Intraosseous inflammatory myofibroblastic tumor of the mandible with a novel ATIC-ALK fusion mutation: a case report

Case report: ATIC-ALK fusion in infant-type hemispheric glioma and response to lorlatinib

Introduction

Infant type hemispheric gliomas are a rare tumor with unique molecular characteristics. In many cases these harbor mutations in receptor tyrosine kinase pathways and respond to targeted therapy. Here we describe the case of an infant with this type of tumor with a novel ATIC-ALK fusion that has responded dramatically to the ALK inhibitor lorlatinib, despite being refractory to standard chemotherapy.

Case description

The infant was initially treated with standard chemotherapy and found to have an ATIC-ALK fusion. When surveillance imaging revealed progressive disease, the patient was switched to the ALK-inhibitor lorlatinib at 47 mg/m²/day. The patient demonstrated a significant clinical and radiographic response to the ALK inhibitor lorlatinib after just 3 months of treatment and a near complete response by 6 months of therapy.

Conclusion

The ALK inhibitor lorlatinib is an effective targeted therapy in infant type hemispheric glioma patients harboring ATIC-ALK fusion.

Plasma cells in oral lesion: A clue to diagnosis or a diagnostic dilemma

Objective

Plasma cells can just represent a part of host inflammatory response or form the cornerstone of diagnosis such as IgG4-related disease (IgG4RD) and plasma cell dyscrasias and sometimes create a diagnostic dilemma. The study aims to discuss a series of plasma cell lesions which we encountered in the oral cavity, discuss the diagnostic conundrum of plasma cell lesions. We also propose a working classification for their interpretation.

Materials and Methods

All plasma cell lesions affecting the oral and maxillofacial region were retrieved from the archives of the Department of Oral and Maxillofacial Pathology. The cases were analyzed on the basis of histomorphology and immunohistochemical markers along with clinical, imaging and laboratory findings.

Results

Thirteen (0.64%) of 2026 oral lesions were diagnosed with plasma cell lesions. Out of 13 cases, 9 were plasma cell gingivitis, 2 IgG4-RD, 1 plasma cell myeloma and 1 plasmablastic lymphoma. Representative case from each category is discussed along with one case of well-differentiated squamous cell carcinoma (WDSCC) masquerading as plasma cell dyscrasias.

Conclusion

We discuss the practical difficulties faced during the diagnosis of these oral plasma cell entities along with a working classification and propose an efficient diagnostic scheme for the correct characterization of these lesions.

Case Report: Efficacy of ensartinib treatment in pulmonary inflammatory myofibroblastic tumor with a rare GCC2-ALK fusion

Background

Inflammatory myofibroblastic tumors (IMTs) are rare with distal metastasis. Approximately 50% of patients have anaplastic lymphoma kinase (ALK) fusion. Patients with non-small cell lung cancer with ALK fusion are usually highly sensitive to ALK tyrosine kinase inhibitors (TKIs), but the application of TKI in IMT needs further exploration.

Case presentation

A 66-year-old man was diagnosed with IMT with bone metastasis, cT4N0M1c, IVB stage. Immunohistochemistry results showed that he was ALK positive, and next-generation sequencing revealed GCC2-ALK fusion in the IMT. The patient was administered first-line ensartinib 225-mg QD, which targeted GCC2-ALK fusion, and denosumab 120-mg Q4w anti-bone metastasis therapy. The patient developed a grade III rash, and the ensartinib dose was reduced to 125 mg QD; consequently, he achieved a partial response (PR), and the side effects significantly reduced. Computed tomography results showed that the patient maintained PR after 7 months of follow-up, and he was still in a state of progression-free survival without obvious side effects after 11 months of follow-up.

Conclusion

To our knowledge, this is the first case of the GCC2-ALK fusion type in IMT and the first report showing that the use of ensartinib as a TKI in IMT has clinical benefits.

A clinical signature predicting the malignant transformation of inflammatory myofibroblastic tumor in the head and neck

BACKGROUND

Inflammatory myofibroblastic tumors in the head and neck (HNIMTs) sometimes show aggressive clinical features and can be diagnosed as HNIMT with malignant transformation.

