Uniportal video-assisted thoracoscopic fissureless right upper lobe anterior segmentectomy for inflammatory myofibroblastic tumor:A case report

BACKGROUND Inflammatory myofibroblastic tumors(IMTs)are exceptionally rare neoplasms with intermediate malignant potential.Surgery is the accepted treatment option,aiming for complete resection with clear margins.CASE SUMMARY A 39-year-old woman presented with a growing solitary pulmonary nodule measuring 2.0 cm in the right upper lobe(RUL)of the lung.The patient underwent a RUL anterior segmentectomy using uniportal video-assisted thoracoscopy.A preliminary tissue diagnosis indicated malignancy;however,it was later revised to an IMTs.Due to the absence of a minor fissure between the right upper and middle lobes,an alternative resection approach was necessary.Therefore,we utilized indocyanine green injection to aid in delineating the intersegmental plane.Following an uneventful recovery,the patient was discharged on the third postoperative day.Thereafter,annual chest tomography scans were scheduled to monitor for potential local recurrence.CONCLUSION This case underscores the challenges in diagnosing and managing IMTs,showing the importance of accurate pathologic assessments and tailored surgical strategies.

Perianal superficial CD34-positive fibroblastic tumor: A case report

BACKGROUND Superficial CD34-positive fibroblast tumors(SCPFTs)are newly recognized fibroblast and myofibroblast tumors representing intermediate tumors.To the best of our knowledge,fewer than 50 cases have been reported.Perianal SCPFT has not been previously reported.CASE SUMMARY A 55-year-old man was hospitalized upon discovering a painless perianal lump 10 d prior.Physical examination showed a lump of approximately 3 cm×4 cm in the 7 to 8 o’clock direction in the perianal area.Perianal abscess was considered the primary diagnosis.Lump removal surgery was performed under epidural anesthesia.Postoperative pathology showed a well-circumscribed,soft tissuederived,spindle-cell tumor with strong CD34 positivity by immunohistochemistry.The final diagnosis was perianal SCPFT.There were no complications,and the patient was followed for more than 8 mo without recurrence or metastasis.CONCLUSION We report a case of perianal superficial CD34-positive fibroblast tumor.This rare mesenchymal neoplasm has distinctive histomorphology,which is important for diagnosis.Comprehensive consideration of clinical information,imaging,histology,and immunohistochemistry is important for diagnosis.

Sclerosing epithelioid fibrosarcoma of the pancreas:A case report

BACKGROUND A sclerosing epithelioid fibrosarcoma(SEF)is a rare malignant fibroblastic soft tissue tumor that rarely occurs in intra-abdominal organs.A case of a SEF in the pancreatic head is reported herein,including its clinical manifestations,preoperative imaging features,gross specimen and pathological findings.CASE SUMMARY A 33-year-old male patient was admitted to Peking Union Medical College Hospital in December 2023 due to a one-year history of intermittent upper abdominal pain and the discovery of a pancreatic mass.The patient underwent an enhanced computed tomography scan of the abdomen,which revealed a welldefined,round mass with clear borders and calcifications in the pancreatic head.The mass exhibited progressive,uneven mild enhancement,measuring approximately 6.6 cm×6.3 cm.The patient underwent laparoscopic pylorus-preserving pancreaticoduodenectomy.Postoperative pathological examination revealed that the lesion was consistent with a SEF.At the 3-month postoperative follow-up,the patient did not report any short-term complications,and there were no signs of tumor recurrence.CONCLUSION SEFs are rare malignant fibrous soft tissue tumors.SEFs rarely develop in the pancreas,and its preoperative diagnosis depends on imaging findings,with confirmation depending on pathological examination and immunohistochemistry.Currently,only four cases of pancreatic SEF have been reported in studies written in English.This case is the first reported case of a pancreatic SEF by a clinical physician.

Identification of the involvement of LOXL4 in generation of keratocystic odontogenic tumors by RNA-Seq analysis

Keratocystic odontogenic tumors （KCOT） are benign, locally aggressive intraosseous tumors of odontogenic origin. KCOT have a higher stromal microvessel density （MVD） than dentigerous cysts （DC） and normal oral mucosa. To identify genes in the stroma of KCOT involved in tumor development and progression, RNA sequencing （RNA-Seq） was performed using samples from KCOT and primary stromal fibroblasts isolated from gingival tissues. Seven candidate genes that possess a function potentially related to KCOT progression were selected and their expression levels were confirmed by quantitative PCR, immunohistochemistry and enzyme-linked immunosorbent assay. Expression of lysyl oxidase-like 4 （LOXL4）, the only candidate gene that encodes a secreted protein, was enhanced at both the mRNA and protein levels in KCOT stromal tissues and primary KCOT stromal fibroblasts compared to control tissues and primary fibroblasts （P〈0.05）. In vitro, high expression of LOXL4 could enhance proliferation and migration of the human umbilical vein endothelial cells （HUVECs）. There was a significant, positive correlation between LOXL4 protein expression and MVD in stroma of KCOT and control tissues （r=0.882）. These data suggest that abnormal expression of LOXL4 of KCOT may enhance angiogenesis in KCOT, which may help to promote the locally aggressive biological behavior of KCOT.

Exosomes derived from tumor adjacent fibroblasts efficiently target pancreatic tumors

The application of extracellular vesicles,particularly exosomes(EXs),is rapidly expanding in the field of medicine,owing to their remarkable properties as natural carriers of biological cargo.This study investigates utilization of exosomes derived from stromal cells of tumor adjacent normal tissues(NAF-EXs)for personalized medicine,which can be derived at the time of diagnosis by endoscopic ultrasound.Herein,we show that exosomes(EXs)derived from NAFs demonstrate differential bio-physical characteristics,efficient cellular internalization,drug loading efficiency,pancreatic tumor targeting and delivery of payloads.NAF-derived EXs(NAF-EXs)were used for loading ormeloxifene(ORM),a potent anti-cancer and desmoplasia inhibitor as a model drug.We found that ORM maintains normal fibroblast cell phenotype and renders them incompatible to be triggered for a CAF-like phenotype,which may be due to regulation of Ca^(2+) influx in fibroblast cells.NAF-EXs-ORM effectively blocked oncogenic signaling pathways involved in desmoplasia and epithelial mesenchymal transition(EMT)and repressed tumor growth in xenograft mouse model.In conclusion,our data suggests preferential tropism of NAF-EXs for PDAC tumors,thus imply feasibility of developing a novel personalized medicine for PDAC patients using autologous NAF-EXs for improved therapeutic outcome of anti-cancer drugs.Additionally,it provides the opportunity of utilizing this biological scaffold for effective therapeutics in combination with standard therapeutic regimen.