Comparison of 2 T-Cell Receptor-γ Clonality Assays on Skin Biopsies Suspicious for Mycosis Fungoides

ABSTRACT

PCR-based fragment analysis of the T-cell receptor (TCR) gene is used extensively in diagnostic labs to assess clonality in T-cell populations in multiple tissue sites. Of the numerous TCR assays that have been reported, studies assessing use on biopsies suspicious for mycosis fungoides specifically are lacking. We compared clonality findings from a previously run 2-tube/2-fluorochrome dye assay to a redesigned 1-tube/1-fluorochrome dye assay on formalin-fixed skin biopsies. Overall, the accuracy of the 2-tube assay was marginally better (75.7% vs. 71.4%), when using clinical history combined with histologic diagnosis as the gold standard. The 2-tube assay had better sensitivity (73.7% vs. 65.8%), while the 1-tube assay had superior specificity (93.8% vs. 87.5%). Clonality results were easier to interpret with the 1-tube assay. In nearly 19% of cases, a change of assays on the same biopsy resulted in a change of clonality interpretation. For laboratories that change TCR-γ clonality assays, follow-up biopsies for mycosis fungoides assessment may result in a change of diagnosis.

Cutaneous mucormycosis involving a colostomy site

Cutaneous mucormycosis is a rapidly advancing fungal infection that most commonly occurs due to airborne spread or direct inoculation and requires early detection and prompt treatment for optimal survival. Major risk factors include diabetes, transplantations, malignancies, surgical procedures, and HIV. Diagnostic criteria are based on microscopy and culture. We present an immunocompromised patient with cutaneous mucormycosis that developed in a peristomal ulcer following a hemicolectomy procedure. Histopathologic evaluation was indicative of mucormycosis. Intravenous posaconazole treatment was initiated, but unfortunately, the patient's condition deteriorated and he passed away.

Abstract A40: Evaluation of the tumor microenvironment in mycosis fungoides using the PanCancer IO 360™ assay and nCounter® platform

BACKGROUND: Alterations in the tumor microenvironment (TME) can result in a “T-cell inflamed” TME, which is characterized by activation of the PD1/PD-L1 pathway, immunosuppression, and production of anergic, “exhausted” CD8(+)-T-cells. Similar alterations in the TME of Mycosis Fungoides (MF) have been linked to disease progression. However, the relationship between progression and the TME in MF remains incompletely understood. We aimed to further study the TME in MF using the PanCancer IO 360™ 750-gene expression panel and nCounter® platform (Nanostring; Seattle, WA). DESIGN: Clinical and laboratory data from the electronic medical record were reviewed in combination with microscopic review of biopsies from 27 patients to confirm diagnosis of MF and assign samples as “low-grade” (patch/plaque; n=8) or “high-grade” (tumor/large cell transformation, n=19). Patients were also classified as having “limited stage” (TNMB1 <1B, n=8) or “advanced stage” (TNMB1 >1B, n=19) disease. All patients received prior, heterogenous treatment, but no patients received prior anti-PD1 therapy. RNA was extracted from formalin-fixed, paraffin-embedded (FFPE), punch biopsy sections and analyzed per manufacturer’s instructions. Gene expression scores (log2) and a “tissue inflammation score” (TIS) were calculated for each sample. A TIS of >5 has been associated with the presence of a “T-cell inflamed” microenvironment. Samples scores were compared by histologic group and disease stage as described above. RESULTS: Twenty-nine of 30 samples had sufficient RNA integrity for analysis. TIS was >5 in 26/30 samples (median, 7.6; range, 4.3-9.3). No significant differences in TIS were identified between low-grade/limited-stage and high-grade/advanced-stage samples. High-grade samples had significantly increased expression of PD1 and higher amounts of exhausted CD8(+)-cells than low-grade samples (p= 0.015, 0.027). Low-grade samples showed significantly higher expression of ARG1, B7-H3, and genes associated with tissue hypoxia. Expression of genes associated with tumor proliferation was higher in high-grade lesions (p= 0.0019). Limited stage samples showed higher levels of endothelial cells, mast cells, and T-regulatory cells (p=0.033, 0.024, 0.004,) than advanced stage samples. Proliferation, PD1, and exhausted CD8 scores trended higher in advanced stage disease but did not reach statistical significance. CONCLUSION: Our findings indicate that the IO 360™ panel provides comprehensive analysis of the TME in MF. Most samples showed a TIS of >5, suggesting a T-cell inflamed TME in MF. Increased PD1 and exhausted CD8(+) cells were found in high-grade lesions, supporting a role for this pathway in progression. Increased expression of factors associated with angiogenesis (endothelial cells, ARG1) and immunosuppression (B7-H3, tissue hypoxia, mast cells, T-regulatory cells) suggest these mechanisms may play a role in early stages of disease. These findings highlight the complex and dynamic nature of the TME during MF progression, and the need for further study.

