Endorectal ultrasonographic staging of rectal carcinoma

Endorectal ultrasonography is a valuable imaging method for examination of the rectum and perirectal tissues. We assessed 50 patients with known rectal carcinoma prospectively by using a 7.0-MHz endorectal transducer to determine the depth of invasion of the rectal wall by tumor and the presence of lymphadenopathy. Tumors were staged by using the Astler-Coller modification of the Dukes staging system, and the results were compared with histologic staging of the surgical specimen. Ultrasonography had an accuracy of 80%, a sensitivity of 92%, and a specificity of 76% for detection of invasion of the perirectal fat. Ultrasonography was sensitive in the detection of perirectal lymphadenopathy but was not specific in distinguishing benign from malignant nodes.     

Pedunculated colonic lipoma prolapsing through the anus

Colorectal lipomas are the second most common benign tumors of the colon. These masses are typically incidental findings with over 94% being asymptomatic. Symptoms-classically abdominal pain, bleeding per rectum and alterations in bowel habits-may arise when lipomas become larger than 2 cm in size. Colonic lipomas are most often noted incidentally by colonoscopy. They may also be identified by abdominal imaging such as computed tomography or magnetic resonance imaging. We report a case of a sixty-one years old male who presented to our emergency room with a 6.7 cm × 6.3 cm soft tissue mucosal mass protruding transanally. The patient was stable with a benign abdominal examination. The mass was initially thought to be a rectal prolapse; however, a limited digital rectal exam was able to identify this as distinct from the anal canal. Since the mass was irreducible, it was elected to be resected under anesthesia. At surgery, manipulation of the mass identified that the lesion was pedunculated with a long and thickened stalk. A laparoscopic linear cutting stapler was used to resect the mass at its stalk. Pathology showed a polypoid submucosal lipoma of the colon with overlying ulceration and necrosis. We report this case to highlight this rare but possible presentation of colonic lipomas; an incarcerated, trans-anal mass with features suggesting rectal prolapse. Trans-anal resection is simple and effective treatment.     

直肠神经内分泌肿瘤的内镜下诊断与治疗

目的分析直肠神经内分泌肿瘤(R-NENs)的临床病理学特征,并探讨R-NENs内镜下的诊断特点及内镜下治疗的效果及安全性。方法回顾性分析2010年1月-2019年9月就诊于新疆医科大学第一附属医院并行常规结肠镜检查的76例R-NENs患者的临床资料,均经组织标本活检或手术切除瘤体病理检查明确诊断为R-NENs。结果肿瘤位于低位直肠段32例(42.11%),中段25例(32.89%),下段19例(25.00%)。36例行超声内镜(EUS)检查,其中27例EUS下诊断为R-NENs,2例诊断为间质瘤,6例诊断为脂肪瘤,1例诊断为平滑肌瘤,与病理结果诊断符合率达75.00%(27/36)。29例病例行内镜黏膜下剥离术(ESD),22例行内镜下黏膜切除术(EMR),20例行内镜经黏膜下隧道肿物剥离术(STER),2例行电凝电切术,3例因不同原因未通过上述内镜手术方式进行治疗。所有患者中69例行病理学检查及免疫组化检查,结果证实G1级最多见,共62例,占所有病例的81.58%(62/76)。结论R-NENs以男性多见,好发于中低位直肠段,其中G1级最为常见;EUS技术的成熟运用能够对病变性质及组织学起源进行较准确的判断,但也存在一定的误诊率,最终还应以病理结果为金标准;早期G1、G2级R-NENs经内镜治疗是安全有效的,并且能够提供较完整的病理学资料。     

