Primary malignant melanoma of the right colon

The small and large intestines are the most common sites for metastases from cutaneous malignant melanoma. However, primary melanomas in these sites are exceedingly rare. There are several case reports of patients with primary melanoma of the small bowel, but finding of a solitary primary melanoma in the colon is exceedingly rare. We describe a patient that was operated on for bowel obstruction due to colonic intussusception resulting from a right colonic tumor. Histopathological examination confirmed a diagnosis of malignant melanoma. A thorough postoperative investigation did not reveal a primary lesion in any other site. Two years after surgery, there was no evidence for recurrent disease. The treatment and prognosis of metastatic and primary melanoma of the gastrointestinal tract is discussed as well as the embryonic base for development of primary malignant melanoma of the intestine. Primary malignant melanoma of the intestine is an extremely rare lesion that may arise in the large bowel as well. It must be differentiated from other intestinal tumors and mandates a thorough investigation to rule out the possibility of being a metastasis from another more common primary site.     

Primary small bowel melanoma. A case report and a review of the literature

Primary malignant melanoma originating from the small intestine is extremely rare. Only a limited number of cases are described in the literature. Most commonly small intestine is affected by metastatic tumors from other primary lesions. We present a case of a 68-years old male diagnosed with primary malignant melanoma as an ulcerated and bleeding mass in the jejunum - located 40 cm away from the Treitz band. In our case the diagnosis was confirmed at laparotomy and enterectomy. Histology revealed a neoplastic infiltration involving the entire intestinal mucosa, with atypia of neoplastic cells and immunoreactivity to HMB45(+), Melan A(+) and S100(+), confirming the diagnosis of melanoma. There was not revealed a primary lesion in the skin, eye, anus, rectum or in other location by the post-operative investigation. An eleven-month close follow-up has not revealed any metastasis. Therefore a definitive diagnosis of primary malignant melanoma was set.     

Primary Malignant Melanoma of the Small Intestine: a Case Report

The small intestine is the most common site of gastro-intestinal metastasis from cutaneous malignant melanoma. A primary origin at this site has been reported in rare cases. We report a case of a 71-year-old man with a primary malignant melanoma in the jejunum. The patient presented with weakness, weight loss, non-specific abdominal pain and episodes of fainting. After clinical examination, laboratory evaluation and radiological work-up, which included CT of the abdomen, the patient was diagnosed with a tumour mass in the jejunum. This diagnosis was confirmed at laparotomy. The patient underwent enterectomy with wide excision of the tumour. A primary malignant melanoma of the small intestine is an extremely rare neoplasm.

A definite diagnosis can only be made after a thorough investigation has been made to exclude the co-existence of a primary lesion elsewhere. Curative resection of the tumour remains the treatment of choice.     

Primary malignant melanoma of the bladder

Primary malignant melanomma of bladder is extremely rare: 18 cases are reported to date. An 82 year-old man underwent trans-urethral resection of bladder for a bleeding tumor of the posterior wall. Histological diagnosis was melanoma of the bladder. There was no history of previous or regressed cutaneous malignant melanoma. Margins of the bladder lesion contained atypical melanocytes similar to those commonly seen in the periphery of primary mucous membrane lesions. Clinical studies and radiological examinations were negative for other primary site of melanoma. The patient had a bladder recurrence that was consistent with primary tumor and died of widespread disease 9 months after diagnosis.     

Primary malignant schwannoma of the small bowel.

Primary malignant schwannoma of the small intestine is an extremely rare disease. We report a primary malignant intestinal schwannoma of the small bowel in a 66-year-old woman, who was admitted to the hospital because of fatigue and anaemia. On clinical examination there was a solid mass at the abdomen. Ultrasound scanning showed an abdominal tumour. Computed tomography showed a mass in the area of the pancreatic tail involving the small intestine. At laparotomy a 10 x 10 cm tumour was found in the proximal jejunum, and 50 cm of the small intestine was resected. The histology of the lesion corresponded to a malignant intestinal schwannoma. The results of previous studies and of our report suggest that the diagnosis of malignant intestinal schwannoma may be difficult, and to exclude malignant conditions laparotomy and surgical excision of the tumour are adequate in the management of this type of lesion.     

