Images for surgeons
520
References
Fig. 3. Cystic mass arising from appendix, identified after mobilization of ascending colon for right hemicolectomy.
cellular atypia, signet ring cells and high mitotic rates.7 Both forms have the potential to disseminate mucin throughout the peritoneal cavity; however, only PMCA tumours have the ability to metastasize to lymph nodes and directly invade surrounding tissues. In the early 1990s, Sugerbaker used the combination of cytoreductive surgery and heated intraperitoneal chemotherapy (HIPEC) as a new treatment for patients with pseudomyxoma peritonei. The group reported a 5‐year survival of up to 86% in patients with DPAM and between 20 and 50% in patients with PMCA.8 Mortality of 5% following cytoreductive surgery with HIPEC, and morbidity of 35%, highlight the importance of recognizing mucinous tumours pre‐operatively, where possible, and ensuring that all care is taken intra‐operatively to prevent spillage that may lead to pseudomyxoma peritonei.
1. Weaver CH. Mucocele of the appendix with pseudomucinous degeneration. Am. J. Surg. 1937; 36: 523. 2. Smeenk RM, van Velthuysen MLF, Verwaal VJ, Zoetmulder FAN. Appendiceal neoplasms and pseudomyxoma peritonei: a population based study. Eur. J. Surg. Oncol. 2008; 34: 196–201. 3. Connor SJ, Hanna GB, Frizelle FA. Appendiceal tumors: retrospective clinicopathologic analysis of appendiceal tumors from 7,970 appendectomies. Dis. Colon Rectum. 1998; 41: 75–80. 4. Shankar S, Ledakis P, El Halabi H, Gushchin V, Sardi A. Neoplasms of the appendix: current treatment guidelines. Hematol. Oncol. Clin. North Am. 2012; 26: 1261–90. 5. Votanopoulos KI, Shen P, Stewart JH, Levine EA. Current status and future directions in appendiceal cancer with peritoneal dissemination. Surg. Oncol. Clin. N. Am. 2012; 21: 599–609. 6. O'Connell JT, Hacker CM, Barsky SH. MUC2 is a molecular marker for pseudomyxoma peritonei. Mod. Pathol. 2002; 15: 958–72. 7. Ronnett BM, Zahn CM, Kurman RJ. Disseminated peritoneal adenomucinosis and peritoneal mucinous carcinomatosis. A clinicopathologic analysis of 109 cases with emphasis on distinguishing pathologic features, site of origin, prognosis, and relationship to ‘pseudomyxoma peritonei’. Am. J. Surg. Pathol. 1995; 19: 1390–408. 8. Sugarbaker PH, Chang D. Results of treatment of 385 patients with peritoneal surface spread of appendiceal malignancy. Ann. Surg. Oncol. 1999; 6: 727–31.
Christopher Richard McDonald, MBBS, FRACS Gregory John Nolan, MBBS, FRACS Darren Matthew Tonkin, MBBS, FRACS Department of Colorectal Surgery, The Queen Elizabeth Hospital, Adelaide, South Australia, Australia doi: 10.1111/ans.12717
Intra‐abdominal metastatic melanoma presenting as intussusception A 50‐year‐old Caucasian man presented to the emergency department with a 3‐month history of epigastric pain, melaena, weight loss, anorexia and lethargy. He had a history of hard palate melanoma diagnosed 6 years ago. Initial biopsy revealed in situ oral mucosal malignant melanoma. Wide local excision of the hard palate at a major tertiary hospital revealed extensive in situ melanoma involving the margins (0.63 mm thick). He underwent six re‐excision operations over a 5‐month period. The initial histopathological reports revealed persistent atypical melanocytic hyperplasia. However, the final re‐excision revealed no evidence of malignancy. He subsequently received biannual specialist follow‐up for 6 years. No abnormalities were noted during this time. Upon examination, he was afebrile with stable vital signs. His abdomen was soft. However, he had epigastric tenderness with mild abdominal distension. The haemoglobin was 99 g/L and C‐ reactive protein was 213 mg/L. A computed tomography (CT) of
his abdomen revealed multiple foci of thickened small bowel with two regions forming lead points for intussusception. The proximal intussusceptum was seen in the upper right quadrant (Fig. 1), and the distal intussusceptum causing small bowel obstruction was located in the lower left quadrant (Fig. 2). Further radiological findings suggestive of metastases included pulmonary nodules, focal densities within the liver, abnormal enhancing wall thickening of the gall bladder and nodular thickening of the adrenal glands. During exploratory laparotomy, multiple deposits of melanoma were found in the small bowel, lymph nodes and omentum (Fig. 3). Due to the extensive involvement of small bowel, formal resection of all metastatic deposits was not performed. The portion of bowel causing obstruction was resected, thereby providing adequate palliation. The patient made an unremarkable recovery after the surgery. He was referred to the medical oncology unit for palliative
© 2014 Royal Australasian College of Surgeons
Images for surgeons
Fig. 1. Focus of bowel wall thickening forming a lead point for proximal intussusception in the jejunum: (a) coronal and (b) sagittal.
