Endoscopic submucosal tunnel dissection for largesuperficial esophageal squamous cell neoplasms

Endoscopic submucosal dissection(ESD)is a wellestablished treatment for superficial esophageal squamous cell neoplasms(SESCNs)with no risk of lymphatic metastasis.However,for large SESCNs,especially when exceeding two-thirds of the esophageal circumference,conventional ESD is time-consuming and has an increased risk of adverse events.Based on the submucosal tunnel conception,endoscopic submucosal tunnel dissection(ESTD)was first introduced by us to remove large SESCNs,with excellent results.Studies from different centers also reported favorable results.Compared with conventional ESD,ESTD has a more rapid dissection speed and R0 resection rate.Currently in China,ESTD for large SESCNs is an important part of the digestive endoscopic tunnel technique,as is peroral endoscopic myotomy for achalasia and submucosal tunnel endoscopic resection for submucosal tumors of the muscularis propria.However,not all patients with SESCNs are candidates for ESTD,and postoperative esophageal strictures should also be taken into consideration,especially for lesions with a circumference greater than three-quarters.In this article,we describe our experience,review the literature of ESTD,and provide detailed information on indications,standard procedures,outcomes,and complications of ESTD.

Plasma Cell Neoplasms, Clinicopathological Characteristics and Immunophenotype of 21 Patients

Introduction: Plasma cell neoplasms are monoclonal proliferations characterized by the secretion of an immunoglobulin product known as component "M" or monoclonal. The World Health Organization (WHO 2008) defines as plasma cell neoplasms the following: plasma cell myeloma, plasmacytoma and those syndromes defined by immunoglobulin deposits and primary amyloidosis, The objective of the present work was to correlate their clinical, morphological and phenotype characteristics in 21 patients. Material and Methods: A 2-year retrospective review was performed of the files of the surgical pathology laboratory and of the hematology service of the General Hospital of Mexico, searching for patients with a diagnosis of plasma cell neoplasm. We analyzed the following variables: age, gender, clinical symptoms, evolution, localization, laboratory tests, morphology, and expression of immunohistochemical markers. Of the 21 patients, 12 (57.1%) corresponded to plasma cell myelomas and 9 (42.8%) were plasmacytomas (seven extraosseous and two solitary bone plasmacytoma);women predominated with 61.4% and age ranged between 22 and 84 years. Mass and epistaxis were observed in the patients with plasmacytomas, and symptoms of medullary compression and anemia were observed in those patients with plasma cell myeloma. The time of symptomatology varied from 3 to 12 months. Laboratory tests revealed that lactate dehydrogenase (LDH), beta 2 microglobulin, C-reactive protein were altered and that hypercalcemia and anemia were present more in the systemic form of the disease. Treatment depended on the clinical staging and laboratory data. Mature forms predominated morphologically. Immunohistochemical stain revealed a constant expression for CD 138, six patients expressed CD 56, and expression of the Kappa and Lambda light chains was while.

Short term results of endoscopic submucosal dissection in superficial esophageal squamous cell neoplasms

AIM: To evaluate the efficacy of endoscopic submucosal dissection for superficial esophageal squamous cell neoplasms. METHODS: Between July 2007 and March 2009, 27 consecutive superficial esophageal squamous cell neoplasms in 25 enrolled patients were treated by endoscopic submucosal dissection. The therapeutic efficacy, complications, and follow-up results were assessed. RESULTS: The mean size of the lesions was 21 ± 13 mm (range 2-55 mm); the mean size of the resection specimens was 32 ± 12 mm (range 10-70 mm). The enblock resection rate was 100% (27/27), and en block resection with tumor-free lateral/basal margins was 88.9% (24/27). Perforation occurred in 1 patient who was managed by conservative medical treatments. None of the patients developed local recurrence or distant metastasis in the follow-up period. CONCLUSION: Endoscopic submucosal dissection is applicable to superficial esophageal squamous cell neoplasms with promising results.