Oral malignant melanoma detected after resection of amelanotic pulmonary metastasis

INTRODUCTIONSolitary pulmonary metastasis from oral malignant melanoma is very rare.PRESENTATION OF CASEWe demonstrated a 84-year-old patient with a lung nodule that was diagnosed as malignant melanoma by video-assisted thoracoscopic resection. Because primary pulmonary malignant melanoma was extremely rare, the tumor was thought to be a metastasized from an occult primary lesion. A detailed physical examination revealed a black tumor in the oral cavity, and this was suspected to have been the primary. Resection of the hard palate tumor and dissection of the cervical lymph nodes were performed. The patient was simply followed up without further therapy at his request, and he died one year after surgery due to bleeding from a pleural metastasis of malignant melanoma.DISCUSSIONPrimary melanoma of the oral cavity is rare, accounts for 0.5% of all oral cancers, and 0.8–1.8% of all melanomas. Because of absence of symptoms in the early stage of the disease and the presence of the tumor in relatively obscure areas of the oral cavity, the diagnosis is unfortunately often delayed. In view of the rarity of primary lung melanoma, when lung tumor was diagnosed as malignant melanoma, detailed physical examination of the entire skin and mucosa including the oral cavity was necessary.CONCLUSIONOral malignant melanoma was very rare, but oral cavity should be examined when the pulmonary nodule was diagnosed as malignant melanoma.     

Primary malignant melanoma of the esophagogastric junction: Report of a case

INTRODUCTIONPrimary malignant melanoma of the gastrointestinal tract is very rare, especially in the stomach. We report an extremely rare case of primary malignant melanoma of the esophagogastric junction mainly situated in the stomach.PRESENTATION OF CASEThe patient was a 72-year-old woman who complained of shortness of breath due to severe anemia. Upper endoscopy revealed a soft easy-bleeding polypoid tumor just adjacent to the esophagogastric junction in the stomach. Biopsy of the tumor did not indicate a definite result, except malignant tumor. We performed total gastrectomy with splenectomy, and histological and immunohistological examination revealed malignant melanoma of the esophagogastric junction. She had no remote metastasis or lymphnodal metastasis at the point of surgery; however, she died of multiple metastases 11 months after the operation.DISCUSSIONA definite preoperative diagnosis of primary malignant melanoma was very difficult to make from the preoperative biopsy specimen. This present case was first misinterpreted as undifferentiated carcinoma, or malignant lymphoma. Following the diagnosis of malignant melanoma, the question arose as to whether this was primary or metastatic (as malignant melanoma from other sites is known to metastasize to the stomach). Finally this tumor was diagnosed as a primary one due to the pathologic characteristics such as the existence of junctional activities.CONCLUSIONWe report an extremely rare case of primary malignant melanoma of the esophagogastric junction present in the stomach.     

Radiculopathy due to malignant melanoma in the sacrum with unknown primary site

Melanoma is an interesting tumor, showing the appearance of metastasis without any trace of its primary lesion. To report a very rare case of malignant melanoma in the sacrum with unknown primary origin. The authors present a case of a 52-year-old man who was admitted with increasing lower back, left buttock, and left lower extremity pain, and dysuria. Plain radiograph, computed tomography scan, and magnetic resonance imaging revealed a destructive lesion in the sacrum and left ilium, which infiltrated the spinal canal and sacroiliac joint. The tumor cells were immunoreactive for HMB-45. The pathological diagnosis was malignant melanoma. No obvious primary malignant melanoma was detected on the skin surface, on the oral or anal mucosa, or in the fundus oculi. Following radiotherapy and chemotherapy, the severe buttock pain disappeared and the patient was able to walk without impediment. However the patient died nine months after initial diagnosis. Malignant melanoma in the sacrum with an unknown primary site, showing S1 radiculopathy is reported for the first time. The melanoma could have been a metastatic tumor of the sacrum, although the primary site was not detected. The incidence of primary melanoma is increasing faster than any other cancer. Thus treatment of patients with spinal metastasis of melanoma is an important challenge for orthopedic surgeons.

