Single-cell and spatial profiling identify three response trajectories to pembrolizumab and radiation therapy in triple negative breast cancer

Strategies are needed to better identify patients that will benefit from immunotherapy alone or who may require additional therapies like chemotherapy or radiotherapy to overcome resistance. Here we employ single-cell transcriptomics and spatial proteomics to profile triple negative breast cancer biopsies taken at baseline, after one cycle of pembrolizumab, and after a second cycle of pembrolizumab given with radiotherapy. Non-responders lack immune infiltrate before and after therapy and exhibit minimal therapy-induced immune changes. Responding tumors form two groups that are distinguishable by a classifier prior to therapy, with one showing high major histocompatibility complex expression, evidence of tertiary lymphoid structures, and displaying anti-tumor immunity before treatment. The other responder group resembles non-responders at baseline and mounts a maximal immune response, characterized by cytotoxic T cell and antigen presenting myeloid cell interactions, only after combination therapy, which is mirrored in a murine model of triple negative breast cancer.

Primary Cutaneous Epithelioid Mesenchymal Tumor With a Novel ATP2B4::GLI1 Gene Fusion

ABSTRACT

GLI1 gene alterations (rearrangement or amplification) have been found in several bone and soft tissue tumors including pericytic tumors, gastric plexiform fibromyxoma, gastroblastoma, and a various group of epithelioid tumors with regional recurrence or distant metastasis. In this article, we describe a case of primary cutaneous epithelioid mesenchymal tumor harboring hitherto not reported ATP2B4::GLI1 gene fusion. A 42-year-old man presented with a growing firm lesion on the left postauricular scalp. Microscopically, the shave biopsy specimen revealed a dermal-based nodular proliferation of relatively monotonous epithelioid cells with round to ovoid nuclei and pale eosinophilic cytoplasm, accompanied by prominent stromal vasculature. Significant cytologic atypia, necrosis, and mitotic activity were absent. The tumor cells were partially positive for CD34 and S-100 protein, but were negative for other markers, including SOX-10, keratins, and myogenic markers. An ATP2B4::GLI1 gene fusion was identified by next-generation sequencing. Array CGH was also performed, but it did not show relevant chromosomal copy number changes. Awareness of this rare cutaneous tumor, and thus, reporting of additional cases is necessary for further delineating its full clinicopathologic spectrum.

A Rare Case of Diffuse-type Tenosynovial Giant Cell Tumor in a Teenager With Noonan Syndrome

Noonan syndrome is a common autosomal dominant disorder associated with an increased risk of malignancy. We report a 16-year-old female with Noonan syndrome (KRAS gene variant, Q22R) and diffuse-type tenosynovial giant cell tumor, a proliferative disorder that has been rarely reported in this population. These tumors may represent a complication of the dysregulated RAS/MAPK signaling pathway that underlies Noonan syndrome. They lack typical clinical features, causing misdiagnosis and delays in management, which could lead to osseous invasion requiring more complicated surgical procedures. Increased awareness of this association will improve the clinical outcomes of patients with Noonan syndrome who develop diffuse-type tenosynovial giant cell tumors.

Lack of PRAME Expression in Cutaneous T-Cell Lymphomas

Cutaneous T-cell lymphomas (CTCLs) are rare tumors with no established markers that can reliably distinguish between benign and malignant lesions. Preferentially Expressed Antigen in Melanoma (PRAME) is a cancer/testis antigen that is found in many solid and hematologic malignancies. PRAME overexpression typically portends a poor prognosis and lower chemotherapeutic response. To date, no studies have established a role for PRAME in CTCL. An analysis was performed on 47 cases definitively diagnosed as CTCL: 25 cases of mycosis fungoides, 2 of Sezary syndrome, 5 of CD30+ lymphoproliferative disorder, 7 of primary cutaneous anaplastic large T-cell lymphoma, 3 of primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder, 1 of subcutaneous panniculitis-like T-cell lymphoma, and 4 of angiocentric T-cell lymphoma. PRAME immunohistochemistry was completely negative in all cases. PRAME expression was not found in any CTCL subtypes, suggesting that the pathogenesis of CTCL is not mediated by PRAME. Further study is required to identify biomarkers that might aid in the diagnosis and prognostication of CTCLs.

