cis-Diamminedichloroplatinum-induced hypomagnesemia and renal magnesium wasting

Hypomagnesemia is a well-recognised complication of cis-diamminedichloroplatinum (DDP) treatment. We prospectively evaluated 50 patients with advanced malignant disease receiving DDP for the development of hypomagnesemia. Urinary magnesium excretion was measured in 24 patients. The mean serum magnesium fell from 0.79 mmol/l (normal 0.7-1.1 mmol/l) prior to therapy to 0.55 mmol/l 3 months after commencing DDP. All 50 patients had become hypomagnesemic by this time and 10% were symptomatic, requiring oral magnesium supplementation. At 6 weeks after commencing DDP only four patients had restricted urinary magnesium excretion to less than 1.0 mmol/day. The other patients clearly had inappropriately high levels of urinary magnesium excretion, suggesting that DDP may induce a renal tubular defect in magnesium conservation. Hypomagnesemia is a common complication of DDP therapy which in many patients is asymptomatic. Further, more detailed studies of renal magnesium handling are necessary to determine fully the effect of DDP on urinary magnesium excretion.

Randomized trial of combination chemotherapy in hormone-resistant metastatic prostate carcinoma

A prospective randomized study was conducted in 51 patients with stage D hormone-resistant prostatic carcinoma, comparing a combination of doxorubicin and lomustine (DC) with cyclophosphamide and 5-FU (CF). Patients were assessed objectively (employing National Prostate Cancer Project criteria) and subjectively (using a numerical scoring scheme). Each regimen was well tolerated with acceptable levels of myelosuppression. The objective partial response rate was 57% for DC and 8% for CF. Objective stabilization occurred, respectively, in 14% and 44% of the patients. Similarly, DC demonstrated a significantly superior subjective response rate (partial plus complete) of 82%, compared to 48% for CF. Patients with poor initial performance status or liver involvement had significantly lower response rates and reduced survival. Overall, there was no significant difference in survival between the two arms, reflecting the similarity between DC and CF in total objective response rate (partial response plus stable disease). DC provided superior palliation and was well tolerated by an essentially geriatric population.

Acute reduction of plasma vasopressin levels by rehydration in sheep

Sheep were depleted of water by restricting water intake to 500 ml/day for 7-9 days and were then rehydrated by three treatments: voluntary intake of water, administration of water by tube into the stomach, or voluntary intake of 0.9% NaCl solution (saline). The volumes of fluids drunk within 2-3 min, or administered by tube, were approximately equal to the animal's weight loss. Plasma vasopressin rose from 4.4 +/- 0.6 to 16.8 +/- 1.0 pg/ml during water restriction. After drinking water plasma vasopressin fell from 19.0 +/- 1.9 to 7.5 +/- 0.4 pg/ml (P less than 0.001) in 15 min and gradually fell to 3.2 +/- 0.4 pg/ml over 6 h. Plasma osmolality fell from 302.4 +/- 0.9 to 301.0 +/- 1.1 mosmol/kg (NS) 15 min after water drinking and then gradually fell to subnormal levels. Sheep given water by stomach tube showed a similar decline in plasma osmolality, but the fall in plasma vasopressin was attenuated. The fall in plasma vasopressin in the first 30 min after drinking saline was almost identical with the fall after drinking water, but plasma osmolality was unaltered. Plasma vasopressin fell so rapidly after drinking water or saline as to suggest that the act of drinking caused almost complete inhibition of vasopressin release without a change in plasma osmolality. The results are consistent with earlier evidence that oropharyngeal receptors initiate the inhibition of vasopressin release after drinking.

Treatment of advanced squamous-cell carcinoma of the head and neck with a combination of cisplatin, vinblastine, and bleomycin

Fifty patients with advanced, measurable, squamous-cell cancers of the head and neck received treatment with a combination of cisplatin, vinblastine, and bleomycin (PVB). The tumours in 25 patients (50%) responded to treatment (partially in 17 and completely in eight). The median duration of response was 18 weeks, and that of survival was 31 weeks. Toxicity was moderately severe; myelotoxicity occurred in 13 patients, and nausea and vomiting in 22 patients.

