Primary alveolar soft tissue sarcoma of the central nervous system. Case report

Background: Alveolar soft part sarcoma (ASPS) is a rare, slow-growing soft tissue tumor with uncertain etiology; it is considered among the least common sarcomas, representing 0.2-1% of these cases in large studies. These tumors usually appear during childhood or young patients, with predominance in females. Case description: We introduce the case of ASPS in a 62-year-old man, who presented with 7 months of progressive headache and diplopia. The brain MRI showed an infiltrative lesion in the anterior fossa that extended to the right orbital roof. The possibility of metastasis was ruled out. The patient underwent resection of the tumor with posteriorly good visual and neurologic recovery. Histologic characterization demonstrated homogeneous eosinophilic cells with a solid, vascularized pattern, cells with large and binucleated nucleoli, and vessels with endothelial and myoepithelial hyperplasia; numerous apoptotic bodies and mitosis figures were also present, but no necrosis. On immunohistochemistry, cells exhibited positive CD56, NSE in membrane form, and slight myogenin; vessels were strongly positive for myogenin, myoglobin, CD34, CD31, factor VIII, vimentin, and nestin as well as for HBM45, CD20, GFAP, and S-100; cytokeratin showed fine extracellular and intracellular filaments; GATA and TTF1 were negative. Some clear cells were observed to be positive for CD68. The piece was diagnosed as a non-meningeal alveolar sarcoma of the soft tissue with solid pattern. Discussion and Conclusion: This case corresponds to the second tumor of this kind presented at our institution, the first one reported, and perhaps, one of the oldest patients to develop it worldwide.

A Multicenter Epidemiological Study on Second Malignancy in Non-Syndromic Pheochromocytoma/Paraganglioma Patients in Italy

No studies have carried out an extensive analysis of the possible association between non-syndromic pheochromocytomas and paragangliomas (PPGLs) and other malignancies. To assess the risk of additional malignancy in PPGL, we retrospectively evaluated 741 patients with PPGLs followed-up in twelve referral centers in Italy. Incidence of second malignant tumors was compared between this cohort and Italian patients with two subsequent malignancies. Among our patients, 95 (12.8%) developed a second malignant tumor, which were mainly prostate, colorectal and lung/bronchial cancers in males, breast cancer, differentiated thyroid cancer and melanoma in females. The standardized incidence ratio was 9.59 (95% CI 5.46–15.71) in males and 13.21 (95% CI 7.52–21.63) in females. At multivariable analysis, the risk of developing a second malignant tumor increased with age at diagnosis (HR 2.50, 95% CI 1.15–5.44, p = 0.021 for 50–59 vs. <50-year category; HR 3.46, 95% CI 1.67–7.15, p < 0.001 for >60- vs. <50-year). In patients with available genetic evaluation, a positive genetic test was inversely associated with the risk of developing a second tumor (HR 0.25, 95% CI 0.10–0.63, p = 0.003). In conclusion, PPGLs patients have higher incidence of additional malignant tumors compared to the general population who had a first malignancy, which could have an impact on the surveillance strategy.

IMMU-27. LONG TERM STABILIZATION OF RECURRENT HIGH-GRADE GLIOMA WITH PD-1 INHIBITOR PEMBROLIZUMAB IN TWO CASES

INTRODUCTION Despite PD-1 inhibition having success in many cancers, it has uncertain effects in brain tumors. We report two cases of recurrent high-grade gliomas that have remained stable for over one year since starting pembrolizumab. CASE REPORTS Case 1: A 59-year-old male was diagnosed with glioblastoma (GBM) without MGMT methylation or IDH mutation in late 2018 after surgery. He received radiation and temozolomide (TMZ) followed by adjuvant TMZ before tumor progression. He underwent second tumor debulking with recurrent GBM on pathology with negative PD-L1 expression. He started carboplatin. Progression was noticed after 7 to 8 cycles. Pembrolizumab was added. Tumor was stabilized. Carboplatin was completed after total 12 cycles and the patient has continued single agent of pembrolizumab for more than one year with stable brain MRIs. The patient has survived for 24 months since recurrence and 30 months since diagnosis. Case 2: A 53-year-old male had a brain tumor discovered on MRI in 2012 and received no treatment until resection in 2014. In 2016, he underwent second tumor debulking and was diagnosed with anaplastic oligodendroglioma with negative PD-L1 expression. He received radiation followed by PCV regimen. 17 months since diagnosis, he had first tumor progression on PCV. TMZ was started. 22 months since diagnosis, bevacizumab was initiated due to further growth. 33 months since diagnosis, pembrolizumab was added due to new lesions after 12-months of bevacizumab therapy. His tumor was stabilized. Bevacizumab was eventually discontinued. He has continued single agent pembrolizumab for 6 months so far. His tumor has been stable for 22 months since starting pembrolizumab. Survival has been 38 months from first recurrence and 7 years since tissue diagnosis. DISCUSSION These cases demonstrate the potential effects of anti-PD-1 immunotherapy in stabilizing recurrent high-grade glioma with combination of other treatment agents followed by single agent as maintenance therapy.

