Histopathology of panniculitis--aspects of biopsy techniques and difficulties in diagnosis

A case report of pancreatic panniculitis due to acute pancreatitis with intraductal papillary mucinous neoplasm

BACKGROUND

Pancreatic panniculitis is a rare skin manifestation in pancreatic disease patients that most frequently develops on the lower legs. We report the unique case of a 68-year-old man who suffered from pancreatic panniculitis on his trunk associated with acute pancreatitis due to an intraductal papillary mucinous neoplasm.

CASE PRESENTATION

A 68-year-old man complained of a 2-day history of a tender subcutaneous nodule on his trunk. Laboratory tests and abdominal contrast computed tomography were consistent with acute pancreatitis due to an intraductal papillary mucinous neoplasm. A skin biopsy of the nodule histologically displayed lobular panniculitis with characteristic "ghost cells", which indicated pancreatic panniculitis.

CONCLUSIONS

In order to avoid a missed or delayed diagnosis, clinicians should bear in mind that pancreatic panniculitis can be the first manifestation of pancreatic disease when encountering subcutaneous nodules on the trunk.

[Differential diagnosis of panniculitides]

Panniculitides are diseases of the subcutaneous tissue with heterogeneous etiology. They may develop consequent to infections, as a reaction to drugs, after thermal injury, as part of autoimmune diseases, in metabolic disorders or due to infectious organisms. The clinical presentation with subcutaneous nodules is often nonspecific. Moreover, the differentiation from vasculitides of medium-sized vessels can be clinically challenging. Microscopic examination of biopsy specimens is of high importance in the differential diagnosis of panniculitides. Histopathologically, panniculitides can be classified according to the predominantly infiltrated area in septal and lobular panniculitides and they can be separated from vasculitides of medium-sized vessels. Diagnostic difficulties arise from inadequate biopsy specimens and from lack of clinicopathological correlation. This article summarizes diagnostic criteria of frequent and clinically important panniculitides.

Pancreatic panniculitis in a patient with pancreatic-type acinar cell carcinoma of the liver--case report and review of literature

Background

Pancreatic panniculitis is a rare condition, which has only been described in relation with pancreatic diseases up to now. It is characterized by necrotizing subcutaneous inflammation and is thought to be triggered by adipocyte necrosis due to systemic release of pancreatic enzymes with consecutive infiltration of neutrophils. We present the first case of a patient with pancreatic panniculitis caused by pancreatic-type primary acinar cell carcinoma (ACC) of the liver and without underlying pancreatic disease.

Case presentation

A 73-year old Caucasian female patient was referred to our department with painful cutaneous nodules persisting for eight weeks and with marked lipasemia (~15000 U/l; normal range <60 U/l). Four weeks prior, several liver lesions had been detected. Empiric treatment with steroids did not show any effect. A biopsy of the skin nodules revealed “pancreatic” panniculitis, while abdominal imaging with ultrasound, computed tomography and magnetic resonance imaging detected no abnormal pancreatic findings. Ultrasound-guided biopsy of the liver lesions showed infiltrates of an ACC. The patient died soon thereafter. Autopsy failed to reveal any other primary for the ACC, so that a pancreatic-type ACC of the liver was diagnosed by exclusion.

One hundred thirty cases of pancreatic panniculitis published within the last 20 years are reviewed. ACC of the pancreas is the most common underlying neoplastic condition. Patients with associated neoplasm are significantly older, take longer to be diagnosed and have higher lipase levels than patients with underlying pancreatitis.

Extrapancreatic pancreatic-type ACC is very rare, but shows the same biological features as ACC of the pancreas. It is believed to develop from metaplastic or ectopic pancreatic tissue. Up to now, no pancreatic panniculitis in extrapancreatic ACC has been described.

Conclusion

Pancreatic panniculitis should always be included in the differential diagnosis of lipolytic panniculitic lesions. It can be regarded as a facultative paraneoplastic phenomenon.

When suspected, a thorough work-up for identification of the underlying disease is mandatory and extrapancreatic lesions (e.g. liver) should also be considered. While administration of octreotide or steroids can sometimes alleviate symptoms, immediate treatment of the associated condition is the only effective management option.

[Subcutaneous panniculitis-like T-cell lymphoma : Two case reports]

Histopathology, immunohistochemical, and molecular genetic findings revealed the diagnosis of subcutaneous panniculitis-like T-cell-lymphoma in two patients, aged 44 and 70 years. The clinical morphology of the lymphoma manifestations showed varied significantly. One patient presented with a singular erythematous nodule in the chin region. The other patient suffered from extended plate-like resistances and atrophy of the face, upper arms and left breast. Hemophagocytic syndrome was not present in either patient. Prognosis of subcutaneous panniculitis-like T-cell lymphoma without associated hemophagocytic syndrome is reported to be favorable. Radiotherapy of the singular lesion on the chin and systemic corticosteroids of the extended plaques induced complete remission in both patients.