Liver metastases of a neuroendocrine tumor arising from a tailgut cyst treated with interventional locoregional therapies: a case report and review of the literature on recurrent cases.

A tailgut cyst is a rare, developmental cyst occurring in the presacral space. Although primarily benign, malignant transformation is a possible complication. Herein, we report a case of liver metastases after resection of a neuroendocrine tumor (NET) arising from a tailgut cyst. A 53-year-old woman underwent surgery for a presacral cystic lesion with nodules in the cyst wall. The tumor was diagnosed as a Grade 2 NET arising from a tailgut cyst. Thirty-eight months after surgery, multiple liver metastases were identified. The liver metastases were controlled with transcatheter arterial embolization and ablation therapy. The patient has survived for 51 months after the recurrence. Several NETs derived from tailgut cysts have been previously reported. According to our literature review, the proportion of Grade 2 tumors in NETs derived from tailgut cysts was 38.5%, and four of the 5 cases of Grade 2 NETs (80%) relapsed, while all eight cases of Grade 1 NETs did not relapse. Grade 2 NET may be a high-risk group for recurrence in NETs arising from tailgut cysts. The percentage of Grade 2 NETs in tailgut cysts was higher than that of rectal NETs, but lower than that of midgut NETs. To the best of our knowledge, this is the first case of liver metastases of a neuroendocrine tumor arising from a tailgut cyst that was treated with interventional locoregional therapies, and the first report to describe about the degree of malignancy of neuroendocrine tumors originating from tailgut cysts in terms of the percentage of Grade 2 NETs.

A case of Cronkhite-Canada syndrome with repeated linked color imaging observation of the subepithelial capillary network in the colon.

Cronkhite-Canada syndrome (CCS) is a non-hereditary disorder characterized by non-neoplastic gastrointestinal polyposis and ectodermal changes. While corticosteroids are considered effective, some cases are refractory. A 48-year-old woman presented with diarrhea, anorexia, and epigastralgia lasting for 3 months. She suffered from alopecia and nail dystrophy. Gastrointestinal endoscopy with histological examination confirmed non-neoplastic polyposis from the stomach to the rectum, confirming the diagnosis of CCS. Linked color imaging (LCI) with magnified endoscopy revealed a ribbon-like proliferation of capillaries surrounding the pits in the colonic mucosa. Histologically, the polyps had dilated glands, edematous stroma with inflammatory cell infiltrates and increased capillaries just beneath the epithelium. Immunohistochemical examination confirmed the expression of vascular endothelial growth factor (VEGF), mainly in the superficial epithelial and crypt cells. Steroid therapy was ineffective, and concomitant infliximab therapy provided symptomatic relief. Although symptoms rapidly improved with combination therapy, capillary hyperplasia and slight inflammation persisted in the colon mucosa after polyp resolution. Withdrawal of steroid treatment resulted in flare-ups of symptoms and polyps. Repeated magnified observations at LCI during post-relapse retreatment clearly captured the resolution process of both neovascularization and inflammation. Once the capillary hyperplasia and inflammation subsided, the steroid could be tapered off without relapse. To our knowledge, this is the first report describing the involvement of VEGF-induced angiogenesis and LCI findings in CCS; LCI observations are useful not only in the active phase of CCS, but also in determining subtle capillary hyperplasia and residual inflammation in remission, which may be an indicator of continued treatment.

Serrated polyposis syndrome with multiple inverted lesions in the colon: Case report and elucidation of morphogenetic mechanism.

A 70-year-old man underwent surveillance colonoscopy following surgery for occlusive sigmoid colon cancer. The procedure revealed nine sessile serrated lesions (SSLs), including three inverted lesions. Endoscopic and surgical resections were performed. All nine lesions were confirmed pathologically as SSL, and the patient was diagnosed with serrated polyposis syndrome (SPS). Three inverted SSLs (iSSLs) showed endophytic growth without epithelial misplacement. Crypt analysis revealed that iSSL crypts were wider at the bottom than the opening, roughly resembling a frustoconical shape. Our results suggest that a horizontal arrangement of frustoconical crypts leads to hemispherical deformation of the muscularis mucosa, forming an inverted shape. This is the first report to reveal the morphogenesis of iSSLs from the shape of the crypt.

Acute superior mesenteric artery occlusion associated with COVID-19 pneumonia: a case report.