Citation Format: Stanton Miller, Akshat Patel, Kiran A Kumar, Farrukh Awan, Heather W Goff, Travis Vandergriff, Marisa Juntilla, Franklin Fuda, Weina Chen, Jesse M Jaso. Evaluation of the tumor microenvironment in mycosis fungoides using the PanCancer IO 360™ assay and nCounter® platform [abstract]. In: Proceedings of the Third AACR International Meeting: Advances in Malignant Lymphoma: Maximizing the Basic-Translational Interface for Clinical Application; 2022 Jun 23-26; Boston, MA. Philadelphia (PA): AACR; Blood Cancer Discov 2022;3(5_Suppl):Abstract nr A40.

A severe presentation of acute generalized exanthematous pustulosis with non-infectious circulatory shock in an adolescent

We present a severe case of acute generalized exanthematous pustulosis (AGEP) secondary to trimethoprim-sulfamethoxazole complicated by non-infectious circulatory shock in a 16-year-old boy. Hemodynamic instability has been reported as a complication of AGEP in adults, but is rarely observed in pediatric patients. The patient we present demonstrated characteristic cutaneous findings of AGEP including isolated non-follicular, sterile pustules on a background of erythema with involvement at intertriginous areas and subsequently developed non-infectious circulatory shock. This case expands the spectrum of possible clinical presentations for AGEP in pediatric patients.

Pink nodule of the chin: an unusual presentation of metastatic carcinoma

Renal cell carcinoma (RCC) is the most lethal urological tumor, often because it is widely metastasized at the time of diagnosis. There are reports of cutaneous metastases, most commonly to the head and neck, presenting late after RCC is diagnosed. This case presentation explores a 45-year old female patient with a growing skin lesion on her chin, previously treated as an epidermoid cyst before presenting to dermatology clinic. We present a case of cutaneous metastatic clear cell renal cell carcinoma presenting 7 years after initial diagnosis.

Ichthyosiform sarcoidosis: Report of a case and comprehensive review of the literature

Sarcoidosis is a disease that can affect a multitude of organs and manifest as cutaneous disease. Cutaneous manifestations of sarcoidosis vary widely in morphology, earning the nickname of "great imitator," and the diagnosis often requires clinicopathologic correlation and additional laboratory and radiographic workup. We present the case of a 42-year-old African American woman with ichthyosiform sarcoidosis on the bilateral lower extremities. As one of the rarest specific variants of cutaneous sarcoidosis, ichthyosiform is understudied and has been primarily documented in case reports and series. We undertake a comprehensive review of the literature to identify key clinicopathologic features including the characterization of sites of cutaneous and systemic involvement, as well as typical histopathological findings. Lower extremities were the most involved body site (85.7%). Extracutaneous organ involvement centered around pulmonary (65.7%), lymph node (57.1%), and ocular (31.4%) involvement. Of the histopathological features reported, hyperkeratosis (51.4%) and diminished stratum granulosum (62.9%) were most frequently reported in conjunction with dermal granulomas (100%). We hope that these findings will serve to aid clinicopathological correlation and accurate diagnosis of ichthyosiform sarcoidosis.

A lobulated mass on the upper back with prominent vasculature: A giant basal cell carcinoma

Basal cell carcinoma (BCC) is characterized by slow but locally invasive growth. Although there is low metastatic potential, if not treated early, these skin cancers can lead to significant morbidity and mortality. In this case report, we present a man with a neglected BCC that developed into what is termed a giant BCC or one that is greater than 5 cm. This tumor was discovered only upon workup of orthostatic lightheadedness and iron deficiency anemia. Although rare, basal cell carcinoma must be included on the differential of a large cutaneous lesion and may be a source of significant blood loss.

