Mohs micrographic surgery for male genital tumors: Local recurrence rates and patient-reported outcomes

BACKGROUND

Local recurrence rates (LRRs) after Mohs micrographic surgery (MMS) for male genital cancers have been reported in only a few small case series, and patient-reported outcomes (PROs) have not been studied.

OBJECTIVE

To determine the LRR and PROs after MMS for male genital skin cancers.

METHODS

Retrospective review of all male genital skin cancers removed with MMS between 2008 and 2019 at an academic center. LRR was determined by chart review and phone calls. PROs were assessed by survey.

RESULTS

A total of 119 skin cancers in 108 patients were removed with MMS. Tumors were located on the penis (90/119) and scrotum (29/119). Diagnoses included squamous cell carcinoma in situ (n = 71), invasive squamous cell carcinoma (n = 32), extramammary Paget disease (n = 13), melanoma (n = 2), and basal cell carcinoma (n = 1). The LRR was 0.84% (1/119), with a mean follow-up time of 3.25 years (median, 2.36 years). The majority of survey respondents reported no changes in urinary (66%) or sexual functioning (57.5%) after surgery.

LIMITATIONS

Retrospective single-center experience; short follow-up time; low survey response rate; no baseline functional data.

CONCLUSION

MMS for male genital skin cancer has a low LRR and high patient-reported satisfaction with urinary and sexual function.

L-Carnitine Reduces Muscle Cramps in Patients taking Vismodegib

Vismodegib is an oral, small-molecule hedgehog pathway inhibitor (HHI) approved for the treatment of locally advanced and metastatic basal cell carcinoma. While an effective treatment option for these conditions, HHI therapy is associated with muscle cramps in a significant number of patients. This adverse effect negatively impacts patient quality of life and patient adherence to the prescribed treatment regimen.Levocarnitine (L-carnitine) is a trimethylated amino acid known to play a critical role in lipid metabolism. It has antioxidant properties, and several studies have illustrated its effectiveness in lessening the severity of muscle cramps in various disease processes.We present three patients who developed muscle cramping associated with vismodegib treatment for basal cell carcinoma. Each was started on L-carnitine therapy, and all three reported a significant decrease in the severity of their muscle cramps to the point that they were able to continue HHI therapy without taking a drug holiday. These cases illustrate a promising treatment option for the most common side effect associated with HHI treatment. 

The discovery of a potent Nav1.3 inhibitor with good oral pharmacokinetics

In this article, we describe the discovery of an aryl ether series of potent and selective Na_v1.3 inhibitors. Based on structural analogy to a similar series of compounds we have previously shown bind to the domain IV voltage sensor region of Na_v channels, we propose this series binds in the same location. We describe the development of this series from a published starting point, highlighting key selectivity and potency data, and several studies designed to validate Na_v1.3 as a target for pain.

Managing peritoneal dialysis prescriptions

Current literature (Blake et al., 1996) suggests prescribing peritoneal dialysis based on individual characteristics and a sound knowledge of factors known to improve clearances. According to the CANUSA study (1996), better clearances are associated with a decreased relative risk of death, a decreased relative risk of technique failure and decreased hospitalization. This article will discuss factors which will improve clinical practice by prescribing peritoneal dialysis on an individualized basis leading to optimal patient outcome.

What is the optimal frequency of cycling in automated peritoneal dialysis?

OBJECTIVE

The recent increase in the use of automated peritoneal dialysis (APD) has led to concerns about the adequacy of clearances delivered by this modality. Few clinical studies looking at the effects of varying the individual components of the APD prescription on delivered clearance have been done, and most published data are derived from computer modeling. Most controversial is the optimal frequency of exchanges per APD session. Many centers prescribe 4 to 6 cycles per night but it is unclear if this is optimal. The purpose of this study was to address at what point the beneficial effect of more frequent cycles is outweighed by the concomitant increase in the proportion of the total cycling time spent draining and filling.

METHODS

A comparison was made between the urea and creatinine clearances (CCrs) achieved by 4 different APD prescriptions, used for 7 days each, in 18 patients. The prescriptions were for 9 hours each and were all based on 2-L dwell volumes, but differed in the frequency of exchanges. They were 5 x 2 L, 7 x 2 L, and 9 x 2 L, as well as a 50% tidal peritoneal dialysis (TPD) prescription using 14 L. Ultrafiltration, dwell time, glucose absorption, sodium and potassium removal, protein excretion, and relative cost were also compared. Clearances due to day dwells and residual renal function were not included in the calculation.

RESULTS

Mean urea clearances were 7.5, 8.6, 9.1, and 8.3 L/night for the four prescriptions respectively. Urea clearance with 9 x 2 L was significantly greater than with the other three prescriptions (p < 0 0.05). Urea clearance with 7 x 2 L and TPD were superior to 5 x 2 L (p < 0.05). Mean CCr was 5.1, 6.1, 6.4, and 5.6 L/night, respectively. Compared to 5 x 2-L, the 7 x 2-L, 9 x 2-L, and TPD prescriptions achieved greater CCr (p < 0.05). Taking both urea and CCr into account, 9 x 2 L was the optimal prescription in 12 of the 18 patients. Ultrafiltration and sodium and potassium removals were all significantly greater with the higher frequency prescriptions.