BACKGROUND: The novel 2019 coronavirus disease (COVID-19), which is caused by infection with the severe acute respiratory syndrome coronavirus 2, has spread rapidly around the world and has caused many deaths. COVID-19 involves a systemic hypercoagulable state and arterial/venous thrombosis which induces unfavorable prognosis. Herein, we present a first case in East Asia where an acute superior mesenteric artery (SMA) occlusion associated with COVID-19 pneumonia was successfully treated by surgical intervention. CASE PRESENTATION: A 70-year-old man presented to his local physician with a 3-day history of cough and diarrhea. A real-time reverse transcriptase-polymerase chain reaction test showed positive for COVID-19, and he was admitted to the source hospital with the diagnosis of moderate COVID-19 pneumonia. Eight days later, acute onset of severe abdominal pain appeared with worsening respiratory condition. Contrast CT showed that bilateral lower lobe/middle lobe and lingula ground glass opacification with distribution suggestive of COVID-19 pneumonia and right renal infarction. In addition, it demonstrated SMA occlusion with intestinal ischemia suggesting extensive necrosis from the jejunum to the transverse colon. The patient underwent an emergency exploratory laparotomy with implementing institutional COVID-19 precaution guideline. Upon exploration, the intestine from jejunum at 100 cm from Treitz ligament to middle of transverse colon appeared necrotic. Necrotic bowel resection was performed with constructing jejunostomy and transverse colon mucous fistula. We performed second surgery to close the jejunostomy and transverse colon mucous fistula with end-to-end anastomosis on postoperative day 22. The postoperative course was uneventful and he moved to another hospital for rehabilitation to improve activities of daily living (ADLs) on postoperative day 45. As of 6 months after the surgery, his ADLs have completely improved and he has returned to social life without any intravenous nutritional supports. CONCLUSIONS: Intensive treatment including surgical procedures allowed the patient with SMA occlusion in COVID-19 pneumonia to return to social life with completely independent ADLs. Although treatment for COVID-19 involves many challenges, including securing medical resources and controlling the spread of infection, when severe abdominal pain occurs in patients with COVID-19, physicians should consider SMA occlusion and treat promptly for life-saving from this deadly combination.

Effect of preoperative asymptomatic renal dysfunction on the clinical course after colectomy for colon cancer.

PURPOSE: To evaluate the effect of mild renal dysfunction on the clinical course after colectomy in patients with colon cancer. METHODS: The subjects of this retrospective study were 263 patients who underwent surgical resection for colon cancer at our hospital between 2011 and 2015. Renal function was assessed based on preoperative estimated glomerular filtration rate (eGFR) values. Patients were divided into groups based on their eGFR value of 55 ml/min/1.73 m2. The Mann-Whitney U test, chi-square or Fisher exact test, and log-rank test were used in the data analysis. RESULTS: There were 59 patients (22.4%) in the low eGFR group and 204 patients in the normal eGFR group. There were differences between the groups in age, comorbidities, and the levels of hemoglobin, albumin, and serum creatinine. The overall postoperative complication rate, frequency of severe complications, and length of stay were significantly higher in the low eGFR group than in the normal eGFR group. Multivariate analysis revealed that low eGFR was the only independent risk factor for severe complications (Clavien-Dindo classification III/IV). There were no differences in survival between the groups. CONCLUSION: Preoperative asymptomatic renal dysfunction may be correlated with the development of postoperative complications and a possible significant risk factor for severe complications after colon cancer surgery.

In vitro analysis of exfoliated tumor cells in intraluminal lavage samples after colorectal endoscopic submucosal dissection.

PURPOSE: Colorectal endoscopic submucosal dissection (ESD) produces exfoliated tumor cells that occasionally cause local recurrence. However, the biological characteristics of these tumor cells have not been clarified. The aim of this study was to clarify the genetic background and viability of exfoliated tumor cells in colorectal ESDs, as well as possible method for their elimination. METHODS: Post-ESD intraluminal lavage samples from 19 patients who underwent colorectal ESDs were collected. In four patients with adenocarcinoma, gene mutations in the primary tumors and exfoliated cells in lavage samples were analyzed using a next-generation sequencer (NGS). In 15 patients with adenoma or adenocarcinoma, the viability of exfoliated cells and the cell-killing effect of povidone-iodine on exfoliated cells were evaluated. RESULTS: The analysis using a NGS demonstrated that tumors targeted for ESD had already acquired mutations in many genes involved in cell proliferation, angiogenesis, and invasions. Furthermore, gene mutations between the exfoliated tumor cells and tumors resected by ESDs showed a 92 to 100% concordance. The median viable cell counts and the median viability of exfoliated cells in intraluminal lavage samples after ESDs were 4.9 × 105 cells/mL and 24%, respectively. The viability of the exfoliated cells did not decrease even 12 h after ESD. However, contact with 2.0% povidone-iodine solution reduced both viable cell counts and viability, significantly. CONCLUSION: A large number of tumor cells exfoliated during colorectal ESDs had acquired survival-favorable gene mutations and could survive for some time. Therefore, a lavage using a solution of 2.0% povidone-iodine may be effective against such cells. TRIAL REGISTRATION: The prospective study registered 1317, and the retrospective study registered 2729. The prospective study approved on June 20, 2016, and the retrospective study approved on October 6, 2020.