A histologic comparison of Hydron and zinc oxide-eugenol as endodontic filling materials in the primary teeth of dogs

Currently available endodontic filling materials for primary teeth demonstrate several inadequacies. Therefore, this study histologically evaluates Hydron (2-hydroxyethylmethacrylate) and zinc oxide and eugenol (ZOE) as primary tooth endodontic filling materials in dogs to compare the materials' biocompatibility and to determine whether they undergo resorption in a physiologic manner. Primary molars of six mongrel dogs, 2 to 3 months old, received one-step endodontic therapy. By random selection, two thirds of the molars were filled with either Hydron or ZOE and the remainder were used as unoperated controls. Block sections taken during physiologic root resorption were used to obtain serial hematoxylin and eosin sections of periapical regions. Hydron was phagocytosed by mononuclear macrophages in a physiologic manner and at a rate comparable to that of root tissues. In contrast, ZOE demonstrated delayed resorption and transitory inflammation. Neither material showed cytotoxicity. Hydron may therefore be a suitable endodontic material for human primary teeth.

Mitolactol chemotherapy for malignant melanoma: a phase II study

Fifty-one patients (43 evaluable) with malignant melanoma were treated with mitolactol in an intermittent oral schedule. There were four objective tumor responses, all occurring in patients previously treated with dacarbazine.

Bleomycin pulmonary toxicity: its relationship to renal dysfunction

Two hundred seventy-five patients who had received bleomycin were examined for evidence of pulmonary toxicity. Twenty-six patients were diagnosed as having bleomycin pulmonary toxicity and, of these, 20 (77%) were documented as having renal dysfunction without other features recognized to be associated with the development of pulmonary toxicity. In this study renal dysfunction was a most important factor in the development of bleomycin pulmonary toxicity. As bleomycin is often administered with nephrotoxic drugs, it is suggested that renal function should be checked prior to each administration of bleomycin. It is proposed that appropriate dose modifications could significantly reduce the morbidity and mortality associated with bleomycin administration.

The role of hepatitis B virus in the etiology of hepatocellular carcinoma in Australia

Fifty-three patients with Hepatocellular Carcinoma (HCC) from three Sydney teaching hospitals were examined for possible evidence of Hepatitis B virus (HBV) infection. Hepatitis Surface Antigen (HBsAg) was positive in 38% of those in whom it was sought, a higher incidence than previously reported in an Australian series. A further 13 patients had antibody to Hepatitis B core (Anti-HBc), but negative HBsAg, confirming past exposure to HBV. Where serum was available evidence of HBV infection was obtained in 62% of patients. It is argued that the incidence of HBV infection may be shown to be higher still with the advent of new technology as applied to HBV assays and tissue stains. The need to be aware of the growing evidence of a strong association between Hepatitis B virus and the development of HCC is stressed and the clinical implications are discussed.

Contribution of vasopressin to the maintenance of blood pressure during dehydration

Normal Long-Evans rats, when dehydrated for up to 72 h, have a progressive rise in plasma vasopressin that is associated with a fall in body weight and urine volume, a rise in plasma and urine osmolality, and the maintenance of normal systolic blood pressure. In contrast, Brattleboro diabetes insipidus rats, genetically deficient in vasopressin, when dehydrated to achieve an equivalent body weight loss, have a significant 15 mmHg fall in systolic blood pressure. Even when fluid balance is corrected in the Brattleboro rats by the continuous administration of 1-desamino-8-D-arginine vasopressin, a synthetic vasopressin analogue with potent antidiuretic properties but minimal pressor activity, blood pressure still falls when the animals are dehydrated. In contrast, Brattleboro rats infused with exogenous arginine vasopressin to produce a plasma vasopressin level of 18.9 +/- 3.5 pg X ml-1 are able to maintain normal blood pressure during 48 h of dehydration. This level of vasopressin is comparable to the level found endogenously in dehydrated Long-Evans rats and is nonpressor in normal rats. These results suggest that both the antidiuretic and vasoconstrictor properties of vasopressin are important in the cardiovascular response to dehydration.

