Friday, June 19, 2015

President's Message June 2015

Dear Friends and Colleagues,

I hope everyone is doing well as the 2014-2015 academic year is about to end. Our Companion Meeting that was held during the USCAP Annual Meeting in Boston this past March was well-attended and a great success. We garnered high marks and positive feedback from the attendees. Congratulations are in order to all the speakers for this achievement.

The society membership voted upon the proposed modifications to the HPHS By-Laws during the Business Meeting that immediately followed the Companion Meeting. One of the changes that was approved included formalizing the creation of a Website Committee. Its inaugural chair, Arief Suriawinata, reported that the Interesting Case Series published in both the Newsletter and the HPHS website resulted in a record number of web visits (page views). As an aside, as of today, June 15, 2015, per Arief, there have been 16,742 visits to the website. This huge increase is mainly due to the Case Series that is being made available to the general public.

This Case Series section would not have been possible without the Education Committee’s dedication and resolve to generate interesting cases under the leadership of Oyedele Adeyi and the section editor, Cynthia Guy. In addition to the Cases, a new section, Journal Watch, was proposed by Dele Adeyi, which the Exec Com approved today. This will commence in the next issue of the Newsletter. This tremendous accomplishment is giving greater visibility to liver pathology and our Society. This Newsletter would not be possible without the Newsletter Committee chaired by Bita Naini and its very active members, Steve Ward, Erin Rubin and Cynthia Behling, who have worked very hard to keep this Newsletter coming out on a regular basis.

The Membership Committee members chaired by Maha Guindi were kept busy as the USCAP meeting was approaching because applications for membership were at an all-time high this year. A total of 22 were approved for membership (11 regular, 10 associate and 1 international). The By-Laws were also modified to include deliberations for membership to occur quarterly or even on a rolling basis as the need arises. This will hopefully result in keeping a potential member to be interested in the society and not wait for several months before a decision is made.

The HPHS was involved in putting together the liver pathology program at the Asia Pacific International Academy of Pathology that was held in Brisbane two weeks ago. The speakers included Yoh Zen, Yasuni Nakanuma, Young-Nyun Park, Andrew Clouston and Anthony Chan. This was also a successful meeting.

I am lucky to have the help and counsel from the other members of the Executive Committee: Michael Torbenson (incoming President), Matthew Yeh (Past President) and Grace Kim (Secretary-Treasurer) who work diligently behind the scenes but equally share in the responsibilities and challenges of keeping our Society flourishing.

The next newsletter will be published in three months and there will be more to come. I wish everyone a great summer.

Sincerely,

M. Isabel Fiel, M.D.
President,
Hans Popper Hepatopathology Society

Interesting Case June 2015 #1

Case History: 

A 47 year old man with a past medical history of diabetes, hypertension, and obesity presented with abdominal pain, abdominal distension, and lower extremity swelling. A multiphase MRI of the liver revealed multiple calcified and non-calcified hypoenhancing masses, more confluent in, and involving most of, the right hepatic lobe. Smaller discrete lesions were seen in the left lobe, measuring up to 4.1 cm. The right portal vein showed findings suspicious for tumor thrombus. Needle-core biopsies were performed.

Figure 1: 4x, 1st biopsy core.

Figure 2: 10x, 1st biopsy core.

Figure 3: 20x, 1st biopsy core.

Figure 4: 40x, 1st biopsy core.

Figure 5: 40x, 1st biopsy core.

Figure 6: CD34, 1st biopsy core.

Figure 7: 10x, 2nd biopsy core.

Figure 8: 40x, 2nd biopsy core.

Figure 9: CD34, 2nd biopsy core.

Figure 10: CD34, 2nd biopsy core.
In addition to the CD34 immunohistochemistry (IHC) stain shown, the lesional cells were positive for CD31 and Factor VIII.

