Case report: NTRK1-rearranged cervical sarcoma with fibrosarcoma like morphology presenting in a 13-year-old managed with a neo-adjuvant TRK-inhibitor and surgical excision

The "Other" Uterine Mesenchymal Neoplasms: Recent Developments and Emerging Entities

Uterine mesenchymal neoplasms are a challenging group of tumors that often show overlapping morphologic features and immunohistochemical profiles. The increasing use of molecular testing in these tumors has enabled a better appreciation of their pathobiology, resulting in a wave of emerging neoplasms and improved characterization of ones previously considered exceptionally rare. Identification of specific molecular alterations has permitted targeted therapy options in tumors that were typically unresponsive to conventional therapies, as well as recognition that a subset can have a hereditary basis. This review will discuss the more "common" of the uncommon uterine mesenchymal neoplasms, including inflammatory myofibroblastic tumor, perivascular epithelioid cell tumor, uterine tumor resembling ovarian sex cord tumor, and embryonal rhabdomyosarcoma. This will be followed by an overview of emerging entities, including NTRK -rearranged uterine sarcoma, SMARCA4 -deficient uterine sarcoma, KAT6B/A::KANSL1 fusion uterine sarcoma, and MEIS1::NCOA2/1 fusion sarcoma.

The mutual interplay between NTRK fusion genes and human papillomavirus infection in cervical cancer progression (Review)

Cervical cancer is a significant global health concern, with a substantial portion of cases attributed to human papillomavirus (HPV) infection. Recent advancements in molecular profiling have identified distinct subtypes of cervical cancer based on their genomic alterations. One such subgroup is neurotrophic tropomyosin receptor kinase (NTRK) fusion-positive cervical cancers, characterized by gene fusions involving the NTRK genes. Although both NTRK fusion genes and HPV infections are independently recognized as significant risk factors in cervical cancer, their interplay and mutual effects on cancer progression are not yet fully understood. The present review is the first of its kind to explore the potential interplay between NTRK fusion genes and HPV infections. It surveys in detail how their combined effect can influence the signaling pathways during cervical cancer development and progression. Moreover, the present study discussed the clinical features, histopathological examinations, treatment procedures and follow-up outcomes of NTRK-fusion gene-positive cervical cancer. The present review may help in the understanding of the management and treatment of such rare, lethal and resistant cervical cancers.

Uterine Neurotrophic Tyrosine Receptor Kinase Rearranged Spindle Cell Neoplasms: Three Cases of an Emerging Entity

Uterine sarcomas are rare; most are either smooth muscle or endometrial stromal in origin. Recent molecular advances have identified several, genetically defined entities with specific morphologic, clinicopathological associations, and therapeutic options. We report 3 cases of uterine neurotrophic tyrosine receptor kinase ( NTRK )-rearranged spindle cell neoplasms," currently classified as "emerging entities" in the WHO Classification of Female Genital Tract Tumors, 2020, Fifth Edition. The affected patients were 32, 34, and 42 years of age. Two patients presented with vaginal bleeding; the third presented with a cervical mass found incidentally during laparoscopy for an ectopic gestation. All 3 tumors were polypoid masses that distorted the cervix. Microscopically, they comprised cellular, fascicular, and storiform, plump spindle cells, with occasional rounded cells, and frequent mitoses (4-48/10 high power fields) in a myxoid stroma. All 3 cases showed entrapment of benign cervical glands. Inflammatory cell infiltrates, including plasma cells, were noted in all 3 tumors. One case had tumor cell necrosis, osteoid-like material, and osteoclast-like giant cells and showed lymphovascular invasion. Immunohistochemically, our cases showed patchy S100 (2/3) and CD34 (3/3) positivity. CD10 was positive in 2/3 cases. 3/3 cases showed pan-tropomyosin receptor kinase positivity (cytoplasmic). The NTRK -translocations demonstrated were: NTRK1::TMP3, NTRK1::TPR, and NTRK3::SPECC1L . Two of the patients had extensive disease and underwent chemotherapy. Larotrectinib was approved for one patient who demonstrated a striking reduction in tumor volume upon initiation of this treatment.

