Anatomic pathology in Cuba before 1959: a personal recollection.

Reminiscing when reaching life's twilight is a human condition and hopefully leads to an objective self-evaluation of the past years. I have just done that with this recollection and now I can conclude that, in spite of the outcome of my professional life in Cuba, I remain convinced that one should not complete a journey just because it was started, that everything we learn in life will be sued in due time, and that we should always pursue our dreams because we become our best in the process.

How much formalin is enough to fix tissues?

A total of sixty samples from human breast, uterus, liver, skin and abdominal fat were fixed for 8; 24 and 48 hours at a room temperature of 20 to 22°C with neutral buffered formalin (NBF) with volume to tissue ratios of 1:1; 2:1; 5:1 and 10:1 and manually processed with isopropyl alcohol and mineral oil mixtures. All the slides prepared were evaluated as suitable for diagnostic purposes by nine pathologists from three different Russian histopathology institutions. The microtomy quality differences between the samples was not statistically significant for the different fixation volume ratios tested, but the differences between fixation periods and tissues types were, with 48 hours being the optimum fixation period, with skin and fat the most difficult to infiltrate. Neither the time and volume ratio combinations affected the pH of NBF or the immunostaining for vimentin in uterus or the histochemical periodic acid reaction or reticular demonstration fibers in liver. Fixing tissues with a ratio of NBF volume to tissue volume of 2:1 for 48 hours at 20-22°C was enough to assure a proper fixation and infiltration of the tested tissues and there is no objective reason to expect that other tissues will not behave similarly. It is suggested that in order to obtain good fixation and paraffin wax infiltration in around 10 hours, the fixation with NBF at 2:1 should be at 45°C with pressure and agitation.

Current status of cytology laboratories in anatomic pathology departments.

Details of cytology work in 103 US histology laboratories (histolabs) and in 200 from 18 other countries are presented. Data from 1345 additional US cytology practices surveyed from 1985 to 2004 are also included. The average annual workload in 130 histolabs from the United States and 12 other countries combined is 32 200 cases. The average annual workload in 173 histolabs from Spain and 5 Hispano-American countries is 20 000 cytology cases, a workload that is significantly lower (P < .0005) than that in US laboratories. Gynecologic cases, with an average of 1.2 slides each, represent 79% of all cytology accessions in all laboratories. The average annual workload per cytotechnologist (CT) is 6600 cases; this number is not significantly different between countries (P > .10 to P > .75) and is significantly correlated (P < .0008) with the laboratories' total workloads. In the United States, the average annual productivity per CT is 6700 cases with 1.8 slides each, for a daily screening of 55 to 60 slides. The annual benchmark is from 7900 to 8700 cases, equivalent to 14 300 to 15 000 slides per each full-time CT position. The benchmark per cytology aide is 17 000 to 20 000 cases. The number of CTs per histolab is significantly correlated (P < .0002) with its workload. In the United States, there is an average of 4 CTs and 2.7 cytology aides per laboratory, and the cytology tasks completed by the histology staff average 4.1 hours daily. The average turnaround time for cytology cases in the United States is approximately 6 calendar days, with 90% of all cases signed out between 7 and 8 calendar days. In addition to the productivity benchmarks, the pathology leadership must address the ergonomic conditions of the work when filling a new CT position because muscular discomfort caused by the microscopy work is a common occurrence.

Staffing benchmarks for histology laboratories.