     

Primary malignant melanoma of the female urethra: Report of a rare neoplasm of the urinary tract

IntroductionMelanoma is a malignant tumor that can affect any area of the anatomical economy. Its occurance in the female urethra is extremely rare. We report a case of primary malignant urethral melanoma developed in an elderly female patient.Presentation of caseA 70 years old female presented with dysuria, poor stream, gross haematuria, intermittent blood spots, and a painful mass. On physical examination, there were no suspicious lesions on the skin. On external genital examination, a lesion at the level of the urethral meatus was observed. The mass was removed by wide local excision under spinal anaesthesia. The pathological diagnosis was malignant melanoma of the urethra.DiscussionThe common presentations include bleeding and/or discharge per urethra, voiding dysfunction and the presence of tumor mass. Survival depends on the stage, location and size of the neoplasm at the time of diagnosis. Despite major surgery, radiotherapy or immunotherapy; malignant melanoma usually has a poor prognosis.ConclusionMelanoma of the female urethra is an extremely uncommon pathology leading to paucity of literature and any definite recommendations regarding management. The histological and immunohistochemical findings can be helpful in making an early and accurate diagnosis of malignant melanoma in the urogenital region.     

Ileal Malignant Melanoma Causing Intussusception: Report of a Case

Cutaneous malignant melanoma (MM) often metastasizes to the gastrointestinal (GI) tract; however, primary MM of the small intestine is a controversial diagnosis. We report the case of a 76-year-old woman found to have a primary MM in the ileum. After clinical evaluation, the radiological workup, which included magnetic resonance enteroclysis (MRE), revealed a large polypoid intraluminal tumor. She underwent laparotomy and the lesion was excised. Histological examination of the resected specimen revealed morphological and immunohistochemical characteristics of MM and a detailed postoperative examination failed to identify a primary lesion on the skin, anus, oculus, or any other site. The patient died of brain metastasis 6 months after surgery. According to our review of the literature, this is the first case of primary MM of the small intestine diagnosed with the help of MRE.     

Primary melanoma of small intestine masquerading as gastrointestinal stromal tumor: a case report and literature review

Malignant melanoma of the gastrointestinal tract is a rare entity among intestinal neoplasms. Primary intestinal melanoma is difficult to differentiate from metastatic melanoma, especially given that the primary cutaneous lesion has the potential to regress and disappear. In addition, melanoma by itself is a great mimicker of other neoplastic conditions and may create a major diagnostic challenge when presenting at an intra-abdominal location. Here we report a case of small intestinal melanoma in a 74-year-old female who presented with symptoms of intestinal bleeding and a preoperative clinical and radiological diagnosis of gastrointestinal stromal tumor. The initial frozen section diagnosis also favored gastrointestinal stromal tumor, however furthermore histological and immunohistochemical stain evaluation confirmed the diagnosis of intestinal melanoma.     

Primary malignant melanoma of the rectum: Report of a case

We describe herein a rare case of primary malignant melanoma of the rectum in an 85-year-old woman. The patient presented with intermittent rectal bleeding, and a colonoscopy revealed an ulcerated polypoid mass in the rectum, located 5 cm from the anal verge. The lesion was histologically characterized by solid growths of small round cells with scanty cytoplasm and prominent nucleoli. Although no melanin pigment was found in the tumor cells, they were immunohistochemically positive for HMB-45, a monoclonal antibody highly specific for malignant melanoma. Thus, HMB-45 proved very useful to establish a diagnosis of amelanotic malignant melanoma of the rectum.     

人原发性小肠恶性黑色素瘤裸小鼠原位移植肝转移模型的建立

目的为探讨小肠恶性黑色素瘤的发病机制和实验治疗提供理想的动物模型。方法将原发性小肠恶性黑色素瘤患者术中原发灶和肝转移灶新鲜瘤组织块分别植入裸小鼠的小肠黏膜层，观察原位移植成瘤率，移植瘤的侵袭和肝转移率。进行形态学[光镜、电镜和免疫组织化学（免疫组化）]染色体核型和流式细胞分析。结果人小肠恶性黑色素瘤原发灶和肝转移灶新鲜瘤组织均获移植成功。建成一株人原发性小肠（原发灶）恶性黑色素瘤裸鼠原位移植模型（HSIM-0501）和一株人原发性小肠（肝转移灶）恶性黑色素瘤裸鼠原位移植肝转移模型（HSIM-0502）。移植瘤组织病理学为高度恶性黑色素瘤；免疫组化显示S-100蛋白；黑色素瘤单克隆抗体45阳性；电镜下瘤细胞质内可见大量黑色素颗粒及黑色素复合体。染色体众数55～59条；流式细胞DNA指数值1．49-1．61；均为异倍体。HSIM-0501和HSIM-0502分别传至25代和27代；共移植裸鼠317只；肿瘤移植成瘤率和液氮冻存复苏成活率均为100％。HSIM-0501肝转移率为46．2％，淋巴结转移率为36．7％；HSIM-0502肝转移率和淋巴结转移率均为100％。移植瘤在裸鼠小肠内自主侵袭生长，发生血液转移、淋巴结转移和腹腔内种植性转移。结论HSIM-0501和HSIM-0502是首次成功建立的人原发性小肠恶性黑色素裸鼠原位移植肝转移模型，可用于小肠恶性黑色素瘤的发病机制、侵袭和转移及抗转移实验治疗的研究。     