Assessing comfort level with pediatric skin specimens among dermatopathologists and pediatric pathologists: A national cross-sectional survey

BACKGROUND

Cutaneous histopathologic diagnoses in children often differ from those in adults. Depending on practice setting, these specimens may be evaluated by dermatopathologists or pediatric pathologists. We sought to determine whether comfort level with pediatric dermatopathology is associated with prior training, pediatric dermatopathology exposure during fellowship, career duration, or specimen subtype.

METHODS

We surveyed dermatopathologists and pediatric pathologists practicing in the United States. Training and practice variables were evaluated by multivariable regression for association with comfort level.

RESULTS

Of the 156 respondents, 72% were dermatopathologists (response rate 11.6%) and 28% were pediatric pathologists (response rate 9.3%). Dermatopathologists reported higher comfort overall (P < .001); this was also true for inflammatory dermatoses and melanocytic neoplasms (P < .001). Thirty-four percent and 75% of dermatopathologists and pediatric pathologists, respectively, reported lower comfort with pediatric skin specimens than their usual cases. Pediatric pathologists were 28% more likely to refer these cases to colleagues. Among dermatopathologists, dermatology-trained were more comfortable than pathology-trained colleagues interpreting inflammatory dermatoses (P < .001).

CONCLUSIONS

Pathologists' comfort with pediatric dermatopathology varied significantly based upon prior training, career duration, and specimen subtype. These results suggest opportunities for improving education in this domain.

Blastic plasmacytoid dendritic cell neoplasm in a young patient

Blastic plasmacytoid dendritic cell neoplasm is a rare hematologic neoplasm originating from plasmacytoid dendritic cell precursors that has an aggressive disease course with typically poor prognosis. Herein, we report a man in his early twenties who presented with rapid onset of violaceous nodules and purpuric papules and macules that began on his chest before spreading to his arms, back, face, scalp, and legs. He also exhibited systemic symptoms including weight loss and night sweats. He was diagnosed with blastic plasmacytoid dendritic cell neoplasm and began treatment with aggressive multidrug therapy. Thus far his treatment has resulted in complete resolution of his cutaneous manifestations.

Chondrodermatitis nodularis nasi

Chondrodermatitis nodularis helicis is a relatively common ulcerative, inflammatory condition affecting the skin, and cartilage of the ear. We present a case of chondrodermatitis affecting the skin and cartilage of the nose, designated chondrodermatitis nodularis nasi. Clinically, chondrodermatitis presents as a singular, painful, ulcerated papule or nodule that results from prolonged pressure, trauma, sun exposure, or vascular compromise. The clinical features resemble those seen in skin cancer, and a biopsy is often required to secure the diagnosis. Histopathologic analysis of chondrodermatitis demonstrates a central ulcer, beneath which there is fibrinoid necrosis of the dermis and inflammatory infiltrates. The ulcer is bordered by pseudoepitheliomatous hyperplasia with underlying granulation tissue. In addition to a clinical and morphologic description of chondrodermatitis nodularis nasi, a discussion of etiological factors and differential diagnoses is included. Increased recognition and reporting of the condition will allow for the exploration of optimal treatment strategies.

Pigmented fungiform papillae of the tongue: a clinical and histologic description

A 28-year-old man with a history of mycosis fungoides presented for evaluation of multiple dark-brown macules and hyperpigmented dome-shaped papules on the distal tongue. A shave biopsy of the tongue revealed melanin pigment in the basal keratinocytes and melanophages in the lamina propria, consistent with pigmented fungiform papillae of the tongue. Relevant clinical and histologic features of this diagnosis are reviewed.

Refractory macrophage activation syndrome in the setting of adult-onset Still disease with hemophagocytic lymphohistiocytosis detected on skin biopsy treated with canakinumab and tacrolimus

A 19-year-old Caucasian female with adult-onset Still disease (AOSD) presented for evaluation of an acute clinical decompensation and atypical annular papules and plaques with purpura on the lower extremities. A punch biopsy demonstrated histiocytes with engulfed degenerated erythrocytes and lymphocytes, consistent with hemophagocytic lymphohistiocytosis (HLH). HLH, clinically referred to as macrophage activation syndrome, is a rare complication of AOSD and is life-threatening. Relevant clinical, laboratory, and histologic features of this diagnosis are reviewed.