Endoscopic Features of Postoperative Anastomotic Lesions in Patients with Crohn's Disease Compared with Right-side Colon Cancer: Are Anastomotic Linear Superficial Ulcers Recurrent in Crohn's Disease?

OBJECTIVES: Many patients have endoscopic evidence of recurrent Crohn's disease (CD) 1 year after intestinal resection, and endoscopic lesions predict future clinical recurrence. The aim of this study was to describe some anastomotic lesions including changes in endoscopic features in CD patients and to discuss recurrence. We also compared anastomotic lesions in CD patients and in right-side colon cancer (rt-CC) patients. METHODS: We enrolled patients with CD and rt-CC who underwent surgical resection between 2008 and 2014. Eleven CD patients underwent postoperative endoscopy at least twice, with the first time being from 6 months to 1 year after surgery and the second time being from 2 to 3 years after surgery. Eighty-six patients with rt-CC underwent postoperative endoscopy after approximately one year. RESULTS: A total of 90.9% of CD patients had postoperative lesions around the anastomosis at the first postoperative ileocolonoscopy, which was markedly higher than that in rt-CC patients (3.5%, p<0.001). Many of these lesions in CD required enhanced treatment. However, linear superficial ulcers at the anastomotic line at the first ileocolonoscopy did not worsen with the same treatment (18.1%). CONCLUSIONS: Postoperative anastomotic lesions were detected at a higher rate in CD cases than that in rt-CC cases. Many anastomotic lesions were recognized as recurrent disease and required enhanced treatment, whereas linear superficial ulcers did not require treatment changes. Therefore, linear superficial ulcers might not be recurrent disease. As this issue is related to recurrence, it should be further explored with the accumulation of more cases in a multicenter analysis.

The middle rectal artery detected by contrast-enhanced magnetic resonance imaging predicts lateral lymph node metastasis in lower rectal cancer.

PURPOSE: Lateral lymph node (LLN) metastasis is one of the leading causes of local recurrence in patients with lower rectal cancer. Unfortunately, no diagnostic biomarkers are currently available that can predict LLN metastasis preoperatively. Accordingly, we investigated the relationship between the middle rectal artery (MRA) identified by contrast-enhanced magnetic resonance imaging (ceMRI) and LLN metastases. METHODS: Data from 102 patients with lower rectal cancer who underwent surgery, and were evaluated by preoperative ceMRI, between 2008 and 2016 were reviewed retrospectively. Two expert radiologists evaluated the MRA findings. The diagnostic performance of MRA for LLN metastasis was evaluated by a multivariate analysis with conventional clinicopathological factors. RESULTS: The MRA was detected in 67 patients (65.7%), including 32 (31.4%) with bilateral MRA and 35 (34.3%) with unilateral MRA. The tumor size, presence of the MRA, and clinical LLN status were significantly correlated with LLN metastasis. A multivariate analysis demonstrated that the presence of MRA (P = 0.045) and clinical LLN status (P = 0.001) were independent predictive factors for LLN metastasis. Furthermore, the sensitivity and negative predictive value of MRA for LLN metastasis were 95% and 97.1%, respectively. CONCLUSION: We successfully demonstrated that MRAs could be clearly detected by ceMRI, and the presence of MRA robustly predicted LLN metastasis in patients with lower rectal cancer, highlighting its clinical significance in the selection of more appropriate treatment strategies. TRIAL REGISTRATION: Trial registration number: retrospectively registered 2126 Trial registration date of registration: August 23, 2019.

The Prognosis and Recurrence Pattern of Right- and Left-Sided Colon Cancer in Stage II, Stage III, and Liver Metastasis After Curative Resection.