Comparative Proteomic Analysis of HPV(+) Oropharyngeal Squamous Cell Carcinoma Recurrence

Deintensification therapy for human papillomavirus-related oropharyngeal squamous cell carcinoma (HPV(+) OPSCC) is under active investigation. An adaptive treatment approach based on molecular stratification could identify high-risk patients predisposed to recurrence and better select for appropriate treatment regimens. Collectively, 40 HPV(+) OPSCC FFPE samples (20 disease-free, 20 recurrent) were surveyed using mass spectrometry-based proteomic analysis via data-independent acquisition to obtain fold change and false discovery differences. Ten-year overall survival was 100.0 and 27.7% for HPV(+) disease-free and recurrent cohorts, respectively. Of 1414 quantified proteins, 77 demonstrated significant differential expression. Top enriched functional pathways included those involved in programmed cell death (73 proteins, p = 7.43 × 10^-30), apoptosis (73 proteins, p = 5.56 × 10^-9), β-catenin independent WNT signaling (47 proteins, p = 1.45 × 10^-15), and Rho GTPase signaling (69 proteins, p = 1.09 × 10^-5). PFN1 (p = 1.0 × 10^-3), RAD23B (p = 2.9 × 10^-4), LDHB (p = 1.0 × 10^-3), and HINT1 (p = 3.8 × 10^-3) pathways were significantly downregulated in the recurrent cohort. On functional validation via immunohistochemistry (IHC) staining, 46.9% (PFN1), 71.9% (RAD23B), 59.4% (LDHB), and 84.4% (HINT1) of cases were corroborated with mass spectrometry findings. Development of a multilateral molecular signature incorporating these targets may characterize high-risk disease, predict treatment response, and augment current management paradigms in head and neck cancer.

Acitretin-induced periungual pyogenic granulomas and review

Periungual pyogenic granulomas are benign vascular tumors that present as painful, round, spontaneously bleeding lesions composed of rapidly proliferating capillaries and excess tissue. The vast majority of pyogenic granulomas are caused by physical trauma or infectious agents and they may resolve spontaneously. Herein, we highlight a very rare case of periungual pyogenic granulomas induced by the regularly prescribed oral retinoid acitretin during treatment for congenital palmoplantar keratoderma. This unique case showed that it is feasible to continue acitretin therapy in the presence of pyogenic granuloma development if proper dose reduction and topical therapies are utilized. The patient's lesions resolved within two weeks of this protocol's initiation and the pyogenic granulomas did not recur over the course of a six-month follow-up observation period. In addition, we performed a systematic review of the literature using PubMed databases for the clinical features and treatments in other reported acitretin-induced pyogenic granuloma cases; we compiled a comprehensive list of other prescription drugs known to cause pyogenic granulomas up-to-date.

Hypofractionated radiation therapy and wound healing after massive sarcoma resection: Case report and review of the literature

Introduction

Large high-grade sarcomas are commonly managed with five weeks of pre-operative radiation with chemotherapy followed by surgical resection. Wound complications occur in about one out of three patients with this regimen. Hypofractionated radiation therapy (HFRT) is a developing pre-operative approach that delivers radiation over a shorter duration of 5–10 treatments.

Presentation of case

Two patients underwent HFRT with neoadjuvant chemotherapy followed by tumor resection. The first patient had high-grade de-differentiated liposarcoma, and the second patient a high-grade myxofibrosarcoma. Neither patient developed post-operative wound complications despite the massive tumor size.

Discussion

Less is understood regarding rates and risk factors associated with wound complications using this shortened radiation approach. With attention to surgical detail, and advancing radiation delivery technologies, rates of complications can be minimized.

Conclusion

We discuss our experience with a neoadjuvant hypofractionated chemoradiation protocol in two patients with large volume sarcomas resected from the chest wall and the thigh who did not develop acute wound complications. Further evaluation of this shortened regimen is warranted.

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Wound complications are common after sarcoma resection with preoperative radiation.

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Hypofractionated Radiation Therapy (HFRT) may be a safe alternative to conventional dose radiation.

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HFRT can be utilized with massive volume sarcomas safely.