METHODS

The clinicopathological features of 45 HNIMTs with or without malignant transformation were retrospectively investigated. Logistic regression and receiver operating characteristic analysis were used to establish the predictive model.

RESULTS

HNIMT with malignant transformation was associated with worse prognosis. HNIMT with a tumor size of >4.4 cm, tumors located in the maxillary sinus, or a preoperative neutrophil-to-lymphocyte ratio (NLR) greater than 1.958 were associated with higher chance of malignant transformation, with an AUC value of 0.9189. Postoperative radiotherapy could benefit HNIMT patients with high risk of malignant transformation.

CONCLUSIONS

HNIMT patients with a tumor size of >4.4 cm, tumors located in the maxillary sinus, and a preoperative NLR over 1.958 were associated with a higher risk of malignant transformation. These patients can benefit from postoperative radiotherapy.

Comprehensive Molecular Analysis of Inflammatory Myofibroblastic Tumors Reveals Diverse Genomic Landscape and Potential Predictive Markers for Response to Crizotinib

PURPOSE

The European Organization for Research and Treatment of Cancer (EORTC) clinical phase II trial 90101 "CREATE" showed high antitumor activity of crizotinib, an inhibitor of anaplastic lymphoma kinase (ALK)/ROS1, in patients with advanced inflammatory myofibroblastic tumor (IMFT). However, recent findings suggested that other molecular targets in addition to ALK/ROS1 might also contribute to the sensitivity of this kinase inhibitor. We therefore performed an in-depth molecular characterization of archival IMFT tissue, collected from patients enrolled in this trial, with the aim to identify other molecular alterations that could play a role in the response to crizotinib.

EXPERIMENTAL DESIGN

Twenty-four archival IMFT samples were used for histopathological assessment and DNA/RNA evaluation to identify gene fusions, copy-number alterations (CNA), and mutations in the tumor tissue. Results were correlated with clinical parameters to assess a potential association between molecular findings and clinical outcomes.

RESULTS

We found 12 ALK fusions with 11 different partners in ALK-positive IMFT cases by Archer analysis whereas we did not identify any ROS1-rearranged tumor. One ALK-negative patient responding to crizotinib was found to have an ETV6-NTRK fusion in the tumor specimen. The CNA profile and mutational landscape of IMFT revealed extensive molecular heterogeneity. Loss of chromosome 19 (25% of cases) and PIK3CA mutations (9% of cases) were associated with shorter progression-free survival in patients receiving crizotinib.

CONCLUSIONS

We identified multiple genetic alterations in archival IMFT material and provide further insight into the molecular profile of this ultra-rare, heterogeneous malignancy, which may potentially translate into novel treatment approaches for this orphan disease.

Novel fusion sarcomas including targetable NTRK and ALK

BACKGROUND

Challenging emerging entities with distinctive molecular signatures may benefit from algorithms for diagnostic work-up.

METHODS

Fusion sarcomas (2020-2021, during pandemic) were diagnosed by clinicoradiology, morphology, phenotype, and next-generation sequencing (NGS).

RESULTS

Six fusion sarcomas in two males and four females involved the chest-wall, neck, or extremities; ages ranged 2-73, median 18 years. Sizes ranged 5.3-25.0, median 9.1 cm. These include high grade 1) TPR-NTRK1 of proximal femur with a larger rounded soft tissue mass, previously considered osteosarcoma yet without convincing tumor matrix. A pathologic fracture necessitated emergency hemipelvectomy (NED) and 2) novel KANK1-NTRK2 sarcoma of bone and soft tissue with spindled pleomorphic to epithelioid features (AWD metastases). 3) Novel ERC1-ALK unaligned fusion, a low grade infiltrative deep soft tissue hand sarcoma with prominent-vascularity, myopericytoid/lipofibromatosis-like ovoid cells, and collagenized stroma, was successfully treated with ALK-inhibitor (Crizotinib), avoiding amputation. These NTRK and ALK tumors variably express S100 and CD34 and were negative for SOX10. 4) and 5) CIC-DUX4 round cell tumors (rapid metastases/demise), one with COVID superinfection, were previously treated as Ewing sarcoma. These demonstrated mild pleomorphism and necrosis, variable myxoid change and CD99 reactivity, and a distinctive dot-like-Golgi WT1 immunostaining pattern. 6) A chest wall/thoracic round cell sarcoma, focal CD34/ keratins/CK7, revealed nuclear-STAT6, STAT6-NAB2 by NGS, confirming malignant solitary fibrous tumor, intermediate-risk-stratification (AWD metastases).

