Paraneoplastic leukemoid reaction (PLR) is the extreme leukocytosis that occurs due to a non-haematolymphoid cytokine-secreting tumour (CST) in the absence of bone marrow infiltration by that solid tumour. The clinical presentation is widely variable, and therefore challenging. If the underlying malignancy is not clinically apparent, PLR could be mistaken for myeloproliferative neoplasms, altering the patient’s management. CSTs are highly aggressive tumours associated with a poor prognosis due to multiple mechanisms. Localising and treating the underlying malignancy is the mainstay of treatment. Both the treating clinician and the pathologist should keep a high level of suspicion for this entity in patients having unexplained leukocytosis. We herein discuss the underlying mechanisms, clinical presentation, pathological features, differential diagnosis and prognosis of this rare entity. An emphasis on the role of the pathologist is provided since the lack of knowledge on this entity can lead to dramatic effects on the patient, including unnecessary diagnostic testing and treatments.

No abstract

No abstract

Objective: We sought to characterize clinical and pathologic outcomes of advanced mixed germ cell tumors after retroperitoneal lymph node dissection for post-chemotherapy residual masses. Material and methods:Between January 2006 and November 2015, 56 patients underwent retroperitoneal lymph node dissection (RPLND) for residual masses of greater than 1 cm after receiving either primary chemotherapy or salvage chemotherapy. Retrospective review of the patients' characteristics, clinical, pathological, and treatment outcomes were performed after institutional review board (IRB) and ethics committee approval. Results:The mean age at diagnosis was 30 years. Ninety percent of the patients received 3-4 cycles of BEP (bleomycin/etoposide/cisplatin) as primary chemotherapy, and 29% of them salvage chemotherapy prior to lymph node dissection. The mean size of the residual masses after chemotherapy was 6 cm. The histological findings were necrosis in 30%, viable tumor in 34% and teratoma in 36% of the retroperitoneal masses. The mean time to relapse after RPLND was 11 months, out of 9 relapses, 6 were in the retroperitoneum, 1 in the lung and 1 in the kidney and 1 in the contralateral testicle. Conclusion:Our results indicated higher incidence of viable germ cell tumor in the retroperitoneal residual masses after primary and salvage chemotherapy when compared with previously reported global incidence rates.