PURPOSE: Primary tumor location of colon cancer has been reported to affect the prognosis after curative resection. However, some reports suggested the impact was varied by tumor stage. This study analyzed the prognostic impact of the sidedness of colon cancer in stages II, III, and liver metastasis after curative resection using propensity-matched analysis. METHODS: Right-sided colon cancer was defined as a tumor located from cecum to splenic flexure, while any more distal colon cancer was defined as left-sided colon cancer. Patients who underwent curative resection at Nara Medical University hospital between 2000 and 2016 were analyzed. RESULTS: There were 110 patients with stage II, 100 patients with stage III, and 106 patients with liver metastasis. After propensity matching, 28 pairs with stage II and 32 pairs with stage III were identified. In the patients with stage II, overall survival (OS) and recurrence-free survival (RFS) were not significantly different for right- and left-sided colon cancers. In the patients with stage III, OS and RFS were significantly worse in right-sided colon cancer. In those with liver metastasis, OS of right-sided colon cancer was significantly worse than left-sided disease, while RFS was similar. Regarding metachronous liver metastasis, the difference was observed only in the patients whose primary colon cancer was stage III. In each stage, significantly higher rate of peritoneal recurrence was found in those with right-sided colon cancer. CONCLUSION: Sidedness of colon cancer had a significant and varied prognostic impact in patients with stage II, III, and liver metastasis after curative resection.

A combination of subcuticular sutures and subcutaneous closed-suction drainage reduces the risk of incisional surgical site infection in loop ileostomy closure.

PURPOSE: The purpose of this study was to evaluate the effectiveness of a wound closure method using a combination of subcuticular sutures and subcutaneous closed-suction drainage (SS closure) for preventing incisional surgical site infection (SSI) in loop ileostomy closure. METHODS: A total of 178 consecutive patients who underwent loop ileostomy closure at Nara Medical University Hospital between 2004 and 2018 were retrospectively assessed. The patients were divided into 2 groups: the conventional skin closure (CC) group from 2004 to 2009 (75 patients) and the SS closure (SS) group from 2010 to 2018 (103 patients). The incidence of incisional SSI was compared between the two groups, and the factors associated with incisional SSI were examined by univariate and multivariate analyses. RESULTS: Incisional SSI occurred in 7 cases (9.3%) in the CC group but was significantly reduced to only 1 case (0.9%) in the SS group (p = 0.034). In the univariate analysis, the hemoglobin levels, serum creatinine levels, and SS closure were associated with incisional SSI. SS closure was the only independent preventive factor for incisional SSI according to the multivariate analysis (hazard ratio = 0.24, p = 0.011). CONCLUSION: The combination of subcuticular sutures and subcutaneous closed-suction drainage may be a promising way of preventing incisional SSI in loop ileostomy closure.

A case of an enlarged rectal adenoma while achieving a clinical complete response with chemotherapy for advanced rectal cancer.

The effect of chemotherapeutic agents on concomitant colorectal adenomas in patients with advanced colorectal cancer is not clear. We report a case of an enlarged rectal adenoma while achieving a clinical complete response with chemotherapy for an advanced rectal adenocarcinoma. A 78-year-old man was referred to our hospital for evaluation of bloody stools. The clinical diagnosis was an advanced lower rectal adenocarcinoma with para-aortic lymph node metastases, and a sessile polyp on the proximal aspect of the rectal tumor. The rectal adenocarcinoma was treated with chemotherapy, including 1 cycle of capecitabin plus oxaliplatin (CapeOX), 22 cycles of tegafur/gimeracil/oteracil (S-1) plus irinotecan (IRIS), and 1 cycle of tegafur (UFT) plus calcium folinate (LV). One year after the last course of chemotherapy, colonoscopy showed a scar without visible rectal tumor; CT imaging confirmed no para-aortic lymphadenopathy. The patient had a clinical complete response to chemotherapy. In contrast, the polyp increased in size. The polyp was removed by endoscopic mucosal resection (EMR). The pathologic evaluation showed a well-differentiated tubular adenocarcinoma with adenoma localized in the mucosa. No recurrence of the advanced adenocarcinoma or intramucosal adenocarcinoma with adenoma occurred for 2 years after EMR. This case indicates the importance of careful surveillance for synchronous adenomas, even in patients with advanced colorectal cancer.