Primitive cerebral melanoma: case report and review of the literature

BACKGROUND: Central nervous system primary malignant melanoma accounts for approximately 1% of all the cases of melanoma; reports in the literature are relatively rare. CASE DESCRIPTION: A 74-year-old man was hospitalized because of an episode of aphasia. The neuroradiologic examinations demonstrated a round homogeneous lesion extending near the left sylvian fissure. He had no extracranial abnormalities. The patient underwent a neurosurgical procedure and the tumor was macroscopically totally excised. Pathological examination of the surgical specimen revealed a histological appearance similar to that of melanoma. A diagnosis of primary CNS melanoma was made after careful dermatologic and ophthalmologic examination, which ruled out presence of cutaneous or choroidal melanoma. The patient did not receive any further treatment and he is free of disease 2 years after diagnosis. CONCLUSIONS: We report a case of primary cerebral melanoma of the left temporal lobe; clinical, neuroradiological, and histological findings are discussed with review of the literature. Primary melanoma of the CNS may present either with localized intra/extra-axial mass lesions or with meningeal spread, which carries a worse prognosis. The prognosis of cerebral primitive melanoma is variable, although it is common opinion that primitive cerebral melanoma has a better prognosis than cutaneous melanoma, with two cases in the literature surviving 9 and 12 years.     

Primary biliary tract melanoma: Report of a case and review of the literature

INTRODUCTIONPrimary melanoma of the bile duct is extremely rare with only nine cases of primary melanoma of the bile duct reported in the literature.PRESENTATION OF CASEA 55-year-old previously healthy gentleman developed increasing jaundice over several months and subsequently underwent an ERCP with stone extraction. Cytology brushings in an area of a distal stricture in the bile duct were concerning for cholangiocarcinoma. The patient was referred to our institution and underwent a pancreaticoduodenectomy. The surgical specimen showed a single 4.5 cm polypoid lesion located in the bile duct. A diagnosis of melanoma was rendered after immunohistochemical studies on the tumor demonstrated positivity for melanoma markers. Follow-up of the patient with skin, ocular, and lymph node exams showed no evidence of melanoma. A PET scan 4 and 10 months post-surgery failed to reveal either a primary skin lesion or other sites of metastases.DISCUSSIONThe vast majority of melanomas of the bile duct represent metastases from a cutaneous source and tend to present as multiple flat pigmented lesions. Conversely, cases of primary bile duct melanoma are characterized by a distinct gross morphology consisting of a solitary intraluminal polypoid lesion attached by a pedicle with no other identifiable primary lesion. Other supporting criteria include absence of other involved sites and presence of an in situ junctional component.CONCLUSIONGiven the clinical history, gross findings, and lack of a primary cutaneous site or other demonstrable metastases, this patient likely represents the tenth reported case of primary biliary tract melanoma.     

Primary mucosal malignant melanoma of the oral cavity

Mucosal malignant melanoma arising from the head and neck region is a rare entity, and it is more aggressive than cutaneous melanoma. Furthermore, the complex anatomy of the oral cavity makes complete surgical excision difficult. Thus, early diagnosis and treatment of a mucosal lesion are important. In this study, three mucosal malignant melanoma cases and the literature have been reviewed. Three cases who presented with a primary malignant melanoma of the oral cavity have been retrospectively analyzed. All three patients were female with a mean age of 31.3 years, and the median follow-up period was 18.6 (6–36) months. The tumor was located on the maxillary gingiva in case 1 and in the hard palate–maxillary gingiva in cases 2 and 3. Case 2 had a distant metastasis during first admission. The tumor was excised with a 2-cm surgical margin in all cases. Case 2 received adjuvant chemotherapy. During the follow-up period, case 1 had a cervical lymphadenopathy 8 months after the first operation, so she underwent cervical lymph node dissection then received chemotherapy. Melanoma of the oral cavity is very rare with an extremely poor prognosis. As some melanomas may be amelanotic, a high index of suspicion is necessary. A biopsy should be taken from any suspicious lesion in the oral cavity. Surgical excision combined with adjuvant therapy is the main treatment approach for these cases. Prognosis of the disease depends on early diagnosis and treatment. A multicenter prospective study is required to introduce staging of the disease and the optimal treatment regimen.     