Gastrointestinal bleeding as initial presentation of extramedullary plasma cell neoplasms: A case report and review of the literature

BACKGROUND Plasma-cell neoplasms rarely involve the gastrointestinal tract and manifest as gastrointestinal bleeding. Plasmablastic myeloma is an aggressive plasma cell neoplasm associated with poor outcomes. A small number of cases with gastrointestinal involvement is reported in the literature and therefore high index of suspicion is essential for avoiding delays in diagnosis and treatment.CASE SUMMARY Our aim is to present our experience of a 70-year-old patient with a secondary presentation of plasmablastic myeloma manifesting as unstable upper gastrointestinal bleeding and to review the literature with the view to consolidate and discuss information about diagnosis and management of this rare entity. In addition to our case, a literature search(Pub Med database) of case reports of extramedullary plasma cell neoplasms manifesting as upper gastrointestinal bleeding was performed. Twenty-seven cases of extramedullary plasmacytoma(EMP) involving the stomach and small bowel presenting with upper gastrointestinal bleeding were retrieved. The majority of patients were males(67%). The average age on diagnosis was 62.7 years. The most common site of presentation was the stomach(41%), followed by the duodenum(15%). The most common presenting complaint was melena(44%). In the majority of cases, the EMPs were a secondary manifestation(63%) at the background of multiple myeloma(26%), plasmablastic myeloma(7%) or high-grade plasma cell myeloma(4%). Oesophagogastroscopy was the main diagnostic modality and chemotherapy the preferred treatment option for secondary EMPs.CONCLUSION Despite their rare presentation, upper gastrointestinal EMPs should be considered in the differential diagnosis of patients with gastrointestinal bleeding especially in the presence of systemic haematological malignancy.

How and Why Do Gestational Trophoblastic Neoplasms Overproduce Human Chorionic Gonadotropin?

From the published data, the present mini-review attempts to answer two fundamental questions about the gestational trophoblastic neoplasms. In addition, it extrapolates the findings to other cancers that produce small amounts of hCG and how a novel therapies could be developed.

Therapy-related myeloid neoplasms - what have we learned so far?

Therapy-related myeloid neoplasms are neoplastic processes arising as a result of chemotherapy, radiation therapy, or a combination of these modalities given for a primary condition. The disease biology varies based on the etiology and treatment modalities patients receive for their primary condition. Topoisomerase Ⅱ inhibitor therapy results in balanced translocations. Alkylating agents, characteristically, give rise to more complex karyotypes and mutations in p53. Other etiologies include radiation therapy, high-dose chemotherapy with autologous stem cell transplantation and telomere dysfunction. Poor-risk cytogenetic abnormalities are more prevalent than they are in de novo leukemias and the prognosis of these patients is uniformly dismal. Outcome varies according to cytogenetic risk group. Treatment recommendations should be based on performance status and karyotype. An in-depth understanding of risk factors that lead to the development of therapyrelated myeloid neoplasms would help developing riskadapted treatment protocols and monitoring patients after treatment for the primary condition, translating into reduced incidence, early detection and timely treatment.

Endoscopic submucosal dissection for superficial esophageal neoplasms

Endoscopic submucosal dissection(ESD) is currently accepted as the major treatment modality for superficial neoplasms in the gastrointestinal tract including the esophagus.An important advantage of ESD is its effectiveness in resecting lesions regardless of their size and severity of fibrosis.Based on excellent outcomes for esophageal neoplasms with a small likelihood of lymph node metastasis,the number of ESD candidates has increased.On the other hand,ESD still requires highly skilled endoscopists due to technical difficulties.To avoid unnecessary complications including perforation and postoperative stricture,the indications for ESD require careful consideration and a full understanding of this modality.This article,in the highlight topic series,provides detailed information on the indication,procedure,outcome,complications and their prevention in ESD of superficial esophageal neoplasms.

Small Cell Neuroendocrine Carcinoma of the Vulva: Case Report and Literature Review

Background: Neuroendocrine neoplasms are those that develop from a neuroendocrine cell. They most commonly affect the lungs, gastrointestinal tract, and pancreas, being rare conditions in the female genital tract. When present, these neoplasms often manifest with nonspecific signs and symptoms such as pain, itching, swelling, single-focus lesions, bleeding, and enlargement of inguinal lymph nodes, in addition to the presence of progressively enlarging vulvar nodules. Consequently, the diagnostic investigation involves histopathological examination and confirmation through immunohistochemistry. Objective: To present a comprehensive understanding of this rarely studied pathology. The primary objective is to provide valuable insights that could aid in the future development of universally applicable treatment guidelines. Case Presentation: A 57-year-old female, with no prior comorbidities, menopause at 36, who presented with a left vulvar nodule accompanied by intense pain and swelling, later diagnosed with small cell neuroendocrine carcinoma in the vulva. Conclusion: This case report highlights the importance of enhancing our knowledge regarding small cell neuroendocrine carcinoma in the vulva, given its scarcity in medical literature. The information presented here underscores the need for standardized diagnostic and treatment approaches, paving the way for future consensus on managing this uncommon but challenging neoplasm.