Fig. 2. Second focus of bowel thickening causing distal intussusception and leading to proximal obstruction: (a) coronal and (b) sagittal.
Fig. 3. Multiple foci of metastatic melanoma in the bowel and omentum.
© 2014 Royal Australasian College of Surgeons
521
Images for surgeons
522
chemotherapy and enrolment in a clinical trial (nivolumab versus dacarbazine). Histopathological analysis of the specimen reported three synchronous deposits of malignant melanoma (poorly differentiated, with enlarged pleomorphic nuclei and prominent nucleoli) involving mucosa and full thickness of the bowel wall. Screening for V600E and V600K mutations in the BRAF gene was carried out but no mutations were detected. Malignant melanoma is one of the most common malignancies to metastasize to the gastrointestinal (GI) tract, and the small intestine represents the most frequent site for metastatic melanoma.1 Of note, 2–5% of patients with cutaneous melanoma will suffer from a small bowel metastasis. Conversely, melanoma accounts for approximately 30% of all metastases to the small bowel.2 Primary oral mucosal malignant melanoma is a rare neoplasm developing from melanocytes found in the basal layer of the oral mucosa and represents 0.2–8% of all melanomas.3 Black, Japanese and Asian patients are more commonly affected than Whites. Oral melanoma frequently exhibits an extremely invasive behaviour, with vertical growth, high index of metastasis and poor prognosis.4 The risk factors for the spread of malignant melanoma to the GI tract include superficial spreading melanoma, axial primary tumour, a Clark level III or IV, a high degree of histological regression, presence of ulceration and a high mitotic rate.2 Symptoms often mimic those of other GI tumours and include abdominal pain, fatigue, dysphagia, constipation, tenesmus, small bowel obstruction, perforated bowel, melaena and anaemia.5 Radiological diagnosis is difficult as CT scans and small bowel follow‐through are often unreliable for detection of melanoma metastases in the small bowel.6 On the contrary, CT can detect intussusception, and mesenteric and omental deposits.7 As a result, intestinal metastatic disease is often not detected in the early stages. Therefore, diagnosis is often not made until complications occur. The interval between the diagnosis of primary malignant melanoma and clinical manifestation of GI metastases ranges from 2 to 180 months.8 This should prompt a careful clinical follow‐up of patients with a history of high‐risk melanoma who present with GI symptoms. The prognosis of patients with metastatic melanoma is poor, with a mean survival of 6–8 months. Five‐year survival rates are reported as 10% or less.2,9 It is now widely accepted that aggressive surgical resection in patients with metastatic melanoma is the treatment of choice, conferring both palliative and survival advantages.2,10
In conclusion, metastatic melanoma in the GI tract should be suspected in patients with history of melanoma and acute GI symptoms. Immediate laparotomy and radical excision of the affected bowel segment is the appropriate treatment.