Diagnosis: 

Epithelioid Hemangioendothelioma

Discussion: 

Epithelioid Hemangioendothelioma (EHE) is a rare, low grade vascular malignancy that was first recognized as a distinct clinicopathologic entity in the early 1980s in the soft tissues and lung. In the latter organ it was originally referred to as intravascular bronchioloalveolar tumor (IVBAT). It is now known to occur in many sites, including the liver.

Its histologic features are quite distinctive in the liver. In hepatic EHE the tumor is often multifocal, with calcifications seen radiographically. They are firm, white to yellow, with ill-defined borders. Tumor cells are both dendritic and epithelioid in various proportions. The spindle cells are irregularly shaped and elongated. Epithelioid cells are rounder with more abundant eosinophilic cytoplasm. Small papillations or tufts of tumor cells may be seen within thin-walled vascular spaces. Abortive vascular differentiation is typically seen, with tumor cell cytoplasm containing a single vacuole representing a capillary luminal space — so-called “blister cells.” Tumor cells lie within a variably myxoid to fibrous stroma. The tumor often infiltrates hepatic vein and portal vein branches, leading to Budd-Chiari syndrome as a possible presentation. The tumor tends to grow around and leave pre-existing hepatic structures intact, particularly at the periphery of tumor nodules. In these areas, only subtle infiltration of tumor cells may be seen within sinusoids, in an otherwise architecturally normal liver, something which can be particularly treacherous in small liver biopsies.

On core biopsy material, the differential diagnosis can be separated into two distinct categories:

  1. the lesion is clearly neoplastic but the histogenesis of the tumor is not obvious
  2. fibrosis vs. EHE.

In the first setting, the lesion is sufficiently cellular and atypical to be clearly neoplastic, and the differential diagnosis often includes carcinomas such as hepatocellular carcinoma, cholangiocarcinoma, or metastatic carcinoma. IHC stains for vascular markers (CD34, CD31, Factor VIII, FLI1), are typically positive in EHEs and negative in carcinomas. Patchy keratin staining can be seen in some tumor cells of EHE, or in entrapped hepatocytes or bile ducts, and care should be taken not to misdiagnose a carcinoma.

In the second setting, the tumor is hypocellular and has a fibrotic stroma, and can closely mimic fibrosis or confluent necrosis with drop-out. In this setting, the tumor can be very difficult to diagnose on limited core biopsy material. One can look for focal areas of greater cytologic atypia, or areas of sinusoidal infiltration of tumor cells. A vascular IHC stain can be helpful to highlight such infiltration, keeping in mind not to misinterpret capillarization of sinusoids, which can be seen in various settings.

The largest series on hepatic EHE is from the AFIP, in which 137 cases were described. It typically occurs in middle-aged adults (though rare cases in children have been reported), with a slight female predominance. It presents with non-specific symptoms such as abdominal pain, nausea and vomiting, hepatosplenomegaly, or as Budd-Chiari syndrome, or as an incidental finding. It is slowly progressive and treated with excision, or transplantation in advanced cases. In this presented case, the patient was immediately referred for liver transplantation. Because the tumor grows so slowly, transplantation can still be performed in the presence of extra-hepatic disease. Overall 5-year survival rate is 43-55%.

More recently, a characteristic translocation has been reported: t(1;3)(p36.3;q25), resulting in a WWTR1-CAMTA1 fusion. This translocation has been shown to occur in the majority of EHEs of various sites, and not in their histologic mimics. A smaller subset of EHEs show a YAP1-TFE3 fusion. A recent study showed a high sensitivity and specificity for a CAMTA1 IHC stain, suggesting its possible utility as a diagnostic marker.