On the receiving end--II. Linear analogue self-assessment (LASA) in evaluation of aspects of the quality of life of cancer patients receiving therapy

Linear analogue self-assessment (LASA) scales were used to measure general well-being and specific factors (mood, pain, nausea and vomiting, appetite, breathlessness, physical activity) in patients receiving therapy for malignant melanoma, small cell bronchogenic carcinoma (SCBC) or ovarian cancer. Among the patients with SCBC and melanoma, high correlations were observed between LASA scores for general well-being, mood and appetite. There was a significant relationship between performance status and LASA scores for general well-being, pain and appetite. Among patients with ovarian cancer, there was a significant association between performance status and LASA scores for general well-being, breathlessness and physical activity. Objective response category was related to change in LASA scores for pain. Changes in LASA scores during treatment reflected increased morbidity during radiotherapy in patients also receiving chemotherapy for SCBC. The LASA technique provides a convenient method for the assessment of quality of life in patients receiving cancer therapy, and potentially allows comparison of patient perception of treatment-related morbidities.

Surgery in patients with advanced germ cell malignancy following a clinical partial response to chemotherapy

Twenty-one patients with metastatic germ cell tumors achieved only partial clinical tumor regression following chemotherapy, and underwent surgical biopsy or resection of the residual tumor deposits. Sixteen (76%) are at present clinically disease-free after a median 30 + months (range 17-50 months) from the time of surgery, and five (24%) died after 9-29 months. Adverse prognostic signs were the finding of persistent cancer at histopathological examination of the resected tumor masses, and the presence of elevated serum tumor markers at the time of surgery. Postchemotherapy surgery in this setting provides tissue for the prognostically important histopathological examination on which a decision regarding further chemotherapy may be based. In addition, it provides tumor bulk reduction in the cases of differentiated teratoma and persistent cancer.

Malignant hypertension in Brattleboro (vasopressin-deficient) rats

The role of arginine vasopressin (AVP) in malignant renal hypertension was investigated using the homozygous Brattleboro (vasopressin-deficient) rat. Brattleboro rats with complete aortic-ligature between the renal arteries developed malignant hypertension with the same frequency and severity as normal Long-Evans rats subjected to the same procedure. The Long-Evans hypertensive rats had significantly elevated plasma AVP levels. Plasma renin activity and plasma angiotensin II levels were significantly elevated in both Brattleboro and Long-Evans rats with malignant hypertension and the levels reached were equivalent in both groups. Thus, the renin-angiotensin system did not compensate for the lack of AVP in malignant hypertensive Brattleboro rats. Specific vascular lesions of fibrinoid necrosis were observed in a high percentage of rats with malignant hypertension, in both the Brattleboro and Long-Evans strains. We conclude that AVP does not play a primary role in the pathogenesis of malignant renal hypertension and, in particular, in the development of the vascular lesions of fibrinoid necrosis.

Use of aminoglutethimide as second-line endocrine therapy in metastatic breast cancer