A case report of anorectal malignant melanoma with mucosal skipped lesion

IntroductionWe report our experience involving a case of relatively rare anorectal malignant melanoma with skipped lesion.Presentation of caseThe patient was a 72-year-old man who had visited a local clinic complaining of a mass in the anal region, whereupon he was referred to our hospital on suspicion of a malignant melanoma. Close examination revealed a 25-mm black type 1 tumor one-third the size of the circumference of the anal canal and located externally to it. We performed transanal resection of the tumor and confirmed a diagnosis of malignant melanoma. Notably, multiple macular black lesions spaced away from the main lesion were observed during surgery in half of the circumference of the anal canal, from the tumor to the pectinate line. A biopsy of the area also revealed malignant melanoma; therefore, we performed abdominoperineal resection. Pathological diagnosis indicated a submucosal depth; the patient was thus diagnosed with T4 N2c M0 stage IIIb malignant melanoma and was followed on an outpatient basis.DiscussionPatients with anorectal malignant melanoma have very poor prognoses owing to early lymph node metastasis and hematogenous metastasis. Our case illustrates that small anorectal malignant melanoma lesions can spread from the main lesion and invade the mucosa; examinations may sometimes miss such skipped lesions.ConclusionSkipped lesions can occur in anorectal melanomas; thus, careful scrutiny of such lesions is required. Moreover, lesion resection is critical for anorectal malignant melanomas.     

Primary Localized Amyloidosis of the Small Intestine Presenting as an Intestinal Pseudo-obstruction: Report of a Case

A 47-year-old man with primary amyloidosis confined to the small intestine is reported. Thickening of the folds and multiple polypoid protrusions were found in the duodenum by upper gastrointestinal endoscopy. Because the patient presented with a persistent intestinal pseudo-obstruction, partial jejunectomy was performed. Histological examination of the resected tissue revealed massive deposits of amyloid throughout the jejunal wall. Neither a predisposing condition nor any other sites of deposition were found, and primary amyloidosis of the small intestine was diagnosed. This rare form of amyloid deposition should be recognized so that an early diagnosis can be made.     

Sarcoma of the Abdominal Aorta Involving Marginal Arteries of the Small Intestine: A Case Report

Primary sarcoma of the aorta is extremely rare. In the past, the disease was commonly diagnosed on autopsy. However, now it is possible to make a diagnosis preoperatively using various imaging studies such as computed tomographic scanning and magnetic resonance imaging. The authors have experienced one case of abdominal aortic sarcoma in a patient who complained of the symptoms of typical intestinal angina. We diagnosed an aortic sarcoma preoperatively but failed to resect the tumor on thoracolaparotomy because of the tumor extension to marginal arteries of the whole small intestine. We recommend preoperative laparoscopy for evaluation of tumor extension to marginal arteries of the small intestine in a patient having aortic sarcoma and intestinal angina if the patient is considered to be a surgical candidate.     

A rare primary sellar melanoma. Case report

The authors report on the case of a 37-year-old woman in whom a primary sellar malignant melanoma mimicking a hemorrhagic pituitary macroadenoma was treated. This entity is exceedingly rare; only five cases are described in the literature. The patient presented with rapid deterioration of vision within a 2-week period. After an ophthalmological diagnosis of chiasmal syndrome was made, magnetic resonance (MR) imaging of the head revealed an intra- and suprasellar mass that was elevating and compressing the optic chiasm. Because of the signal heterogeneity of the lesion a hemorrhagic pituitary macroadenoma was assumed; the lesion was transsphenoidally resected. Histological examination of the specimen showed a malignant melanocytic tumor with immunopositivity for S100 protein and HMB-45. Despite extensive staging no other primary melanotic tumor was found. Thus, a primary sellar melanoma was diagnosed. Postoperative MR images demonstrated no residual tumor. For adjuvant therapy the region around the sella turcica received 40.4 Gy stereotactically guided radiation. A 24-month follow-up examination revealed no tumor recurrence. This represents the sixth case of such a lesion reported in the literature, the third case evaluated using MR imaging, and the first case with a progression-free survival of 24 months. Thus, the authors advocate that management of primary sellar melanoma should include gross-total removal and postoperative stereotactic radiotherapy.