Feasibility of laparoscopic isolated caudate lobe resection for rare hepatic mesenchymal neoplasms

BACKGROUND Mesenchymal tumors such as perivascular epithelioid cell neoplasm(PEComa)and inflammatory pseudotumor-like follicular dendritic cell sarcoma(IPT-like FDC sarcoma)are relatively uncommon in the liver and are particularly rare in the caudate lobe.The clinical manifestations and available imaging tests lack specificity for hepatic mesenchymal tumors.To the best of our knowledge,no caudate PEComa or IPT-like FDC sarcoma has been completely resected by laparoscopy.The standard laparoscopic technique,surgical approaches,and tumor margins for potentially malignant or malignant caudate mesenchymal tumors are still being explored.AIM To assess both the safety and feasibility of laparoscopic resection for rare caudate mesenchymal neoplasms.METHODS Eleven patients who underwent isolated caudate lobe resection from 2003 to 2017 were identified from a prospective database.Three consecutive patients with rare caudate mesenchymal tumors underwent laparoscopic resection.Patient demographic data,intraoperative parameters,and postoperative outcomes were assessed and compared with the open surgery group.RESULTS All procedures for the three resection patients with caudate mesenchymal tumors were completed using a total laparoscopic technique by two different approaches.The average operative time was 226 min,and the estimated blood loss was 133 mL.The average length of postoperative hospital stay was 6.3±0.3 d for the laparoscopy group and 15.5±2.3 d for the open surgery group(P<0.05).There were no perioperative complications or patient deaths in this series.CONCLUSION Laparoscopic isolated caudate lobe resection for rare mesenchymal neoplasms is a feasible and curative surgical option in selected patients.

The anti-neoplastic effects of metformin modulate the acquired phenotype of fbroblast cells in the breast cancer-normal fbroblast co-culture system

Intracellular communications between breast cancer and fibroblast cells were reported to be involved in cancer proliferation,growth,and therapy resitance.The hallmarks of cancer fibroblast interactions,consisting of caveolin 1(Cav1)and mono-carboxylate ransporter 4(MCT4)(metabolic coupling markers),along with IL-6,TGFB,and lactate secretion,are considered robust biomarkers predicting recurrence and metastasis.In order to promote a novel phenotype in normal fibroblasts,we predicted that breast cancer cells could be able to cause loss of Cavl and increase of MCT4,as well as elevate IL 6 and TGF in nearby nomal fibroblasts.We created a co culture model using breast cancer(4T1)and normal fibroblast(NIH3T3)cell lines cultured under specific experimental conditions in order to directly test our theory.Moreover,we show that long-term co-culture of breast cancer cells and normal fibroblasts promotes loss of Cavl and gain of MCT4 in adjacent fibroblasts and increase lactate secretion.These results were validated using the monoculture of each group separately as a control.In this system,we show that me tformin inhibits IL-6 and TGFB secretion and re expresses Cavl in both cells.However,MCT4 and lactate stayed high after treatment with metformin.In conclusion,our work shows that co-culture with breast cancer cells may cause signifcant alterations in the phenotype and secretion of normal fibroblasts.Metformin,however,may change this state and affect fibroblasts'acquired phenotypes.Moreover,mitochondrial inhibition by metformin after 8 days of treatment,signi ficantly hinders tumor growth in mouse model of breast cancer.