A detailed comparison between the endoscopic images using blue laser imaging and three-dimensional reconstructed pathological images of colonic lesions.

Blue laser/light imaging (BLI) is an image-enhanced endoscopy (IEE) technique that can provide an accurate diagnosis by closely observing the surface structure of various colonic lesions. However, complete correspondence between endoscopic images and pathological images has not been demonstrated. The aim of this study was to accurately compare endoscopic images and the pathological images using a three-dimensionally (3D) reconstructed pathological model. Continuous thin layer sections were prepared from colonic tissue specimens and immunohistochemically stained for CD34 and CAM5.2. Three-dimensional reconstructed images were created by superimposing immunohistochemically stained pathological images. The endoscopic image with magnifying BLI was compared with the top view of the 3D reconstructed image to identify any one-to-one correspondence between the endoscopic images and histopathological images using the gland orifices and microvessels as a guide. Using 3D reconstructed pathological images, we were able to identify the location on the endoscope image in cases of colonic adenocarcinoma, adenoma and normal mucosa. As a result, the horizontal plane of the endoscopic image and the vertical plane of the 2D pathological specimen were able to be compared, and we successfully determined the visible blood vessel depth and performed a detailed evaluation on magnifying BLI. Examples are as follows: (1) The median vasculature depth from the mucosal surface that could be recognized as vasculature on magnifying BLI was 29.4 µm. The median depth of unrecognizable vessels on magnifying BLI was 218.8 µm, which was significantly deeper than recognizable vessels. (2) Some brownish structures were suggested to potentially be not only dense vessels, vessel expansions, corrupted vessels but also bleeding or extravasation of erythrocytes. Overall, we demonstrated a new approach to matching endoscopic images and pathological findings using a 3D-reconstructed pathological model immunohistochemically stained for CD34 and CAM5.2. This approach may increase the overall understanding of endoscopic images and positively contribute to making more accurate endoscopic diagnoses.

Characteristics of Five-year Survivors After Liver Resection for Colorectal Liver Metastases in Modern Chemotherapy.

BACKGROUND/AIM: The aim of this study was to evaluate whether modern chemotherapy has changed characteristics of actual five-year survivors after liver resection for colorectal liver metastasis (CRLM). PATIENTS AND METHODS: The records of 210 patients, who underwent curative liver resection for CRLM at our institution between January 1990 and May 2014, were reviewed. The patients treated before 2004 when modern chemotherapy was not introduced were compared with the patients treated after 2005. RESULTS: Actual five-year survivor rates were significantly higher after 2005 (33.3% vs. 49.0%, p=0.022). Preoperative characteristics of actual five-year survivors were not different. The median survival time after non-resectable recurrence was significantly longer after 2005 (20.3 vs. 8.7 months, p=0.002). The proportion of 5-year survivors with recurrent site was significantly higher after 2005 (34.0% vs. 10.5%, p=0.019). CONCLUSION: Actual five-year survivors have increased by modern chemotherapy. However, approximately one-third of them were not cured.

Learning curve for laparoscopic transabdominal preperitoneal repair: A single-surgeon experience of consecutive 105 procedures.

INTRODUCTION: Based on previously published papers, the learning curve for laparoscopic groin hernia repair is controversial. The purpose of the present study was to evaluate the learning curve for laparoscopic surgery for groin hernia in a local hospital setting. METHOD: We analyzed 100 consecutive cases of laparoscopic transabdominal preperitoneal repair performed by a single surgeon at a single facility from April 2013 to December 2015. The total operative time was divided into three parts: (a) preparing the peritoneal flap, (b) unfolding the mesh, and (c) suturing the peritoneum. A cumulative sum method for the total operative time and duration of the three parts was used to determine the learning curve. RESULTS: The learning curve was overcome after 75 cases based on cumulative sum analysis of the total operative time. The cumulative sum analysis of the times to unfold mesh and to suture the peritoneum indicated that the learning curve was overcome after 22 and 32 cases, respectively. The learning curve for preparing the peritoneal space was correlated with that for the entire procedure. No cases of recurrence were encountered. CONCLUSION: At least 75 cases were needed to overcome the learning curve for laparoscopic transabdominal preperitoneal repair.

Anorectal Cancer in Crohn's Disease Has a Poor Prognosis Due to its Advanced Stage and Aggressive Histological Features: a Systematic Literature Review of Japanese Patients.