超声内镜对结直肠黏膜下病变的诊断价值

目的探讨超声内镜(EUS)在结直肠黏膜下病变诊断和治疗中的作用。方法对结直肠黏膜下病变进行EUS检查。根据黏膜下病灶的起源层次,部分患者接受深挖活检、超声内镜引导下细针穿刺吸取活检术(EUS-FNA)、内镜下治疗或外科手术。回顾性分析EUS诊断结果与临床病理的相关性。结果 EUS检查的74例患者中,诊断神经内分泌肿瘤28例(均位于直肠);脂肪瘤15例(其中位于回盲部4例、横结肠1例、升结肠8例、乙状结肠2例);直肠间质瘤2例(固有肌层和黏膜肌层各1例);外压性改变14例(卵巢肿瘤9例,淋巴结2例,盆腔肿瘤3例);囊肿5例(横结肠4例、升结肠1例);气囊肿1例;乙状结肠子宫内膜异位3例;直肠周边恶性肿瘤侵犯4例;肠道淋巴瘤2例。所有病灶均接受深挖活检、EUS-FNA、内镜下治疗或外科手术。最终病理和EUS诊断符合率为68/74(91.9%),其中2例EUS考虑直肠类癌最后病理确诊为黏膜肌层来源的平滑肌瘤。1例考虑脂肪瘤最终确诊为肠道淋巴瘤。2例考虑直肠周边恶性肿瘤最终为炎性包块,1例考虑子宫内膜异位症最终诊断为直肠癌。结论 EUS能清晰地显示消化道各层结构,能清楚显示结直肠黏膜下病变的大小、起源及其与相邻结构的关系,并且能较精确地判断各种病变的性质,进而指导结直肠黏膜下病变的治疗。     

Saline-assisted endoscopic resection of rectal carcinoids: cap aspiration method versus simple snare resection

BACKGROUND AND STUDY AIMS: Complete resection of small carcinoid tumors of the rectum is difficult during endoscopic polypectomy, because these tumors are often located in the submucosal layer of the rectal wall. To completely remove these tumors, we have used aspiration lumpectomy. In this study, we evaluated its clinical usefulness in comparison with strip biopsy. PATIENTS AND METHODS: We performed strip biopsy (December 1996 through March 2000) or aspiration lumpectomy (April 2000 through February 2003) in a consecutive series of patients with rectal carcinoid tumor. Eight carcinoid tumors in eight patients were resected by strip biopsy, and eight tumors in eight patients were resected by aspiration lumpectomy. RESULTS: The rate of complete removal of carcinoid tumors with aspiration lumpectomy (100 %) was significantly higher (P < 0.05) than that with strip biopsy (37.5 %). CONCLUSIONS: Endoscopic resection with aspiration lumpectomy is a useful and safe method for resection of small carcinoid tumors of the rectum.     

原发性肛管直肠恶性黑色素瘤影像学诊断

目的探讨原发性肛管直肠恶性黑色素瘤（AMM）的CT和MRI诊断价值。方法回顾性分析经组织病理学证实的AMM7例,其中男3例,女4例。6例行CT检查,1例行MRI检查。结果AMM表现明显蕈伞型肿块充满肠腔不伴肠梗阻（n=5）,肠壁明显增厚（n=2）;3例伴肠周脂肪浸润,其中1例延伸至骶前间隙;5例伴淋巴结转移,其中1例淋巴结直径〉3cm。CT平扫示肿块呈稍低密度影,轻度强化2例、中度强化4例;AMM及其转移灶在MRIT1WI均呈高信号,T2WI为低信号。抑脂T1WI能更好的显示病灶范围及转移灶。结论肛门直肠部AMM可表现为腔内较大蕈伞型肿块,虽充满肠腔,但不伴肠梗阻,同样具转移淋巴结转移及明显肠周脂肪浸润。MRI对鉴别黑色素性AMM有提示价值。     

内镜黏膜下剥离术治疗直肠类癌的临床价值

目的探讨内镜下对直肠类癌的诊断与治疗的临床价值。方法肠镜发现直肠黏膜下肿块后进行微探头超声检查,对诊断为类癌的患者应用头端弯曲的针形切开刀进行内镜黏膜下剥离术（ESD）治疗：黏膜下注射生理盐水抬高病灶,使病灶与肌层分离;预切开病灶周围黏膜;剥离病变下方黏膜下层结缔组织,完整切除病灶。结果ESD手术时间（自黏膜下注射至完整剥离病变）25～55min;术中创面出现少量出血,均经电凝、氩离子血浆凝固和止血夹成功止血,不需再次肠镜下止血。术后全部经病理确诊,基底和切缘未见病变累及。1个月后肠镜复查,创面基本愈合。结论ESD是治疗直肠类癌的一种新方法,以往需要外科手术切除的肿瘤通过ESD可以达到同样的治疗效果。     

Endorectal sonography.

Endorectal sonography is a technique that has been developed recently to visualize the rectal wall and perirectal tissues with a high degree of clarity. Studies utilizing endorectal sonography in the preoperative staging of rectal carcinoma have reported an accuracy of between 67 and 92% in the visualization of the depth of tumor invasion in the rectal wall. This surpasses the accuracy reported for digital exam and other preoperative imaging methods such as CT and MRI. Perirectal lymphadenopathy is also well visualized by this method and guided biopsy of perirectal nodes has been reported. Precise preoperative staging of rectal carcinoma by endorectal sonography is an important technique that can: (1) improve surgical planning, (2) provide prognosis in nonsurgical candidates, and (3) select patients suitable for local excision therapy.     