Subgroups of peripheral immune effector cells in cervical cancer patients are more sensitive to radiation therapy than chemotherapy

Background:CD8 positive T lymphocytes and natural killer(NK)cells in the peripheral blood of cervical cancer patients exhibit varying sensitivities to radiotherapy and chemotherapy.Methods:A total of 50 healthy peoples and 60 cervical cancer patients were recruited.The patients with cervical cancer were separated into two groups:radiation and chemotherapy,and blood sample were collected before and after treatment.Data on the proportion of CD8 positive T lymphocytes and NK cells were gathered for analytical evaluation.Results:Compared to healthy individuals,patients with cervical cancer exhibit a reduced proportion of CD8 positive T cells within their peripheral blood.And for patients with cervical cancer,radiation therapy has been found to be more effective than chemotherapy in increasing the proportion of CD8 positive T lymphocytes and NK cells.Conclusions:These results suggest that radiation therapy increases the levels of CD8 positive T lymphocytes and NK cells within the peripheral blood of patients with cervical cancer.The study hypothesis that the changes in the percentage of CD8 positive T lymphocytes may serve as a potential indicator for predicting treatment efficacy.

Azacitidine maintenance therapy for blastic plasmacytoid dendritic cell neoplasm allograft: A case report

BACKGROUND Blastic plasmacytoid dendritic cell neoplasm(BPDCN)is a rare,highly invasive malignant neoplasm.There is no universally accepted standard of care because of its rarity and the dearth of prospective research.It is still challenging for some patients to achieve persistent clinical remission or cure,despite the success of allogeneic hematopoietic stem cell transplantation(allo-HSCT),indicating that there is still a significant recurrence rate.We report a case of prevention of BPDCN allograft recurrence by azacitidine maintenance therapy and review the relevant literature.CASE SUMMARY We report a 41-year-old man with BPDCN who was admitted to hospital due to skin sclerosis for>5 mo’duration.BPDCN was diagnosed by combined clinical assessment and laboratory examinations.Following diagnosis,the patients underwent induction consolidation chemotherapy to achieve the first complete remission,followed by bridging allo-HSCT.Post-transplantation,azacitidine(75 mg/m2 for 7 d)was administered as maintenance therapy,with repeat administration every 4–6 wk and appropriate extension of the chemotherapy cycle.After 10 cycles,the patient has been disease free for 26 mo after transplantation.Regular assessments of bone marrow morphology,minimal residual disease,full donor chimerism,Epstein–Barr virus,and cytomegalovirus all yielded normal results with no abnormalities detected.CONCLUSION Azacitidine may be a safe and effective maintenance treatment for BPDCN following transplantation because there were no overt adverse events during the course of treatment.

Perivascular epithelioid cell tumors of the liver misdiagnosed as hepatocellular carcinoma:Three case reports

BACKGROUND Hepatic perivascular epithelioid cell neoplasms(PEComas)are rare.Diagnostic and treatment experience with hepatic PEComa remains insufficient.CASE SUMMARY Three hepatic PEComa cases are reported in this paper:One case of primary malignant hepatic PEComa,one case of benign hepatic PEComa,and one case of hepatic PEComa with an ovarian mature cystic teratoma.During preoperative imaging and pathological assessment of intraoperative frozen samples,patients were diagnosed with hepatocellular carcinoma(HCC),while postoperative pathology and immunohistochemistry subsequently revealed hepatic PEComa.Patients with hepatic PEComa which is misdiagnosed as HCC often require a wider surgical resection.It is easy to mistake them for distant metastases of hepatic PEComa and misdiagnosed as HCC,especially when it’s combined with tumors in other organs.Three patients eventually underwent partial hepatectomy.After 1-4 years of follow-up,none of the patients experienced recurrence or metastases.CONCLUSION A clear preoperative diagnosis of hepatic PEComa can reduce the scope of resection and prevent unnecessary injuries during surgery.

Genetic polymorphisms in genes regulating cell death and prognosis of patients with rectal cancer receiving postoperative chemoradiotherapy