References

Antonescu CR, et al. Novel YAP1-TFE3 fusion defines a distinct subset of epithelioid hemangioendothelioma. Genes Chromosomes Cancer 2013; 52: 775-784.
Errani C, et al. A Novel WWTR1-CAMTA1 Gene Fusion is a Consistent Abnormality in Epithelioid Hemangioendothelioma of Different Anatomic Sites. Genes Chromosomes Cancer 2011; 50: 644-653.
Makhlouf HR, Ishak KG, Goodman ZD. Epithelioid hemangioendothelioma of the liver: a clinicopathologic study of 137 cases. Cancer 1999; 85: 562-582.
Mehrabi A, et al. Primary malignant hepatic epithelioid hemangioendothelioma: a comprehensive review of the literature with emphasis on surgical therapy. Cancer 2006; 107: 2108-2121.
Shibuya R, et al. CAMTA1 is a useful immunohistochemical marker for diagnosing epithelioid hemangioendothelioma. Histopathology 2015 Apr; doi 10.1111/his.12713.

Contributed by:
Nafis Shafizadeh, MD
Southern California Permanente Medical Group

Woodland Hills Medical Center


Interesting Case June 2015 #2

Case History: 

A 62 year old woman with a history of renal cell carcinoma removed years ago presented with a 2.4 cm liver mass found in CT during follow-up. A partial hepatectomy was performed.

Laboratory values: 

ALT, AST, alkaline phosphatase and bilirubin were normal. There is no prior history of liver disease.

Gross examination of the liver resection: 

Cut section reveals a 2.4 cm circumscribed mass with a gray-brown focally spongy appearance.


Figure 1

Figure 2

Figure 3, CD31 immunohistochemistry

Final diagnosis: 

Hemangioma, anastomosing type.

Discussion:

Hepatic hemangioma is a common benign vascular neoplasm in both infants and adults that shares the same growth pattern and prognosis as its cutaneous counterpart. Based on its distribution, hemangioma can be classified as focal, multifocal, or diffuse.  Most hepatic hemangiomas are of the cavernous type followed by the capillary type. Capillary hemangioma, including lobular capillary hemangioma (also known as pyogenic granuloma) commonly presents on the skin and mucosa, although rare liver or gastrointestinal tract examples have been reported. Capillary hemangioma is composed of a lobular proliferation of vascular channels with plump endothelial cells lining the vascular channels. Anastomosing hemangiomas in the liver, as seen in this case, are rare hepatic vascular neoplasms characterized by an interconnecting sinusoidal-like pattern of tightly packed capillary channels. The tumor appears well circumscribed grossly with a gray-brown focally spongy appearance in the liver. Low-power magnification shows a well-demarcated lesion with lobular architecture in the liver. At higher magnification the tumors consists of anastomosing sinusoidal capillary-sized vessels with scattered hobnail endothelial cells within a framework of non-endothelial supporting cells. No mitotic figures or necrosis are observed. Mild cytologic atypia is appreciated. Immunohistochemical stain for CD31 is diffusely positive.

The primary differential diagnosis of anastomosing hemangioma is angiosarcoma. Angiosarcoma of the liver and gastrointestinal tract is rare and behaves aggressively. The overall survival is poor and patients rapidly develop metastases and usually die within 6–12 months. Accurate diagnosis can be challenging, particularly if the patients have no history of exposure to specific toxins including thorium dioxide, arsenicals, and vinyl chloride monomer. Distinguishing anastomosing hemangioma from a well-differentiated angiosarcoma is challenging especially on small biopsies. Histologically, branching, jagged, slit-like vascular channels with prominent cytological alterations and a diffuse infiltrating border is characteristic of angiosarcoma, in contrast to the sharp demarcation, mild cytological atypia, and lack of mitotic figures in anastomosing hemangioma. The absence of multilayering of endothelial cells, high grade cytologic atypia, and mitotic activity coupled with circumscribed borders favor a benign process. Awareness of this entity and attention to cytological features and the overall lobular architecture are essential to avoid diagnostic errors.

In summary, anastomosing hemangiomas in the liver is a rare entity and leads to concern for angiosarcoma. Awareness of this entity can minimize a misdiagnosis of angiosarcoma and avoid unnecessary aggressive treatment.