A new model of rectal cancer with regional lymph node metastasis allowing in vivo evaluation by imaging biomarkers

Object

The work is aimed to develop a murine model of rectal cancer, which could be used to monitor lymph node metastasis development by magnetic resonance imaging (MRI) and optical imaging (OI) techniques.

Subjects and methods

Ht-29 cancer cells were directly injected into the submucosal layer of the rectum of athymic nude mice using trans-anal rectal cancer cell injection (TARCI). Thirty-six mice were inoculated with 10 × 10⁵ cells and five mice were treated with sterile phosphate buffer solution. One to 4 weeks after cell injection, tumor growth was evaluated in vivo using T2-weighted MRI at 4.7T. A further group of animal (n = 6) treated with ht-29_luc cells, with the same protocol, was monitored by optical imaging. In both groups, the presence of the primary tumor and of lymph nodes metastasis was confirmed by histology.

Results

In all animals, primary tumors were detectable by MRI, 1 week from TARCI. After 4 weeks primary tumors showed a mean longitudinal diameter of about 2 cm. All animals developed regional lymph node metastases. Others organs (e.g. lung or liver) were not affected. In fat-suppressed, T2-weighted MRI, lymph nodes appeared as small areas characterized by hyper-intense signal compared to muscle. OI permitted evaluation of the primary tumor growth in perineal region.

Conclusions

TARCI of ht-29 cells into the rectum of nude mice is a feasible way to obtain a easily reproducible model of regional lymph node metastases could be monitored by magnetic resonance and optical imaging techniques.     

内置水囊法超声诊断直肠和乙状结肠小肿瘤的价值

目的探讨内置水囊法超声诊断直肠和乙状结肠小肿瘤的价值。方法122例患者经直肠和乙状结肠内置水囊,并注入水300~500ml,在其充盈后进行超声检查。结果内置水囊下直肠和乙状结肠的小肿瘤为低回声,超声诊断结果与手术和病理对照,超声定位诊断符合率占84%,定性诊断符合率占88%。结论内置水囊法超声显像对直肠和乙状结肠小肿瘤有较高检出率,术前内置水囊法超声显像有一定价值。     

罕见直肠肛管恶性肿瘤的临床与影像学诊断

【目的】探讨罕见直肠肛管恶性肿瘤的临床影像学表现。【方法】报道罕见直肠肛管恶性肿瘤15例．包括非何杰金氏淋巴瘤3例．平滑肌肉瘤9例，脂肪肉瘤2例，恶性黑色素瘤1例．15例中12例做了CT检查，9例进行了气钡灌肠检查。【结果】气钡灌肠示该类肿瘤主要表现为直肠下端或肛管隆起性病变．肠腔明显狭窄．可伴不规则龛影．肉瘤常较大．而恶性淋巴瘤常表现多发。CT表现为直肠或肛管肠壁增厚或局部肿块，肉瘤肿块常较大，多伴更低密度坏死区。邻近组织或器官可受累及。【结论】罕见直肠与肛管恶性肿瘤常用影像学检查方法为气钡灌肠与CT．其表现仅具有相对性特征。     

超声内镜及内镜黏膜下剥离术对直肠类癌的诊疗价值

目的探讨超声内镜(EUS)对直肠类癌治疗的指导价值,及内镜黏膜下剥离术(ESD)对直肠类癌治疗的安全性及有效性。方法对临床考虑直肠类癌的患者进行EUS检查,根据EUS结果选择适合的治疗方案。结果 45例术前病理确诊的类癌病例,42例经ESD治疗,2例累及固有肌层及1例浸透浆膜层并伴有周围淋巴结转移者,经外科手术治疗。结论 EUS能够明确直肠类癌的大小、浸润深度、有无周围淋巴结肿大,对其治疗有较高的指导价值。对于小于20 mm直肠类癌,ESD是一种安全、有效的方法。     