Soft Tissue Special Issue: Selected Topics in the Pathology of Adipocytic Tumors

Our understanding of adipocytic tumors classification and diagnosis continues to evolve. We present a brief review and updated summary of selected adipocytic tumors involving the head and neck region. For the practicing pathologist, knowledge of these established and emerging entities is critical for the correct pathologic diagnosis and treatment of the patient.

Diagnostic utility of dual 5-hydroxymethylcytosine/Melan-A immunohistochemistry in differentiating nodal nevus from metastatic melanoma: An effective first-line test for the workup of sentinel lymph node specimen

BACKGROUND

Distinguishing benign nodal nevus from metastatic melanoma can be diagnostically challenging, with important clinical consequences. Recently, the loss of epigenetic marker, 5-hydroxymethylcytosine (5-hmC) expression by immunohistochemistry has been found in melanomas and atypical melanocytic neoplasms.

METHODS

About 41 metastatic melanomas and 20 nodal nevi were retrieved. Nuclear 5-hmC (brown) and cytoplasmic Melan-A Red (red) double immunohistochemical staining was performed.

RESULTS

Total or partial loss of nuclear expression of 5-hmC was noted in 40/41 metastatic melanomas; these tumor cells were strongly positive for Melan-A Red, except in one case of desmoplastic melanoma. All cases of nodal nevus showed uniformly retained nuclear expression of 5-hmC accompanied by strong Melan-A Red cytoplasmic staining. In two cases containing both nodal nevus and metastatic melanoma, all tumor cells were positive for Melan-A Red, but a nuclear expression of 5-hmC was selectively absent only in the melanoma tumor cells.

CONCLUSION

Dual 5-hmC/Melan-A Red immunohistochemistry is highly specific in distinguishing nodal nevus from metastatic melanoma. Our protocol for brown and red chromogens used in this study provides excellent color contrast and is easy to interpret. Furthermore, this dual staining method allows the preservation of limited tumor tissue, which could be used for potential molecular studies.

Cutaneous Malignant Vascular Neoplasms

Accurate diagnosis of cutaneous malignant vascular tumors, including angiosarcoma and epithelioid hemangioendothelioma, is critical for determination of appropriate clinical management and prognosis. Although there have been significant advances in understanding genetic aspects of cutaneous vascular biology, differential diagnosis of malignant vascular tumor involving skin and superficial soft tissue is a frequent source of difficulty. This brief overview highlights the clinicopathologic features of primary and secondary cutaneous angiosarcoma and epithelioid hemangioendothelioma and also provides a short summary of newer molecular data.

ETV6 rearrangement in a case of mammary analogue secretory carcinoma of the skin

Mammary analog secretory carcinoma of salivary glands is a relatively recently recognized entity that harbors the ETV6-NTRK3 fusion transcript. To date, only rare cases of mammary analog secretory carcinoma of the skin have been reported. A 57-year-old man presented with a 6.0 cm cystic mass in the axilla, involving the dermis and superficial subcutis. Microscopically, the tumor exhibited nodular aggregation of tubular and microcystic structures embedded in the dense fibrotic and hyalinized stroma. Characteristic 'colloid-like' eosinophilic secretory material was present within intraluminal spaces. Tumor cells were largely characterized by vesicular nuclei with inconspicuous nucleoli and pink vacuolated cytoplasm. With respect to immunohistochemistry, tumor cells were intensely positive for AE1/AE3, Cam 5.2, and CK7, whereas Ber-EP4 and CEA were completely negative. A dual color break-apart fluorescence in situ hybridization probe identified rearrangement of the ETV6 gene locus on chromosome 12. The patient is alive with no evidence of recurrent disease or metastasis 3 years after the initial surgery. In conclusion, we report a rare example of mammary analog secretory carcinoma of the skin with ETV6 rearrangement. Awareness of this unique cutaneous tumor and subsequent reporting of additional cases is necessary for better characterization of its completely clinicopathologic spectrum.