References 

1. Kulungowski AM, Alomari AI, Chawla A, Christison-Lagay ER, Fishman SJ. Lessons from a liver hemangioma registry: subtype classification. J Pediatr Surg. Jan 2012;47(1):165-170. 
2. Dickie B, Dasgupta R, Nair R, et al. Spectrum of hepatic hemangiomas: management and outcome. J Pediatr Surg. Jan 2009;44(1):125-133. 
3. Abaalkhail F, Castonguay M, Driman DK, Parfitt J, Marotta P. Lobular capillary hemangioma of the liver. Hepatobiliary Pancreat Dis Int. Jun 2009;8(3):323-325. 
4. Nishiyama N, Mori H, Kobara H, et al. Bleeding duodenal hemangioma: morphological changes and endoscopic mucosal resection. World journal of gastroenterology : WJG. Jun 14 2012;18(22):2872-2876. 
5. Giaccaglia V, Stefanuto A, Cavallotti C, Quintiliani A, Stipa F. Transanal excision of rectal pyogenic granuloma: case report and literature review. Surg Laparosc Endosc Percutan Tech. Apr 2011;21(2):e91-92. 
6. Santos J, Ruiz-Tovar J, Lopez A, Arroyo A, Calpena R. Simultaneous massive low gastrointestinal bleeding and hemoperitoneum caused by a capillary hemangioma in ileocecal valve. International journal of colorectal disease. Oct 2011;26(10):1363-1364. 
7. Nagoya H, Tanaka S, Tatsuguchi A, et al. Rare cause of obscure gastrointestinal bleeding due to pyogenic granuloma in the ileum detected by capsule endoscopy and treated with double balloon endoscopy. Dig Endosc. Jan 2010;22(1):71-73. 
8. Park SY, Park CH, Lee WS, Kim HS, Choi SK, Rew JS. Pyogenic granuloma of the duodenum treated successfully by endoscopic mucosal resection. Gut Liver. Mar 2009;3(1):48-51. 
9. Shibuya T, Osada T, Mitomi H, et al. Jejunal capillary hemangioma treated by using double-balloon endoscopy (with video). Gastrointest Endosc. Sep 2010;72(3):660-661. 
10. Benevento A, Boni L, Dionigi G, Besana Ciani I, Danese E, Dionigi R. Multiple hemangiomas of the appendix and liver. J Am Coll Surg. Nov 2003;197(5):860-861. 
11. Lin J, Bigge J, Ulbright TM, Montgomery E. Anastomosing hemangioma of the liver and gastrointestinal tract: an unusual variant histologically mimicking angiosarcoma. The American journal of surgical pathology. Nov 2013;37(11):1761-1765. 
12. Brown CJ, Falck VG, MacLean A. Angiosarcoma of the colon and rectum: report of a case and review of the literature. Diseases of the colon and rectum. Dec 2004;47(12):2202-2207. 
13. Maluf D, Cotterell A, Clark B, Stravitz T, Kauffman HM, Fisher RA. Hepatic angiosarcoma and liver transplantation: case report and literature review. Transplantation proceedings. Jun 2005;37(5):2195-2199. 
14. Alrenga DP. Primary angiosarcoma of the liver. Review article. Int Surg. Apr 1975;60(4):198-203. 
15. Elliott P, Kleinschmidt I. Angiosarcoma of the liver in Great Britain in proximity to vinyl chloride sites. Occupational and environmental medicine. Jan 1997;54(1):14-18. 
16. Bhati CS, Bhatt AN, Starkey G, Hubscher SG, Bramhall SR. Acute liver failure due to primary angiosarcoma: A Case Report and Review of the Literature. World J of Surg Oncol. 2008;6:104.


Contributed by:
Jingmei Lin, MD, PhD
Department of Pathology and Laboratory Medicine
Indiana University School of Medicine