This article summarizes annual workloads for staff positions and work flow productivity (WFP) values from 247 human pathology, 31 veterinary, and 35 forensic histology laboratories (histolabs). There are single summaries for veterinary and forensic histolabs, but the data from human pathology are divided into 2 groups because of statistically significant differences between those from Spain and 6 Hispano American countries (SpHA) and the rest from the United States and 17 other countries. The differences reflect the way the work is organized, but the histotechnicians and histotechnologists (histotechs) from SpHA have the same task productivity levels as those from any other country (Buesa RJ. Productivity standards for histology laboratories. [YADPA 50,552]). The information is also segregated by groups of histolabs with increasing workloads; this aspect also showed statistical differences. The information from human pathology histolabs other than those from SpHA were used to calculate staffing annual benchmarks for pathologists (from 3700 to 6500 cases depending on the histolab annual workload), pathology assistants (20,000 cases), staff histotechs (9900 blocks), cutting histotechs (15,000 blocks), histotechs doing special procedures (9500 slides if done manually or 15,000 slides with autostainers), dieners (100 autopsies), laboratory aides and transcriptionists (15,000 cases each), and secretaries (20,000 cases). There are also recommendations about workload limits for supervisory staff (lead techs and supervisors) and when neither is required. Each benchmark was related with the productivity of the different tasks they include (Buesa RJ. Productivity standards for histology laboratories. [YADPA 50,552]) to calculate the hours per year required to complete them. The relationship between workload and benchmarks allows the director of pathology to determine the staff needed for the efficient operation of the histolab.

Productivity standards for histology laboratories.

The information from 221 US histology laboratories (histolabs) and 104 from 24 other countries with workloads from 600 to 116 000 cases per year was used to calculate productivity standards for 23 technical and 27 nontechnical tasks and for 4 types of work flow indicators. The sample includes 254 human, 40 forensic, and 31 veterinary pathology services. Statistical analyses demonstrate that most productivity standards are not different between services or worldwide. The total workload for the US human pathology histolabs averaged 26 061 cases per year, with 54% between 10 000 and less than 30 000. The total workload for 70% of the histolabs from other countries was less than 20 000, with an average of 15 226 cases per year. The fundamental manual technical tasks in the histolab and their productivity standards are as follows: grossing (14 cases per hour), cassetting (54 cassettes per hour), embedding (50 blocks per hour), and cutting (24 blocks per hour). All the other tasks, each with their own productivity standards, can be completed by auxiliary staff or using automatic instruments. Depending on the level of automation of the histolab, all the tasks derived from a workload of 25 cases will require 15.8 to 17.7 hours of work completed by 2.4 to 2.7 employees with 18% of their working time not directly dedicated to the production of diagnostic slides. This article explains how to extrapolate this productivity calculation for any workload and different levels of automation. The overall performance standard for all the tasks, including 8 hours for automated tissue processing, is 3.2 to 3.5 blocks per hour; and its best indicator is the value of the gross work flow productivity that is essentially dependent on how the work is organized. This article also includes productivity standards for forensic and veterinary histolabs, but the staffing benchmarks for histolabs will be the subject of a separate article.

Adapting lean to histology laboratories.

Histology laboratories (histolabs) can increase productivity and reduce turnaround time and errors by using any one of several available management tools. After a few years of operation, all histolabs develop workflow problems. Histology laboratories handling more than 20,000 cases per year benefit the most from implementing management tools, as occurred in the 25 facilities summarized in this article. Discontinuous workflow, lack of "pulling" between steps, accepting unavoidable waiting times while working with small batches within work cells, and a workflow with an uneven rate of completion, are some of the adaptations required by the Lean system when it is used in histology because 70% of the tasks are manual and the flow has to be interrupted to add value to the pieces of tissue during tissue processing, no matter how short that step is. After all these adaptations are incorporated, the histolab becomes as "Lean" as it can be, and the qualifier is also a recognition of the effort and personnel involvement in the implementation. Given its service nature, productivity increments do not expand the histolab customer base and could lead to staffing reductions. This is one of the causes of reluctance by some employees for implementing these techniques which are mostly driven by cost reductions sought by insurance companies and administrators, and not necessarily because of a real medical need to reduce the turnaround time. Finally, any histolab wanting to improve its workflow can follow some easy steps presented here as a guide to accomplish that objective. These steps stress the need for the supervisors to insure that the personnel in the histology laboratory are being paid at a comparable rate as other histolabs in the area.

Histology without xylene.