Malignant Melanoma of the Nail Apparatus

Background. Malignant melanoma of the nail apparatus is exceedingly rare. Increasingly, genetic studies have been employed to aid in distinguishing between malignant melanoma and benign melanocytic nevi. Methods. Archived nail apparatus melanomas were analyzed by fluorescence in situ hybridization (FISH) using probes targeting the genes at 6p25 (RREB1), 11q13 (CCND1), 8q24.1 (MYC), 6q23 (MYB), 9p21 (CDKN2A) and the centromeres of chromosomes 8 (D8Z2) and 6 (D6Z1). The results were correlated with clinical and demographic information. Results. Mean patient age was 57.8 years (range 23-92 years). In all, 5 of 7 (71%) cases involved the upper extremity digits. RREB1 gain was seen in all cases. CCND1 gain was seen in 6 of 7 (86%) cases, 3 of which were amplified. MYB loss and MYC gain were both seen in 5 of 7 (71%) cases. Homozygous loss of CDKN2A was not observed in any case. Two of 7 (28.6%) patients had lymph node metastasis and died of widely metastatic disease. These 2 patients harbored the most genetic aberrations: gains of RREB1, CCND1, and MYC, and MYB loss. Both benign melanocytic nevi controls showed normal FISH results. Conclusions. RREB1 and CCND1 gains are common in nail apparatus melanoma as in most melanomas, and an increased number of genetic aberrations may be associated with a poorer prognosis, though the limited number of cases precludes definitive correlation. FISH appears to be a useful adjunct in the diagnosis of nail apparatus melanomas and improves diagnostic confidence even in the setting of unambiguous histomorphology.

Radiation-induced pemphigus or pemphigoid disease in 3 patients with distinct underlying malignancies

The cutaneous lesions of radiation-induced pemphigus or pemphigoid disease may resemble other skin diseases, including recurrent underlying cancer. We performed a computerized search of Mayo Clinic (Rochester, Minnesota) archives and identified 3 cases of pemphigus or pemphigoid disease that occurred after radiation therapy for breast, cervical, and metastatic malignancies, respectively. In 2 of these patients, the disease was initially confined to the irradiated field but subsequently disseminated to other parts of the patients' bodies, including mucosal surfaces. In all 3 patients, the blistering disease occurred 5 to 14 months after the onset of radiation therapy. All 3 were treated with corticosteroids and demonstrated complete recovery of the skin eruption after radiotherapy was discontinued. Although the precise mechanism of this cutaneous eruption is unknown, clinicians should be alert for this potentially serious complication and evaluate all cutaneous eruptions developing during and after radiotherapy.

Malignant TFE3-rearranged perivascular epithelioid cell neoplasm (PEComa) presenting as a subcutaneous mass

Perivascular epithelioid cell neoplasms (PEComas) are a group of mesenchymal tumours with concurrent melanocytic and myogenic differentiation. Although many cases are sporadic, PEComas can be associated with tuberous sclerosis. A distinct subset of deep-seated PEComas has been shown to carry TFE3 fusions. To our knowledge, this is the first reported case of primary subcutaneous malignant PEComa with molecular confirmation of TFE3 gene rearrangement.

Pulp-dentin Regeneration

The goal of regenerative endodontics is to reinstate normal pulp function in necrotic and infected teeth that would result in reestablishment of protective functions, including innate pulp immunity, pulp repair through mineralization, and pulp sensibility. In the unique microenvironment of the dental pulp, the triad of tissue engineering would require infection control, biomaterials, and stem cells. Although revascularization is successful in resolving apical periodontitis, multiple studies suggest that it alone does not support pulp-dentin regeneration. More recently, cell-based approaches in endodontic regeneration based on pulpal mesenchymal stem cells (MSCs) have demonstrated promising results in terms of pulp-dentin regeneration in vivo through autologous transplantation. Although pulpal regeneration requires the cell-based approach, several challenges in clinical translation must be overcome—including aging-associated phenotypic changes in pulpal MSCs, availability of tissue sources, and safety and regulation involved with expansion of MSCs in laboratories. Allotransplantation of MSCs may alleviate some of these obstacles, although the long-term stability of MSCs and efficacy in pulp-dentin regeneration demand further investigation. For an alternative source of MSCs, our laboratory developed induced MSCs (iMSCs) from primary human keratinocytes through epithelial-mesenchymal transition by modulating the epithelial plasticity genes. Initially, we showed that overexpression of ΔN p63α, a major isoform of the p63 gene, led to epithelial-mesenchymal transition and acquisition of stem characteristics. More recently, iMSCs were generated by transient knockdown of all p63 isoforms through siRNA, further simplifying the protocol and resolving the potential safety issues of viral vectors. These cells may be useful for patients who lack tissue sources for endogenous MSCs. Further research will elucidate the level of potency of these iMSCs and assess their transdifferentiation capacities into functional odontoblasts when transplanted into the root canal microenvironment.

