Humoral hypercalcemia of malignancy with elevated plasma PTHrP, TNF alpha and IL-6 in cutaneous squamous cell carcinoma

Paraneoplastic Syndromes in Patients with Keratinocyte Skin Cancer

Simple Summary

The aim of the present review is to compile and evaluate the literature data on paraneoplastic syndromes (PNS) associated with keratinocyte skin cancer (KSC). Forty relevant entries were assembled, reporting a total of 41 PNS cases associated with a KSC (34 male). No review paper compiling this topic was found. Six distinct PNS entities were identified, and malignancy associated hypercalcemia (MAH; 78%), anemia (10%) and Bazex syndrome (5%) were the most frequently reported among them. 85% of the PNS were reported in association with SCC, 10% with BCC, and the rest with adnexal tumors. The median age of the patients at the time of PNS diagnosis was 58 years (range: five–83 years). KSC predisposing conditions, as scars (22%) or hidradenitis suppurativa (20%), were reported in >70% of the PNS cases. In conclusion, PNS are rarely reported in association with KSC, possibly reflecting a limited capacity of KSC to provoke overt PNS.

Abstract

A variety of well-characterized cutaneous paraneoplastic syndromes (PNS) are diagnosed during internal malignancies; however, the spectrum of keratinocyte skin neoplasms (KSC) related to PNS is still obscure. The aim of the present review is to compile and evaluate the literature data on PNS associated with a keratinocyte skin neoplasm (KSC). Employing Pubmed, MEDLINE was searched for KSC-associated PNS reports. Forty relevant entries were assembled, reporting a total of 41 PNS cases associated with a KSC (34 male). No review paper compiling this topic was found. Six distinct PNS entities were identified, and malignancy associated hypercalcemia (MAH; 78%), anemia (10%) and Bazex syndrome (5%) were the most frequently reported among them. 85% of the PNS were reported in association with SCC, 10% with BCC, and the rest with adnexal tumors. The median age of the patients at the time of PNS diagnosis was 58 years (range: five–83 years). In most cases the PNS was diagnosed either concurrently or after the KSC diagnosis. KSC predisposing conditions, as scars (22%) or hidradenitis suppurativa (20%), were reported in >70% of the PNS cases. Most PNS resolved after KSC treatment. In conclusion, PNS of a rather limited spectrum of entities are reported in association with KSC. They also seem to be rare, possibly reflecting a limited capacity of KSC to provoke overt PNS.

Zoledronate-responsive calcitriol-mediated hypercalcemia in a 5-year-old case with squamous cell carcinoma on the background of xeroderma pigmentosum

Malignancy-induced hypercalcemia is a very rare condition in children whereas it is more common among adult patients with malignancy. The mechanisms of malignancy-induced hypercalcemia include the over-secretion of parathyroid hormone-related protein (PTHrP), osteolytic metastases and the over-production of 1,25-dihydroxyvitamin D (calcitriol). Although hypercalcemia due to PTHrP secretion has been published before, overproduction of calcitriol has not been reported yet in pediatric squamous cell skin carcinoma cases. Herein, we report calcitriol-mediated severe hypercalcemia in a 5-year-old boy with squamous cell skin carcinoma arising in the background of xeroderma pigmentosum (XP) which responded well to zoledronate treatment. To the best of our knowledge, this is the first pediatric case of malignancy-induced hypercalcemia which is mediated by calcitriol in squamous cell skin carcinoma.

Animal Models of Cancer-Associated Hypercalcemia

Cancer-associated hypercalcemia (CAH) is a frequently-occurring paraneoplastic syndrome that contributes to substantial patient morbidity and occurs in both humans and animals. Patients with CAH are often characterized by markedly elevated serum calcium concentrations that result in a range of clinical symptoms involving the nervous, gastrointestinal and urinary systems. CAH is caused by two principle mechanisms; humorally-mediated and/or through local osteolytic bone metastasis resulting in excessive calcium release from resorbed bone. Humoral hypercalcemia of malignancy (HHM) is the most common mechanism and is due to the production and release of tumor-associated cytokines and humoral factors, such as parathyroid hormone-related protein (PTHrP), that act at distant sites to increase serum calcium concentrations. Local osteolytic hypercalcemia (LOH) occurs when primary or metastatic bone tumors act locally by releasing factors that stimulate osteoclast activity and bone resorption. LOH is a less frequent cause of CAH and in some cases can induce hypercalcemia in concert with HHM. Rarely, ectopic production of parathyroid hormone has been described. PTHrP-mediated hypercalcemia is the most common mechanism of CAH in human and canine malignancies and is recognized in other domestic species. Spontaneous and experimentally-induced animal models have been developed to study the mechanisms of CAH. These models have been essential for the evaluation of novel approaches and adjuvant therapies to manage CAH. This review will highlight the comparative aspects of CAH in humans and animals with a discussion of the available animal models used to study the pathogenesis of this important clinical syndrome.