Sixty-five patients with advanced breast cancer, progressive despite prior endocrine therapy in all cases and prior chemotherapy in most cases, were treated with aminoglutethimide, 250 mg four times a day. At present, 52 are evaluable for response assessment, and of these 10 (19%) showed an overall objective response, major sites of response being soft tissue and lung. A further 12 patients (23%) had stable disease during aminoglutethimide therapy, while a total of 9 patients with bone metastases reported marked relief of pain without objective evidence of response. Forty-nine patients had received prior treatment with tamoxifen, and of the 10 tamoxifen responders 4 (40%) responded to subsequent aminoglutethimide, while of the 20 tamoxifen failures only 2 (10%) responded to subsequent aminoglutethimide. Aminoglutethimide was reasonably well tolerated, although 6 patients (0%) discontinued treatment because of intolerable side effects. Six of the 10 responding patients have subsequently relapsed, with a mean duration of response of 17 weeks, but 4 continued to respond at 24, 32, 55, and 111 weeks, respectively. The median survival from the start of aminoglutethimide therapy is in excess of 41 weeks for responders and 11 weeks for nonresponders, while the median survival from first relapse is 48 months for aminoglutethimide responders and 28 months for aminoglutethimide nonresponders. These results confirm that aminoglutethimide can offer a useful alternative form of endocrine therapy for advanced breast cancer, but the response rates obtained in heavily pretreated patients are inferior to those obtained when aminoglutethimide is used earlier in sequential treatment. For optimal results, particularly in terms of quality of life, aminoglutethimide should generally be used prior to chemotherapy.

Four-drug combination chemotherapy for advanced cervical carcinoma

Thirty-one patients with advanced stage squamous cell carcinoma of the cervix were treated with the four-drug combination fluorouracil, doxorubicin, cyclophosphamide, and vincristine. Four patients achieved complete remission (13%) and 15 partial remission (45%). The only factor of adverse prognostic significance was poor initial patient performance. Median survival for the patients entering complete remission exceeded 54 weeks and was 43 weeks for patients achieving partial remission. Seven patients are still alive at 50 weeks. This represents a notable prolongation of survival compared with those patients who did not achieve remission. Toxicity for the combination was not excessive; myelosuppression and vincristine-induced neuropathy were the most prominent. These results are moderately encouraging and confirm the sensitivity of cervical carcinoma to systemic chemotherapy. Further studies to define the optimal use of chemotherapy in both advanced and earlier stages of disease are warranted.

Advanced ovarian cancer: a prospective randomised trial of chlorambucil versus combined cyclophosphamide and cis-diamminedichloroplatinum

Thirty-seven patients with advanced ovarian cancer were treated in a prospective, randomised trial comparing chlorambucil with a combination of cyclophosphamide and cis-diamminedichloroplatinum (cis DDP). Treatment with the combination was associated with an increased overall response rate (69% versus 23%) (p = 0.04). A response was associated with a longer median survival but no survival advantage was demonstrated for patients who received cyclophosphamide/cis DDP. A larger study is needed to evaluate fully the potential of regimens containing cis DDP in the management of advanced ovarian cancer.

Role of vasopressin in hypertension: studies using the Brattleboro rat

Plasma arginine vasopressin (AVP) levels were elevated in both one-kidney, one-clip [1K-1C) and two-kidney, one-clip (2K-1C) hypertensive Long-Evans rats. Homozygous Brattleboro rats with hereditary hypothalamic diabetes insipidus (DI), which are completely devoid of vasopressin, were made hypertensive using the 1K-1C Goldblatt models for renal hypertension. The 2K-1C DI rats developed hypertension at the same rate and to the same degree as normal 2K-1C hypertensive Long-Evans rats. The development of hypertension in 1K-1C DI rats was similar to the normal 1K-1C hypertensive Long-Evans rats. However, the absolute levels of systolic blood pressure reached were significantly less in the vasopressin-deficient rats. Treatment with 1-desamino-8-D-arginine vasopressin (DDAVP), the synthetic analogue of arginine vasopressin that has high antidiuretic but low pressor potencies, was associated with restoration of water balance in the volume-depleted DI rats and also restored blood pressure to hypertensive levels equivalent to the 1K-1C Long-Evans rats. These studies suggest that vasopressin is not essential for the development of experimental renal hypertension in rats but may contribute to the absolute levels of systolic blood pressure reached through its properties as an antidiuretic hormone.