直肠类癌33例内镜治疗体会及文献回顾

目的总结直肠类癌的内镜下治疗方法与各自的优势。方法对2009年1月至2012年12月33例直肠类癌行内镜下治疗患者的临床资料进行回顾性分析,所有患者根据情况分别选择内镜下黏膜切除术（EMR）或经内镜黏膜下剥离术（ESD）治疗,总结其内镜下表现特点及治疗情况。结果 33例直肠类癌中,14例行EMR治疗,19例行ESD治疗。病灶位于直肠距肛门齿状线4～15cm,切除病灶直径0.3～1.5 cm。7例行EMR中途改行ESD,2例EMR术后肿瘤残留追加外科手术。病理学分析ESD组完整切除率（100%）较EMR组完整切除率（85.7%）有所提高,但差异无统计学意义（P〉0.05）。两组均未出现大出血、穿孔等并发症。结论相比EMR,ESD可能有利于实现直肠类癌病变的完整切除,减少复发,且安全性不亚于EMR。对于较小的直肠类癌,ESD不失为一种有效的治疗手段。     

Endoluminal MR imaging of diseases of the anus and rectum

Endoluminal MRI of the rectum and anus was introduced in the first half of this decade to overcome the limitations of endoluminal sonography and body coil MRI. Endoluminal MRI is the imaging method of choice for fecal incontinence and anal tumors, whereas it is a competitive imaging method to phased array coil MRI in patients with perianal fistulas or rectal tumor. The purpose of this article is to describe the technique and major indications of endoluminal MR imaging of the anus and rectum.     

New trial of endoscopic treatment for gastric submucosal tumors

Recently conservative treatment of gastric submucosal tumors is increasing in spite of the absence of definite criteria for histological diagnosis. We have developed a new method of endoscopical treatment of gastric submucosal tumors that have submucosographically intraluminal Pattern I or II, or partly intramural Pattern III. For such tumors with a maximum diameter less than 5 cm, Ist step: partial resection is carried out with the use of high-frequency electric currents, IInd step: for the residual tumor tissue, in vivo tissue solidification is undertaken by local injection of absolute ethanol to induce necrotic exfoliation of the tumor tissue and to prevent of hemorrhage.     

Section 6. Digestive organs: Minimally invasive surgery for carcinoid tumors in the rectum

Most carcinoid tumors of the rectum are confined to the submucosa with a size less than 1–2 cm and are usually suitable for local excision, as metastasis to the regional nodes is limited. Endoscopic excision of carcinoid tumors has been performed for this entity as a least invasive method but incomplete resection and/or unclear surgical margin and curability have been reported to occur in 24–42% of cases because of a limited resection up to the submucosal layer and burn effect. Transanal local excision has often been applied for rectal carcinoid tumor as a least invasive method among local excision procedures to accomplish full thickness excision for determining the curability. However, it is often difficult to obtain free access with a sufficient surgical field by the conventional method. Transanal endoscopic microsurgery (TEM) has appeared as a useful option to access a high tumor with fine visibility but special caution has to be taken for tumors sited above the peritoneal reflection. To facilitate full thickness excision even for high tumors, novel local excisional technique called minimally invasive transanal surgery (MITAS) has been developed and used for local removal of carcinoid tumors in the rectum. A specially designed anal retractor connected to the Octopus retractor holder with several novel techniques facilitated excisional procedures around the anus with a sufficient fixed surgical field and an ENDO-stapler allowed the simultaneous excision and anastomosis to be performed. The technique facilitated total excisional biopsy with less operative time and blood loss, and no mobility or mortality in 12 patients with rectal carcinoid tumors.     

The role of MR imaging in soft tissue tumor evaluation: perspective of the orthopedic oncologist and musculoskeletal pathologist

Soft tissue masses are common in both children and adults. Clinicians must evaluate patients carefully to avoid management errors. The most effective management decisions are made when a working group composed of clinicians, radiologists, and pathologists participates in the interpretation of the imaging studies. Plain-film radiographs and MR imaging scans are the two main imaging modalities used in patients with soft tissue masses. The working group assimilates the clinical and radiographic data to determine if they can identify the nature of the soft tissue mass. When the group can assign a definitive diagnosis, the lesion is designated as a determinate lesion. Determinate lesions include lipomas, ganglions, hemangiomas, neurofibromas, diabetic myonecrosis, muscle tears, myositis ossificans (heterotopic ossification), and pigmented villonodular synovitis. When the process cannot be identified, the lesion is classified as indeterminate. All soft tissue sarcomas are indeterminate lesions. Many benign lesions are also indeterminate. Common examples include schwannomas, myxomas, and giant cell tumor of tendon sheath. Based on the clinical and radiologic features, these diagnoses may be suspected, but because of the inability to distinguish them from sarcomas based on the MR imaging features, they are usually classified as indeterminate. When lesions are judged to be determinate, observation or excisional biopsy are the two major treatment choices. When lesions cannot be identified on the imaging studies, incisional or needle biopsy is performed to establish a diagnosis. Once a diagnosis is made, the proper management choice can be selected. Inappropriate excisional biopsy is the major treatment error in the management of soft tissue tumors. When a high-grade soft tissue sarcoma is resected with multiple positive margins, the risk of local failure after definitive resection is much higher than if the patient had been treated initially with only a needle or incisional biopsy. Also, if a major complication, such as an infection, a major wound-healing problem, or contamination of the major neurovascular structures, occurs at the time of incisional biopsy, amputation of the limb may be necessary. Inappropriate excisional biopsy can occur when a surgeon is not familiar with the features of sarcomas or when a radiologist mistakenly interprets the signal features as a benign lesion.     