References 1. Patel JK, Didolkar MS, Pickren JW, Moore RH. Metastatic pattern of malignant melanoma. A study of 216 autopsy cases. Am. J. Surg. 1978; 135: 807–10. 2. Mucci T, Long W, Witkiewicz A, Mastrangelo MJ, Rosato EL, Berger AC. Metastatic melanoma causing jejunal intussusception. J. Gastrointest. Surg. 2007; 11: 1755–7. 3. Rapidis AD, Apostolidis C, Vilos G, Valsamis S. Primary malignant melanoma of the oral mucosa. J. Oral Maxillofac. Surg. 2003; 61: 1132–9. 4. Little JW. Melanoma: etiology, treatment, and dental implications. Gen. Dent. 2006; 54: 61–6. 5. Hao XS, Li Q, Chen H. Small bowel metastases of malignant melanoma: palliative effect of surgical resection. Jpn J. Clin. Oncol. 1999; 29: 442–4. 6. Allen PJ, Coit DG. The surgical management of metastatic melanoma. Ann. Surg. Oncol. 2002; 9: 762–70. 7. Agrawal S, Yao TJ, Coit DG. Surgery for melanoma metastatic to the gastrointestinal tract. Ann. Surg. Oncol. 1999; 6: 336–44. 8. Schuchter LM, Green R, Fraker D. Primary and metastatic diseases in malignant melanoma of the gastrointestinal tract. Curr. Opin. Oncol. 2000; 12: 181–5. 9. Gatsoulis N, Roukounakis N, Kafetzis I, Gasteratos S, Mavrakis G. Small bowel intussusception due to metastatic malignant melanoma. A case report. Tech. Coloproctol. 2004; 8: s141–3. 10. Bender GN, Maglinte DD, McLarney JH, Rex D, Kelvin FM. Malignant melanoma: patterns of metastasis to the small bowel, reliability of imaging studies, and clinical relevance. Am. J. Gastroenterol. 2001; 96: 2392–400.
Chin Li Tee, MBBS Michael Basedow, MBBS Boris Strekozov, MD, FRACS Department of Surgery, Caboolture Hospital, Caboolture, Queensland, Australia This paper was presented as a poster at the Asian Congress of Surgery held on 19–21 July 2013 in Singapore. doi: 10.1111/ans.12728
© 2014 Royal Australasian College of Surgeons
520
References
Fig. 3. Cystic mass arising from appendix, identified after mobilization of ascending colon for right hemicolectomy.
cellular atypia, signet ring cells and high mitotic rates.7 Both forms have the potential to disseminate mucin throughout the peritoneal cavity; however, only PMCA tumours have the ability to metastasize to lymph nodes and directly invade surrounding tissues. In the early 1990s, Sugerbaker used the combination of cytoreductive surgery and heated intraperitoneal chemotherapy (HIPEC) as a new treatment for patients with pseudomyxoma peritonei. The group reported a 5‐year survival of up to 86% in patients with DPAM and between 20 and 50% in patients with PMCA.8 Mortality of 5% following cytoreductive surgery with HIPEC, and morbidity of 35%, highlight the importance of recognizing mucinous tumours pre‐operatively, where possible, and ensuring that all care is taken intra‐operatively to prevent spillage that may lead to pseudomyxoma peritonei.
1. Weaver CH. Mucocele of the appendix with pseudomucinous degeneration. Am. J. Surg. 1937; 36: 523. 2. Smeenk RM, van Velthuysen MLF, Verwaal VJ, Zoetmulder FAN. Appendiceal neoplasms and pseudomyxoma peritonei: a population based study. Eur. J. Surg. Oncol. 2008; 34: 196–201. 3. Connor SJ, Hanna GB, Frizelle FA. Appendiceal tumors: retrospective clinicopathologic analysis of appendiceal tumors from 7,970 appendectomies. Dis. Colon Rectum. 1998; 41: 75–80. 4. Shankar S, Ledakis P, El Halabi H, Gushchin V, Sardi A. Neoplasms of the appendix: current treatment guidelines. Hematol. Oncol. Clin. North Am. 2012; 26: 1261–90. 5. Votanopoulos KI, Shen P, Stewart JH, Levine EA. Current status and future directions in appendiceal cancer with peritoneal dissemination. Surg. Oncol. Clin. N. Am. 2012; 21: 599–609. 6. O'Connell JT, Hacker CM, Barsky SH. MUC2 is a molecular marker for pseudomyxoma peritonei. Mod. Pathol. 2002; 15: 958–72. 7. Ronnett BM, Zahn CM, Kurman RJ. Disseminated peritoneal adenomucinosis and peritoneal mucinous carcinomatosis. A clinicopathologic analysis of 109 cases with emphasis on distinguishing pathologic features, site of origin, prognosis, and relationship to ‘pseudomyxoma peritonei’. Am. J. Surg. Pathol. 1995; 19: 1390–408. 8. Sugarbaker PH, Chang D. Results of treatment of 385 patients with peritoneal surface spread of appendiceal malignancy. Ann. Surg. Oncol. 1999; 6: 727–31.