Primary Biphasic Hepatic Sarcoma in DICER1 Syndrome

DICER1 tumor predisposition syndrome is a rare genetic disorder that predisposes individuals to multiple benign and malignant neoplasms. The phenotype is vast and includes pleuropulmonary blastoma (PPB), thyroid nodules, cystic nephroma, Wilms tumor, ovarian Sertoli–Leydig cell tumor, and medulloepithelioma, among others. Herein, we describe a patient with a DICER1 germline pathogenic variant presenting with two neoplasms that are not commonly encountered in the context of DICER1 syndrome. The first tumor is a multiloculated cystic hepatic lesion with a biphasic pattern, composed of cysts lined by bland biliary type (CK19-positive) epithelium surrounded by a condensation of sarcomatous spindled cell proliferation in a myxoid stroma. This neoplasm resembled PPB or cystic nephroma with malignant transformation. The second tumor is a chest nodule consistent with low-grade hidradenocarcinoma. Although it is difficult to speculate with just a single case, these unusual neoplasms occurring in particular at a young age raises the possibility that they can be inherent to, and thus, be part of the DICER1 tumor predisposition syndrome phenotype.

Dissecting the NK Cell Population in Hematological Cancers Confirms the Presence of Tumor Cells and Their Impact on NK Population Function

The lymphocyte lineage natural killer (NK) cell is part of the innate immune system and protects against pathogens and tumor cells. NK cells are the main cell effectors of the monoclonal antibodies (mAbs) that mediates antibody-dependent cell cytotoxicity (ADCC). Hence, it is relevant to understand NK physiology and status to investigate the biological effect of mAbs in the clinic. NK cells are heterogeneous with multiple subsets that may have specific activity against different attacks. The presence of viral-sculpted NK cell populations has already been described, but the presence of cancer-sculpted NK cells remains unknown. Cancer induces a broad NK cell dysfunction, which has not been linked to a specific population. Here, we investigated the NK cell population by Uniform Manifold Approximation and Projection (UMAP) embed maps in Hodgkin lymphoma (HL) and acute myeloid leukemia (AML) patients at diagnosis and at least 30 days after treatment, which correlates with tumor cell clearance. We found that the NK lineage largely responded to the tumor by generating antitumor NK cells and renewing the population with a subset of immature NK cells. However, we failed to identify a specific “memory-like” subset with the NK cell markers used. Moreover, in patients in relapse, we found essentially the same NK populations as those found at diagnosis, suggesting that NK cells equally respond to the first or second tumor rise. Finally, we observed that previous cytomegalovirus (CMV) infection largely affects the tumor-associated changes in NK population, but the CMV-associated CD57+NKG2C+ NK cell population does not appear to play any role in tumor immunity.

Dissecting the NK Cell Population in Hematological Cancers Confirms the Presence of Tumor Cells and their Impact on NK Population Function

Natural killer (NK) cells are part of the innate immune system, protects against pathogens and tumor cells and are the main cell effectors of monoclonal antibodies (mAbs) generating antibody-dependent cell cytotoxicity (ADCC). Hence it is relevant to understand NK physiology and status to investigate the biological effect of mAbs in the clinic. The presence of viral-sculpted NK cell populations has already been described, but the presence of cancer-sculpted NK remains unknown. Cancer induces a broad NK cell dysfunction. We investigated the NK cell population by Uniform Manifold Approximation and Projection (UMAP) embed maps in Hodgkin lymphoma (HL) and acute myeloid leukemia (AML) patients at diagnosis and at least 30 days after treatment, which correlates with tumor cell clearance. The NK lineage largely responded to the tumor by generating antitumor NK cells and renewing the population with a subset of immature NK cells. However, we failed to identify specific &ldquo;memory-like&rdquo; subsets. Moreover, in patients in relapse we found essentially the same NK populations that at diagnostic, suggesting that NK cells equally respond to the first or second tumor rise. Finally, previous CMV infection largely affects tumor-associated changes in NK population, but the CMV-associated CD57+NKG2C+ NKs do not appear to play any role in tumor immunity.