, p16, and CAM 5.2 staining along with negative staining for epithelial membrane antigen were considered supportive of a diagnosis of CATMSG. RESULTS: Based on histologic features and IHC results, we were able to reclassify 10 tumors (8 Adca-NOS and 2 PLGA) as CATMSG. CONCLUSION: CATMSG should be distinguished from other salivary gland tumors with similar histologic features. The diagnosis of CATMSG can be made on hematoxylin and eosin staining alone, but IHC analysis can be useful for confirmation.

A subset of ectomesenchymal chondromyxoid tumours of the tongue show EWSR1 rearrangements and are genetically linked to soft tissue myoepithelial neoplasms: a study of 11 cases.

AIMS: Ectomesenchymal chondromyxoid tumour (ECT) is a rare, benign intraoral neoplasm showing a predilection for the anterior dorsum of the tongue. The World Health Organization includes ECT in the pathological spectrum of soft tissue myoepithelioma. EWS RNA-binding protein 1 gene (EWSR1) rearrangement is found in 45% of cutaneous, soft tissue and bone myoepithelial neoplasms, and pleomorphic adenoma gene 1 (PLAG1) aberrations are found in 37% of EWSR1-negative soft tissue myoepitheliomas. The aim of this study was to evaluate the presence of EWSR1 and PLAG1 rearrangements in ECTs. METHODS AND RESULTS: Eleven formalin-fixed, paraffin-embedded ECTs were evaluated with fluorescence in-situ hybridization probes for EWSR1 (22q12) and PLAG1 (8q12). Among the 11 ECTs tested, three (27.3%) showed EWSR1 rearrangement in >15% of tumour cells, whereas eight (72.7%) cases did not show EWSR1 rearrangement. Eight of nine (89%) ECTs showed gain of EWSR1, probably representing gain of all or part of chromosome 22, in a varying proportion of neoplastic cells ranging between 1.4% and 27.9%. PLAG1 rearrangement was not detected in the successfully hybridized tissue sections (7/11). No correlation was observed between the molecular and histopathological findings, such as morphology of the neoplastic cells, the presence of atypia, and matrical type. CONCLUSIONS: We identified EWSR1 rearrangement in >25% of ECTs. These results suggest that some ECTs are at least genetically related to myoepithelioma of the soft parts. Finally, PLAG1 aberrations do not appear to be critical in the pathogenesis of ECT of the tongue.

Epithelioid Multinodular Osteoblastoma of the Mandible: A Case Report and Review of Literature.

Epithelioid multinodular osteoblastoma is a rare variant of osteoblastoma characterized by numerous nodules of epithelioid osteoblasts surrounding bony trabeculae, as well as clusters of epithelioid osteoblasts without osteoid formation. It commonly occurs in the gnathic bones of the face and spine, and has a male predominance. To date, only 26 cases of epithelioid multinodular osteoblastoma have been reported and described in detail in the literature. Lucas et al. (Hum Pathol 25:117-134, 1994) described 43 cases of a variant of osteoblastoma that he termed epithelioid multifocal osteoblastoma. These both likely represent the same entity. Here, we report another case of this rare variant of osteoblastoma. An 18-year-old male patient presents with a periapical radiolucency in the region of vital tooth #30. The surgeon's differential diagnosis for this radiolucent lesion was ameloblastoma versus cyst. An incisional biopsy of the lesion revealed well-vascularized fibrous connective tissue containing a multinodular tumor composed of collections of epithelioid cells with osteoblastic differentiation surrounding zones of hyalinization and bony trabeculae. Multinucleated giant cells and rare typical mitotic figures were noted. Additionally present within the tumor were clusters of epithelioid osteoblasts without bony trabeculae. Residual immature viable bone trabeculae were noted surrounding the tumor. A diagnosis of epithelioid multinodular osteoblastoma was rendered. In this paper we present a rare case of epithelioid multinodular osteoblastoma of the mandible, provide a general review of the literature, and highlight the unique histological features that help differentiate this tumor from tumors classified as conventional osteoblastoma, aggressive osteoblastoma, pseudoanaplastic osteoblastoma and, most importantly, low-grade or osteoblastoma-like osteosarcoma.

Sebaceous carcinoma of the maxillary gingival: First reported case involving the gingiva.

Sebaceous carcinoma of the oral cavity is extremely rare. To date, only 9 cases of primary sebaceous carcinoma involving the oral cavity have been reported in the English literature, with the majority of cases occurring on the buccal mucosa. This report describes a case of sebaceous carcinoma involving the maxillary gingiva. To our knowledge this is the first reported case of sebaceous carcinoma of the gingiva.

Malignant rhabdoid tumor of the floor of mouth: first reported case in the oral cavity of an adult.

Malignant rhabdoid tumors (MRTs) are exceedingly rare lesions. To our knowledge, only 2 cases have been reported in the oral cavity, with both examples occurring in infants. The current case is the third reported case of MRT of the oral cavity and the first reported case to occur in an adult at this location. The following report describes the clinical, histologic and immunohistochemical features of this tumor.

Health, wellness and the allure of spices in the Middle Ages.

ETHNOPHARMOCOLOGICAL RELEVANCE: During the European Middle Ages aromatic products imported from Asia and Africa were credited with both preventive and curative medical properties. In addition spices provided an image of wellness and as they were expensive and had many uses in cuisine and fragrance, they functioned as prestige consumer goods. MATERIALS AND METHODS: This is an effort to look historically at a social and cultural phenomenon for the period roughly A.D. 1200-1500. Sources of information about the demand for and uses of spices include lists of materia medica, medical treatises, cookbooks, religious writings, descriptions of banquets and court ceremonial and literary works showing what might be called aspirational lifestyles. RESULTS: It is important to focus on the demand side of the spice trade rather than simply assuming a consistent demand and looking only at the supply (prices, routes, for example). CONCLUSIONS: The demand for spices must be understood in terms of their attributed medical and wellness powers, but these in turn are related to the mysterious Eastern origins of spices that enhanced their image as elite consumer products and their association with spiritual as well as medical healing.

Two cases of CD30+, anaplastic lymphoma kinase (ALK)-negative anaplastic large cell lymphoma with oral manifestations.

Anaplastic large cell lymphoma (ALCL), a subgroup of T-cell non-Hodgkin's lymphoma, is an uncommon tumor exhibiting CD30 positivity and a characteristic immunophenotypic profile. Histologically, ALCL is characterized by the proliferation of large, anaplastic lymphoid cells with eccentric horseshoe- or kidney-shaped nuclei and one or more prominent nucleoli. Rare cases have been cited in the literature of ALCL presenting primarily in the oral cavity. The purpose of this article was to present 2 instructive cases of CD30+, anaplastic lymphoma kinase-negative ALCL with oral and systemic involvement.