After the hazardous effects of xylene became indisputable in the 1970s, many potential substitutes became available, some with as many if not more hazards. This article discusses the inadequacy of 5 vegetable oils as substitutes, as well as the characteristics of 22 D-limonene-based substitutes, all less effective in their chemical role, some capable of inducing health problems, and costing more than twice as much as xylene. Some of the 35 alkane-based substitutes discussed are effective for tissue processing, less toxic, with a cost about the same as xylene, but are not very effective for dewaxing and other staining tasks. Isopropanol (2-propanol) alone or mixed with molten paraffin is a technically acceptable and cost-effective substitute for xylene for tissue processing, but in this study, we demonstrate that the best clearing agents from the sectioning quality and diagnostic value point of view, with automated or manual protocols, are mixtures of 5:1 and 2:1 isopropanol and mineral oil, followed by undiluted mineral oil, all at 50 degrees C, making them a safer and cheaper substitute than xylene. Using a 1.7% dishwasher soap aqueous solution at 90 degrees C to dewax before staining and oven drying the stained sections before coverslipping will eliminate xylene from the staining tasks. Tissue processors retorts and conduits can be dewaxed with a 2% solution of a strong glassware laboratory detergent. These 4 methodologies will make the histology laboratory xylene-free but, due to the natural resistance to change, many histotechs will be reluctant to adopt them if they think that their technical expertise could be jeopardized, and the only way these changes will succeed is if the pathologists, as stewards of the histology laboratory, commit to their implementation.

Histology aging workforce and what to do about it.

There are 28,400 histotechs now working in human surgical and forensic pathology, half of whom will reach retirement age within the next 4 years, and to compensate for those retiring and to increase their number to the 31,200 needed in 2015, a 3-pronged solution is required. Firstly, each individual medical laboratory has to implement a uniform salary scale for all its members with equivalent professional level that will probably delay the retirement plans of some histotechs and will allow the flow of personnel between its different areas. Secondly, a new certification of "qualification in histology" should be created so medical technologists can cover for retiring histotechs and also could find new working positions in laboratories that may be contemplating staff reductions because of more productive instruments and workflow schemes. Finally, given the historical examination passing rates, it is necessary to enroll at least 4,965 students in accredited histology programs (709 annually), and for this to happen, either the present number of 33 programs has to be increased by 17 (to a total of 50) with a similar capacity each to those now in operation or 2 to 3 distance learning programs with a capacity of 85 to 125 each have to be created after the example of some already existing. This solution will also require that local students soon to enter junior colleges are informed about these programs and work opportunities. To assure the success of any of the 3 approaches, it is imperative that the pathologists get involved, individually for the first one, and collectively for the other two; the pathologists should bring these solutions to their respective societies and college boards and meetings and sound the alarm on this problem that will adversely impact their work and their overall patient care. The pathologists have to be aware of this very grave situation-that the histotechs' retirement clocks are ticking and that the time to act is now!

Histology without formalin?

Because formalin is toxic, carcinogenic, and a poor preserver of nucleic acids, for more than 20 years, there have been numerous attempts to find a substitute, with as many different alternative fixatives, none totally successful. With a fast penetration, formaldehyde is a slow and reversible fixative that requires 24 to 48 hours to completely bind to tissue; thus, any surgical specimen arriving to the laboratory between 8 AM and 4 PM and processed conventionally for the slides to be ready the following day will be only between 30% and 66% bound and even less fixed when the dehydration starts, resulting in an additional and also incomplete alcoholic fixation. This causes infiltration problems and can affect subsequent tests, especially immunohistochemistry. Formaldehyde fixation is tissue thickness independent between 16 microm and 4 mm but is faster at above room temperature, so the fixation of specimens with less than 24 hours in formalin can be improved if the fixing stations in the conventional tissue processors are set at 40 degrees C. If the safety measures are improved to offer a work environment with a time weighted average level of 0.4 ppm, and the contact with formalin is reduced to a minimum by discouraging its neutralization and limiting the recycling practice to filtering methods, formalin could remain as the routine fixative, with modified methacarn for those specimens requiring nucleic acids studies. This is a preferred solution than having to validate all the standard and special procedures, including those US Food and Drug Administration approved, if formalin is replaced by another fixative without its advantages. To the question posed in the title of this article, the answer is "Yes, it can be done, but that is neither likely nor worth it!"