Objective:The identification of biomarkers for predicting chemoradiotherapy efficacy is essential to optimize personalized treatment.This study determined the effects of genetic variations in genes involved in apoptosis,pyroptosis,and ferroptosis on the prognosis of patients with locally advanced rectal cancer receiving postoperative chemoradiotherapy(CRT).Methods:The Sequenom MassARRAY was used to detect 217 genetic variations in 40 genes from 300 patients with rectal cancer who received postoperative CRT.The associations between genetic variations and overall survival(OS)were evaluated using hazard ratios(HRs)and 95%confidence intervals(CIs)computed using a Cox proportional regression model.Functional experiments were performed to determine the functions of the arachidonate 5-lipoxygenase(ALOX5)gene and the ALOX5 rs702365 variant.Results:We detected 16 genetic polymorphisms in CASP3,CASP7,TRAILR2,GSDME,CASP4,HO-1,ALOX5,GPX4,and NRF2 that were significantly associated with OS in the additive model(P<0.05).There was a substantial cumulative effect of three genetic polymorphisms(CASP4 rs571407,ALOX5 rs2242332,and HO-1 rs17883419)on OS.Genetic variations in the CASP4 and ALOX5 gene haplotypes were associated with a higher OS.We demonstrated,for the first time,that rs702365[G]>[C]represses ALOX5 transcription and corollary experiments suggested that ALOX5 may promote colon cancer cell growth by mediating an inflammatory response.Conclusions:Polymorphisms in genes regulating cell death may play essential roles in the prognosis of patients with rectal cancer who are treated with postoperative CRT and may serve as potential genetic biomarkers for individualized treatment.

Co-existing squamous cell carcinoma and chronic myelomonocytic leukemia with ASXL1 and EZH2 gene mutations:A case report

BACKGROUND Chronic myelomonocytic leukemia(CMML),a rare clonal hematopoietic stem cell disorder characterized by myelodysplastic syndrome and myeloproliferative neoplasms,has a generally poor prognosis,and easily progresses to acute myeloid leukemia.The simultaneous incidence of hematologic malignancies and solid tumors is extremely low,and CMML coinciding with lung malignancies is even rarer.Here,we report a case of CMML,with ASXL1 and EZH2 gene mutations,combined with non-small cell lung cancer(lung squamous cell carcinoma).CASE SUMMARY A 63-year-old male,suffering from toothache accompanied by coughing,sputum,and bloody sputum for three months,was given a blood test after experiencing continuous bleeding resulting from a tooth extraction at a local hospital.Based on morphological results,the patient was diagnosed with CMML and bronchoscopy was performed in situ to confirm the diagnosis of squamous cell carcinoma in the lower lobe of the lung.After receiving azacitidine,programmed cell death protein 1,and platinum-based chemotherapy drugs,the patient developed severe myelosuppression and eventually fatal leukocyte stasis and dyspnea.CONCLUSION During the treatment and observation of CMML and be vigilant of the growth of multiple primary malignant tumors.

Diagnosing upper tract urothelial carcinoma: A review of the role of diagnostic ureteroscopy and novel developments over last two decades

Objective: The role of ureteroscopy in the diagnosis of upper tract urothelial carcinoma is yet to be fully determined. We aimed to provide an up to date evaluation of its role and the emerging technologies in the field.Methods: A literature search of the last two decades (from 24th May, 2001 to 24th May, 2021) was carried out identifying 147 papers for potential inclusion within this narrative review.Results: Diagnostic ureteroscopy is undeniably useful in its ability to visualise and biopsy indeterminate lesions, and to risk stratify malignant lesions that may be suitable for kidney sparing surgery. However, an increased risk of intravesical recurrence following nephroureterectomy when a prior diagnostic ureteroscopy has been performed, inadequate sampling at biopsy, complications from the procedure, and difficult ureteric access are all potential drawbacks. Furthermore, whilst generally an accurate diagnostic procedure, it risks missing carcinoma in-situ lesions. Despite this, evidence shows that routine use of ureteroscopy changes the management of patients in a large proportion of cases, preventing unnecessary surgery or facilitating kidney sparing surgery. The overall rate of complications is low, and improved biopsy techniques and the use of tissue biomarkers for improved staging and grading are encouraging. The risks of delays to definitive management and post-ureteroscopy intravesical recurrence do not seem to affect survival, and trials are in progress to determine whether intravesical therapy can mitigate the latter. Further promising techniques are being investigated to improve shortcomings, particularly in relation to improved diagnosis of carcinoma in situ and preoperative staging.Conclusion: Ureteroscopy has a role in the diagnosis of upper tract malignancy, though whether it should be used routinely is yet to be determined.