Christopher Richard McDonald, MBBS, FRACS Gregory John Nolan, MBBS, FRACS Darren Matthew Tonkin, MBBS, FRACS Department of Colorectal Surgery, The Queen Elizabeth Hospital, Adelaide, South Australia, Australia doi: 10.1111/ans.12717
Intra‐abdominal metastatic melanoma presenting as intussusception A 50‐year‐old Caucasian man presented to the emergency department with a 3‐month history of epigastric pain, melaena, weight loss, anorexia and lethargy. He had a history of hard palate melanoma diagnosed 6 years ago. Initial biopsy revealed in situ oral mucosal malignant melanoma. Wide local excision of the hard palate at a major tertiary hospital revealed extensive in situ melanoma involving the margins (0.63 mm thick). He underwent six re‐excision operations over a 5‐month period. The initial histopathological reports revealed persistent atypical melanocytic hyperplasia. However, the final re‐excision revealed no evidence of malignancy. He subsequently received biannual specialist follow‐up for 6 years. No abnormalities were noted during this time. Upon examination, he was afebrile with stable vital signs. His abdomen was soft. However, he had epigastric tenderness with mild abdominal distension. The haemoglobin was 99 g/L and C‐ reactive protein was 213 mg/L. A computed tomography (CT) of
his abdomen revealed multiple foci of thickened small bowel with two regions forming lead points for intussusception. The proximal intussusceptum was seen in the upper right quadrant (Fig. 1), and the distal intussusceptum causing small bowel obstruction was located in the lower left quadrant (Fig. 2). Further radiological findings suggestive of metastases included pulmonary nodules, focal densities within the liver, abnormal enhancing wall thickening of the gall bladder and nodular thickening of the adrenal glands. During exploratory laparotomy, multiple deposits of melanoma were found in the small bowel, lymph nodes and omentum (Fig. 3). Due to the extensive involvement of small bowel, formal resection of all metastatic deposits was not performed. The portion of bowel causing obstruction was resected, thereby providing adequate palliation. The patient made an unremarkable recovery after the surgery. He was referred to the medical oncology unit for palliative
© 2014 Royal Australasian College of Surgeons
Images for surgeons
Fig. 1. Focus of bowel wall thickening forming a lead point for proximal intussusception in the jejunum: (a) coronal and (b) sagittal.
Fig. 2. Second focus of bowel thickening causing distal intussusception and leading to proximal obstruction: (a) coronal and (b) sagittal.
Fig. 3. Multiple foci of metastatic melanoma in the bowel and omentum.