BACKGROUND: Patients with Crohn's disease (CD) are generally known to be at an increased risk of cancer. The anorectal area is the most frequent cancer site in Japanese CD patients. However, the risks are not well defined. The aim of this study was to clarify the clinicopathological characteristics of Japanese CD-associated anorectal carcinoma patients and to explore screening methods for the detection of cancer at earlier stages. METHODS: A systematic review of case series and reports of Japanese CD-associated anorectal cancer patients published between 1983 and 2016 was conducted. RESULT: There were 144 cases of cancer arising from anorectal lesions of CD. The median duration from the onset of CD to the cancer diagnosis was approximately 17 (0-39) years. The most prevalent histological type of cancer was mucinous carcinoma (49.3%), and 82.1% of patients were over T3 invasion. There were only 15.6% cases with early stage disease. A total of 82% patients had enhanced symptoms, whereas 56.3% of the early cancer cases had no symptomatic changes. Approximately 90% of cases were diagnosed preoperatively, and almost all early cancer patients were diagnosed with colonoscopy. The 5-year overall survival rate was 35.8%. CONCLUSION: CD-associated anorectal carcinoma had a poor prognosis due to the advanced stage of the cases and aggressive histological features. As earlier-stage cancer is associated with a better prognosis than advanced stage disease, and it is also typically diagnosed by colonoscopy, surveillance colonoscopy may therefore help to improve the prognosis in cases without any symptomatic changes.

Long-term survival after adrenal metastasectomy from colorectal cancer: a report of two cases.

BACKGROUND: Solitary adrenal metastasis from colorectal cancer is rare. Adrenal metastasis is usually detected with synchronous multiple metastases in other organs and is, therefore, considered to be unsuitable for surgical resection. The long-term outcomes of patients with solitary adrenal metastasectomy from colorectal cancer have been reported; however, the survival advantage has not been established. We herein report two cases of curative adrenal resection in patients with solitary adrenal metastasis from colorectal cancer who achieved long-term survival of > 9 years without recurrence after surgical resection. CASE PRESENTATION: The first case involved a 71-year-old man who underwent abdominoperineal rectal resection for rectal cancer. Preoperative CT revealed a mass in the right adrenal, which was growing after surgery. After chemotherapy the adrenal mass decreased in size, and adrenalectomy was performed at 8 months after the first surgery. A pathological examination confirmed metastasis from rectal cancer. The patient received adjuvant chemotherapy and is currently alive without recurrence at 9 years after the adrenalectomy. The second case involved a 53-year-old man who underwent sigmoidectomy for sigmoid colon cancer. Four years later, lobectomy was performed for isolated lung metastasis. Twenty months later, PET-CT revealed solitary metastasis in the left adrenal gland and adrenalectomy was performed. A histopathological examination revealed metastatic adenocarcinoma of sigmoid cancer. Postoperative chemotherapy was administered after adrenalectomy and the patient is currently alive and apparently disease-free at more than 9 years after undergoing adrenal metastasectomy. CONCLUSION: Curative resection for solitary adrenal metastasis from colorectal cancer may be beneficial for survival.

Anal gland adenocarcinoma in situ with pagetoid spread: a case report.

BACKGROUND: Anal gland carcinoma with perianal Paget's disease is rare, and anal gland carcinoma in situ is extremely rare. No cases of anal gland carcinoma in situ with pagetoid spread have been previously reported. CASE PRESENTATION: Physical examination in a 75-year-old woman revealed an erythematous, inflamed, perianal skin lesion. Neither colposcopy, cystoscopy, colonoscopy, computed tomography, nor magnetic resonance imaging showed evidence of malignant genitourinary or gastrointestinal lesions. Histopathological examination of a biopsy specimen showed many Paget's cells in the perianal skin lesion and no malignant cells in the rectal or vaginal mucosa. Therefore, primary extramammary Paget's disease of the anogenital region was suspected, and we performed anus-preserving wide local excision. However, immunohistochemistry revealed a diagnosis of secondary extramammary Paget's disease due to adenocarcinoma arising from the anal gland. We therefore proceeded with a radical operation. Histopathological examination showed no residual cancer cells. The final diagnosis was anal gland adenocarcinoma in situ with pagetoid spread in the perianal skin. CONCLUSIONS: This is the first case report of anal gland adenocarcinoma in situ with pagetoid spread. We recommend immunohistochemical analysis of biopsy and locally resected specimens to obtain an accurate diagnosis and determine the appropriate treatment when there is no visible tumor.