Intra-abdominal desmoid-type fibromatosis successfully resected using laparoscopic fluorescence imaging with indocyanine green after intersphincteric resection for rectal cancer

Successful resection of intra-abdominal tumors using indocyanine green (ICG) fluorescence imaging has not been reported. Here, we report a rare case of an intra-abdominal desmoid-type fibromatosis successfully resected using this technique after intersphincteric resection (ISR) for rectal cancer. One year after ISR for rectal cancer in a 47-year-old man, computed tomography showed a 50-mm intra-abdominal tumor near the left common iliac vein. Surgical resection was performed. The tumor was located in the mesentery of the remnant rectum after ISR. ICG fluorescence imaging confirmed the blood supply to the mesentery of the distal remnant rectum after tumor excision. The anal canal was successfully preserved without creating a permanent colostomy. The tumor was safely resected with resection margins, diagnosed as desmoid-type fibromatosis. No tumor recurrence was observed 6 months post-resection. This was the first case report to demonstrate the utility of this technique for an intra-abdominal tumor resection.     

Endoscopic ultrasound of the upper gastrointestinal tract

Endoscopic ultrasound (EUS) is an evolving technique used by gastroenterologists to examine lesions that are located either within or adjacent to the walls of the upper gastrointestinal (GI) tract; this topic is relatively unknown to most radiologists. Proper use of this modality is benefited by a cooperative effort between gastroenterologists and radiologists specializing in ultrasound and cross-sectional imaging. This article informs radiologists of the applications of this procedure. Most patients are examined with EUS after a biopsy of a mucosal tumor has been performed. A smaller number are performed to evaluate submucosal masses or when pancreatic disease is suspected but not diagnosed. The examinations can be performed either with dedicated flexible echoendoscopes or with catheter-based probes passed through a conventional endoscope. The exact location of abnormalities associated with the upper GI tract can be observed. Known anatomic landmarks are sought. Abnormalities of structures outside the upper GI tract will occasionally be found during these examinations. The specific layers of the walls of the gut are examined, and the T and N-classification of upper GI tumors can be determined accurately. The performance of an EUS examination requires advanced skills, and in many medical centers, it is the imaging modality of choice to stage cancers, to evaluate submucosal masses, and to investigate both malignant and benign pancreaticobiliary disease. Endoscopic ultrasound is sensitive but not specific, and biopsy is necessary to establish a diagnosis. Therapeutic applications of EUS are evolving. Specialized applications with catheter-based probes are also being developed.     

Endorectal color and duplex imaging of the normal rectal wall and rectal masses.

This study investigates the ability of endorectal ultrasonography aided by color flow and pulse wave Doppler techniques to identify submucosal arterial plexuses of the normal rectal wall and to detect vessels supplying rectal wall masses. Color flow and pulsed wave Doppler analysis of 62 normal submucosal arterial plexuses and vessels feeding rectal wall masses (one rectal endometriosis and seven rectal cancers) was performed. The color signals from normal submucosal arterial plexuses and the one case of rectal endometriosis were judged to be sparse or decreased in comparison to color signals from rectal cancers. The median and mean P1 values for normal submucosal arterial plexuses were significantly greater than those for the central feeding vessels or small peripheral vessels within rectal masses. Our experience with color and duplex endorectal ultrasonography suggests that different vascular structures exist in normal persons compared to those in rectal wall masses. Pathologically, rectal cancers possess vessels with and without a smooth muscle layer, which may produce the high and low resistance signals identified by pulse Doppler.