Vascular lesions and angiotensin in malignant hypertension in the absence of vasopressin

1. Vasopressin deficient homozygous Brattleboro rats develop malignant renal hypertension following complete aortic-ligature between the renal arteries. 2. This form of hypertension is associated with high plasma renin activity (PRA) and plasma angiotensin II (AII) levels and a high incidence of the specific vascular lesions of fibrinoid necrosis in both Brattleboro and Long-Evans rats. 3. The levels of PRA and AII in the malignant hypertensive Brattleboro rats were not different from those in Long-Evans rats with malignant hypertension. 4. No compensation by the renin-angiotensin system therefore could be demonstrated for the lack of vasopressin in malignant hypertensive Brattleboro rats. 5. Vasopressin does not appear to be essential as a pressor hormone in the development of malignant renal hypertension and fibrinoid can occur in the absence of vasopressin.

Phase II study of doxorubicin and mitomycin in non-small cell bronchogenic carcinoma

Thirty patients with advanced measurable non-small cell bronchogenic carcinoma were treated with a combination of doxorubicin (50 mg/m2 every 3 weeks) and mitomycin (20 mg/m2 every 6 weeks). One complete and three partial responses were observed. This response rate is similar to that reported for either drug used alone.

Importance of antidiuretic properties of vasopressin in experimental renal hypertension

1. Homozygous Brattleboro rats with hereditary hypothalamic diabetes insipidus (DI) developed one-kidney, one-clip (1K-1C) and two-kidney, one-clip (2K-1C) Goldblatt renal hypertension. 2. However, the systolic blood pressure (SBP) in 1K-1C Brattleboro rats was significantly lower than in non-DI hypertensive 1K-1C Long-Evans (LE) rats. 3. Treatment with the synthetic antidiuretic analogue of vasopressin, DDAVP (1-desamino-8-D-arginine vasopressin), increased the SBP in the DI rats to the same level as in 1K-1C Long-Evans. This elevation of SBP was associated with increased extracellular fluid volume in the DI rats after DDAVP. 4. The results suggest that vasopressin is not essential for the development of renal hypertension but the absolute levels of blood pressure achieved in 1K-1C hypertension are volume-dependent and thus influenced by the water-retaining properties of vasopressin.

The treatment of metastatic breast cancer with aminoglutethimide

Thirty-eight patients with advanced breast cancer, resistant to prior endocrine therapy and in most cases prior chemotherapy, were treated with aminoglutethimide, 250 mg qds. Seven of 30 evaluable patients (23%) responded. Six have subsequently relapsed with a mean duration of response of 17 weeks, while one continues to respond after 50 weeks of therapy. Six additional patients (20%) had stable disease during aminoglutethimide therapy (mean duration of 16 weeks). Three of the seven responders had shown a partial response, two had stable disease and two had progressive disease on prior endocrine therapy (including tamoxifen); six of the seven patients responding to aminoglutethimide had received prior combination chemotherapy, to which all had responded. Aminoglutethimide was generally well tolerated, although three patients withdrew from treatment within the first two weeks because of intolerable drowsiness. Aminoglutethimide offers a useful alternative to surgical adrenalectomy for women with advanced breast cancer responsive to previous endocrine and cytotoxic chemotherapy.

Allopurinol modulation of fluorouracil toxicity

Considerable interest has developed in the modulation of fluorouracil activity by nucleosides. The toxicity of fluorouracil in mice is known to be reduced by concurrent administration of allopurinol, presumably because biochemical pathways activating fluorouracil in normal tissues are blocked. We have given allopurinol (300 mg t.d.s. PO) concurrently with continuous infusions of fluorouracil (2.0--2.25 g/m2/day X 5) to 34 patients with colorectal cancer and 11 patients with various adenocarcinomas. There were 41 patients assessable for toxicity. Stomatitis was the predominant dose-limiting toxicity (22% grade 1, 19% grade 2, and 27% grade 3 toxicity). Neutropenia (Less Than 1,000/mu l) occurred in 17% patients. Among 26 colorectal cancer patients assessable for response there was a 15.4% response rate. We conclude that allopurinol modulates fluorouracil toxicity in man, allowing a two-fold increase in dose. However, at least in colorectal cancer no greater frequency of tumour response is seen than with lower doses of fluorouracil given by standard schedules of administration without allopurinol.