[Diagnosis of uterine sarcomas and rare uterine mesenchymal tumours with malignant potential. Guidelines of the French Sarcoma Group and Rare Gynaecological Tumours]

The landscape of uterine sarcomas is becoming more complex with the description of new entities associated with recurrent driver molecular alterations. Uterine sarcomas, in analogy with soft tissue sarcomas, are distinguished into complex genomic and simple genomic sarcomas. Leiomyosarcomas and undifferentiated uterine sarcomas belong to complex genomic sarcomas group. Low-grade and high-grade endometrial stromal sarcomas, other rare tumors associated with fusion transcripts (such as NTRK, PDGFB, ALK, RET ROS1) and SMARCA4-deficient uterine sarcoma are considered simple genomic sarcomas. The most common uterine sarcoma are first leiomyosarcoma and secondly endometrial stromal sarcomas. Three different histological subtypes of leiomyosarcoma (fusiform, myxoid, epithelioid) are identified, myxoid and epithelioid leiomyosarcoma being more aggressive than fusiform leiomyosarcoma. The distinction between low-grade and high-grade endometrial stromal sarcoma is primarily morphological and immunohistochemical and the detection of fusion transcripts can help the diagnosis. Uterine PEComa is a rare tumor, which is distinguished into borderline and malignant, according to a risk assessment algorithm. Embryonal rhabdomyosarcoma of the uterine cervix is more common in children but can also occur in adult women. Embryonal rhabdomyosarcoma of the uterine cervix is almost always DICER1 mutated, unlike that of the vagina which is wild-type DICER1, and adenosarcoma which can be DICER1 mutated but with less frequency. Among the emerging entities, sarcomas associated with fusion transcripts involving the NTRK, ALK, PDGFB genes benefit from targeted therapy. The integration of molecular data with histology and clinical data allows better identification of uterine sarcomas in order to better treat them.

Conservative surgical treatment with fertility preservation in a young adult with NTRK rearranged spindle cell neoplasm of the uterine cervix

In depth molecular studies are constantly expanding our understanding and refining the classification of gynecological neoplasms. NTRK rearranged spindle cell neoplasms of the lower genital tract are an emerging entity, of particular interest due to possible targeted treatment with selective kinase inhibitors. Nonetheless, surgery remains the initial treatment of choice. We present the case of a 24-year-old patient suffering from a NTRK rearranged spindle cell neoplasm of the uterine cervix which was treated with a fertility preserving conservative surgical approach.

NTRK -Rearranged Uterine Sarcomas: Clinicopathologic Features of 15 Cases, Literature Review, and Risk Stratification

NTRK -rearranged uterine sarcomas are rare spindle cell neoplasms that typically arise in the uterine cervix of young women. Some tumors recur or metastasize, but features which predict behavior have not been identified to date. Distinguishing these tumors from morphologic mimics is significant because patients with advanced stage disease may be treated with TRK inhibitors. Herein, we present 15 cases of NTRK- rearranged uterine sarcomas, the largest series to date. Median patient age was 35 years (range: 16 to 61). The majority arose in the uterine cervix (n=14) and all but 2 were organ-confined at diagnosis. Tumors were composed of an infiltrative, fascicular proliferation of spindle cells and most showed mild-to-moderate cytologic atypia. All were pan-TRK positive by immunohistochemistry (13/13); S100 (11/13) and CD34 (6/10) were usually positive. RNA or DNA sequencing found NTRK1 (10/13) and NTRK3 (3/13) fusions with partners TPR , TPM3 , EML4 , TFG , SPECC1L , C16orf72 , and IRF2BP2 . Unusual morphology was seen in 2 tumors which were originally diagnosed as unclassifiable uterine sarcomas, 1 of which also harbored TP53 mutations. Follow up was available for 9 patients, of whom 3 died of disease. By incorporating outcome data of previously reported tumors, adverse prognostic features were identified, including a mitotic index ≥8 per 10 high-power fields, lymphovascular invasion, necrosis, and NTRK3 fusion. Patients with tumors which lacked any of these 4 features had an excellent prognosis. This study expands the morphologic spectrum of NTRK -rearranged uterine sarcomas and identifies features which can be used for risk stratification.