Cylindroma-like basaloid anal cancer presenting as a large pelvic mass in a patient with ulcerative colitis

Basaloid cancers of the lower gastrointestinal tract are rare. The lack of mucosal involvement of this type of tumor is uncharacteristic and, to our knowledge, has not been described. In addition, the cylindroma-like appearance of this cancer has only a few examples in the literature. A 51-year-old male presented to us with a history of ulcerative colitis (UC) and obstruction of the anal canal. Imaging and colonoscopy revealed an entirely extraluminal tumor. Percutaneous biopsy yielded a diagnosis of cylindroma-like basaloid carcinoma of the anal region. Neoadjuvant chemotherapy and radiation resulted in stable disease by RECIST criteria. Surgical planning ensued, which led to R0 resection of the tumor, total colectomy and end ileostomy for his UC, and reconstruction of the perineal defect with a rectus myocutaneous flap. Surveillance at 6 months demonstrated no evidence of disease.

WT1 expression in endocrine mucin-producing sweat gland carcinoma: a study of 13 cases

BACKGROUND

Endocrine mucin-producing sweat gland carcinoma (EMPSGC), a low-grade sweat gland carcinoma with a predilection for the eyelids, often shows areas of benign eccrine cysts, atypical intracystic proliferation and associated mucinous carcinoma, suggesting tumor progression. Wilms tumor 1 (WT1) protein, a transcription factor, is overexpressed in many tumors and plays a role in oncogenesis.

METHODS

A computer-based search for tumors diagnosed between 1989 and 2009 was conducted. Clinical data were obtained from pathology reports and patient records. Biopsies were reviewed for histologic features. Immunostaining was performed for WT1, chromogranin, synaptophysin, estrogen receptor (ER), epithelial membrane antigen (EMA), polyclonal carcinoembryonic antigen (P-CEA), cytokeratin 7 (CK7), cytokeratin 20 (CK20) and MIB-1.

RESULTS

Eight women and five men (mean age: 61.2 years; range: 40-77 years) presented with slow-growing eyelid nodules. Cases of EMPSGC were characterized by the presence of dermal nodules with various growth patterns. Adjacent eccrine cysts were present in five patients, atypical epithelial proliferation within the cyst wall in four patients, and an associated mucinous carcinoma in one patient. All tumors were positive for WT1, CK7, ER, P-CEA and EMA and negative for CK20. Tumors were positive for synaptophysin in 12 cases and chromogranin in nine cases. The MIB-1 proliferation index was low in most cases. No WT1 staining was observed in the overlying epidermis, adnexal structures or areas of benign eccrine cyst. WT1 expression was observed in areas of atypical epithelial proliferation, and the neoplastic cells.

CONCLUSIONS

The present study shows WT1 expression in the neoplastic epithelial cells of EMPSGC, areas of atypical intraductal proliferations, and mucinous carcinoma. The absence of WT1 expression in areas of benign eccrine cyst and cutaneous sweat glands suggests WT1 upregulation plays a role in tumor cell proliferation and progression of EMPSGC.

Angioleiomyoma of the upper extremity

PURPOSE

To determine the outcomes of surgical excision in the management of angioleiomyomas of the upper extremity.

METHODS

We retrospectively reviewed the medical records of 26 patients undergoing a surgical excision of an angioleiomyoma in the upper extremity between 1975 and 2012, who had at least 1 year of follow-up. There were 12 men and 14 women, with an average age of 55 ± 20 years. The most common location was the hand (n = 14). The onset of symptoms was on average 6 ± 5 years before presentation. The most common problem was a painful mass (19 of 26 patients). Average tumor size was 10 ± 7 mm.

RESULTS

Patients over the age of 60 years tended to have smaller tumors. There was no significant difference between average preoperative and postoperative grip strength in the affected and unaffected extremities. None of the lesions was diagnosed based on radiographic imaging. There was 1 postoperative complication. No recurrence was noted at an average 8.6-year follow-up (range, 1.0-21.0 y).

