Case 1: This middle aged woman underwent mastectomy with axillary lymph node dissection for an infiltrating lobular carcinoma of the breast

http://pathology2.jhu.edu/jkronz/images/JMD 6-14-04 SPWC/Case 1/a.jpg

Your diagnosis:

Metastatic malignant melanoma

Blue nevus in a lymph node

Metastaic lobular carcinoma

Dermatopathic lymphadenopathy

Histologic description: Collections of pigmented cells, some of which demonstrate fine dendritic processes, are seen in the capsule and fibrous trabeculae of this axillary lymph node. The cells are not present in the sinus of the node.

Discussion: Nodal blue nevi have been recognized for decades. They are sometimes appreciated grossly as black streaks in the capsule of the lymph node. Microscopically heavily pigmented dendritic and bipolar cells are present in the capsule and intranodal fibrous trabeculae. Macrophages that have ingested pigment are also often present. Electron microscopy, if performed, will reveal mature melanosomes. Nodal blue nevi are entirely benign and should not be mistaken for metastatic malignant melanoma. The location of the pigmented cells in the capsule rather than the sinus of the node helps establish the correct diagnosis.

Reference: Epstein JI, Erlandson RA, Rosen PP. Nodal Blue Nevi, a study of Three Cases. Am J Surg Pathol. 1984; 8: 907-915

Case 2: This middle aged woman underwent a distal pancreatectomy and splenectomy for a serous cystadenoma of the pancreas. The lesion shown was in the pancreas, distal to (i.e. on the splenic side of) the serous cystadenoma of the pancreas.

http://pathology2.jhu.edu/jkronz/images/JMD 6-14-04 SPWC/Case 2/a.jpg

Your diagnosis:

Serous cystadenoma

Mucinous cystadenoma

Intraductal papillary mucinous neoplasm

Retention cyst

Histologic description:

These dilated pancreatic ducts are mostly lined by a low cuboidal to slightly columnar lining. Focally some of the cells are columnar and contain mucin. The surrounding stroma is relatively acellular.

Discussion: It can be difficult to distinguish between a retention cyst and an early intraductal papillary mucinous neoplasm (IPMN) of the pancreas. By definition, IPMNs involve the larger pancreatic ducts and are composed of tall columnar mucin-producing cells. These cells often form papillae. Retention cysts develop upstream from a site of obstruction of the pancreatic duct. Retention cysts are usually lined by attenuated, but otherwise normal ductal epithelium. In rare cases the epithelium lining a retention cyst is focally lined by a mucin-producing columnar epithelium. In these instances it can be extremely difficult to distinguish between IPMNs and retention cysts. Careful examination of the pancreatic duct is needed. If the duct is probe-patent, the lesion likely represents an early IPMN. In the case presented the duct was obstructed by the adjacent serous cystadenoma; hence, the lesion most likely represents a retention cyst which formed in the pancreas upstream of the obstructing tumor.

Case 3: This middle aged patent was found to have a large solid pancreatic mass.

http://pathology2.jhu.edu/jkronz/images/JMD 6-14-04 SPWC/Case 3/a.jpg

Your diagnosis:

Gastrointestinal stromal tumor (GIST)

Solitary fibrous tumor

Schwannoma

Spindle cell carcinoma of the pancreas

Histologic description: This spindle cell neoplasm closely abuts the pancreas and is relatively well-demarcated. The neoplasm shows less cellular areas with prominent collagenization and areas of increased cellularity. The neoplastic cells are cytologically bland and spindled with areas demonatrating a haphazard “patternless” pattern of growth with others showing a more pericytic pattern. The less cellular areas are admixed with keloid-like collagen. The vasculature shows an hemangiopericytic pattern with staghorn branching vessels.

Discussion: Solitary fibrous tumors were first described in the pleura, but have since been recognized throughout the body. By light microscopy they are composed of relatively uniform spindle shaped cells. The cells are admixed with keloid-like collagen, producing cellular and less cellular areas within the tumor. Hemangiopericytoma-like vessels are one of the most characteristic features of this neoplasm. When suspected, immunohistochemical labeling can help confirm the diagnosis. These neoplasms are CD34, bcl-2, factor XIIIa, and vimentin positive.

This case was kindly provided by Dr. Galen Cortina

Case 4: This woman in her 20’s had a cold nodule in her thyroid.

http://pathology2.jhu.edu/jkronz/images/JMD 6-14-04 SPWC/Case 4/a.jpg

Your diagnosis:

Reactive calcifications

Papillary carcinoma

Follicular carcinoma

Psammoma bodies highly suspicious for papillary carcinoma

Histologic description: Several psammoma bodies are present in the above section of thyroid (only one is shown). A mass is not present, and the surrounding thyroid epithelium is benign.

Discussion: Psammoma bodies in the thyroid, or for that matter anywhere in the head and neck region, should strongly suggest the presence of papillary thyroid carcinoma. Indeed, in this case, a small papillary carcinoma was found in an adjacent section of the thyroid. This case hits home that the top three diagnoses for psammoma bodies in the thyroid should be papillary carcinoma, papillary carcinoma, and papillary carcinoma; the discovery of psammoma bodies should prompt a diligent search for papillary carcinoma.

Case 5: This elderly alcoholic fell down the stairs and became acutely short of breath.

http://pathology2.jhu.edu/jkronz/images/JMD 6-14-04 SPWC/Case 5/a.jpg

Your diagnosis:

Pulmonary embolus from a deep venous thrombosis

Acute respiratory distress syndrome

Brain emboli to the lung

Disseminated intravascular coagulation

Histologic description: Multiple pulmonary arteries contain embolized pieces of histologically normal brain!

Discussion: Just about anything that enters the blood stream can embolize to the brain. In this case the severe head trauma experienced by this patient resulted in brain tissue being forced into the venous system. This brain tissue embolized to the lungs, ultimately killing the patient. A similar case has been reported in two lung transplant recipients. The donor had experienced severe head trauma prior to death, and, unbeknownst to the surgeons, brain tissue had embolized to the donor’s lungs. These brain emboli were transplanted along with the lungs.

Reference: Watanabe MA, Homma S, Schulman LL. Fatal cerebral emboli in two recipients of lung transplants from one donor. Transplantation, 75:2157-8, 2003.

This case was kindly provided by Dr. Grover Hutchins.

Case 6: This 50 some year old female had a liver transplant for primary sclerosing cholangitis. Months after transplant she developed signs and symptoms of biliary obstruction.

http://pathology2.jhu.edu/jkronz/images/JMD 6-14-04 SPWC/Case 6/a.jpg

Your diagnosis:

recurrent primary sclerosing cholangitis

traumatic neuroma obstructing the bile duct

granular cell tumor obstructing the bile duct

post-transplant lieomyosarcoma

Histologic description: The bile duct is surrounded and compressed by poorly organized bundles of nerve fibers.

Discussion: In this case a traumatic neuroma obstructing the bile duct clinically mimicked recurrent primary sclerosing cholangitis. When evaluating pathology from a transplant recipient, it can be useful to consider the timing of the pathology relative to the transplant. Common complications in the immediate post-transplant period include hyperacute rejection and surgical complications. Complications in the intermediate post-transplant period (weeks to months) include infection and rejection. Long-term (months to years) complications include chronic rejection and neoplasms (both post-transplant lymphoproliferative disorder and neoplasms that occur in the non-transplanted population).