Primary NTRK-rearranged Spindle Cell Neoplasm of the Lung: A Clinicopathologic and Molecular Analysis of 3 Cases

Three cases of primary NTRK-rearranged spindle cell neoplasm of the lung with resemblance to those described in the somatic soft tissues are presented. The patients are 2 males and 1 female with age at presentation ranging from 31 to 45 years (mean, 36 y). All the 3 tumors were discovered incidentally during physical examinations. None of the patients had any prior history of mesenchymal neoplasms anywhere else. Computed tomography revealed intrapulmonary mass located in the right upper lobe, left upper lobe, and left lower lobe, respectively. All the patients underwent lobectomy. Grossly, the tumors were described as yellowish-white solid measuring in size between 1.2 and 1.8 cm (mean, 1.5 cm). Histologically, they were characterized by monomorphic spindle cells arranged in haphazard fascicles accompanied by variable stromal collagens. Nuclear atypia was mild and mitotic activity was scarce. By immunohistochemistry, the neoplastic cells in all 3 cases showed strong and diffuse staining of CD34, pan-TRK, and TrkA with variable expression of S100 protein, whereas they were negative for cytokeratin, SOX10, ALK, α-smooth muscle actin, desmin, and STAT6. Fluorescence in situ hybridization analysis revealed NTRK1 rearrangement in all 3 cases. Subsequent next-generation sequencing identified TPM3-NTRK1 fusion in 2 cases and LMNA-NTRK1 fusion in 1 case. All 3 patients are alive without the disease (median follow-up, 9 mo; range, 4 to 87 mo). The cases present herein demonstrate that NTRK-rearranged spindle cell neoplasms may occur primarily in the lung, albeit extremely rare, and should be included in the differential diagnosis of primary pulmonary spindle cell neoplasms.

Adult NTRK-rearranged spindle cell neoplasms of the viscera: with an emphasis on rare locations and heterologous elements

NTRK-rearranged mesenchymal neoplasms mostly affect the soft tissues of pediatric patients. Given the responsiveness to selective NTRK inhibitors, it remains critical to identify those ultra-rare cases occurring in the viscera of adults. In five females and two males aged 18-53 years, we characterized visceral mesenchymal tumors harboring TPM3-NTRK1 [uterine cervix (N = 2), pleura, prostate], LMNA-NTRK1 (lung), SQSTM1-NTRK3 (heart), and NTRK3 rearrangement with unknown fusion partner (colon/mesocolon) with RNA sequencing, FISH, RT-PCR, and immunohistochemistry. The tumors exhibited spindled to ovoid/epithelioid or pleomorphic cells, often arranged in fascicles, and were low-to-intermediate-grade and high-grade in three and four cases, respectively. Keloid-like stromal collagen and perivascular hyalinization was noted in five. Adenosarcoma-like appearances were observed in two, manifesting frond-like protrusions in one cervical tumor and phyllodes-like architecture in the prostatic tumor. Abrupt high-grade transformation into pleomorphic liposarcoma was found in another cervical tumor, while the pleural tumor contained intermixed rhabdomyoblasts. Pan-TRK immunostaining was positive in all cases. All cases expressed CD34, while five were S100-positive. CDKN2A homozygous deletion with concomitant p16 loss occurred in 4/7. Whole-exome sequencing identified TP53 mutation (c.672+2T>C, involving a splice site, with concomitant protein loss) in a cervical sarcoma, limited to its heterologous liposarcomatous component. At least moderate pan-TRK immunoreactivity was present in varying proportions of potential pathologic mimics, with BCOR-positive sarcoma (56%, 5/9), undifferentiated uterine sarcoma (50%, 3/6), and spindle cell/sclerosing rhabdomyosarcoma (33%, 2/6) being among the most frequent. This underscored the unsatisfactory specificity of pan-TRK immunohistochemistry and warranted molecular confirmation in the diagnosis of adult NTRK-rearranged visceral mesenchymal neoplasms. The current report highlights the ever-expanding clinicopathologic and genetic spectrum of this entity by describing the unprecedented cardiac and pleural locations and heterologous differentiation, as well as the second NTRK-rearranged "prostatic stromal sarcoma," while substantiating CDKN2A deletion as a frequent occurrence.

Update on Mesenchymal Lesions of the Lower Female Genital Tract

This article provides an update of the recent developments in mesenchymal tumors of lower genital tract. We focus on the characterization of recurrent molecular events in certain genital stromal tumors, for instance angiomyofibroblastomas and superficial myofibroblastomas. Moreover, fusions involving Tyrosine-kinases receptors (NTRK, FRFR1, RET, COL1A1-PDGFB) have been demonstrated in an emerging group of mesenchymal tumors characterized by a fibrosarcoma-like morphology and a predilection for uterine cervix of premenopausal women. We also cover the topic of smooth muscle tumors of the lower genital tract, which can be now classified using the same diagnostic criteria than their uterine counterpart..