CONCLUSIONS

Angioleiomyomas present as a small, painful masses that can be reliably treated with marginal surgical excision.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Angiosarcoma in a patient with congenital nonhereditary lymphedema

Angiosarcoma is an uncommon but aggressive tumor of endothelial origin that may occur in the upper extremities of patients with postmastectomy lymphedema (Stewart-Treves syndrome) as well as in other regions. We present an unusual case of angiosarcoma associated with congenital nonhereditary lymphedema in an 18-year-old man. Our case underscores the need for a careful clinical examination and shows the importance of appropriate sampling and thorough pathologic examination of suspicious areas to exclude the presence of a malignant process.

Adjuvant hypofractionated intensity modulated radiation therapy after resection of regional lymph node metastases in patients with cutaneous malignant melanoma of the head and neck

PURPOSE

To evaluate outcomes in patients with malignant melanoma of the head and neck with resected regional lymph node (LN) metastases treated with adjuvant hypofractionated intensity modulated radiation therapy (IMRT).

METHODS AND MATERIALS

A retrospective review was performed of 46 patients with malignant melanoma of the head and neck with regional LN metastases treated with lymphadenectomy and adjuvant IMRT. Patients underwent neck dissection (n = 42) or local excision (n = 4) for regional metastases at initial diagnosis (n = 19) or recurrence (n = 27). Adjuvant IMRT was delivered twice per week over 2.5 weeks for a total dose of 30 Gray (Gy) in 5 fractions. Acute and late adverse events were recorded using the Common Toxicity Criteria for Adverse Events version 4. Site of first recurrence was defined as local-regional (LR, above the clavicles) or distant. Overall survival, disease-free survival, and disease recurrence risks were determined using Kaplan-Meier estimates.

RESULTS

The median follow-up in living patients was 2.8 years (range, 0.2-6.9). Most patients experienced acute grade 1-2 dermatitis (80%) and mucositis (85%). One patient (2%) experienced an acute grade 3 adverse event. Seven patients (16%) experienced late grade 2 adverse events. No patient experienced grade 3 or higher late adverse events. Site of first recurrence was LR alone (n = 5), both LR and distant (n = 1), and distant alone (n = 25). Five of the 6 LR recurrences were inside the IMRT planning target volume (PTV). In-PTV and total LR control at 3 years were 85% and 76%, respectively. Overall survival and disease-free survival at 3 years were 63% and 25%, respectively.

CONCLUSIONS

Adjuvant hypofractionated IMRT (30 Gy in 5 fractions) was associated with a high rate of in-PTV control and a low risk of serious adverse events.

Distinctive eosinophilic cytoplasmic inclusion bodies in melanocytic nevi: an immunohistochemical and ultrastructural study

BACKGROUND

We sought to further determine the histochemical, immunohistochemical and ultrastructural properties of eosinophilic cytoplasmic inclusion bodies in melanocytic nevi.

METHODS

Skin specimens from four patients with a known diagnosis of conventional melanocytic nevus (3) or Spitz nevus (1) and containing intracytoplasmic eosinophilic inclusion bodies were selected. In addition, melanomas (25), Spitz nevi (10) and blue nevi (4) were examined to determine the frequency of the inclusions.

RESULTS

Inclusions tended to be located in multinucleated melanocytes with abundant vacuolated cytoplasm. In conventional (hematoxylin and eosin-stained) sections, the degree of density and eosinophilia of intracytoplasmic inclusions varied with size. Periodic acid-Schiff, Fontana and Congo red stains showed no reactivity. All bodies were immunoreactive for ubiquitin but negative for tyrosinase, keratin and vimentin. Ultrastructurally, inclusion bodies were non-membrane bound, ranged from 4 to 7 µm, and were comprised of radiating filamentous structures with or without an electron-dense core. Electron probe x-ray microanalysis revealed no significant peaks. None of additional melanomas, Spitz nevi and blue nevi that were evaluated showed similar inclusions.

CONCLUSIONS

The inclusion bodies described herein bear no resemblance to other cytoplasmic inclusion bodies previously described in melanocytic lesions. There is no discernible relationship to melanosomes by ultrastructural analysis. We postulate a relationship with dysfunction of ubiquitin-mediated protein degradation occurring in melanocytes.