Salaries in histology.

An analysis of histology salaries from the last 4 national surveys conducted by the American Society of Clinical Pathologists is presented. The regional variations within and between years for histology salaries presented in the last 4 national surveys of medical laboratory specialties are not statistically significant. Local variations greater than the national variations reflect the preponderant effect of local supply and demand over regional characteristics. Salaries by hospitals are significantly different only between 2 size categories and the supervisors' salary. There is no correlation between the salary increase for any histology position in any one year and the vacancy level in the previous year. On the other hand, the correlation between histotechnicians' salaries and both the cost of living and the median income are significant, as well as between the latter and the supervisors' salary. The histotechnologists' salaries are significantly correlated with the consumer price index but not with the inflation rate. A survey of histology salaries in foreign countries was also undertaken and compared with salaries in the United States. National salaries rank close to the general average for 10 foreign countries when expressed as ratios with the personal gross domestic product or with the countries' minimum wage. For the midpoint salary ranges, the United States ranks fourth after Canada, the United Kingdom, and Australia, the latter 3 countries with structured pay rates adjusted to local costs of living in contrast with United States' salary characteristics. Histology salaries rest on negotiations within each employer's salary structure and fluctuate according to license level, documented studies, special training(s), years of experience, references, and the ability to negotiate, where each side tries to take advantage of the other. The result is a heterogeneous and chaotic salary situation driven by personal and local needs, where the histology worker usually ends underpaid, especially in nonmedical settings.

Histology safety: now and then.

Histology safety usually focuses on general laboratory issues, but this article concentrates on the hazards affecting the individual histotech and their evolution in the last half a century. Using the information from a survey especially designed for the occasion, the hazards were divided into 4 groups, and their prevalence was expressed as percentages for national and foreign laboratories. All the laboratories received a "safety index" (SI) with an average value of 0.77 +/- 0.11 for 63 national laboratories and 0.69 +/- 0.13 for 22 foreign laboratories, these 2 averages being statistically different (P < .02). The historical evolution of the SI required answering the same questionnaire retrospectively, and so it was done for 17 laboratories with an SI average of 0.27 +/- 0.12 for 1955/1989 and 0.77 +/- 0.13, almost 3 times larger for 1990/2007, with improvement of all safety issues. The technological, organizational, and regulatory advances before 1989 showed an unremarkable effect on the SI, and the only circumstance considered as the driving force behind the almost triple increment of the SI during 1990/2007 was the awareness that the AIDS epidemic instilled in the minds and consciences of the medical laboratory personnel in general. Even after almost tripling the average SI value in 2007, national histology laboratories obtained a grade average of "C+" only, leaving room for improvement.

Microwave-assisted tissue processing: real impact on the histology workflow.

Tissue processing is just one of many tasks in the histology workflow and accounts for 3% to 34% of the total time; it is technology dependent, but all other tasks are independent of this step and constitute the remaining 66% to 97% of the total time. The best histology workflow is one of fewer than 50 specimen loads processed sequentially in the shortest time possible, with postprocessing tasks completed in approximately the same time as the preprocessing and processing steps combined. Larger loads determine a total workflow too lengthy for an efficient continuous operation. This objective may be obtained with microwave-assisted instruments or by optimizing conventional instruments usage. As a major capital equipment investment, changing technology and selecting an instrument should also include a cost-effectiveness analysis.

Histology: a unique area of the medical laboratory.

Fundamental differences in samples, procedures, nature of results, automation, productivity, staffing levels, and background decision making along work flow and turnaround times characterize histology as a unique area within the medical laboratory. For histology laboratories to function successfully, individual and collective training, well-defined goals, and implemented accountabilities with effective supervision are required. The pathologist, as immediate client of the histology laboratory, has to be involved in the whole operation to assure optimal patient care.