Hypercalcemia of Malignancy in Thymic Carcinoma: Evolving Mechanisms of Hypercalcemia and Targeted Therapies

Here we describe, to our knowledge, the first case where an evolution of mechanisms responsible for hypercalcemia occurred in undifferentiated thymic carcinoma and discuss specific management strategies for hypercalcemia of malignancy (HCM). Case Description. We report a 26-year-old male with newly diagnosed undifferentiated thymic carcinoma associated with HCM. Osteolytic metastasis-related hypercalcemia was presumed to be the etiology of hypercalcemia that responded to intravenous hydration and bisphosphonate therapy. Subsequently, refractory hypercalcemia persisted despite the administration of bisphosphonates and denosumab indicative of refractory hypercalcemia. Elevated 1,25-dihydroxyvitamin D was noted from the second admission with hypercalcemia responding to glucocorticoid administration. A subsequent PTHrP was also elevated, further supporting multiple mechanistic evolution of HCM. The different mechanisms of HCM are summarized with the role of tailoring therapies based on the particular mechanism underlying hypercalcemia discussed. Conclusion. Our case illustrates the importance of a comprehensive initial evaluation and reevaluation of all identifiable mechanisms of HCM, especially in the setting of recurrent and refractory hypercalcemia. Knowledge of the known and possible evolution of the underlying mechanisms for HCM is important for application of specific therapies that target those mechanisms. Specific targeting therapies to the underlying mechanisms for HCM could positively affect patient outcomes.

A Male Patient with Humoral Hypercalcemia of Malignancy (HHM) with Leukocytosis Caused by Cutaneous Squamous Cell Carcinoma Resulting from Recessive Dystrophic Epidermolysis Bullosa

Recessive dystrophic epidermolysis bullosa (RDEB) is a severe skin disorder. Although the patients are at risk for cutaneous squamous cell carcinoma (SCC), no case of cutaneous SCC derived from RDEB with humoral hypercalcemia of malignancy (HHM) has been reported. We present the first case report of a male patient with HHM with leukocytosis caused by cutaneous SCC resulting from RDEB. A 20-yr-old Japanese male patient with RDEB; the diagnosis was confirmed by electron microscopic examination, suffered an intractable skin ulcer and hypercalcemia and leukocytosis. PTH-rP, SCC antigen and Granulocyte colony-stimulating factor (G-CSF) levels were elevated. The histological diagnosis of the skin lesion was made well-differentiated SCC. Immunohistochemical staining showed the expression of PTH-rP in atypical tumor cells. For the control of hypercalcemia before an amputation, we used zoledronate safely and could control the serum Ca concentration in the normal range. After the amputation of his right leg including SCC, leukocytosis improved immediately and PTH-rP in blood decreased to the normal range. One month after the amputation, local recurrence of cutaneous SCC and multiple lung metastases were observed. PTH-rP increased gradually associated with hypercalcemia. Although the patient reached an unfortunate turning point about 4 mo after the amputation, we propose that zoledronate is an effective and safe treatment for HHM with cardiorenal complications.

Hypercalcemia in a patient with renal cell carcinoma producing parathyroid hormone-related protein and interleukin-6

A patient with renal cell carcinoma who developed humoral hypercalcemia of malignancy is reported. A 52-year-old male patient was diagnosed with renal cell carcinoma and multiple lung metastases. A cell line isolated from the surgical specimen exhibited continuous production of parathyroid hormone-related protein (PTHrP) in vitro. The production of PTHrP from the cancer cells was confirmed by RT-PCR and immunoradiometric assay. The serum calcium level was not enhanced, whereas the lung lesion was developing and producing interleukin-6, a possible modulator of osteoclastic resorption. Hypercalcemia was induced when the PTHrP concentration increased up to 3.3 pmol/L.

Cancer cells responsible for humoral hypercalcemia express mRNA encoding a secreted form of ODF/TRANCE that induces osteoclast formation

A novel cDNA encoding a secreted form of osteoclast differentiation factor/tumor necrosis factor-related activation-induced cytokine (sODF/TRANCE, GenBank Accession No. AB037599) was sequenced from 5' RACE cDNA clones of squamous cell carcinoma cell lines, SCC-4 and T3M-1 Cl.2, of which parental malignant tissues had caused severe humoral hypercalcemia. The sODF/TRANCE cDNA was composed of unknown 5' end sequence followed by the 100% identical sequence of the ODF/TRANCE extracellular domain-coding region. The longest open reading frame (ORF) of the novel cDNA completely matched the 3' end of the ORF of the ODF/TRANCE cDNA encoding C-terminal amino acid residues (74-318) in the extracellular region. The corresponding protein that reacted with the antibody specific for the extracellular domain of ODF/TRANCE was detected in the culture media conditioned by the cancer cells. Furthermore, human promyeloblastic leukemia cells, HL60, differentiated into osteoclast-like cells (OCLs) when cultured in the media conditioned by SCC-4 and T3M-1 Cl. 2 cells. The differentiation of HL60 cells into OCLs was inhibited by the anti-ODF/TRANCE antibody. These results strongly suggest that sODF/TRANCE plays an important role in enhanced bone-resorption in humoral hypercalcemia of malignancy.