© 2014 Royal Australasian College of Surgeons
521
Images for surgeons
522
chemotherapy and enrolment in a clinical trial (nivolumab versus dacarbazine). Histopathological analysis of the specimen reported three synchronous deposits of malignant melanoma (poorly differentiated, with enlarged pleomorphic nuclei and prominent nucleoli) involving mucosa and full thickness of the bowel wall. Screening for V600E and V600K mutations in the BRAF gene was carried out but no mutations were detected. Malignant melanoma is one of the most common malignancies to metastasize to the gastrointestinal (GI) tract, and the small intestine represents the most frequent site for metastatic melanoma.1 Of note, 2–5% of patients with cutaneous melanoma will suffer from a small bowel metastasis. Conversely, melanoma accounts for approximately 30% of all metastases to the small bowel.2 Primary oral mucosal malignant melanoma is a rare neoplasm developing from melanocytes found in the basal layer of the oral mucosa and represents 0.2–8% of all melanomas.3 Black, Japanese and Asian patients are more commonly affected than Whites. Oral melanoma frequently exhibits an extremely invasive behaviour, with vertical growth, high index of metastasis and poor prognosis.4 The risk factors for the spread of malignant melanoma to the GI tract include superficial spreading melanoma, axial primary tumour, a Clark level III or IV, a high degree of histological regression, presence of ulceration and a high mitotic rate.2 Symptoms often mimic those of other GI tumours and include abdominal pain, fatigue, dysphagia, constipation, tenesmus, small bowel obstruction, perforated bowel, melaena and anaemia.5 Radiological diagnosis is difficult as CT scans and small bowel follow‐through are often unreliable for detection of melanoma metastases in the small bowel.6 On the contrary, CT can detect intussusception, and mesenteric and omental deposits.7 As a result, intestinal metastatic disease is often not detected in the early stages. Therefore, diagnosis is often not made until complications occur. The interval between the diagnosis of primary malignant melanoma and clinical manifestation of GI metastases ranges from 2 to 180 months.8 This should prompt a careful clinical follow‐up of patients with a history of high‐risk melanoma who present with GI symptoms. The prognosis of patients with metastatic melanoma is poor, with a mean survival of 6–8 months. Five‐year survival rates are reported as 10% or less.2,9 It is now widely accepted that aggressive surgical resection in patients with metastatic melanoma is the treatment of choice, conferring both palliative and survival advantages.2,10
In conclusion, metastatic melanoma in the GI tract should be suspected in patients with history of melanoma and acute GI symptoms. Immediate laparotomy and radical excision of the affected bowel segment is the appropriate treatment.
References 1. Patel JK, Didolkar MS, Pickren JW, Moore RH. Metastatic pattern of malignant melanoma. A study of 216 autopsy cases. Am. J. Surg. 1978; 135: 807–10. 2. Mucci T, Long W, Witkiewicz A, Mastrangelo MJ, Rosato EL, Berger AC. Metastatic melanoma causing jejunal intussusception. J. Gastrointest. Surg. 2007; 11: 1755–7. 3. Rapidis AD, Apostolidis C, Vilos G, Valsamis S. Primary malignant melanoma of the oral mucosa. J. Oral Maxillofac. Surg. 2003; 61: 1132–9. 4. Little JW. Melanoma: etiology, treatment, and dental implications. Gen. Dent. 2006; 54: 61–6. 5. Hao XS, Li Q, Chen H. Small bowel metastases of malignant melanoma: palliative effect of surgical resection. Jpn J. Clin. Oncol. 1999; 29: 442–4. 6. Allen PJ, Coit DG. The surgical management of metastatic melanoma. Ann. Surg. Oncol. 2002; 9: 762–70. 7. Agrawal S, Yao TJ, Coit DG. Surgery for melanoma metastatic to the gastrointestinal tract. Ann. Surg. Oncol. 1999; 6: 336–44. 8. Schuchter LM, Green R, Fraker D. Primary and metastatic diseases in malignant melanoma of the gastrointestinal tract. Curr. Opin. Oncol. 2000; 12: 181–5. 9. Gatsoulis N, Roukounakis N, Kafetzis I, Gasteratos S, Mavrakis G. Small bowel intussusception due to metastatic malignant melanoma. A case report. Tech. Coloproctol. 2004; 8: s141–3. 10. Bender GN, Maglinte DD, McLarney JH, Rex D, Kelvin FM. Malignant melanoma: patterns of metastasis to the small bowel, reliability of imaging studies, and clinical relevance. Am. J. Gastroenterol. 2001; 96: 2392–400.
Chin Li Tee, MBBS Michael Basedow, MBBS Boris Strekozov, MD, FRACS Department of Surgery, Caboolture Hospital, Caboolture, Queensland, Australia This paper was presented as a poster at the Asian Congress of Surgery held on 19–21 July 2013 in Singapore. doi: 10.1111/ans.12728
© 2014 Royal Australasian College of Surgeons