Intraoperative photodynamic therapy for tracheal mass in non-small cell lung cancer:A case report

BACKGROUND Tracheal neoplasms represent less than 0.1%of all malignancies and have no established treatment guidelines.Surgical resection with reconstruction is the primary treatment.This study demonstrates successful treatment of concurrent lung and tracheal tumors using surgical excision and intraoperative photodynamic therapy(PDT),highlighting the effectiveness and safety of this approach.CASE SUMMARY A 74-year-old male with a history of smoking and chronic obstructive pulmonary disease was diagnosed with tracheal squamous cell carcinoma and right lower lobe adenocarcinoma.A multidisciplinary team created a treatment plan involving tumor resection and PDT.The tracheal tumor was removed through a tracheal incision and this was followed by intraluminal PDT.The trachea was repaired and a right lower lobectomy was performed.The patient received a second PDT treatment postoperatively and was discharged 10 d after the tracheal surgery,without complications.He then underwent platinum-based chemotherapy for lymphovascular invasion of lung cancer.Three-month postoperative bronchoscopy revealed normal tracheal mucosa with a scar at the resection site and no evidence of tumor recurrence in the trachea or lung.CONCLUSION Our case of concurrent tracheal and lung cancers was successfully treated with surgical excision and intraoperative PDT which proved safe and effective in this patient.

Granular cell tumor of the breast:A case report and review of literature

BACKGROUND Granular cell tumor(GCT)of the breast(GCTB)is a rare neoplasm that can exhibit malignant characteristics both clinically and radiologically.This tumor can also coexist and colocalize with breast carcinoma.CASE SUMMARY We present a patient with this uncommon tumor and discuss the diagnostic and therapeutic approaches in order to further the knowledge of GCTB and prevent misdiagnosis and overtreatment.The characteristics of the tumor,methods of diagnosis,therapy and postoperative pathological outcomes were analyzed,and relevant literatures of GCTs were reviewed.The patient underwent surgery after core needle biopsy,and the excised neoplasm was sent for pathological examination.Histological analysis revealed nests of cells with abundant pink granular cytoplasm,confirming the diagnosis of GCTB.CONCLUSION As manifestations of GCT and malignancy can mimic each other,a careful histological examination is essential before major surgery.Treatment consisting of complete excision with close clinical follow-up is recommended.

Effects of tachyplesin on the morphology and ultrastructure of human gastric carcinoma cell line BGC-823

AIM To investigate the morphological andultrastructural changes in the human gastriccarcinoma cell line BGC-823 after being treatedwith tachyplesin.METHODS Tachyplesin was isolated from acidextracts of Chinese horseshoe crab(Tachypleustridentatus)hemocytes.BGC-823 cells and thecells treated with 2.0mg/L tachyplesin wereexamined respectively under light microscope,scanning and transmission electron microscope.RESULTS BGC-823 cells had undergone therestorational alteration in morphology andultrastructure after tachyplesin treatment.Thechanges were as follows:the shape of cells wasunanimous,the volume enlarged and cellsturned to be flat and spread,the nucleo-cytoplasmic ratio lessened and nuclear shapebecame rather regular,the number of nucleolusreduced and its volume lessened,heter-chromatin decreased while euchromatinincreased in nucleus.In the cytoplasm,mitochondria grew in number with consistentstructure relatively,Golgi complex turned to betypical and well-developed,rough endoplasmicreticulum increased and polyribosomedecreased.The microvilli at cellular surfacewere rare and the filopodia reduced whilelamellipodia increased at the cell edge.CONCLUSION Tachyplesin could alter themalignant morphological and ultrastructuralcharacteristics of human gastric carcinoma cellseffectively and have a certain inducing differen-tiation effect on human gastric carcinoma cells.

Human papillomavirus 16 E6 is associated with the nuclear matrix of esophageal carcinoma cells

AIM: To explore the etiologic role of HPV infection in esophageal carcinoma, and the association of HPV-16 E6with the nuclear metrix of carcinoma cells.METHODS: Two esophageal carcinoma cell lines, EC/CUHK1 and EC/CUHK2, were tested for HPV-16 E6subgenetic fragment by polymerase chain reaction amplification of virus DNA associated nuclear matrix. RT-PCR and immunocytochemistry were also used to visualizethe expression of E6 subgene in the cells.RESULTS: The HPV-16 E6 subgenetic fragment wes found to be present in nuclear metrix-associeted DNA, E6oncoprotein localized in the nucleus where it is tightly associated with nuclear matrix after sequential extraction in EC/CUHK2 cells. It was not detected, however, in EC/CUHK1 cells.CONCLUSION: The interaction between HPV-16 E6 and nuclear matrix may contribute to the virus induced carcinogenesis in esophageal carcinoma.