CONCLUSION

The 5 x 2-L prescription significantly underutilizes the potential of APD to deliver high clearances, and 7 x 2 L is a consistently superior prescription if 2-L dwells are being used. Although more costly, 9 x 2 L should be considered if higher clearances are required.

High creatinine excretion ratio predicts a good outcome in peritoneal dialysis patients

The creatinine excretion (CrEx) ratio was first described as a method for detecting noncompliance in peritoneal dialysis (PD) patients. However, a high CrEx ratio is not specific for noncompliance and may also be found in compliant patients with a relatively greater lean body mass (LBM). A cohort of 44 PD patients was followed up for a mean of 13 +/- 8 months after measurement of baseline CrEx ratio to investigate whether greater values were predictive of good or poor clinical outcomes. During this follow-up, 11 patients died, 12 patients transferred to hemodialysis, 4 patients underwent transplantation, 1 patient recovered renal function, and 16 patients continued on PD. The mean CrEx ratio in all patients was 1.14 +/- 0.32. It did not differ between men and women (1.15 versus 1.13, respectively; P = 0.76) but showed a trend toward being less in patients with diabetes (1.03 versus 1.19; P = 0. 19). The mean weekly Kt/V, weekly creatinine clearance, normalized protein equivalent of nitrogen appearance, and serum albumin values were 2.18 +/- 0.57, 73.57 +/- 33.75 L/1.73 m(2), 0.80 +/- 0.22 g/kg/d, and 3.22 +/- 0.59 g/dL, respectively. Technique failure (P < 0.001) and death (P < 0.05) were significantly more common in patients with a CrEx ratio less than 1 compared with those with a CrEx ratio greater than 1. On Cox regression analysis, the CrEx ratio was the only significant predictor of technique failure and was also an independent predictor of death. High CrEx ratio is a predictor of good, rather than poor, outcome in PD patients, perhaps because it is primarily an index of nutrition. This further weakens the argument that it is a reliable or useful marker of noncompliance.

High creatinine excretion ratio predicts a good outcome in peritoneal dialysis patients

The creatinine excretion (CrEx) ratio was first described as a method for detecting noncompliance in peritoneal dialysis (PD) patients. However, a high CrEx ratio is not specific for noncompliance and may also be found in compliant patients with a relatively greater lean body mass (LBM). A cohort of 44 PD patients was followed up for a mean of 13 +/- 8 months after measurement of baseline CrEx ratio to investigate whether greater values were predictive of good or poor clinical outcomes. During this follow-up, 11 patients died, 12 patients transferred to hemodialysis, 4 patients underwent transplantation, 1 patient recovered renal function, and 16 patients continued on PD. The mean CrEx ratio in all patients was 1.14 +/- 0.32. It did not differ between men and women (1.15 versus 1.13, respectively; P = 0.76) but showed a trend toward being less in patients with diabetes (1.03 versus 1.19; P = 0. 19). The mean weekly Kt/V, weekly creatinine clearance, normalized protein equivalent of nitrogen appearance, and serum albumin values were 2.18 +/- 0.57, 73.57 +/- 33.75 L/1.73 m(2), 0.80 +/- 0.22 g/kg/d, and 3.22 +/- 0.59 g/dL, respectively. Technique failure (P < 0.001) and death (P < 0.05) were significantly more common in patients with a CrEx ratio less than 1 compared with those with a CrEx ratio greater than 1. On Cox regression analysis, the CrEx ratio was the only significant predictor of technique failure and was also an independent predictor of death. High CrEx ratio is a predictor of good, rather than poor, outcome in PD patients, perhaps because it is primarily an index of nutrition. This further weakens the argument that it is a reliable or useful marker of noncompliance.

Comparison of measured and predicted creatinine excretion is an unreliable index of compliance in PD patients

OBJECTIVE

To evaluate the use of the ratio of measured to predicted creatinine excretion as an index of compliance in peritoneal dialysis (PD) patients.

DESIGN

A prospective analysis.

SETTING

Academic teaching hospital dialysis unit.

PATIENTS

Forty-three patients on PD.

MEASUREMENTS

Creatinine excretion in daily dialysate and urine collections was measured on one occasion in 10 patients and on two occasions in 33 patients, and, after adding an estimate for extrarenal creatinine degradation, was divided by predicted creatinine excretion to give a creatinine excretion ratio, which has been proposed as an index of compliance with exchanges in PD patients. Values above 1.24 have been suggested to indicate noncompliance. Lean body mass was also estimated from creatinine excretion.

RESULTS

The mean creatinine excretion ratio was 1.12, and 30% of patients had a value above 1.3. Only one patient admitted noncompliance. Studies on four consecutive days of guaranteed compliance in 7 patients with high ratios showed that creatinine excretion remained constant, suggesting that the patients were high creatinine producers rather than noncompliant. Creatinine excretion was stable when measured at intervals of days, but over months it tended to change markedly in many patients. Lean body mass estimations using creatinine excretion were low in most patients.

CONCLUSION

Comparison of measured and predicted creatinine excretion is not a reliable indicator of noncompliance because many compliant patients consistently excrete more creatinine than predicted. The standard formulas were not validated in dialysis patients and underestimate creatinine excretion significantly in many PD patients. Existing estimates in the literature of noncompliance, using this methodology, may not be accurate. Better methods of detecting this problem are required.