CONCLUSIONS

Recent fusion sarcomas include new KANK1-NTRK2 and ERC1-ALK, the latter successfully treated by targeted-therapy. ALK/NTRK fusion partners TPR and KANK1 suggest unusual high-grade morphology/behavior. Clinicoradiologic, morphologic, and phenotypic algorithms can prompt molecular-targeted immunostains or NGS for final classification and promising inhibitor therapy.

Spindle cell neoplasm with EML4-ALK gene fusion presenting as an intraosseous vertebral mass

In this article, we describe a spindle cell neoplasm harboring an EML4-ALK gene fusion presenting as an intraosseous vertebral mass with extension into the adjacent soft tissue in a 65-year-old man. Histologically, the lesion was characterized by the presence of monotonous, cytologically bland spindle cells with loose myxoedematous stroma and interspersed areas of amianthoid-like collagen fiber deposition. Immunohistochemistry demonstrated strong diffuse staining for CD34 and S100, with absent immunoreactivity for SOX10. At 1 year of follow-up after resection, there is no evidence of local recurrence or metastatic disease. This case adds to the clinical and pathologic spectrum of the recently described group of kinase fusion-positive spindle cell neoplasms and represents the first reported intra-osseous example. The presence of ALK rearrangement in this lesion represents a potential therapeutic target, if clinically indicated.

AICA-ribosiduria due to ATIC deficiency: Delineation of the phenotype with three novel cases, and long-term update on the first case

5-Amino-4-imidazolecarboxamide-ribosiduria (AICA)-ribosiduria is an exceedingly rare autosomal recessive condition resulting from the disruption of the bifunctional purine biosynthesis protein PURH (ATIC), which catalyzes the last two steps of de novo purine synthesis. It is characterized biochemically by the accumulation of AICA-riboside in urine. AICA-ribosiduria had been reported in only one individual, 15 years ago. In this article, we report three novel cases of AICA-ribosiduria from two independent families, with two novel pathogenic variants in ATIC. We also provide a clinical update on the first patient. Based on the phenotypic features shared by these four patients, we define AICA-ribosiduria as the syndromic association of severe-to-profound global neurodevelopmental impairment, severe visual impairment due to chorioretinal atrophy, ante-postnatal growth impairment, and severe scoliosis. Dysmorphic features were observed in all four cases, especially neonatal/infancy coarse facies with upturned nose. Early-onset epilepsy is frequent and can be pharmacoresistant. Less frequently observed features are aortic coarctation, chronic hepatic cytolysis, minor genital malformations, and nephrocalcinosis. Alteration of the transformylase activity of ATIC might result in a more severe impairment than the alteration of the cyclohydrolase activity. Data from literature points toward a cytotoxic mechanism of the accumulated AICA-riboside.

Inflammatory myofibroblastic tumor of bone harboring an ALK gene amplification

Inflammatory myofibroblastic tumor (IMT) is a neoplastic proliferation of myofibroblastic/fibroblastic cells with a variable admixture of inflammatory cells. It primarily affects soft tissue and viscera of children and young adults. IMT occurring in bone is extremely rare. Approximately 50% of IMTs carry a clonal rearrangement of the anaplastic lymphoma kinase (ALK) gene, while other receptor tyrosine kinase gene rearrangements have been seen in a small subset of IMT. Herein, we report the first case of IMT which harbors an ALK gene amplification rather than a rearrangement thus resulting in overexpression of the protein, arising from the femur of a 24-year-old man. Our case provides a novel pathogenesis for IMT. An overview of cytogenetic abnormalities of IMT is also integrated into this report.